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!function(e){if("object"==typeof exports&&"undefined"!=typeof module)module.exports=e();else if("function"==typeof define&&define.amd)define([],e);else{var f;"undefined"!=typeof window?f=window:"undefined"!=typeof global?f=global:"undefined"!=typeof self&&(f=self),f.PouchDB=e()}}(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o 0) ? opts.keys.slice(opts.skip) : opts.keys;
  if (opts.descending) {
    keys.reverse();
  }
  if (!keys.length) {
    return api._allDocs({limit: 0}, callback);
  }
  var finalResults = {
    offset: opts.skip
  };
  return Promise.all(keys.map(function (key) {
    var subOpts = utils.extend(true, {key: key, deleted: 'ok'}, opts);
    ['limit', 'skip', 'keys'].forEach(function (optKey) {
      delete subOpts[optKey];
    });
    return new Promise(function (resolve, reject) {
      api._allDocs(subOpts, function (err, res) {
        if (err) {
          return reject(err);
        }
        finalResults.total_rows = res.total_rows;
        resolve(res.rows[0] || {key: key, error: 'not_found'});
      });
    });
  })).then(function (results) {
    finalResults.rows = results;
    return finalResults;
  });
}

utils.inherits(AbstractPouchDB, EventEmitter);
module.exports = AbstractPouchDB;

function AbstractPouchDB() {
  var self = this;
  EventEmitter.call(this);

  var listeners = 0, changes;
  var eventNames = ['change', 'delete', 'create', 'update'];
  this.on('newListener', function (eventName) {
    if (~eventNames.indexOf(eventName)) {
      if (listeners) {
        listeners++;
        return;
      } else {
        listeners++;
      }
    } else {
      return;
    }
    var lastChange = 0;
    changes = this.changes({
      conflicts: true,
      include_docs: true,
      continuous: true,
      since: 'now',
      onChange: function (change) {
        if (change.seq <= lastChange) {
          return;
        }
        lastChange = change.seq;
        self.emit('change', change);
        if (change.doc._deleted) {
          self.emit('delete', change);
        } else if (change.doc._rev.split('-')[0] === '1') {
          self.emit('create', change);
        } else {
          self.emit('update', change);
        }
      }
    });
  });
  this.on('removeListener', function (eventName) {
    if (~eventNames.indexOf(eventName)) {
      listeners--;
      if (listeners) {
        return;
      }
    } else {
      return;
    }
    changes.cancel();
  });
}

AbstractPouchDB.prototype.post =
  utils.adapterFun('post', function (doc, opts, callback) {
  if (typeof opts === 'function') {
    callback = opts;
    opts = {};
  }
  if (typeof doc !== 'object' || Array.isArray(doc)) {
    return callback(errors.error(errors.NOT_AN_OBJECT));
  }
  this.bulkDocs({docs: [doc]}, opts, yankError(callback));
});

AbstractPouchDB.prototype.put =
  utils.adapterFun('put', utils.getArguments(function (args) {
  var temp, temptype, opts, callback;
  var doc = args.shift();
  var id = '_id' in doc;
  if (typeof doc !== 'object' || Array.isArray(doc)) {
    callback = args.pop();
    return callback(errors.error(errors.NOT_AN_OBJECT));
  }
  doc = utils.clone(doc);
  while (true) {
    temp = args.shift();
    temptype = typeof temp;
    if (temptype === "string" && !id) {
      doc._id = temp;
      id = true;
    } else if (temptype === "string" && id && !('_rev' in doc)) {
      doc._rev = temp;
    } else if (temptype === "object") {
      opts = temp;
    } else if (temptype === "function") {
      callback = temp;
    }
    if (!args.length) {
      break;
    }
  }
  opts = opts || {};
  var error = utils.invalidIdError(doc._id);
  if (error) {
    return callback(error);
  }
  if (utils.isLocalId(doc._id) && typeof this._putLocal === 'function') {
    if (doc._deleted) {
      return this._removeLocal(doc, callback);
    } else {
      return this._putLocal(doc, callback);
    }
  }
  this.bulkDocs({docs: [doc]}, opts, yankError(callback));
}));

AbstractPouchDB.prototype.putAttachment =
  utils.adapterFun('putAttachment', function (docId, attachmentId, rev,
                                              blob, type, callback) {
  var api = this;
  if (typeof type === 'function') {
    callback = type;
    type = blob;
    blob = rev;
    rev = null;
  }
  if (typeof type === 'undefined') {
    type = blob;
    blob = rev;
    rev = null;
  }

  function createAttachment(doc) {
    doc._attachments = doc._attachments || {};
    doc._attachments[attachmentId] = {
      content_type: type,
      data: blob
    };
    return api.put(doc);
  }

  return api.get(docId).then(function (doc) {
    if (doc._rev !== rev) {
      throw errors.error(errors.REV_CONFLICT);
    }

    return createAttachment(doc);
  }, function (err) {
     // create new doc
    if (err.reason === errors.MISSING_DOC.message) {
      return createAttachment({_id: docId});
    } else {
      throw err;
    }
  });
});

AbstractPouchDB.prototype.removeAttachment =
  utils.adapterFun('removeAttachment', function (docId, attachmentId, rev,
                                                 callback) {
  var self = this;
  self.get(docId, function (err, obj) {
    if (err) {
      callback(err);
      return;
    }
    if (obj._rev !== rev) {
      callback(errors.error(errors.REV_CONFLICT));
      return;
    }
    if (!obj._attachments) {
      return callback();
    }
    delete obj._attachments[attachmentId];
    if (Object.keys(obj._attachments).length === 0) {
      delete obj._attachments;
    }
    self.put(obj, callback);
  });
});

AbstractPouchDB.prototype.remove =
  utils.adapterFun('remove', function (docOrId, optsOrRev, opts, callback) {
  var doc;
  if (typeof optsOrRev === 'string') {
    // id, rev, opts, callback style
    doc = {
      _id: docOrId,
      _rev: optsOrRev
    };
    if (typeof opts === 'function') {
      callback = opts;
      opts = {};
    }
  } else {
    // doc, opts, callback style
    doc = docOrId;
    if (typeof optsOrRev === 'function') {
      callback = optsOrRev;
      opts = {};
    } else {
      callback = opts;
      opts = optsOrRev;
    }
  }
  opts = utils.clone(opts || {});
  opts.was_delete = true;
  var newDoc = {_id: doc._id, _rev: (doc._rev || opts.rev)};
  newDoc._deleted = true;
  if (utils.isLocalId(newDoc._id) && typeof this._removeLocal === 'function') {
    return this._removeLocal(doc, callback);
  }
  this.bulkDocs({docs: [newDoc]}, opts, yankError(callback));
});

AbstractPouchDB.prototype.revsDiff =
  utils.adapterFun('revsDiff', function (req, opts, callback) {
  if (typeof opts === 'function') {
    callback = opts;
    opts = {};
  }
  opts = utils.clone(opts);
  var ids = Object.keys(req);

  if (!ids.length) {
    return callback(null, {});
  }

  var count = 0;
  var missing = new utils.Map();

  function addToMissing(id, revId) {
    if (!missing.has(id)) {
      missing.set(id, {missing: []});
    }
    missing.get(id).missing.push(revId);
  }

  function processDoc(id, rev_tree) {
    // Is this fast enough? Maybe we should switch to a set simulated by a map
    var missingForId = req[id].slice(0);
    merge.traverseRevTree(rev_tree, function (isLeaf, pos, revHash, ctx,
      opts) {
        var rev = pos + '-' + revHash;
        var idx = missingForId.indexOf(rev);
        if (idx === -1) {
          return;
        }

        missingForId.splice(idx, 1);
        if (opts.status !== 'available') {
          addToMissing(id, rev);
        }
      });

    // Traversing the tree is synchronous, so now `missingForId` contains
    // revisions that were not found in the tree
    missingForId.forEach(function (rev) {
      addToMissing(id, rev);
    });
  }

  ids.map(function (id) {
    this._getRevisionTree(id, function (err, rev_tree) {
      if (err && err.status === 404 && err.message === 'missing') {
        missing.set(id, {missing: req[id]});
      } else if (err) {
        return callback(err);
      } else {
        processDoc(id, rev_tree);
      }

      if (++count === ids.length) {
        // convert LazyMap to object
        var missingObj = {};
        missing.forEach(function (value, key) {
          missingObj[key] = value;
        });
        return callback(null, missingObj);
      }
    });
  }, this);
});

// compact one document and fire callback
// by compacting we mean removing all revisions which
// are further from the leaf in revision tree than max_height
AbstractPouchDB.prototype.compactDocument =
  utils.adapterFun('compactDocument', function (docId, maxHeight, callback) {
  var self = this;
  this._getRevisionTree(docId, function (err, revTree) {
    if (err) {
      return callback(err);
    }
    var height = computeHeight(revTree);
    var candidates = [];
    var revs = [];
    Object.keys(height).forEach(function (rev) {
      if (height[rev] > maxHeight) {
        candidates.push(rev);
      }
    });

    merge.traverseRevTree(revTree, function (isLeaf, pos, revHash, ctx, opts) {
      var rev = pos + '-' + revHash;
      if (opts.status === 'available' && candidates.indexOf(rev) !== -1) {
        revs.push(rev);
      }
    });
    self._doCompaction(docId, revs, callback);
  });
});

// compact the whole database using single document
// compaction
AbstractPouchDB.prototype.compact =
  utils.adapterFun('compact', function (opts, callback) {
  if (typeof opts === 'function') {
    callback = opts;
    opts = {};
  }
  var self = this;

  opts = utils.clone(opts || {});

  self.get('_local/compaction')["catch"](function () {
    return false;
  }).then(function (doc) {
    if (typeof self._compact === 'function') {
      if (doc && doc.last_seq) {
        opts.last_seq = doc.last_seq;
      }
      return self._compact(opts, callback);
    }

  });
});
AbstractPouchDB.prototype._compact = function (opts, callback) {
  var self = this;
  var changesOpts = {
    returnDocs: false,
    last_seq: opts.last_seq || 0
  };
  var promises = [];

  function onChange(row) {
    promises.push(self.compactDocument(row.id, 0));
  }
  function onComplete(resp) {
    var lastSeq = resp.last_seq;
    Promise.all(promises).then(function () {
      return upsert(self, '_local/compaction', function deltaFunc(doc) {
        if (!doc.last_seq || doc.last_seq < lastSeq) {
          doc.last_seq = lastSeq;
          return doc;
        }
        return false; // somebody else got here first, don't update
      });
    }).then(function () {
      callback(null, {ok: true});
    })["catch"](callback);
  }
  self.changes(changesOpts)
    .on('change', onChange)
    .on('complete', onComplete)
    .on('error', callback);
};
/* Begin api wrappers. Specific functionality to storage belongs in the 
   _[method] */
AbstractPouchDB.prototype.get =
  utils.adapterFun('get', function (id, opts, callback) {
  if (typeof opts === 'function') {
    callback = opts;
    opts = {};
  }
  if (typeof id !== 'string') {
    return callback(errors.error(errors.INVALID_ID));
  }
  if (utils.isLocalId(id) && typeof this._getLocal === 'function') {
    return this._getLocal(id, callback);
  }
  var leaves = [], self = this;

  function finishOpenRevs() {
    var result = [];
    var count = leaves.length;
    if (!count) {
      return callback(null, result);
    }
    // order with open_revs is unspecified
    leaves.forEach(function (leaf) {
      self.get(id, {
        rev: leaf,
        revs: opts.revs,
        attachments: opts.attachments
      }, function (err, doc) {
        if (!err) {
          result.push({ok: doc});
        } else {
          result.push({missing: leaf});
        }
        count--;
        if (!count) {
          callback(null, result);
        }
      });
    });
  }

  if (opts.open_revs) {
    if (opts.open_revs === "all") {
      this._getRevisionTree(id, function (err, rev_tree) {
        if (err) {
          return callback(err);
        }
        leaves = merge.collectLeaves(rev_tree).map(function (leaf) {
          return leaf.rev;
        });
        finishOpenRevs();
      });
    } else {
      if (Array.isArray(opts.open_revs)) {
        leaves = opts.open_revs;
        for (var i = 0; i < leaves.length; i++) {
          var l = leaves[i];
          // looks like it's the only thing couchdb checks
          if (!(typeof(l) === "string" && /^\d+-/.test(l))) {
            return callback(errors.error(errors.INVALID_REV));
          }
        }
        finishOpenRevs();
      } else {
        return callback(errors.error(errors.UNKNOWN_ERROR,
          'function_clause'));
      }
    }
    return; // open_revs does not like other options
  }

  return this._get(id, opts, function (err, result) {
    opts = utils.clone(opts);
    if (err) {
      return callback(err);
    }

    var doc = result.doc;
    var metadata = result.metadata;
    var ctx = result.ctx;

    if (opts.conflicts) {
      var conflicts = merge.collectConflicts(metadata);
      if (conflicts.length) {
        doc._conflicts = conflicts;
      }
    }

    if (utils.isDeleted(metadata, doc._rev)) {
      doc._deleted = true;
    }

    if (opts.revs || opts.revs_info) {
      var paths = merge.rootToLeaf(metadata.rev_tree);
      var path = arrayFirst(paths, function (arr) {
        return arr.ids.map(function (x) { return x.id; })
          .indexOf(doc._rev.split('-')[1]) !== -1;
      });

      var indexOfRev = path.ids.map(function (x) {return x.id; })
        .indexOf(doc._rev.split('-')[1]) + 1;
      var howMany = path.ids.length - indexOfRev;
      path.ids.splice(indexOfRev, howMany);
      path.ids.reverse();

      if (opts.revs) {
        doc._revisions = {
          start: (path.pos + path.ids.length) - 1,
          ids: path.ids.map(function (rev) {
            return rev.id;
          })
        };
      }
      if (opts.revs_info) {
        var pos =  path.pos + path.ids.length;
        doc._revs_info = path.ids.map(function (rev) {
          pos--;
          return {
            rev: pos + '-' + rev.id,
            status: rev.opts.status
          };
        });
      }
    }

    if (opts.local_seq) {
      utils.info('The "local_seq" option is deprecated and will be removed');
      doc._local_seq = result.metadata.seq;
    }

    if (opts.attachments && doc._attachments) {
      var attachments = doc._attachments;
      var count = Object.keys(attachments).length;
      if (count === 0) {
        return callback(null, doc);
      }
      Object.keys(attachments).forEach(function (key) {
        this._getAttachment(attachments[key],
                            {encode: true, ctx: ctx}, function (err, data) {
          var att = doc._attachments[key];
          att.data = data;
          delete att.stub;
          delete att.length;
          if (!--count) {
            callback(null, doc);
          }
        });
      }, self);
    } else {
      if (doc._attachments) {
        for (var key in doc._attachments) {
          if (doc._attachments.hasOwnProperty(key)) {
            doc._attachments[key].stub = true;
          }
        }
      }
      callback(null, doc);
    }
  });
});

AbstractPouchDB.prototype.getAttachment =
  utils.adapterFun('getAttachment', function (docId, attachmentId, opts,
                                              callback) {
  var self = this;
  if (opts instanceof Function) {
    callback = opts;
    opts = {};
  }
  opts = utils.clone(opts);
  this._get(docId, opts, function (err, res) {
    if (err) {
      return callback(err);
    }
    if (res.doc._attachments && res.doc._attachments[attachmentId]) {
      opts.ctx = res.ctx;
      self._getAttachment(res.doc._attachments[attachmentId], opts, callback);
    } else {
      return callback(errors.error(errors.MISSING_DOC));
    }
  });
});

AbstractPouchDB.prototype.allDocs =
  utils.adapterFun('allDocs', function (opts, callback) {
  if (typeof opts === 'function') {
    callback = opts;
    opts = {};
  }
  opts = utils.clone(opts);
  opts.skip = typeof opts.skip !== 'undefined' ? opts.skip : 0;
  if ('keys' in opts) {
    if (!Array.isArray(opts.keys)) {
      return callback(new TypeError('options.keys must be an array'));
    }
    var incompatibleOpt =
      ['startkey', 'endkey', 'key'].filter(function (incompatibleOpt) {
      return incompatibleOpt in opts;
    })[0];
    if (incompatibleOpt) {
      callback(errors.error(errors.QUERY_PARSE_ERROR,
        'Query parameter `' + incompatibleOpt +
        '` is not compatible with multi-get'
      ));
      return;
    }
    if (this.type() !== 'http') {
      return allDocsKeysQuery(this, opts, callback);
    }
  }

  return this._allDocs(opts, callback);
});

AbstractPouchDB.prototype.changes = function (opts, callback) {
  if (typeof opts === 'function') {
    callback = opts;
    opts = {};
  }
  return new Changes(this, opts, callback);
};

AbstractPouchDB.prototype.close =
  utils.adapterFun('close', function (callback) {
  this._closed = true;
  return this._close(callback);
});

AbstractPouchDB.prototype.info = utils.adapterFun('info', function (callback) {
  var self = this;
  this._info(function (err, info) {
    if (err) {
      return callback(err);
    }
    // assume we know better than the adapter, unless it informs us
    info.db_name = info.db_name || self._db_name;
    info.auto_compaction = !!(self.auto_compaction && self.type() !== 'http');
    callback(null, info);
  });
});

AbstractPouchDB.prototype.id = utils.adapterFun('id', function (callback) {
  return this._id(callback);
});

AbstractPouchDB.prototype.type = function () {
  return (typeof this._type === 'function') ? this._type() : this.adapter;
};

AbstractPouchDB.prototype.bulkDocs =
  utils.adapterFun('bulkDocs', function (req, opts, callback) {
  if (typeof opts === 'function') {
    callback = opts;
    opts = {};
  }

  opts = utils.clone(opts);

  if (Array.isArray(req)) {
    req = {
      docs: req
    };
  }

  if (!req || !req.docs || !Array.isArray(req.docs)) {
    return callback(errors.error(errors.MISSING_BULK_DOCS));
  }

  for (var i = 0; i < req.docs.length; ++i) {
    if (typeof req.docs[i] !== 'object' || Array.isArray(req.docs[i])) {
      return callback(errors.error(errors.NOT_AN_OBJECT));
    }
  }

  req = utils.clone(req);
  if (!('new_edits' in opts)) {
    if ('new_edits' in req) {
      opts.new_edits = req.new_edits;
    } else {
      opts.new_edits = true;
    }
  }

  if (!opts.new_edits && this.type() !== 'http') {
    // ensure revisions of the same doc are sorted, so that
    // the local adapter processes them correctly (#2935)
    req.docs.sort(function (a, b) {
      var idCompare = utils.compare(a._id, b._id);
      if (idCompare !== 0) {
        return idCompare;
      }
      var aStart = a._revisions ? a._revisions.start : 0;
      var bStart = b._revisions ? b._revisions.start : 0;
      return utils.compare(aStart, bStart);
    });
  }

  req.docs.forEach(function (doc) {
    if (doc._deleted) {
      delete doc._attachments; // ignore atts for deleted docs
    }
  });

  return this._bulkDocs(req, opts, function (err, res) {
    if (err) {
      return callback(err);
    }
    if (!opts.new_edits) {
      // this is what couch does when new_edits is false
      res = res.filter(function (x) {
        return x.error;
      });
    }
    callback(null, res);
  });
});

AbstractPouchDB.prototype.registerDependentDatabase =
  utils.adapterFun('registerDependentDatabase', function (dependentDb,
                                                          callback) {
  var depDB = new this.constructor(dependentDb, this.__opts || {});

  function diffFun(doc) {
    doc.dependentDbs = doc.dependentDbs || {};
    if (doc.dependentDbs[dependentDb]) {
      return false; // no update required
    }
    doc.dependentDbs[dependentDb] = true;
    return doc;
  }
  upsert(this, '_local/_pouch_dependentDbs', diffFun, function (err) {
    if (err) {
      return callback(err);
    }
    return callback(null, {db: depDB});
  });
});

},{}],2:[function(_dereq_,module,exports){
(function (process){
"use strict";

var CHANGES_BATCH_SIZE = 25;

// according to http://stackoverflow.com/a/417184/680742,
// the de factor URL length limit is 2000 characters.
// but since most of our measurements don't take the full
// URL into account, we fudge it a bit.
// TODO: we could measure the full URL to enforce exactly 2000 chars
var MAX_URL_LENGTH = 1800;

var utils = _dereq_(32);
var errors = _dereq_(19);
var log = _dereq_(38)('pouchdb:http');
var isBrowser = typeof process === 'undefined' || process.browser;
var buffer = _dereq_(18);

function encodeDocId(id) {
  if (/^_(design|local)/.test(id)) {
    return id;
  }
  return encodeURIComponent(id);
}

function preprocessAttachments(doc) {
  if (!doc._attachments || !Object.keys(doc._attachments)) {
    return utils.Promise.resolve();
  }

  return utils.Promise.all(Object.keys(doc._attachments).map(function (key) {
    var attachment = doc._attachments[key];
    if (attachment.data && typeof attachment.data !== 'string') {
      if (isBrowser) {
        return new utils.Promise(function (resolve) {
          utils.readAsBinaryString(attachment.data, function (binary) {
            attachment.data = utils.btoa(binary);
            resolve();
          });
        });
      } else {
        attachment.data = attachment.data.toString('base64');
      }
    }
  }));
}

// Get all the information you possibly can about the URI given by name and
// return it as a suitable object.
function getHost(name, opts) {
  // If the given name contains "http:"
  if (/http(s?):/.test(name)) {
    // Prase the URI into all its little bits
    var uri = utils.parseUri(name);

    // Store the fact that it is a remote URI
    uri.remote = true;

    // Store the user and password as a separate auth object
    if (uri.user || uri.password) {
      uri.auth = {username: uri.user, password: uri.password};
    }

    // Split the path part of the URI into parts using '/' as the delimiter
    // after removing any leading '/' and any trailing '/'
    var parts = uri.path.replace(/(^\/|\/$)/g, '').split('/');

    // Store the first part as the database name and remove it from the parts
    // array
    uri.db = parts.pop();

    // Restore the path by joining all the remaining parts (all the parts
    // except for the database name) with '/'s
    uri.path = parts.join('/');
    opts = opts || {};
    opts = utils.clone(opts);
    uri.headers = opts.headers || (opts.ajax && opts.ajax.headers) || {};

    if (opts.auth || uri.auth) {
      var nAuth = opts.auth || uri.auth;
      var token = utils.btoa(nAuth.username + ':' + nAuth.password);
      uri.headers.Authorization = 'Basic ' + token;
    }

    if (opts.headers) {
      uri.headers = opts.headers;
    }

    return uri;
  }

  // If the given name does not contain 'http:' then return a very basic object
  // with no host, the current path, the given name as the database name and no
  // username/password
  return {host: '', path: '/', db: name, auth: false};
}

// Generate a URL with the host data given by opts and the given path
function genDBUrl(opts, path) {
  return genUrl(opts, opts.db + '/' + path);
}

// Generate a URL with the host data given by opts and the given path
function genUrl(opts, path) {
  if (opts.remote) {
    // If the host already has a path, then we need to have a path delimiter
    // Otherwise, the path delimiter is the empty string
    var pathDel = !opts.path ? '' : '/';

    // If the host already has a path, then we need to have a path delimiter
    // Otherwise, the path delimiter is the empty string
    return opts.protocol + '://' + opts.host + ':' + opts.port + '/' +
           opts.path + pathDel + path;
  }

  return '/' + path;
}

// Implements the PouchDB API for dealing with CouchDB instances over HTTP
function HttpPouch(opts, callback) {
  // The functions that will be publicly available for HttpPouch
  var api = this;
  api.getHost = opts.getHost ? opts.getHost : getHost;

  // Parse the URI given by opts.name into an easy-to-use object
  var host = api.getHost(opts.name, opts);

  // Generate the database URL based on the host
  var dbUrl = genDBUrl(host, '');

  api.getUrl = function () {return dbUrl; };
  api.getHeaders = function () {return utils.clone(host.headers); };

  var ajaxOpts = opts.ajax || {};
  opts = utils.clone(opts);
  function ajax(options, callback) {
    var reqOpts = utils.extend({}, ajaxOpts, options);
    log(reqOpts.method + ' ' + reqOpts.url);
    return utils.ajax(reqOpts, callback);
  }

  // Create a new CouchDB database based on the given opts
  var createDB = function () {
    ajax({headers: host.headers, method: 'PUT', url: dbUrl}, function (err) {
      // If we get an "Unauthorized" error
      if (err && err.status === 401) {
        // Test if the database already exists
        ajax({headers: host.headers, method: 'HEAD', url: dbUrl},
             function (err) {
          // If there is still an error
          if (err) {
            // Give the error to the callback to deal with
            callback(err);
          } else {
            // Continue as if there had been no errors
            callback(null, api);
          }
        });
        // If there were no errros or if the only error is "Precondition Failed"
        // (note: "Precondition Failed" occurs when we try to create a database
        // that already exists)
      } else if (!err || err.status === 412) {
        // Continue as if there had been no errors
        callback(null, api);
      } else {
        callback(err);
      }
    });
  };

  if (!opts.skipSetup) {
    ajax({headers: host.headers, method: 'GET', url: dbUrl}, function (err) {
      //check if the db exists
      if (err) {
        if (err.status === 404) {
          utils.explain404(
            'PouchDB is just detecting if the remote DB exists.');
          //if it doesn't, create it
          createDB();
        } else {
          callback(err);
        }
      } else {
        //go do stuff with the db
        callback(null, api);
      }
    });
  }

  api.type = function () {
    return 'http';
  };

  api.id = utils.adapterFun('id', function (callback) {
    ajax({
      headers: host.headers,
      method: 'GET',
      url: genUrl(host, '')
    }, function (err, result) {
      var uuid = (result && result.uuid) ?
        result.uuid + host.db : genDBUrl(host, '');
      callback(null, uuid);
    });
  });

  api.request = utils.adapterFun('request', function (options, callback) {
    options.headers = host.headers;
    options.url = genDBUrl(host, options.url);
    ajax(options, callback);
  });

  // Sends a POST request to the host calling the couchdb _compact function
  //    version: The version of CouchDB it is running
  api.compact = utils.adapterFun('compact', function (opts, callback) {
    if (typeof opts === 'function') {
      callback = opts;
      opts = {};
    }
    opts = utils.clone(opts);
    ajax({
      headers: host.headers,
      url: genDBUrl(host, '_compact'),
      method: 'POST'
    }, function () {
      function ping() {
        api.info(function (err, res) {
          if (!res.compact_running) {
            callback(null, {ok: true});
          } else {
            setTimeout(ping, opts.interval || 200);
          }
        });
      }
      // Ping the http if it's finished compaction
      if (typeof callback === "function") {
        ping();
      }
    });
  });

  // Calls GET on the host, which gets back a JSON string containing
  //    couchdb: A welcome string
  //    version: The version of CouchDB it is running
  api._info = function (callback) {
    ajax({
      headers: host.headers,
      method: 'GET',
      url: genDBUrl(host, '')
    }, function (err, res) {
      if (err) {
        callback(err);
      } else {
        res.host = genDBUrl(host, '');
        callback(null, res);
      }
    });
  };

  // Get the document with the given id from the database given by host.
  // The id could be solely the _id in the database, or it may be a
  // _design/ID or _local/ID path
  api.get = utils.adapterFun('get', function (id, opts, callback) {
    // If no options were given, set the callback to the second parameter
    if (typeof opts === 'function') {
      callback = opts;
      opts = {};
    }
    opts = utils.clone(opts);
    if (opts.auto_encode === undefined) {
      opts.auto_encode = true;
    }

    // List of parameters to add to the GET request
    var params = [];

    // If it exists, add the opts.revs value to the list of parameters.
    // If revs=true then the resulting JSON will include a field
    // _revisions containing an array of the revision IDs.
    if (opts.revs) {
      params.push('revs=true');
    }

    // If it exists, add the opts.revs_info value to the list of parameters.
    // If revs_info=true then the resulting JSON will include the field
    // _revs_info containing an array of objects in which each object
    // representing an available revision.
    if (opts.revs_info) {
      params.push('revs_info=true');
    }

    if (opts.local_seq) {
      params.push('local_seq=true');
    }
    // If it exists, add the opts.open_revs value to the list of parameters.
    // If open_revs=all then the resulting JSON will include all the leaf
    // revisions. If open_revs=["rev1", "rev2",...] then the resulting JSON
    // will contain an array of objects containing data of all revisions
    if (opts.open_revs) {
      if (opts.open_revs !== "all") {
        opts.open_revs = JSON.stringify(opts.open_revs);
      }
      params.push('open_revs=' + opts.open_revs);
    }

    // If it exists, add the opts.attachments value to the list of parameters.
    // If attachments=true the resulting JSON will include the base64-encoded
    // contents in the "data" property of each attachment.
    if (opts.attachments) {
      params.push('attachments=true');
    }

    // If it exists, add the opts.rev value to the list of parameters.
    // If rev is given a revision number then get the specified revision.
    if (opts.rev) {
      params.push('rev=' + opts.rev);
    }

    // If it exists, add the opts.conflicts value to the list of parameters.
    // If conflicts=true then the resulting JSON will include the field
    // _conflicts containing all the conflicting revisions.
    if (opts.conflicts) {
      params.push('conflicts=' + opts.conflicts);
    }

    // Format the list of parameters into a valid URI query string
    params = params.join('&');
    params = params === '' ? '' : '?' + params;

    if (opts.auto_encode) {
      id = encodeDocId(id);
    }

    // Set the options for the ajax call
    var options = {
      headers: host.headers,
      method: 'GET',
      url: genDBUrl(host, id + params)
    };

    // If the given id contains at least one '/' and the part before the '/'
    // is NOT "_design" and is NOT "_local"
    // OR
    // If the given id contains at least two '/' and the part before the first
    // '/' is "_design".
    // TODO This second condition seems strange since if parts[0] === '_design'
    // then we already know that parts[0] !== '_local'.
    var parts = id.split('/');
    if ((parts.length > 1 && parts[0] !== '_design' && parts[0] !== '_local') ||
        (parts.length > 2 && parts[0] === '_design' && parts[0] !== '_local')) {
      // Binary is expected back from the server
      options.binary = true;
    }

    // Get the document
    ajax(options, function (err, doc, xhr) {
      // If the document does not exist, send an error to the callback
      if (err) {
        return callback(err);
      }

      // Send the document to the callback
      callback(null, doc, xhr);
    });
  });

  // Delete the document given by doc from the database given by host.
  api.remove = utils.adapterFun('remove',
      function (docOrId, optsOrRev, opts, callback) {
    var doc;
    if (typeof optsOrRev === 'string') {
      // id, rev, opts, callback style
      doc = {
        _id: docOrId,
        _rev: optsOrRev
      };
      if (typeof opts === 'function') {
        callback = opts;
        opts = {};
      }
    } else {
      // doc, opts, callback style
      doc = docOrId;
      if (typeof optsOrRev === 'function') {
        callback = optsOrRev;
        opts = {};
      } else {
        callback = opts;
        opts = optsOrRev;
      }
    }

    var rev = (doc._rev || opts.rev);

    // Delete the document
    ajax({
      headers: host.headers,
      method: 'DELETE',
      url: genDBUrl(host, encodeDocId(doc._id)) + '?rev=' + rev
    }, callback);
  });

  function encodeAttachmentId(attachmentId) {
    return attachmentId.split("/").map(encodeURIComponent).join("/");
  }

  // Get the attachment
  api.getAttachment =
    utils.adapterFun('getAttachment', function (docId, attachmentId, opts,
                                                callback) {
    if (typeof opts === 'function') {
      callback = opts;
      opts = {};
    }
    opts = utils.clone(opts);
    if (opts.auto_encode === undefined) {
      opts.auto_encode = true;
    }
    if (opts.auto_encode) {
      docId = encodeDocId(docId);
    }
    opts.auto_encode = false;
    api.get(docId + '/' + encodeAttachmentId(attachmentId), opts, callback);
  });

  // Remove the attachment given by the id and rev
  api.removeAttachment =
    utils.adapterFun('removeAttachment', function (docId, attachmentId, rev,
                                                   callback) {

    var url = genDBUrl(host, encodeDocId(docId) + '/' +
      encodeAttachmentId(attachmentId)) + '?rev=' + rev;

    ajax({
      headers: host.headers,
      method: 'DELETE',
      url: url
    }, callback);
  });

  // Add the attachment given by blob and its contentType property
  // to the document with the given id, the revision given by rev, and
  // add it to the database given by host.
  api.putAttachment =
    utils.adapterFun('putAttachment', function (docId, attachmentId, rev, blob,
                                                type, callback) {
    if (typeof type === 'function') {
      callback = type;
      type = blob;
      blob = rev;
      rev = null;
    }
    if (typeof type === 'undefined') {
      type = blob;
      blob = rev;
      rev = null;
    }
    var id = encodeDocId(docId) + '/' + encodeAttachmentId(attachmentId);
    var url = genDBUrl(host, id);
    if (rev) {
      url += '?rev=' + rev;
    }

    if (typeof blob === 'string') {
      var binary;
      try {
        binary = utils.atob(blob);
      } catch (err) {
        // it's not base64-encoded, so throw error
        return callback(errors.error(errors.BAD_ARG,
                        'Attachments need to be base64 encoded'));
      }
      if (isBrowser) {
        blob = utils.createBlob([utils.fixBinary(binary)], {type: type});
      } else {
        blob = binary ? new buffer(binary, 'binary') : '';
      }
    }

    var opts = {
      headers: utils.clone(host.headers),
      method: 'PUT',
      url: url,
      processData: false,
      body: blob,
      timeout: 60000
    };
    opts.headers['Content-Type'] = type;
    // Add the attachment
    ajax(opts, callback);
  });

  // Add the document given by doc (in JSON string format) to the database
  // given by host. This fails if the doc has no _id field.
  api.put = utils.adapterFun('put', utils.getArguments(function (args) {
    var temp, temptype, opts;
    var doc = args.shift();
    var id = '_id' in doc;
    var callback = args.pop();
    if (typeof doc !== 'object' || Array.isArray(doc)) {
      return callback(errors.error(errors.NOT_AN_OBJECT));
    }

    doc = utils.clone(doc);

    preprocessAttachments(doc).then(function () {
      while (true) {
        temp = args.shift();
        temptype = typeof temp;
        if (temptype === "string" && !id) {
          doc._id = temp;
          id = true;
        } else if (temptype === "string" && id && !('_rev' in doc)) {
          doc._rev = temp;
        } else if (temptype === "object") {
          opts = utils.clone(temp);
        }
        if (!args.length) {
          break;
        }
      }
      opts = opts || {};
      var error = utils.invalidIdError(doc._id);
      if (error) {
        throw error;
      }

      // List of parameter to add to the PUT request
      var params = [];

      // If it exists, add the opts.new_edits value to the list of parameters.
      // If new_edits = false then the database will NOT assign this document a
      // new revision number
      if (opts && typeof opts.new_edits !== 'undefined') {
        params.push('new_edits=' + opts.new_edits);
      }

      // Format the list of parameters into a valid URI query string
      params = params.join('&');
      if (params !== '') {
        params = '?' + params;
      }

      // Add the document
      ajax({
        headers: host.headers,
        method: 'PUT',
        url: genDBUrl(host, encodeDocId(doc._id)) + params,
        body: doc
      }, function (err, res) {
        if (err) {
          return callback(err);
        }
        res.ok = true;
        callback(null, res);
      });
    })["catch"](callback);

  }));

  // Add the document given by doc (in JSON string format) to the database
  // given by host. This does not assume that doc is a new document 
  // (i.e. does not have a _id or a _rev field.)
  api.post = utils.adapterFun('post', function (doc, opts, callback) {
    // If no options were given, set the callback to be the second parameter
    if (typeof opts === 'function') {
      callback = opts;
      opts = {};
    }
    opts = utils.clone(opts);
    if (typeof doc !== 'object') {
      return callback(errors.error(errors.NOT_AN_OBJECT));
    }
    if (! ("_id" in doc)) {
      doc._id = utils.uuid();
    }
    api.put(doc, opts, function (err, res) {
      if (err) {
        return callback(err);
      }
      res.ok = true;
      callback(null, res);
    });
  });

  // Update/create multiple documents given by req in the database
  // given by host.
  api._bulkDocs = function (req, opts, callback) {
    // If opts.new_edits exists add it to the document data to be
    // send to the database.
    // If new_edits=false then it prevents the database from creating
    // new revision numbers for the documents. Instead it just uses
    // the old ones. This is used in database replication.
    if (typeof opts.new_edits !== 'undefined') {
      req.new_edits = opts.new_edits;
    }

    utils.Promise.all(req.docs.map(preprocessAttachments)).then(function () {
      // Update/create the documents
      ajax({
        headers: host.headers,
        method: 'POST',
        url: genDBUrl(host, '_bulk_docs'),
        body: req
      }, function (err, results) {
        if (err) {
          return callback(err);
        }
        results.forEach(function (result) {
          result.ok = true; // smooths out cloudant not adding this
        });
        callback(null, results);
      });
    })["catch"](callback);
  };

  // Get a listing of the documents in the database given
  // by host and ordered by increasing id.
  api.allDocs = utils.adapterFun('allDocs', function (opts, callback) {
    if (typeof opts === 'function') {
      callback = opts;
      opts = {};
    }
    opts = utils.clone(opts);
    // List of parameters to add to the GET request
    var params = [];
    var body;
    var method = 'GET';

    if (opts.conflicts) {
      params.push('conflicts=true');
    }

    // If opts.descending is truthy add it to params
    if (opts.descending) {
      params.push('descending=true');
    }

    // If opts.include_docs exists, add the include_docs value to the
    // list of parameters.
    // If include_docs=true then include the associated document with each
    // result.
    if (opts.include_docs) {
      params.push('include_docs=true');
    }

    if (opts.attachments) {
      // added in CouchDB 1.6.0
      params.push('attachments=true');
    }

    if (opts.key) {
      params.push('key=' + encodeURIComponent(JSON.stringify(opts.key)));
    }

    // If opts.startkey exists, add the startkey value to the list of
    // parameters.
    // If startkey is given then the returned list of documents will
    // start with the document whose id is startkey.
    if (opts.startkey) {
      params.push('startkey=' +
        encodeURIComponent(JSON.stringify(opts.startkey)));
    }

    // If opts.endkey exists, add the endkey value to the list of parameters.
    // If endkey is given then the returned list of docuemnts will
    // end with the document whose id is endkey.
    if (opts.endkey) {
      params.push('endkey=' + encodeURIComponent(JSON.stringify(opts.endkey)));
    }

    if (typeof opts.inclusive_end !== 'undefined') {
      params.push('inclusive_end=' + !!opts.inclusive_end);
    }

    // If opts.limit exists, add the limit value to the parameter list.
    if (typeof opts.limit !== 'undefined') {
      params.push('limit=' + opts.limit);
    }

    if (typeof opts.skip !== 'undefined') {
      params.push('skip=' + opts.skip);
    }

    // Format the list of parameters into a valid URI query string
    params = params.join('&');
    if (params !== '') {
      params = '?' + params;
    }

    if (typeof opts.keys !== 'undefined') {


      var keysAsString =
        'keys=' + encodeURIComponent(JSON.stringify(opts.keys));
      if (keysAsString.length + params.length + 1 <= MAX_URL_LENGTH) {
        // If the keys are short enough, do a GET. we do this to work around
        // Safari not understanding 304s on POSTs (see issue #1239)
        params += (params.indexOf('?') !== -1 ? '&' : '?') + keysAsString;
      } else {
        // If keys are too long, issue a POST request to circumvent GET
        // query string limits
        // see http://wiki.apache.org/couchdb/HTTP_view_API#Querying_Options
        method = 'POST';
        body = JSON.stringify({keys: opts.keys});
      }
    }

    // Get the document listing
    ajax({
      headers: host.headers,
      method: method,
      url: genDBUrl(host, '_all_docs' + params),
      body: body
    }, callback);
  });

  // Get a list of changes made to documents in the database given by host.
  // TODO According to the README, there should be two other methods here,
  // api.changes.addListener and api.changes.removeListener.
  api._changes = function (opts) {
    // We internally page the results of a changes request, this means
    // if there is a large set of changes to be returned we can start
    // processing them quicker instead of waiting on the entire
    // set of changes to return and attempting to process them at once
    var batchSize = 'batch_size' in opts ? opts.batch_size : CHANGES_BATCH_SIZE;

    opts = utils.clone(opts);
    opts.timeout = opts.timeout || 30 * 1000;

    // We give a 5 second buffer for CouchDB changes to respond with
    // an ok timeout
    var params = { timeout: opts.timeout - (5 * 1000) };
    var limit = (typeof opts.limit !== 'undefined') ? opts.limit : false;
    if (limit === 0) {
      limit = 1;
    }
    var returnDocs;
    if ('returnDocs' in opts) {
      returnDocs = opts.returnDocs;
    } else {
      returnDocs = true;
    }
    //
    var leftToFetch = limit;

    if (opts.style) {
      params.style = opts.style;
    }

    if (opts.include_docs || opts.filter && typeof opts.filter === 'function') {
      params.include_docs = true;
    }

    if (opts.attachments) {
      params.attachments = true;
    }

    if (opts.continuous) {
      params.feed = 'longpoll';
    }

    if (opts.conflicts) {
      params.conflicts = true;
    }

    if (opts.descending) {
      params.descending = true;
    }

    if (opts.filter && typeof opts.filter === 'string') {
      params.filter = opts.filter;
      if (opts.filter === '_view' &&
          opts.view &&
          typeof opts.view === 'string') {
        params.view = opts.view;
      }
    }

    // If opts.query_params exists, pass it through to the changes request.
    // These parameters may be used by the filter on the source database.
    if (opts.query_params && typeof opts.query_params === 'object') {
      for (var param_name in opts.query_params) {
        if (opts.query_params.hasOwnProperty(param_name)) {
          params[param_name] = opts.query_params[param_name];
        }
      }
    }

    var method = 'GET';
    var body;

    if (opts.doc_ids) {
      // set this automagically for the user; it's annoying that couchdb
      // requires both a "filter" and a "doc_ids" param.
      params.filter = '_doc_ids';

      var docIdsJson = JSON.stringify(opts.doc_ids);

      if (docIdsJson.length < MAX_URL_LENGTH) {
        params.doc_ids = docIdsJson;
      } else {
        // anything greater than ~2000 is unsafe for gets, so
        // use POST instead
        method = 'POST';
        body = {doc_ids: opts.doc_ids };
      }
    }

    if (opts.continuous && api._useSSE) {
      return  api.sse(opts, params, returnDocs);
    }
    var xhr;
    var lastFetchedSeq;

    // Get all the changes starting wtih the one immediately after the
    // sequence number given by since.
    var fetch = function (since, callback) {
      if (opts.aborted) {
        return;
      }
      params.since = since;
      if (typeof params.since === "object") {
        params.since = JSON.stringify(params.since);
      }

      if (opts.descending) {
        if (limit) {
          params.limit = leftToFetch;
        }
      } else {
        params.limit = (!limit || leftToFetch > batchSize) ?
          batchSize : leftToFetch;
      }

      var paramStr = '?' + Object.keys(params).map(function (k) {
        return k + '=' + params[k];
      }).join('&');

      // Set the options for the ajax call
      var xhrOpts = {
        headers: host.headers,
        method: method,
        url: genDBUrl(host, '_changes' + paramStr),
        // _changes can take a long time to generate, especially when filtered
        timeout: opts.timeout,
        body: body
      };
      lastFetchedSeq = since;

      if (opts.aborted) {
        return;
      }

      // Get the changes
      xhr = ajax(xhrOpts, callback);
    };

    // If opts.since exists, get all the changes from the sequence
    // number given by opts.since. Otherwise, get all the changes
    // from the sequence number 0.
    var fetchTimeout = 10;
    var fetchRetryCount = 0;

    var results = {results: []};

    var fetched = function (err, res) {
      if (opts.aborted) {
        return;
      }
      var raw_results_length = 0;
      // If the result of the ajax call (res) contains changes (res.results)
      if (res && res.results) {
        raw_results_length = res.results.length;
        results.last_seq = res.last_seq;
        // For each change
        var req = {};
        req.query = opts.query_params;
        res.results = res.results.filter(function (c) {
          leftToFetch--;
          var ret = utils.filterChange(opts)(c);
          if (ret) {
            if (returnDocs) {
              results.results.push(c);
            }
            utils.call(opts.onChange, c);
          }
          return ret;
        });
      } else if (err) {
        // In case of an error, stop listening for changes and call
        // opts.complete
        opts.aborted = true;
        utils.call(opts.complete, err);
        return;
      }

      // The changes feed may have timed out with no results
      // if so reuse last update sequence
      if (res && res.last_seq) {
        lastFetchedSeq = res.last_seq;
      }

      var finished = (limit && leftToFetch <= 0) ||
        (res && raw_results_length < batchSize) ||
        (opts.descending);

      if ((opts.continuous && !(limit && leftToFetch <= 0)) || !finished) {
        // Increase retry delay exponentially as long as errors persist
        if (err) {
          fetchRetryCount += 1;
        } else {
          fetchRetryCount = 0;
        }
        var timeoutMultiplier = 1 << fetchRetryCount;
        var retryWait = fetchTimeout * timeoutMultiplier;
        var maximumWait = opts.maximumWait || 30000;

        if (retryWait > maximumWait) {
          utils.call(opts.complete, err || errors.error(errors.UNKNOWN_ERROR));
          return;
        }

        // Queue a call to fetch again with the newest sequence number
        setTimeout(function () { fetch(lastFetchedSeq, fetched); }, retryWait);
      } else {
        // We're done, call the callback
        utils.call(opts.complete, null, results);
      }
    };

    fetch(opts.since || 0, fetched);

    // Return a method to cancel this method from processing any more
    return {
      cancel: function () {
        opts.aborted = true;
        if (xhr) {
          xhr.abort();
        }
      }
    };
  };

  api.sse = function (opts, params, returnDocs) {
    params.feed = 'eventsource';
    params.since = opts.since || 0;
    params.limit = opts.limit;
    delete params.timeout;
    var paramStr = '?' + Object.keys(params).map(function (k) {
      return k + '=' + params[k];
    }).join('&');
    var url = genDBUrl(host, '_changes' + paramStr);
    var source = new EventSource(url);
    var results = {
      results: [],
      last_seq: false
    };
    var dispatched = false;
    var open = false;
    source.addEventListener('message', msgHandler, false);
    source.onopen = function () {
      open = true;
    };
    source.onerror = errHandler;
    return {
      cancel: function () {
        if (dispatched) {
          return dispatched.cancel();
        }
        source.removeEventListener('message', msgHandler, false);
        source.close();
      }
    };
    function msgHandler(e) {
      var data = JSON.parse(e.data);
      if (returnDocs) {
        results.results.push(data);
      }
      results.last_seq = data.seq;
      utils.call(opts.onChange, data);
    }
    function errHandler(err) {
      source.removeEventListener('message', msgHandler, false);
      if (open === false) {
        // errored before it opened
        // likely doesn't support EventSource
        api._useSSE = false;
        dispatched = api._changes(opts);
        return;
      }
      source.close();
      utils.call(opts.complete, err);
    }
    
  };

  api._useSSE = false;
  // Currently disabled due to failing chrome tests in saucelabs
  // api._useSSE = typeof global.EventSource === 'function';

  // Given a set of document/revision IDs (given by req), tets the subset of
  // those that do NOT correspond to revisions stored in the database.
  // See http://wiki.apache.org/couchdb/HttpPostRevsDiff
  api.revsDiff = utils.adapterFun('revsDiff', function (req, opts, callback) {
    // If no options were given, set the callback to be the second parameter
    if (typeof opts === 'function') {
      callback = opts;
      opts = {};
    }

    // Get the missing document/revision IDs
    ajax({
      headers: host.headers,
      method: 'POST',
      url: genDBUrl(host, '_revs_diff'),
      body: JSON.stringify(req)
    }, callback);
  });

  api._close = function (callback) {
    callback();
  };

  api.destroy = utils.adapterFun('destroy', function (callback) {
    ajax({
      url: genDBUrl(host, ''),
      method: 'DELETE',
      headers: host.headers
    }, function (err, resp) {
      if (err) {
        api.emit('error', err);
        callback(err);
      } else {
        api.emit('destroyed');
        callback(null, resp);
      }
    });
  });
}

// Delete the HttpPouch specified by the given name.
HttpPouch.destroy = utils.toPromise(function (name, opts, callback) {
  var host = getHost(name, opts);
  opts = opts || {};
  if (typeof opts === 'function') {
    callback = opts;
    opts = {};
  }
  opts = utils.clone(opts);
  opts.headers = host.headers;
  opts.method = 'DELETE';
  opts.url = genDBUrl(host, '');
  var ajaxOpts = opts.ajax || {};
  opts = utils.extend({}, opts, ajaxOpts);
  utils.ajax(opts, callback);
});

// HttpPouch is a valid adapter.
HttpPouch.valid = function () {
  return true;
};

module.exports = HttpPouch;

}).call(this,_dereq_(37))
},{}],3:[function(_dereq_,module,exports){
'use strict';

var utils = _dereq_(32);
var idbConstants = _dereq_(5);
var DETECT_BLOB_SUPPORT_STORE = idbConstants.DETECT_BLOB_SUPPORT_STORE;

//
// Detect blob support. Chrome didn't support it until version 38.
// In version 37 they had a broken version where PNGs (and possibly
// other binary types) aren't stored correctly, because when you fetch
// them, the content type is always null.
//
// Furthermore, they have some outstanding bugs where blobs occasionally
// are read by FileReader as null, or by ajax as 404s.
//
// Sadly we use the 404 bug to detect the FileReader bug, so if they
// get fixed independently and released in different versions of Chrome,
// then the bug could come back. So it's worthwhile to watch these issues:
// 404 bug: https://code.google.com/p/chromium/issues/detail?id=447916
// FileReader bug: https://code.google.com/p/chromium/issues/detail?id=447836
//
function checkBlobSupport(txn, idb) {
  return new utils.Promise(function (resolve, reject) {
    var blob = utils.createBlob([''], {type: 'image/png'});
    txn.objectStore(DETECT_BLOB_SUPPORT_STORE).put(blob, 'key');
    txn.oncomplete = function () {
      // have to do it in a separate transaction, else the correct
      // content type is always returned
      var blobTxn = idb.transaction([DETECT_BLOB_SUPPORT_STORE],
        'readwrite');
      var getBlobReq = blobTxn.objectStore(
        DETECT_BLOB_SUPPORT_STORE).get('key');
      getBlobReq.onerror = reject;
      getBlobReq.onsuccess = function (e) {

        var storedBlob = e.target.result;
        var url = URL.createObjectURL(storedBlob);

        utils.ajax({
          url: url,
          cache: true,
          binary: true
        }, function (err, res) {
          if (err && err.status === 405) {
            // firefox won't let us do that. but firefox doesn't
            // have the blob type bug that Chrome does, so that's ok
            resolve(true);
          } else {
            resolve(!!(res && res.type === 'image/png'));
            if (err && err.status === 404) {
              utils.explain404('PouchDB is just detecting blob URL support.');
            }
          }
          URL.revokeObjectURL(url);
        });
      };
    };
  })["catch"](function () {
    return false; // error, so assume unsupported
  });
}

module.exports = checkBlobSupport;
},{}],4:[function(_dereq_,module,exports){
'use strict';

var utils = _dereq_(32);
var errors = _dereq_(19);
var idbUtils = _dereq_(6);
var idbConstants = _dereq_(5);

var ATTACH_AND_SEQ_STORE = idbConstants.ATTACH_AND_SEQ_STORE;
var ATTACH_STORE = idbConstants.ATTACH_STORE;
var BY_SEQ_STORE = idbConstants.BY_SEQ_STORE;
var DOC_STORE = idbConstants.DOC_STORE;
var LOCAL_STORE = idbConstants.LOCAL_STORE;
var META_STORE = idbConstants.META_STORE;

var compactRevs = idbUtils.compactRevs;
var decodeMetadata = idbUtils.decodeMetadata;
var encodeMetadata = idbUtils.encodeMetadata;
var idbError = idbUtils.idbError;
var openTransactionSafely = idbUtils.openTransactionSafely;

function idbBulkDocs(req, opts, api, idb, Changes, callback) {
  var docInfos = req.docs;
  var txn;
  var docStore;
  var bySeqStore;
  var attachStore;
  var attachAndSeqStore;
  var docInfoError;

  for (var i = 0, len = docInfos.length; i < len; i++) {
    var doc = docInfos[i];
    if (doc._id && utils.isLocalId(doc._id)) {
      continue;
    }
    doc = docInfos[i] = utils.parseDoc(doc, opts.new_edits);
    if (doc.error && !docInfoError) {
      docInfoError = doc;
    }
  }

  if (docInfoError) {
    return callback(docInfoError);
  }

  var results = new Array(docInfos.length);
  var fetchedDocs = new utils.Map();
  var preconditionErrored = false;
  var blobType = api._blobSupport ? 'blob' : 'base64';

  utils.preprocessAttachments(docInfos, blobType, function (err) {
    if (err) {
      return callback(err);
    }
    startTransaction();
  });

  function startTransaction() {

    var stores = [
      DOC_STORE, BY_SEQ_STORE,
      ATTACH_STORE, META_STORE,
      LOCAL_STORE, ATTACH_AND_SEQ_STORE
    ];
    var txnResult = openTransactionSafely(idb, stores, 'readwrite');
    if (txnResult.error) {
      return callback(txnResult.error);
    }
    txn = txnResult.txn;
    txn.onerror = idbError(callback);
    txn.ontimeout = idbError(callback);
    txn.oncomplete = complete;
    docStore = txn.objectStore(DOC_STORE);
    bySeqStore = txn.objectStore(BY_SEQ_STORE);
    attachStore = txn.objectStore(ATTACH_STORE);
    attachAndSeqStore = txn.objectStore(ATTACH_AND_SEQ_STORE);

    verifyAttachments(function (err) {
      if (err) {
        preconditionErrored = true;
        return callback(err);
      }
      fetchExistingDocs();
    });
  }

  function processDocs() {

    utils.processDocs(docInfos, api, fetchedDocs, txn, results,
      writeDoc, opts);
  }

  function fetchExistingDocs() {

    if (!docInfos.length) {
      return;
    }

    var numFetched = 0;

    function checkDone() {
      if (++numFetched === docInfos.length) {
        processDocs();
      }
    }

    function readMetadata(event) {
      var metadata = decodeMetadata(event.target.result);

      if (metadata) {
        fetchedDocs.set(metadata.id, metadata);
      }
      checkDone();
    }

    for (var i = 0, len = docInfos.length; i < len; i++) {
      var docInfo = docInfos[i];
      if (docInfo._id && utils.isLocalId(docInfo._id)) {
        checkDone(); // skip local docs
        continue;
      }
      var req = docStore.get(docInfo.metadata.id);
      req.onsuccess = readMetadata;
    }
  }

  function complete() {
    if (preconditionErrored) {
      return;
    }

    Changes.notify(api._name);
    api._docCount = -1; // invalidate
    callback(null, results);
  }

  function verifyAttachment(digest, callback) {

    var req = attachStore.get(digest);
    req.onsuccess = function (e) {
      if (!e.target.result) {
        var err = errors.error(errors.MISSING_STUB,
          'unknown stub attachment with digest ' +
          digest);
        err.status = 412;
        callback(err);
      } else {
        callback();
      }
    };
  }

  function verifyAttachments(finish) {


    var digests = [];
    docInfos.forEach(function (docInfo) {
      if (docInfo.data && docInfo.data._attachments) {
        Object.keys(docInfo.data._attachments).forEach(function (filename) {
          var att = docInfo.data._attachments[filename];
          if (att.stub) {
            digests.push(att.digest);
          }
        });
      }
    });
    if (!digests.length) {
      return finish();
    }
    var numDone = 0;
    var err;

    function checkDone() {
      if (++numDone === digests.length) {
        finish(err);
      }
    }
    digests.forEach(function (digest) {
      verifyAttachment(digest, function (attErr) {
        if (attErr && !err) {
          err = attErr;
        }
        checkDone();
      });
    });
  }

  function writeDoc(docInfo, winningRev, deleted, callback, isUpdate,
                    delta, resultsIdx) {

    var doc = docInfo.data;
    doc._id = docInfo.metadata.id;
    doc._rev = docInfo.metadata.rev;

    if (deleted) {
      doc._deleted = true;
    }

    var hasAttachments = doc._attachments &&
      Object.keys(doc._attachments).length;
    if (hasAttachments) {
      return writeAttachments(docInfo, winningRev, deleted,
        callback, isUpdate, resultsIdx);
    }

    finishDoc(docInfo, winningRev, deleted,
      callback, isUpdate, resultsIdx);
  }

  function autoCompact(docInfo) {

    var revsToDelete = utils.compactTree(docInfo.metadata);
    compactRevs(revsToDelete, docInfo.metadata.id, txn);
  }

  function finishDoc(docInfo, winningRev, deleted, callback, isUpdate,
                     resultsIdx) {

    var doc = docInfo.data;
    var metadata = docInfo.metadata;

    doc._doc_id_rev = metadata.id + '::' + metadata.rev;
    delete doc._id;
    delete doc._rev;

    function afterPutDoc(e) {
      if (isUpdate && api.auto_compaction) {
        autoCompact(docInfo);
      }
      metadata.seq = e.target.result;
      // Current _rev is calculated from _rev_tree on read
      delete metadata.rev;
      var metadataToStore = encodeMetadata(metadata, winningRev, deleted);
      var metaDataReq = docStore.put(metadataToStore);
      metaDataReq.onsuccess = afterPutMetadata;
    }

    function afterPutDocError(e) {
      // ConstraintError, need to update, not put (see #1638 for details)
      e.preventDefault(); // avoid transaction abort
      e.stopPropagation(); // avoid transaction onerror
      var index = bySeqStore.index('_doc_id_rev');
      var getKeyReq = index.getKey(doc._doc_id_rev);
      getKeyReq.onsuccess = function (e) {
        var putReq = bySeqStore.put(doc, e.target.result);
        putReq.onsuccess = afterPutDoc;
      };
    }

    function afterPutMetadata() {
      results[resultsIdx] = {
        ok: true,
        id: metadata.id,
        rev: winningRev
      };
      fetchedDocs.set(docInfo.metadata.id, docInfo.metadata);
      insertAttachmentMappings(docInfo, metadata.seq, callback);
    }

    var putReq = bySeqStore.put(doc);

    putReq.onsuccess = afterPutDoc;
    putReq.onerror = afterPutDocError;
  }

  function writeAttachments(docInfo, winningRev, deleted, callback,
                            isUpdate, resultsIdx) {


    var doc = docInfo.data;

    var numDone = 0;
    var attachments = Object.keys(doc._attachments);

    function collectResults() {
      if (numDone === attachments.length) {
        finishDoc(docInfo, winningRev, deleted, callback, isUpdate,
          resultsIdx);
      }
    }

    function attachmentSaved() {
      numDone++;
      collectResults();
    }

    attachments.forEach(function (key) {
      var att = docInfo.data._attachments[key];
      if (!att.stub) {
        var data = att.data;
        delete att.data;
        var digest = att.digest;
        saveAttachment(digest, data, attachmentSaved);
      } else {
        numDone++;
        collectResults();
      }
    });
  }

  // map seqs to attachment digests, which
  // we will need later during compaction
  function insertAttachmentMappings(docInfo, seq, callback) {

    var attsAdded = 0;
    var attsToAdd = Object.keys(docInfo.data._attachments || {});

    if (!attsToAdd.length) {
      return callback();
    }

    function checkDone() {
      if (++attsAdded === attsToAdd.length) {
        callback();
      }
    }

    function add(att) {
      var digest = docInfo.data._attachments[att].digest;
      var req = attachAndSeqStore.put({
        seq: seq,
        digestSeq: digest + '::' + seq
      });

      req.onsuccess = checkDone;
      req.onerror = function (e) {
        // this callback is for a constaint error, which we ignore
        // because this docid/rev has already been associated with
        // the digest (e.g. when new_edits == false)
        e.preventDefault(); // avoid transaction abort
        e.stopPropagation(); // avoid transaction onerror
        checkDone();
      };
    }
    for (var i = 0; i < attsToAdd.length; i++) {
      add(attsToAdd[i]); // do in parallel
    }
  }

  function saveAttachment(digest, data, callback) {


    var getKeyReq = attachStore.count(digest);
    getKeyReq.onsuccess = function(e) {
      var count = e.target.result;
      if (count) {
        return callback(); // already exists
      }
      var newAtt = {
        digest: digest,
        body: data
      };
      var putReq = attachStore.put(newAtt);
      putReq.onsuccess = callback;
    };
  }
}

module.exports = idbBulkDocs;
},{}],5:[function(_dereq_,module,exports){
'use strict';

// IndexedDB requires a versioned database structure, so we use the
// version here to manage migrations.
exports.ADAPTER_VERSION = 5;

// The object stores created for each database
// DOC_STORE stores the document meta data, its revision history and state
// Keyed by document id
exports. DOC_STORE = 'document-store';
// BY_SEQ_STORE stores a particular version of a document, keyed by its
// sequence id
exports.BY_SEQ_STORE = 'by-sequence';
// Where we store attachments
exports.ATTACH_STORE = 'attach-store';
// Where we store many-to-many relations
// between attachment digests and seqs
exports.ATTACH_AND_SEQ_STORE = 'attach-seq-store';

// Where we store database-wide meta data in a single record
// keyed by id: META_STORE
exports.META_STORE = 'meta-store';
// Where we store local documents
exports.LOCAL_STORE = 'local-store';
// Where we detect blob support
exports.DETECT_BLOB_SUPPORT_STORE = 'detect-blob-support';
},{}],6:[function(_dereq_,module,exports){
(function (process){
'use strict';

var errors = _dereq_(19);
var utils = _dereq_(32);
var constants = _dereq_(5);

function tryCode(fun, that, args) {
  try {
    fun.apply(that, args);
  } catch (err) { // shouldn't happen
    if (typeof PouchDB !== 'undefined') {
      PouchDB.emit('error', err);
    }
  }
}

exports.taskQueue = {
  running: false,
  queue: []
};

exports.applyNext = function () {
  if (exports.taskQueue.running || !exports.taskQueue.queue.length) {
    return;
  }
  exports.taskQueue.running = true;
  var item = exports.taskQueue.queue.shift();
  item.action(function (err, res) {
    tryCode(item.callback, this, [err, res]);
    exports.taskQueue.running = false;
    process.nextTick(exports.applyNext);
  });
};

exports.idbError = function (callback) {
  return function (event) {
    var message = (event.target && event.target.error &&
      event.target.error.name) || event.target;
    callback(errors.error(errors.IDB_ERROR, message, event.type));
  };
};

// Unfortunately, the metadata has to be stringified
// when it is put into the database, because otherwise
// IndexedDB can throw errors for deeply-nested objects.
// Originally we just used JSON.parse/JSON.stringify; now
// we use this custom vuvuzela library that avoids recursion.
// If we could do it all over again, we'd probably use a
// format for the revision trees other than JSON.
exports.encodeMetadata = function (metadata, winningRev, deleted) {
  return {
    data: utils.safeJsonStringify(metadata),
    winningRev: winningRev,
    deletedOrLocal: deleted ? '1' : '0',
    seq: metadata.seq, // highest seq for this doc
    id: metadata.id
  };
};

exports.decodeMetadata = function (storedObject) {
  if (!storedObject) {
    return null;
  }
  var metadata = utils.safeJsonParse(storedObject.data);
  metadata.winningRev = storedObject.winningRev;
  metadata.deletedOrLocal = storedObject.deletedOrLocal === '1';
  metadata.seq = storedObject.seq;
  return metadata;
};

// read the doc back out from the database. we don't store the
// _id or _rev because we already have _doc_id_rev.
exports.decodeDoc = function (doc) {
  if (!doc) {
    return doc;
  }
  var idx = utils.lastIndexOf(doc._doc_id_rev, ':');
  doc._id = doc._doc_id_rev.substring(0, idx - 1);
  doc._rev = doc._doc_id_rev.substring(idx + 1);
  delete doc._doc_id_rev;
  return doc;
};

// Read a blob from the database, encoding as necessary
// and translating from base64 if the IDB doesn't support
// native Blobs
exports.readBlobData = function (body, type, encode, callback) {
  if (encode) {
    if (!body) {
      callback('');
    } else if (typeof body !== 'string') { // we have blob support
      utils.readAsBinaryString(body, function (binary) {
        callback(utils.btoa(binary));
      });
    } else { // no blob support
      callback(body);
    }
  } else {
    if (!body) {
      callback(utils.createBlob([''], {type: type}));
    } else if (typeof body !== 'string') { // we have blob support
      callback(body);
    } else { // no blob support
      body = utils.fixBinary(atob(body));
      callback(utils.createBlob([body], {type: type}));
    }
  }
};

exports.fetchAttachmentsIfNecessary = function (doc, opts, txn, cb) {
  var attachments = Object.keys(doc._attachments || {});
  if (!attachments.length) {
    return cb && cb();
  }
  var numDone = 0;

  function checkDone() {
    if (++numDone === attachments.length && cb) {
      cb();
    }
  }

  function fetchAttachment(doc, att) {
    var attObj = doc._attachments[att];
    var digest = attObj.digest;
    var req = txn.objectStore(constants.ATTACH_STORE).get(digest);
    req.onsuccess = function (e) {
      attObj.body = e.target.result.body;
      checkDone();
    };
  }

  attachments.forEach(function (att) {
    if (opts.attachments && opts.include_docs) {
      fetchAttachment(doc, att);
    } else {
      doc._attachments[att].stub = true;
      checkDone();
    }
  });
};

// IDB-specific postprocessing necessary because
// we don't know whether we stored a true Blob or
// a base64-encoded string, and if it's a Blob it
// needs to be read outside of the transaction context
exports.postProcessAttachments = function (results) {
  return utils.Promise.all(results.map(function (row) {
    if (row.doc && row.doc._attachments) {
      var attNames = Object.keys(row.doc._attachments);
      return utils.Promise.all(attNames.map(function (att) {
        var attObj = row.doc._attachments[att];
        if (!('body' in attObj)) { // already processed
          return;
        }
        var body = attObj.body;
        var type = attObj.content_type;
        return new utils.Promise(function (resolve) {
          exports.readBlobData(body, type, true, function (base64) {
            row.doc._attachments[att] = utils.extend(
              utils.pick(attObj, ['digest', 'content_type']),
              {data: base64}
            );
            resolve();
          });
        });
      }));
    }
  }));
};

exports.compactRevs = function (revs, docId, txn) {

  var possiblyOrphanedDigests = [];
  var seqStore = txn.objectStore(constants.BY_SEQ_STORE);
  var attStore = txn.objectStore(constants.ATTACH_STORE);
  var attAndSeqStore = txn.objectStore(constants.ATTACH_AND_SEQ_STORE);
  var count = revs.length;

  function checkDone() {
    count--;
    if (!count) { // done processing all revs
      deleteOrphanedAttachments();
    }
  }

  function deleteOrphanedAttachments() {
    if (!possiblyOrphanedDigests.length) {
      return;
    }
    possiblyOrphanedDigests.forEach(function (digest) {
      var countReq = attAndSeqStore.index('digestSeq').count(
        IDBKeyRange.bound(
          digest + '::', digest + '::\uffff', false, false));
      countReq.onsuccess = function (e) {
        var count = e.target.result;
        if (!count) {
          // orphaned
          attStore["delete"](digest);
        }
      };
    });
  }

  revs.forEach(function (rev) {
    var index = seqStore.index('_doc_id_rev');
    var key = docId + "::" + rev;
    index.getKey(key).onsuccess = function (e) {
      var seq = e.target.result;
      if (typeof seq !== 'number') {
        return checkDone();
      }
      seqStore["delete"](seq);

      var cursor = attAndSeqStore.index('seq')
        .openCursor(IDBKeyRange.only(seq));

      cursor.onsuccess = function (event) {
        var cursor = event.target.result;
        if (cursor) {
          var digest = cursor.value.digestSeq.split('::')[0];
          possiblyOrphanedDigests.push(digest);
          attAndSeqStore["delete"](cursor.primaryKey);
          cursor["continue"]();
        } else { // done
          checkDone();
        }
      };
    };
  });
};

exports.openTransactionSafely = function (idb, stores, mode) {
  try {
    return {
      txn: idb.transaction(stores, mode)
    };
  } catch (err) {
    return {
      error: err
    };
  }
};
}).call(this,_dereq_(37))
},{}],7:[function(_dereq_,module,exports){
(function (process){
'use strict';

var utils = _dereq_(32);
var merge = _dereq_(27);
var errors = _dereq_(19);
var idbUtils = _dereq_(6);
var idbConstants = _dereq_(5);
var idbBulkDocs = _dereq_(4);
var checkBlobSupport = _dereq_(3);

var ADAPTER_VERSION = idbConstants.ADAPTER_VERSION;
var ATTACH_AND_SEQ_STORE = idbConstants.ATTACH_AND_SEQ_STORE;
var ATTACH_STORE = idbConstants.ATTACH_STORE;
var BY_SEQ_STORE = idbConstants.BY_SEQ_STORE;
var DETECT_BLOB_SUPPORT_STORE = idbConstants.DETECT_BLOB_SUPPORT_STORE;
var DOC_STORE = idbConstants.DOC_STORE;
var LOCAL_STORE = idbConstants.LOCAL_STORE;
var META_STORE = idbConstants.META_STORE;

var applyNext = idbUtils.applyNext;
var compactRevs = idbUtils.compactRevs;
var decodeDoc = idbUtils.decodeDoc;
var decodeMetadata = idbUtils.decodeMetadata;
var encodeMetadata = idbUtils.encodeMetadata;
var fetchAttachmentsIfNecessary = idbUtils.fetchAttachmentsIfNecessary;
var idbError = idbUtils.idbError;
var postProcessAttachments = idbUtils.postProcessAttachments;
var readBlobData = idbUtils.readBlobData;
var taskQueue = idbUtils.taskQueue;
var openTransactionSafely = idbUtils.openTransactionSafely;

var cachedDBs = {};
var blobSupportPromise;

function IdbPouch(opts, callback) {
  var api = this;

  taskQueue.queue.push({
    action: function (thisCallback) {
      init(api, opts, thisCallback);
    },
    callback: callback
  });
  applyNext();
}

function init(api, opts, callback) {

  var name = opts.name;

  var instanceId = null;
  var idStored = false;
  var idb = null;
  api._docCount = -1;
  api._blobSupport = null;
  api._name = name;

  // called when creating a fresh new database
  function createSchema(db) {
    var docStore = db.createObjectStore(DOC_STORE, {keyPath : 'id'});
    db.createObjectStore(BY_SEQ_STORE, {autoIncrement: true})
      .createIndex('_doc_id_rev', '_doc_id_rev', {unique: true});
    db.createObjectStore(ATTACH_STORE, {keyPath: 'digest'});
    db.createObjectStore(META_STORE, {keyPath: 'id', autoIncrement: false});
    db.createObjectStore(DETECT_BLOB_SUPPORT_STORE);

    // added in v2
    docStore.createIndex('deletedOrLocal', 'deletedOrLocal', {unique : false});

    // added in v3
    db.createObjectStore(LOCAL_STORE, {keyPath: '_id'});

    // added in v4
    var attAndSeqStore = db.createObjectStore(ATTACH_AND_SEQ_STORE,
      {autoIncrement: true});
    attAndSeqStore.createIndex('seq', 'seq');
    attAndSeqStore.createIndex('digestSeq', 'digestSeq', {unique: true});
  }

  // migration to version 2
  // unfortunately "deletedOrLocal" is a misnomer now that we no longer
  // store local docs in the main doc-store, but whaddyagonnado
  function addDeletedOrLocalIndex(txn, callback) {
    var docStore = txn.objectStore(DOC_STORE);
    docStore.createIndex('deletedOrLocal', 'deletedOrLocal', {unique : false});

    docStore.openCursor().onsuccess = function (event) {
      var cursor = event.target.result;
      if (cursor) {
        var metadata = cursor.value;
        var deleted = utils.isDeleted(metadata);
        metadata.deletedOrLocal = deleted ? "1" : "0";
        docStore.put(metadata);
        cursor["continue"]();
      } else {
        callback();
      }
    };
  }

  // migration to version 3 (part 1)
  function createLocalStoreSchema(db) {
    db.createObjectStore(LOCAL_STORE, {keyPath: '_id'})
      .createIndex('_doc_id_rev', '_doc_id_rev', {unique: true});
  }

  // migration to version 3 (part 2)
  function migrateLocalStore(txn, cb) {
    var localStore = txn.objectStore(LOCAL_STORE);
    var docStore = txn.objectStore(DOC_STORE);
    var seqStore = txn.objectStore(BY_SEQ_STORE);

    var cursor = docStore.openCursor();
    cursor.onsuccess = function (event) {
      var cursor = event.target.result;
      if (cursor) {
        var metadata = cursor.value;
        var docId = metadata.id;
        var local = utils.isLocalId(docId);
        var rev = merge.winningRev(metadata);
        if (local) {
          var docIdRev = docId + "::" + rev;
          // remove all seq entries
          // associated with this docId
          var start = docId + "::";
          var end = docId + "::~";
          var index = seqStore.index('_doc_id_rev');
          var range = IDBKeyRange.bound(start, end, false, false);
          var seqCursor = index.openCursor(range);
          seqCursor.onsuccess = function (e) {
            seqCursor = e.target.result;
            if (!seqCursor) {
              // done
              docStore["delete"](cursor.primaryKey);
              cursor["continue"]();
            } else {
              var data = seqCursor.value;
              if (data._doc_id_rev === docIdRev) {
                localStore.put(data);
              }
              seqStore["delete"](seqCursor.primaryKey);
              seqCursor["continue"]();
            }
          };
        } else {
          cursor["continue"]();
        }
      } else if (cb) {
        cb();
      }
    };
  }

  // migration to version 4 (part 1)
  function addAttachAndSeqStore(db) {
    var attAndSeqStore = db.createObjectStore(ATTACH_AND_SEQ_STORE,
      {autoIncrement: true});
    attAndSeqStore.createIndex('seq', 'seq');
    attAndSeqStore.createIndex('digestSeq', 'digestSeq', {unique: true});
  }

  // migration to version 4 (part 2)
  function migrateAttsAndSeqs(txn, callback) {
    var seqStore = txn.objectStore(BY_SEQ_STORE);
    var attStore = txn.objectStore(ATTACH_STORE);
    var attAndSeqStore = txn.objectStore(ATTACH_AND_SEQ_STORE);

    // need to actually populate the table. this is the expensive part,
    // so as an optimization, check first that this database even
    // contains attachments
    var req = attStore.count();
    req.onsuccess = function (e) {
      var count = e.target.result;
      if (!count) {
        return callback(); // done
      }

      seqStore.openCursor().onsuccess = function (e) {
        var cursor = e.target.result;
        if (!cursor) {
          return callback(); // done
        }
        var doc = cursor.value;
        var seq = cursor.primaryKey;
        var atts = Object.keys(doc._attachments || {});
        var digestMap = {};
        for (var j = 0; j < atts.length; j++) {
          var att = doc._attachments[atts[j]];
          digestMap[att.digest] = true; // uniq digests, just in case
        }
        var digests = Object.keys(digestMap);
        for (j = 0; j < digests.length; j++) {
          var digest = digests[j];
          attAndSeqStore.put({
            seq: seq,
            digestSeq: digest + '::' + seq
          });
        }
        cursor["continue"]();
      };
    };
  }

  // migration to version 5
  // Instead of relying on on-the-fly migration of metadata,
  // this brings the doc-store to its modern form:
  // - metadata.winningrev
  // - metadata.seq
  // - stringify the metadata when storing it
  function migrateMetadata(txn) {

    function decodeMetadataCompat(storedObject) {
      if (!storedObject.data) {
        // old format, when we didn't store it stringified
        storedObject.deletedOrLocal = storedObject.deletedOrLocal === '1';
        return storedObject;
      }
      return decodeMetadata(storedObject);
    }

    // ensure that every metadata has a winningRev and seq,
    // which was previously created on-the-fly but better to migrate
    var bySeqStore = txn.objectStore(BY_SEQ_STORE);
    var docStore = txn.objectStore(DOC_STORE);
    var cursor = docStore.openCursor();
    cursor.onsuccess = function (e) {
      var cursor = e.target.result;
      if (!cursor) {
        return; // done
      }
      var metadata = decodeMetadataCompat(cursor.value);

      metadata.winningRev = metadata.winningRev || merge.winningRev(metadata);

      function fetchMetadataSeq() {
        // metadata.seq was added post-3.2.0, so if it's missing,
        // we need to fetch it manually
        var start = metadata.id + '::';
        var end = metadata.id + '::\uffff';
        var req = bySeqStore.index('_doc_id_rev').openCursor(
          IDBKeyRange.bound(start, end));

        var metadataSeq = 0;
        req.onsuccess = function (e) {
          var cursor = e.target.result;
          if (!cursor) {
            metadata.seq = metadataSeq;
            return onGetMetadataSeq();
          }
          var seq = cursor.primaryKey;
          if (seq > metadataSeq) {
            metadataSeq = seq;
          }
          cursor["continue"]();
        };
      }

      function onGetMetadataSeq() {
        var metadataToStore = encodeMetadata(metadata,
          metadata.winningRev, metadata.deletedOrLocal);

        var req = docStore.put(metadataToStore);
        req.onsuccess = function () {
          cursor["continue"]();
        };
      }

      if (metadata.seq) {
        return onGetMetadataSeq();
      }

      fetchMetadataSeq();
    };

  }

  api.type = function () {
    return 'idb';
  };

  api._id = utils.toPromise(function (callback) {
    callback(null, instanceId);
  });

  api._bulkDocs = function idb_bulkDocs(req, opts, callback) {
    idbBulkDocs(req, opts, api, idb, IdbPouch.Changes, callback);
  };

  // First we look up the metadata in the ids database, then we fetch the
  // current revision(s) from the by sequence store
  api._get = function idb_get(id, opts, callback) {
    var doc;
    var metadata;
    var err;
    var txn;
    opts = utils.clone(opts);
    if (opts.ctx) {
      txn = opts.ctx;
    } else {
      var txnResult = openTransactionSafely(idb,
        [DOC_STORE, BY_SEQ_STORE, ATTACH_STORE], 'readonly');
      if (txnResult.error) {
        return callback(txnResult.error);
      }
      txn = txnResult.txn;
    }

    function finish() {
      callback(err, {doc: doc, metadata: metadata, ctx: txn});
    }

    txn.objectStore(DOC_STORE).get(id).onsuccess = function (e) {
      metadata = decodeMetadata(e.target.result);
      // we can determine the result here if:
      // 1. there is no such document
      // 2. the document is deleted and we don't ask about specific rev
      // When we ask with opts.rev we expect the answer to be either
      // doc (possibly with _deleted=true) or missing error
      if (!metadata) {
        err = errors.error(errors.MISSING_DOC, 'missing');
        return finish();
      }
      if (utils.isDeleted(metadata) && !opts.rev) {
        err = errors.error(errors.MISSING_DOC, "deleted");
        return finish();
      }
      var objectStore = txn.objectStore(BY_SEQ_STORE);

      var rev = opts.rev || metadata.winningRev;
      var key = metadata.id + '::' + rev;

      objectStore.index('_doc_id_rev').get(key).onsuccess = function (e) {
        doc = e.target.result;
        if (doc) {
          doc = decodeDoc(doc);
        }
        if (!doc) {
          err = errors.error(errors.MISSING_DOC, 'missing');
          return finish();
        }
        finish();
      };
    };
  };

  api._getAttachment = function (attachment, opts, callback) {
    var txn;
    opts = utils.clone(opts);
    if (opts.ctx) {
      txn = opts.ctx;
    } else {
      var txnResult = openTransactionSafely(idb,
        [DOC_STORE, BY_SEQ_STORE, ATTACH_STORE], 'readonly');
      if (txnResult.error) {
        return callback(txnResult.error);
      }
      txn = txnResult.txn;
    }
    var digest = attachment.digest;
    var type = attachment.content_type;

    txn.objectStore(ATTACH_STORE).get(digest).onsuccess = function (e) {
      var body = e.target.result.body;
      readBlobData(body, type, opts.encode, function (blobData) {
        callback(null, blobData);
      });
    };
  };

  function allDocsQuery(totalRows, opts, callback) {
    var start = 'startkey' in opts ? opts.startkey : false;
    var end = 'endkey' in opts ? opts.endkey : false;
    var key = 'key' in opts ? opts.key : false;
    var skip = opts.skip || 0;
    var limit = typeof opts.limit === 'number' ? opts.limit : -1;
    var inclusiveEnd = opts.inclusive_end !== false;
    var descending = 'descending' in opts && opts.descending ? 'prev' : null;

    var manualDescEnd = false;
    if (descending && start && end) {
      // unfortunately IDB has a quirk where IDBKeyRange.bound is invalid if the
      // start is less than the end, even in descending mode.  Best bet
      // is just to handle it manually in that case.
      manualDescEnd = end;
      end = false;
    }

    var keyRange = null;
    try {
      if (start && end) {
        keyRange = IDBKeyRange.bound(start, end, false, !inclusiveEnd);
      } else if (start) {
        if (descending) {
          keyRange = IDBKeyRange.upperBound(start);
        } else {
          keyRange = IDBKeyRange.lowerBound(start);
        }
      } else if (end) {
        if (descending) {
          keyRange = IDBKeyRange.lowerBound(end, !inclusiveEnd);
        } else {
          keyRange = IDBKeyRange.upperBound(end, !inclusiveEnd);
        }
      } else if (key) {
        keyRange = IDBKeyRange.only(key);
      }
    } catch (e) {
      if (e.name === "DataError" && e.code === 0) {
        // data error, start is less than end
        return callback(null, {
          total_rows : totalRows,
          offset : opts.skip,
          rows : []
        });
      } else {
        return callback(errors.error(errors.IDB_ERROR, e.name, e.message));
      }
    }

    var stores = [DOC_STORE, BY_SEQ_STORE];
    if (opts.attachments) {
      stores.push(ATTACH_STORE);
    }
    var txnResult = openTransactionSafely(idb, stores, 'readonly');
    if (txnResult.error) {
      return callback(txnResult.error);
    }
    var transaction = txnResult.txn;

    function onResultsReady() {
      callback(null, {
        total_rows: totalRows,
        offset: opts.skip,
        rows: results
      });
    }

    transaction.oncomplete = function () {
      if (opts.attachments) {
        postProcessAttachments(results).then(onResultsReady);
      } else {
        onResultsReady();
      }
    };

    var oStore = transaction.objectStore(DOC_STORE);
    var oCursor = descending ? oStore.openCursor(keyRange, descending)
      : oStore.openCursor(keyRange);
    var results = [];
    oCursor.onsuccess = function (e) {
      if (!e.target.result) {
        return;
      }
      var cursor = e.target.result;
      var metadata = decodeMetadata(cursor.value);
      var winningRev = metadata.winningRev;

      function allDocsInner(metadata, data) {
        var doc = {
          id: metadata.id,
          key: metadata.id,
          value: {
            rev: winningRev
          }
        };
        if (opts.include_docs) {
          doc.doc = data;
          if (opts.conflicts) {
            doc.doc._conflicts = merge.collectConflicts(metadata);
          }
          fetchAttachmentsIfNecessary(doc.doc, opts, transaction);
        }
        var deleted = utils.isDeleted(metadata, winningRev);
        if (opts.deleted === 'ok') {
          // deleted docs are okay with keys_requests
          if (deleted) {
            doc.value.deleted = true;
            doc.doc = null;
          }
          results.push(doc);
        } else if (!deleted && skip-- <= 0) {
          if (manualDescEnd) {
            if (inclusiveEnd && doc.key < manualDescEnd) {
              return;
            } else if (!inclusiveEnd && doc.key <= manualDescEnd) {
              return;
            }
          }
          results.push(doc);
          if (--limit === 0) {
            return;
          }
        }
        cursor["continue"]();
      }

      if (!opts.include_docs) {
        allDocsInner(metadata);
      } else {
        var index = transaction.objectStore(BY_SEQ_STORE).index('_doc_id_rev');
        var key = metadata.id + "::" + winningRev;
        index.get(key).onsuccess = function (event) {
          allDocsInner(decodeMetadata(cursor.value),
            decodeDoc(event.target.result));
        };
      }
    };
  }

  function countDocs(callback) {
    if (api._docCount !== -1) {
      return callback(null, api._docCount);
    }

    var count;
    var txnResult = openTransactionSafely(idb, [DOC_STORE], 'readonly');
    if (txnResult.error) {
      return callback(txnResult.error);
    }
    var txn = txnResult.txn;
    var index = txn.objectStore(DOC_STORE).index('deletedOrLocal');
    index.count(IDBKeyRange.only("0")).onsuccess = function (e) {
      count = e.target.result;
    };
    txn.onerror = idbError(callback);
    txn.oncomplete = function () {
      api._docCount = count;
      callback(null, api._docCount);
    };
  }

  api._allDocs = function idb_allDocs(opts, callback) {

    // first count the total_rows
    countDocs(function (err, totalRows) {
      if (err) {
        return callback(err);
      }
      if (opts.limit === 0) {
        return callback(null, {
          total_rows : totalRows,
          offset : opts.skip,
          rows : []
        });
      }
      allDocsQuery(totalRows, opts, callback);
    });
  };

  api._info = function idb_info(callback) {

    countDocs(function (err, count) {
      if (err) {
        return callback(err);
      }
      if (idb === null || !cachedDBs[api._name]) {
        var error = new Error('db isn\'t open');
        error.id = 'idbNull';
        return callback(error);
      }
      var updateSeq = 0;
      var txnResult = openTransactionSafely(idb, [BY_SEQ_STORE], 'readonly');
      if (txnResult.error) {
        return callback(txnResult.error);
      }
      var txn = txnResult.txn;
      txn.objectStore(BY_SEQ_STORE).openCursor(null, "prev").onsuccess =
        function (event) {
        var cursor = event.target.result;
        if (cursor) {
          updateSeq = cursor.key;
        } else {
          updateSeq = 0;
        }
      };

      txn.oncomplete = function () {
        callback(null, {
          doc_count: count,
          update_seq: updateSeq
        });
      };
    });
  };

  api._changes = function (opts) {
    opts = utils.clone(opts);

    if (opts.continuous) {
      var id = name + ':' + utils.uuid();
      IdbPouch.Changes.addListener(name, id, api, opts);
      IdbPouch.Changes.notify(name);
      return {
        cancel: function () {
          IdbPouch.Changes.removeListener(name, id);
        }
      };
    }

    var docIds = opts.doc_ids && new utils.Set(opts.doc_ids);
    var descending = opts.descending ? 'prev' : null;

    opts.since = opts.since || 0;
    var lastSeq = opts.since;

    var limit = 'limit' in opts ? opts.limit : -1;
    if (limit === 0) {
      limit = 1; // per CouchDB _changes spec
    }
    var returnDocs;
    if ('returnDocs' in opts) {
      returnDocs = opts.returnDocs;
    } else {
      returnDocs = true;
    }

    var results = [];
    var numResults = 0;
    var filter = utils.filterChange(opts);
    var docIdsToMetadata = new utils.Map();

    var txn;
    var bySeqStore;
    var docStore;

    function onGetCursor(cursor) {

      var doc = decodeDoc(cursor.value);
      var seq = cursor.key;

      lastSeq = seq;

      if (docIds && !docIds.has(doc._id)) {
        return cursor["continue"]();
      }

      var metadata;

      function onGetMetadata() {
        if (metadata.seq !== seq) {
          // some other seq is later
          return cursor["continue"]();
        }

        if (metadata.winningRev === doc._rev) {
          return onGetWinningDoc(doc);
        }

        fetchWinningDoc();
      }

      function fetchWinningDoc() {
        var docIdRev = doc._id + '::' + metadata.winningRev;
        var req = bySeqStore.index('_doc_id_rev').openCursor(
          IDBKeyRange.bound(docIdRev, docIdRev + '\uffff'));
        req.onsuccess = function (e) {
          onGetWinningDoc(decodeDoc(e.target.result.value));
        };
      }

      function onGetWinningDoc(winningDoc) {

        var change = opts.processChange(winningDoc, metadata, opts);
        change.seq = metadata.seq;
        if (filter(change)) {
          numResults++;
          if (returnDocs) {
            results.push(change);
          }
          // process the attachment immediately
          // for the benefit of live listeners
          if (opts.attachments && opts.include_docs) {
            fetchAttachmentsIfNecessary(winningDoc, opts, txn, function () {
              postProcessAttachments([change]).then(function () {
                opts.onChange(change);
              });
            });
          } else {
            opts.onChange(change);
          }
        }
        if (numResults !== limit) {
          cursor["continue"]();
        }
      }

      metadata = docIdsToMetadata.get(doc._id);
      if (metadata) { // cached
        return onGetMetadata();
      }
      // metadata not cached, have to go fetch it
      docStore.get(doc._id).onsuccess = function (event) {
        metadata = decodeMetadata(event.target.result);
        docIdsToMetadata.set(doc._id, metadata);
        onGetMetadata();
      };
    }

    function onsuccess(event) {
      var cursor = event.target.result;

      if (!cursor) {
        return;
      }
      onGetCursor(cursor);
    }

    function fetchChanges() {
      var objectStores = [DOC_STORE, BY_SEQ_STORE];
      if (opts.attachments) {
        objectStores.push(ATTACH_STORE);
      }
      var txnResult = openTransactionSafely(idb, objectStores, 'readonly');
      if (txnResult.error) {
        return opts.complete(txnResult.error);
      }
      txn = txnResult.txn;
      txn.onerror = idbError(opts.complete);
      txn.oncomplete = onTxnComplete;

      bySeqStore = txn.objectStore(BY_SEQ_STORE);
      docStore = txn.objectStore(DOC_STORE);

      var req;

      if (descending) {
        req = bySeqStore.openCursor(

          null, descending);
      } else {
        req = bySeqStore.openCursor(
          IDBKeyRange.lowerBound(opts.since, true));
      }

      req.onsuccess = onsuccess;
    }

    fetchChanges();

    function onTxnComplete() {

      function finish() {
        opts.complete(null, {
          results: results,
          last_seq: lastSeq
        });
      }

      if (!opts.continuous && opts.attachments) {
        // cannot guarantee that postProcessing was already done,
        // so do it again
        postProcessAttachments(results).then(finish);
      } else {
        finish();
      }
    }
  };

  api._close = function (callback) {
    if (idb === null) {
      return callback(errors.error(errors.NOT_OPEN));
    }

    // https://developer.mozilla.org/en-US/docs/IndexedDB/IDBDatabase#close
    // "Returns immediately and closes the connection in a separate thread..."
    idb.close();
    delete cachedDBs[name];
    idb = null;
    callback();
  };

  api._getRevisionTree = function (docId, callback) {
    var txnResult = openTransactionSafely(idb, [DOC_STORE], 'readonly');
    if (txnResult.error) {
      return callback(txnResult.error);
    }
    var txn = txnResult.txn;
    var req = txn.objectStore(DOC_STORE).get(docId);
    req.onsuccess = function (event) {
      var doc = decodeMetadata(event.target.result);
      if (!doc) {
        callback(errors.error(errors.MISSING_DOC));
      } else {
        callback(null, doc.rev_tree);
      }
    };
  };

  // This function removes revisions of document docId
  // which are listed in revs and sets this document
  // revision to to rev_tree
  api._doCompaction = function (docId, revs, callback) {
    var stores = [
      DOC_STORE,
      BY_SEQ_STORE,
      ATTACH_STORE,
      ATTACH_AND_SEQ_STORE
    ];
    var txnResult = openTransactionSafely(idb, stores, 'readwrite');
    if (txnResult.error) {
      return callback(txnResult.error);
    }
    var txn = txnResult.txn;

    var docStore = txn.objectStore(DOC_STORE);

    docStore.get(docId).onsuccess = function (event) {
      var metadata = decodeMetadata(event.target.result);
      merge.traverseRevTree(metadata.rev_tree, function (isLeaf, pos,
                                                         revHash, ctx, opts) {
        var rev = pos + '-' + revHash;
        if (revs.indexOf(rev) !== -1) {
          opts.status = 'missing';
        }
      });
      compactRevs(revs, docId, txn);
      var winningRev = metadata.winningRev;
      var deleted = metadata.deletedOrLocal;
      txn.objectStore(DOC_STORE).put(
        encodeMetadata(metadata, winningRev, deleted));
    };
    txn.onerror = idbError(callback);
    txn.oncomplete = function () {
      utils.call(callback);
    };
  };


  api._getLocal = function (id, callback) {
    var txnResult = openTransactionSafely(idb, [LOCAL_STORE], 'readonly');
    if (txnResult.error) {
      return callback(txnResult.error);
    }
    var tx = txnResult.txn;
    var req = tx.objectStore(LOCAL_STORE).get(id);

    req.onerror = idbError(callback);
    req.onsuccess = function (e) {
      var doc = e.target.result;
      if (!doc) {
        callback(errors.error(errors.MISSING_DOC));
      } else {
        delete doc['_doc_id_rev']; // for backwards compat
        callback(null, doc);
      }
    };
  };

  api._putLocal = function (doc, opts, callback) {
    if (typeof opts === 'function') {
      callback = opts;
      opts = {};
    }
    delete doc._revisions; // ignore this, trust the rev
    var oldRev = doc._rev;
    var id = doc._id;
    if (!oldRev) {
      doc._rev = '0-1';
    } else {
      doc._rev = '0-' + (parseInt(oldRev.split('-')[1], 10) + 1);
    }

    var tx = opts.ctx;
    var ret;
    if (!tx) {
      var txnResult = openTransactionSafely(idb, [LOCAL_STORE], 'readwrite');
      if (txnResult.error) {
        return callback(txnResult.error);
      }
      tx = txnResult.txn;
      tx.onerror = idbError(callback);
      tx.oncomplete = function () {
        if (ret) {
          callback(null, ret);
        }
      };
    }

    var oStore = tx.objectStore(LOCAL_STORE);
    var req;
    if (oldRev) {
      req = oStore.get(id);
      req.onsuccess = function (e) {
        var oldDoc = e.target.result;
        if (!oldDoc || oldDoc._rev !== oldRev) {
          callback(errors.error(errors.REV_CONFLICT));
        } else { // update
          var req = oStore.put(doc);
          req.onsuccess = function () {
            ret = {ok: true, id: doc._id, rev: doc._rev};
            if (opts.ctx) { // return immediately
              callback(null, ret);
            }
          };
        }
      };
    } else { // new doc
      req = oStore.add(doc);
      req.onerror = function (e) {
        // constraint error, already exists
        callback(errors.error(errors.REV_CONFLICT));
        e.preventDefault(); // avoid transaction abort
        e.stopPropagation(); // avoid transaction onerror
      };
      req.onsuccess = function () {
        ret = {ok: true, id: doc._id, rev: doc._rev};
        if (opts.ctx) { // return immediately
          callback(null, ret);
        }
      };
    }
  };

  api._removeLocal = function (doc, callback) {
    var txnResult = openTransactionSafely(idb, [LOCAL_STORE], 'readwrite');
    if (txnResult.error) {
      return callback(txnResult.error);
    }
    var tx = txnResult.txn;
    var ret;
    tx.oncomplete = function () {
      if (ret) {
        callback(null, ret);
      }
    };
    var id = doc._id;
    var oStore = tx.objectStore(LOCAL_STORE);
    var req = oStore.get(id);

    req.onerror = idbError(callback);
    req.onsuccess = function (e) {
      var oldDoc = e.target.result;
      if (!oldDoc || oldDoc._rev !== doc._rev) {
        callback(errors.error(errors.MISSING_DOC));
      } else {
        oStore["delete"](id);
        ret = {ok: true, id: id, rev: '0-0'};
      }
    };
  };

  var cached = cachedDBs[name];

  if (cached) {
    idb = cached.idb;
    instanceId = cached.instanceId;
    api._blobSupport = cached.blobSupport;
    process.nextTick(function () {
      callback(null, api);
    });
    return;
  }

  var req = indexedDB.open(name, ADAPTER_VERSION);

  if (!('openReqList' in IdbPouch)) {
    IdbPouch.openReqList = {};
  }
  IdbPouch.openReqList[name] = req;

  req.onupgradeneeded = function (e) {
    var db = e.target.result;
    if (e.oldVersion < 1) {
      return createSchema(db); // new db, initial schema
    }
    // do migrations

    var txn = e.currentTarget.transaction;
    // these migrations have to be done in this function, before
    // control is returned to the event loop, because IndexedDB

    if (e.oldVersion < 3) {
      createLocalStoreSchema(db); // v2 -> v3
    }
    if (e.oldVersion < 4) {
      addAttachAndSeqStore(db); // v3 -> v4
    }

    var migrations = [
      addDeletedOrLocalIndex, // v1 -> v2
      migrateLocalStore,      // v2 -> v3
      migrateAttsAndSeqs,     // v3 -> v4
      migrateMetadata         // v4 -> v5
    ];

    var i = e.oldVersion;

    function next() {
      var migration = migrations[i - 1];
      i++;
      if (migration) {
        migration(txn, next);
      }
    }

    next();
  };

  req.onsuccess = function (e) {

    idb = e.target.result;

    idb.onversionchange = function () {
      idb.close();
      delete cachedDBs[name];
    };
    idb.onabort = function () {
      idb.close();
      delete cachedDBs[name];
    };

    var txn = idb.transaction([META_STORE, DETECT_BLOB_SUPPORT_STORE],
      'readwrite');

    var req = txn.objectStore(META_STORE).get(META_STORE);

    req.onsuccess = function (e) {

      var checkSetupComplete = function () {
        if (api._blobSupport === null || !idStored) {
          return;
        } else {
          cachedDBs[name] = {
            idb: idb,
            instanceId: instanceId,
            blobSupport: api._blobSupport,
            loaded: true
          };
          callback(null, api);
        }
      };

      var meta = e.target.result || {id: META_STORE};
      if (name  + '_id' in meta) {
        instanceId = meta[name + '_id'];
        idStored = true;
        checkSetupComplete();
      } else {
        instanceId = utils.uuid();
        meta[name + '_id'] = instanceId;
        txn.objectStore(META_STORE).put(meta).onsuccess = function () {
          idStored = true;
          checkSetupComplete();
        };
      }

      if (!blobSupportPromise) {
        // make sure blob support is only checked once
        blobSupportPromise = checkBlobSupport(txn, idb);
      }

      blobSupportPromise.then(function (val) {
        api._blobSupport = val;
        checkSetupComplete();
      });
    };
  };

  req.onerror = idbError(callback);

}

IdbPouch.valid = function () {
  // Issue #2533, we finally gave up on doing bug
  // detection instead of browser sniffing. Safari brought us
  // to our knees.
  var isSafari = typeof openDatabase !== 'undefined' &&
    /(Safari|iPhone|iPad|iPod)/.test(navigator.userAgent) &&
    !/Chrome/.test(navigator.userAgent);

  // some outdated implementations of IDB that appear on Samsung
  // and HTC Android devices <4.4 are missing IDBKeyRange
  return !isSafari && typeof indexedDB !== 'undefined' &&
    typeof IDBKeyRange !== 'undefined';
};

function destroy(name, opts, callback) {
  if (!('openReqList' in IdbPouch)) {
    IdbPouch.openReqList = {};
  }
  IdbPouch.Changes.removeAllListeners(name);

  //Close open request for "name" database to fix ie delay.
  if (IdbPouch.openReqList[name] && IdbPouch.openReqList[name].result) {
    IdbPouch.openReqList[name].result.close();
    delete cachedDBs[name];
  }
  var req = indexedDB.deleteDatabase(name);

  req.onsuccess = function () {
    //Remove open request from the list.
    if (IdbPouch.openReqList[name]) {
      IdbPouch.openReqList[name] = null;
    }
    if (utils.hasLocalStorage() && (name in localStorage)) {
      delete localStorage[name];
    }
    callback(null, { 'ok': true });
  };

  req.onerror = idbError(callback);
}

IdbPouch.destroy = utils.toPromise(function (name, opts, callback) {
  taskQueue.queue.push({
    action: function (thisCallback) {
      destroy(name, opts, thisCallback);
    },
    callback: callback
  });
  applyNext();
});

IdbPouch.Changes = new utils.Changes();

module.exports = IdbPouch;

}).call(this,_dereq_(37))
},{}],8:[function(_dereq_,module,exports){
module.exports = ['idb', 'websql'];
},{}],9:[function(_dereq_,module,exports){
'use strict';

var utils = _dereq_(32);
var errors = _dereq_(19);

var websqlUtils = _dereq_(11);
var websqlConstants = _dereq_(10);

var DOC_STORE = websqlConstants.DOC_STORE;
var BY_SEQ_STORE = websqlConstants.BY_SEQ_STORE;
var ATTACH_STORE = websqlConstants.ATTACH_STORE;
var ATTACH_AND_SEQ_STORE = websqlConstants.ATTACH_AND_SEQ_STORE;

var select = websqlUtils.select;
var stringifyDoc = websqlUtils.stringifyDoc;
var compactRevs = websqlUtils.compactRevs;
var unknownError = websqlUtils.unknownError;

function websqlBulkDocs(req, opts, api, db, Changes, callback) {
  var newEdits = opts.new_edits;
  var userDocs = req.docs;

  // Parse the docs, give them a sequence number for the result
  var docInfos = userDocs.map(function (doc) {
    if (doc._id && utils.isLocalId(doc._id)) {
      return doc;
    }
    var newDoc = utils.parseDoc(doc, newEdits);
    return newDoc;
  });

  var docInfoErrors = docInfos.filter(function (docInfo) {
    return docInfo.error;
  });
  if (docInfoErrors.length) {
    return callback(docInfoErrors[0]);
  }

  var tx;
  var results = new Array(docInfos.length);
  var fetchedDocs = new utils.Map();

  var preconditionErrored;
  function complete() {
    if (preconditionErrored) {
      return callback(preconditionErrored);
    }
    Changes.notify(api._name);
    api._docCount = -1; // invalidate
    callback(null, results);
  }

  function verifyAttachment(digest, callback) {
    var sql = 'SELECT count(*) as cnt FROM ' + ATTACH_STORE +
      ' WHERE digest=?';
    tx.executeSql(sql, [digest], function (tx, result) {
      if (result.rows.item(0).cnt === 0) {
        var err = errors.error(errors.MISSING_STUB,
          'unknown stub attachment with digest ' +
          digest);
        callback(err);
      } else {
        callback();
      }
    });
  }

  function verifyAttachments(finish) {
    var digests = [];
    docInfos.forEach(function (docInfo) {
      if (docInfo.data && docInfo.data._attachments) {
        Object.keys(docInfo.data._attachments).forEach(function (filename) {
          var att = docInfo.data._attachments[filename];
          if (att.stub) {
            digests.push(att.digest);
          }
        });
      }
    });
    if (!digests.length) {
      return finish();
    }
    var numDone = 0;
    var err;

    function checkDone() {
      if (++numDone === digests.length) {
        finish(err);
      }
    }
    digests.forEach(function (digest) {
      verifyAttachment(digest, function (attErr) {
        if (attErr && !err) {
          err = attErr;
        }
        checkDone();
      });
    });
  }


  function writeDoc(docInfo, winningRev, deleted, callback, isUpdate,
                    docCount, resultsIdx) {

    function finish() {
      var data = docInfo.data;
      var deletedInt = deleted ? 1 : 0;

      var id = data._id;
      var rev = data._rev;
      var json = stringifyDoc(data);
      var sql = 'INSERT INTO ' + BY_SEQ_STORE +
        ' (doc_id, rev, json, deleted) VALUES (?, ?, ?, ?);';
      var sqlArgs = [id, rev, json, deletedInt];

      // map seqs to attachment digests, which
      // we will need later during compaction
      function insertAttachmentMappings(seq, callback) {
        var attsAdded = 0;
        var attsToAdd = Object.keys(data._attachments || {});

        if (!attsToAdd.length) {
          return callback();
        }
        function checkDone() {
          if (++attsAdded === attsToAdd.length) {
            callback();
          }
          return false; // ack handling a constraint error
        }
        function add(att) {
          var sql = 'INSERT INTO ' + ATTACH_AND_SEQ_STORE +
            ' (digest, seq) VALUES (?,?)';
          var sqlArgs = [data._attachments[att].digest, seq];
          tx.executeSql(sql, sqlArgs, checkDone, checkDone);
          // second callback is for a constaint error, which we ignore
          // because this docid/rev has already been associated with
          // the digest (e.g. when new_edits == false)
        }
        for (var i = 0; i < attsToAdd.length; i++) {
          add(attsToAdd[i]); // do in parallel
        }
      }

      tx.executeSql(sql, sqlArgs, function (tx, result) {
        var seq = result.insertId;
        insertAttachmentMappings(seq, function () {
          dataWritten(tx, seq);
        });
      }, function () {
        // constraint error, recover by updating instead (see #1638)
        var fetchSql = select('seq', BY_SEQ_STORE, null,
          'doc_id=? AND rev=?');
        tx.executeSql(fetchSql, [id, rev], function (tx, res) {
          var seq = res.rows.item(0).seq;
          var sql = 'UPDATE ' + BY_SEQ_STORE +
            ' SET json=?, deleted=? WHERE doc_id=? AND rev=?;';
          var sqlArgs = [json, deletedInt, id, rev];
          tx.executeSql(sql, sqlArgs, function (tx) {
            insertAttachmentMappings(seq, function () {
              dataWritten(tx, seq);
            });
          });
        });
        return false; // ack that we've handled the error
      });
    }

    function collectResults(attachmentErr) {
      if (!err) {
        if (attachmentErr) {
          err = attachmentErr;
          callback(err);
        } else if (recv === attachments.length) {
          finish();
        }
      }
    }

    var err = null;
    var recv = 0;

    docInfo.data._id = docInfo.metadata.id;
    docInfo.data._rev = docInfo.metadata.rev;
    var attachments = Object.keys(docInfo.data._attachments || {});


    if (deleted) {
      docInfo.data._deleted = true;
    }

    function attachmentSaved(err) {
      recv++;
      collectResults(err);
    }

    attachments.forEach(function (key) {
      var att = docInfo.data._attachments[key];
      if (!att.stub) {
        var data = att.data;
        delete att.data;
        var digest = att.digest;
        saveAttachment(digest, data, attachmentSaved);
      } else {
        recv++;
        collectResults();
      }
    });

    if (!attachments.length) {
      finish();
    }

    function autoCompact() {
      if (!isUpdate || !api.auto_compaction) {
        return; // nothing to do
      }
      var id = docInfo.metadata.id;
      var revsToDelete = utils.compactTree(docInfo.metadata);
      compactRevs(revsToDelete, id, tx);
    }

    function dataWritten(tx, seq) {
      autoCompact();
      docInfo.metadata.seq = seq;
      delete docInfo.metadata.rev;

      var sql = isUpdate ?
      'UPDATE ' + DOC_STORE +
      ' SET json=?, max_seq=?, winningseq=' +
      '(SELECT seq FROM ' + BY_SEQ_STORE +
      ' WHERE doc_id=' + DOC_STORE + '.id AND rev=?) WHERE id=?'
        : 'INSERT INTO ' + DOC_STORE +
      ' (id, winningseq, max_seq, json) VALUES (?,?,?,?);';
      var metadataStr = utils.safeJsonStringify(docInfo.metadata);
      var id = docInfo.metadata.id;
      var params = isUpdate ?
        [metadataStr, seq, winningRev, id] :
        [id, seq, seq, metadataStr];
      tx.executeSql(sql, params, function () {
        results[resultsIdx] = {
          ok: true,
          id: docInfo.metadata.id,
          rev: winningRev
        };
        fetchedDocs.set(id, docInfo.metadata);
        callback();
      });
    }
  }

  function processDocs() {
    utils.processDocs(docInfos, api, fetchedDocs,
      tx, results, writeDoc, opts);
  }

  function fetchExistingDocs(callback) {
    if (!docInfos.length) {
      return callback();
    }

    var numFetched = 0;

    function checkDone() {
      if (++numFetched === docInfos.length) {
        callback();
      }
    }

    docInfos.forEach(function (docInfo) {
      if (docInfo._id && utils.isLocalId(docInfo._id)) {
        return checkDone(); // skip local docs
      }
      var id = docInfo.metadata.id;
      tx.executeSql('SELECT json FROM ' + DOC_STORE +
      ' WHERE id = ?', [id], function (tx, result) {
        if (result.rows.length) {
          var metadata = utils.safeJsonParse(result.rows.item(0).json);
          fetchedDocs.set(id, metadata);
        }
        checkDone();
      });
    });
  }

  function saveAttachment(digest, data, callback) {
    var sql = 'SELECT digest FROM ' + ATTACH_STORE + ' WHERE digest=?';
    tx.executeSql(sql, [digest], function (tx, result) {
      if (result.rows.length) { // attachment already exists
        return callback();
      }
      // we could just insert before selecting and catch the error,
      // but my hunch is that it's cheaper not to serialize the blob
      // from JS to C if we don't have to (TODO: confirm this)
      sql = 'INSERT INTO ' + ATTACH_STORE +
      ' (digest, body, escaped) VALUES (?,?,1)';
      tx.executeSql(sql, [digest, websqlUtils.escapeBlob(data)], function () {
        callback();
      }, function () {
        // ignore constaint errors, means it already exists
        callback();
        return false; // ack we handled the error
      });
    });
  }

  utils.preprocessAttachments(docInfos, 'binary', function (err) {
    if (err) {
      return callback(err);
    }
    db.transaction(function (txn) {
      tx = txn;
      verifyAttachments(function (err) {
        if (err) {
          preconditionErrored = err;
        } else {
          fetchExistingDocs(processDocs);
        }
      });
    }, unknownError(callback), complete);
  });
}

module.exports = websqlBulkDocs;

},{}],10:[function(_dereq_,module,exports){
'use strict';

function quote(str) {
  return "'" + str + "'";
}

exports.ADAPTER_VERSION = 7; // used to manage migrations

// The object stores created for each database
// DOC_STORE stores the document meta data, its revision history and state
exports.DOC_STORE = quote('document-store');
// BY_SEQ_STORE stores a particular version of a document, keyed by its
// sequence id
exports.BY_SEQ_STORE = quote('by-sequence');
// Where we store attachments
exports.ATTACH_STORE = quote('attach-store');
exports.LOCAL_STORE = quote('local-store');
exports.META_STORE = quote('metadata-store');
// where we store many-to-many relations between attachment
// digests and seqs
exports.ATTACH_AND_SEQ_STORE = quote('attach-seq-store');


},{}],11:[function(_dereq_,module,exports){
'use strict';

var utils = _dereq_(32);
var errors = _dereq_(19);

var websqlConstants = _dereq_(10);

var BY_SEQ_STORE = websqlConstants.BY_SEQ_STORE;
var ATTACH_STORE = websqlConstants.ATTACH_STORE;
var ATTACH_AND_SEQ_STORE = websqlConstants.ATTACH_AND_SEQ_STORE;

// escapeBlob and unescapeBlob are workarounds for a websql bug:
// https://code.google.com/p/chromium/issues/detail?id=422690
// https://bugs.webkit.org/show_bug.cgi?id=137637
// The goal is to never actually insert the \u0000 character
// in the database.
function escapeBlob(str) {
  return str
    .replace(/\u0002/g, '\u0002\u0002')
    .replace(/\u0001/g, '\u0001\u0002')
    .replace(/\u0000/g, '\u0001\u0001');
}

function unescapeBlob(str) {
  return str
    .replace(/\u0001\u0001/g, '\u0000')
    .replace(/\u0001\u0002/g, '\u0001')
    .replace(/\u0002\u0002/g, '\u0002');
}

function stringifyDoc(doc) {
  // don't bother storing the id/rev. it uses lots of space,
  // in persistent map/reduce especially
  delete doc._id;
  delete doc._rev;
  return JSON.stringify(doc);
}

function unstringifyDoc(doc, id, rev) {
  doc = JSON.parse(doc);
  doc._id = id;
  doc._rev = rev;
  return doc;
}

// question mark groups IN queries, e.g. 3 -> '(?,?,?)'
function qMarks(num) {
  var s = '(';
  while (num--) {
    s += '?';
    if (num) {
      s += ',';
    }
  }
  return s + ')';
}

function select(selector, table, joiner, where, orderBy) {
  return 'SELECT ' + selector + ' FROM ' +
    (typeof table === 'string' ? table : table.join(' JOIN ')) +
    (joiner ? (' ON ' + joiner) : '') +
    (where ? (' WHERE ' +
    (typeof where === 'string' ? where : where.join(' AND '))) : '') +
    (orderBy ? (' ORDER BY ' + orderBy) : '');
}

function compactRevs(revs, docId, tx) {

  if (!revs.length) {
    return;
  }

  var numDone = 0;
  var seqs = [];

  function checkDone() {
    if (++numDone === revs.length) { // done
      deleteOrphans();
    }
  }

  function deleteOrphans() {
    // find orphaned attachment digests

    if (!seqs.length) {
      return;
    }

    var sql = 'SELECT DISTINCT digest AS digest FROM ' +
      ATTACH_AND_SEQ_STORE + ' WHERE seq IN ' + qMarks(seqs.length);

    tx.executeSql(sql, seqs, function (tx, res) {

      var digestsToCheck = [];
      for (var i = 0; i < res.rows.length; i++) {
        digestsToCheck.push(res.rows.item(i).digest);
      }
      if (!digestsToCheck.length) {
        return;
      }

      var sql = 'DELETE FROM ' + ATTACH_AND_SEQ_STORE +
        ' WHERE seq IN (' +
        seqs.map(function () { return '?'; }).join(',') +
        ')';
      tx.executeSql(sql, seqs, function (tx) {

        var sql = 'SELECT digest FROM ' + ATTACH_AND_SEQ_STORE +
          ' WHERE digest IN (' +
          digestsToCheck.map(function () { return '?'; }).join(',') +
          ')';
        tx.executeSql(sql, digestsToCheck, function (tx, res) {
          var nonOrphanedDigests = new utils.Set();
          for (var i = 0; i < res.rows.length; i++) {
            nonOrphanedDigests.add(res.rows.item(i).digest);
          }
          digestsToCheck.forEach(function (digest) {
            if (nonOrphanedDigests.has(digest)) {
              return;
            }
            tx.executeSql(
              'DELETE FROM ' + ATTACH_AND_SEQ_STORE + ' WHERE digest=?',
              [digest]);
            tx.executeSql(
              'DELETE FROM ' + ATTACH_STORE + ' WHERE digest=?', [digest]);
          });
        });
      });
    });
  }

  // update by-seq and attach stores in parallel
  revs.forEach(function (rev) {
    var sql = 'SELECT seq FROM ' + BY_SEQ_STORE +
      ' WHERE doc_id=? AND rev=?';

    tx.executeSql(sql, [docId, rev], function (tx, res) {
      if (!res.rows.length) { // already deleted
        return checkDone();
      }
      var seq = res.rows.item(0).seq;
      seqs.push(seq);

      tx.executeSql(
        'DELETE FROM ' + BY_SEQ_STORE + ' WHERE seq=?', [seq], checkDone);
    });
  });
}

function unknownError(callback) {
  return function (event) {
    // event may actually be a SQLError object, so report is as such
    var errorNameMatch = event && event.constructor.toString()
        .match(/function ([^\(]+)/);
    var errorName = (errorNameMatch && errorNameMatch[1]) || event.type;
    var errorReason = event.target || event.message;
    callback(errors.error(errors.WSQ_ERROR, errorReason, errorName));
  };
}

function getSize(opts) {
  if ('size' in opts) {
    // triggers immediate popup in iOS, fixes #2347
    // e.g. 5000001 asks for 5 MB, 10000001 asks for 10 MB,
    return opts.size * 1000000;
  }
  // In iOS, doesn't matter as long as it's <= 5000000.
  // Except that if you request too much, our tests fail
  // because of the native "do you accept?" popup.
  // In Android <=4.3, this value is actually used as an
  // honest-to-god ceiling for data, so we need to
  // set it to a decently high number.
  var isAndroid = /Android/.test(window.navigator.userAgent);
  return isAndroid ? 5000000 : 1; // in PhantomJS, if you use 0 it will crash
}

module.exports = {
  escapeBlob: escapeBlob,
  unescapeBlob: unescapeBlob,
  stringifyDoc: stringifyDoc,
  unstringifyDoc: unstringifyDoc,
  qMarks: qMarks,
  select: select,
  compactRevs: compactRevs,
  unknownError: unknownError,
  getSize: getSize
};
},{}],12:[function(_dereq_,module,exports){
'use strict';

var utils = _dereq_(32);
var merge = _dereq_(27);
var errors = _dereq_(19);
var parseHexString = _dereq_(21);

var websqlConstants = _dereq_(10);
var websqlUtils = _dereq_(11);
var websqlBulkDocs = _dereq_(9);

var ADAPTER_VERSION = websqlConstants.ADAPTER_VERSION;
var DOC_STORE = websqlConstants.DOC_STORE;
var BY_SEQ_STORE = websqlConstants.BY_SEQ_STORE;
var ATTACH_STORE = websqlConstants.ATTACH_STORE;
var LOCAL_STORE = websqlConstants.LOCAL_STORE;
var META_STORE = websqlConstants.META_STORE;
var ATTACH_AND_SEQ_STORE = websqlConstants.ATTACH_AND_SEQ_STORE;

var qMarks = websqlUtils.qMarks;
var stringifyDoc = websqlUtils.stringifyDoc;
var unstringifyDoc = websqlUtils.unstringifyDoc;
var select = websqlUtils.select;
var compactRevs = websqlUtils.compactRevs;
var unknownError = websqlUtils.unknownError;
var getSize = websqlUtils.getSize;

function fetchAttachmentsIfNecessary(doc, opts, api, txn, cb) {
  var attachments = Object.keys(doc._attachments || {});
  if (!attachments.length) {
    return cb && cb();
  }
  var numDone = 0;

  function checkDone() {
    if (++numDone === attachments.length && cb) {
      cb();
    }
  }

  function fetchAttachment(doc, att) {
    var attObj = doc._attachments[att];
    var attOpts = {encode: true, ctx: txn};
    api._getAttachment(attObj, attOpts, function (_, base64) {
      doc._attachments[att] = utils.extend(
        utils.pick(attObj, ['digest', 'content_type']),
        { data: base64 }
      );
      checkDone();
    });
  }

  attachments.forEach(function (att) {
    if (opts.attachments && opts.include_docs) {
      fetchAttachment(doc, att);
    } else {
      doc._attachments[att].stub = true;
      checkDone();
    }
  });
}

var cachedDatabases = {};

var openDBFunction = (typeof navigator !== 'undefined' &&
      navigator.sqlitePlugin &&
      navigator.sqlitePlugin.openDatabase) ?
    navigator.sqlitePlugin.openDatabase.bind(navigator.sqlitePlugin) :
      (typeof sqlitePlugin !== 'undefined' && sqlitePlugin.openDatabase) ?
    sqlitePlugin.openDatabase.bind(sqlitePlugin) :
      (typeof openDatabase !== 'undefined') ?
    openDatabase :
    null;

function openDB(name, version, desc, size) {
  var db = cachedDatabases[name];
  if (!db) {
    db = cachedDatabases[name] = openDBFunction(name, version, desc, size);
  }
  return db;
}

var POUCH_VERSION = 1;

// these indexes cover the ground for most allDocs queries
var BY_SEQ_STORE_DELETED_INDEX_SQL =
  'CREATE INDEX IF NOT EXISTS \'by-seq-deleted-idx\' ON ' +
  BY_SEQ_STORE + ' (seq, deleted)';
var BY_SEQ_STORE_DOC_ID_REV_INDEX_SQL =
  'CREATE UNIQUE INDEX IF NOT EXISTS \'by-seq-doc-id-rev\' ON ' +
    BY_SEQ_STORE + ' (doc_id, rev)';
var DOC_STORE_WINNINGSEQ_INDEX_SQL =
  'CREATE INDEX IF NOT EXISTS \'doc-winningseq-idx\' ON ' +
  DOC_STORE + ' (winningseq)';
var ATTACH_AND_SEQ_STORE_SEQ_INDEX_SQL =
  'CREATE INDEX IF NOT EXISTS \'attach-seq-seq-idx\' ON ' +
    ATTACH_AND_SEQ_STORE + ' (seq)';
var ATTACH_AND_SEQ_STORE_ATTACH_INDEX_SQL =
  'CREATE UNIQUE INDEX IF NOT EXISTS \'attach-seq-digest-idx\' ON ' +
    ATTACH_AND_SEQ_STORE + ' (digest, seq)';

var DOC_STORE_AND_BY_SEQ_JOINER = BY_SEQ_STORE +
  '.seq = ' + DOC_STORE + '.winningseq';

var SELECT_DOCS = BY_SEQ_STORE + '.seq AS seq, ' +
  BY_SEQ_STORE + '.deleted AS deleted, ' +
  BY_SEQ_STORE + '.json AS data, ' +
  BY_SEQ_STORE + '.rev AS rev, ' +
  DOC_STORE + '.json AS metadata';

function WebSqlPouch(opts, callback) {
  var api = this;
  var instanceId = null;
  var size = getSize(opts);
  var idRequests = [];
  var encoding;

  api._docCount = -1; // cache sqlite count(*) for performance
  api._name = opts.name;

  var db = openDB(api._name, POUCH_VERSION, api._name, size);
  if (!db) {
    return callback(errors.error(errors.UNKNOWN_ERROR));
  } else if (typeof db.readTransaction !== 'function') {
    // doesn't exist in sqlite plugin
    db.readTransaction = db.transaction;
  }

  function dbCreated() {
    // note the db name in case the browser upgrades to idb
    if (utils.hasLocalStorage()) {
      window.localStorage['_pouch__websqldb_' + api._name] = true;
    }
    callback(null, api);
  }

  // In this migration, we added the 'deleted' and 'local' columns to the
  // by-seq and doc store tables.
  // To preserve existing user data, we re-process all the existing JSON
  // and add these values.
  // Called migration2 because it corresponds to adapter version (db_version) #2
  function runMigration2(tx, callback) {
    // index used for the join in the allDocs query
    tx.executeSql(DOC_STORE_WINNINGSEQ_INDEX_SQL);

    tx.executeSql('ALTER TABLE ' + BY_SEQ_STORE +
      ' ADD COLUMN deleted TINYINT(1) DEFAULT 0', [], function () {
      tx.executeSql(BY_SEQ_STORE_DELETED_INDEX_SQL);
      tx.executeSql('ALTER TABLE ' + DOC_STORE +
        ' ADD COLUMN local TINYINT(1) DEFAULT 0', [], function () {
        tx.executeSql('CREATE INDEX IF NOT EXISTS \'doc-store-local-idx\' ON ' +
          DOC_STORE + ' (local, id)');

        var sql = 'SELECT ' + DOC_STORE + '.winningseq AS seq, ' + DOC_STORE +
          '.json AS metadata FROM ' + BY_SEQ_STORE + ' JOIN ' + DOC_STORE +
          ' ON ' + BY_SEQ_STORE + '.seq = ' + DOC_STORE + '.winningseq';

        tx.executeSql(sql, [], function (tx, result) {

          var deleted = [];
          var local = [];

          for (var i = 0; i < result.rows.length; i++) {
            var item = result.rows.item(i);
            var seq = item.seq;
            var metadata = JSON.parse(item.metadata);
            if (utils.isDeleted(metadata)) {
              deleted.push(seq);
            }
            if (utils.isLocalId(metadata.id)) {
              local.push(metadata.id);
            }
          }
          tx.executeSql('UPDATE ' + DOC_STORE + 'SET local = 1 WHERE id IN ' +
            qMarks(local.length), local, function () {
            tx.executeSql('UPDATE ' + BY_SEQ_STORE +
              ' SET deleted = 1 WHERE seq IN ' +
              qMarks(deleted.length), deleted, callback);
          });
        });
      });
    });
  }

  // in this migration, we make all the local docs unversioned
  function runMigration3(tx, callback) {
    var local = 'CREATE TABLE IF NOT EXISTS ' + LOCAL_STORE +
      ' (id UNIQUE, rev, json)';
    tx.executeSql(local, [], function () {
      var sql = 'SELECT ' + DOC_STORE + '.id AS id, ' +
        BY_SEQ_STORE + '.json AS data ' +
        'FROM ' + BY_SEQ_STORE + ' JOIN ' +
        DOC_STORE + ' ON ' + BY_SEQ_STORE + '.seq = ' +
        DOC_STORE + '.winningseq WHERE local = 1';
      tx.executeSql(sql, [], function (tx, res) {
        var rows = [];
        for (var i = 0; i < res.rows.length; i++) {
          rows.push(res.rows.item(i));
        }
        function doNext() {
          if (!rows.length) {
            return callback(tx);
          }
          var row = rows.shift();
          var rev = JSON.parse(row.data)._rev;
          tx.executeSql('INSERT INTO ' + LOCAL_STORE +
              ' (id, rev, json) VALUES (?,?,?)',
              [row.id, rev, row.data], function (tx) {
            tx.executeSql('DELETE FROM ' + DOC_STORE + ' WHERE id=?',
                [row.id], function (tx) {
              tx.executeSql('DELETE FROM ' + BY_SEQ_STORE + ' WHERE seq=?',
                  [row.seq], function () {
                doNext();
              });
            });
          });
        }
        doNext();
      });
    });
  }

  // in this migration, we remove doc_id_rev and just use rev
  function runMigration4(tx, callback) {

    function updateRows(rows) {
      function doNext() {
        if (!rows.length) {
          return callback(tx);
        }
        var row = rows.shift();
        var doc_id_rev = parseHexString(row.hex, encoding);
        var idx = doc_id_rev.lastIndexOf('::');
        var doc_id = doc_id_rev.substring(0, idx);
        var rev = doc_id_rev.substring(idx + 2);
        var sql = 'UPDATE ' + BY_SEQ_STORE +
          ' SET doc_id=?, rev=? WHERE doc_id_rev=?';
        tx.executeSql(sql, [doc_id, rev, doc_id_rev], function () {
          doNext();
        });
      }
      doNext();
    }

    var sql = 'ALTER TABLE ' + BY_SEQ_STORE + ' ADD COLUMN doc_id';
    tx.executeSql(sql, [], function (tx) {
      var sql = 'ALTER TABLE ' + BY_SEQ_STORE + ' ADD COLUMN rev';
      tx.executeSql(sql, [], function (tx) {
        tx.executeSql(BY_SEQ_STORE_DOC_ID_REV_INDEX_SQL, [], function (tx) {
          var sql = 'SELECT hex(doc_id_rev) as hex FROM ' + BY_SEQ_STORE;
          tx.executeSql(sql, [], function (tx, res) {
            var rows = [];
            for (var i = 0; i < res.rows.length; i++) {
              rows.push(res.rows.item(i));
            }
            updateRows(rows);
          });
        });
      });
    });
  }

  // in this migration, we add the attach_and_seq table
  // for issue #2818
  function runMigration5(tx, callback) {

    function migrateAttsAndSeqs(tx) {
      // need to actually populate the table. this is the expensive part,
      // so as an optimization, check first that this database even
      // contains attachments
      var sql = 'SELECT COUNT(*) AS cnt FROM ' + ATTACH_STORE;
      tx.executeSql(sql, [], function (tx, res) {
        var count = res.rows.item(0).cnt;
        if (!count) {
          return callback(tx);
        }

        var offset = 0;
        var pageSize = 10;
        function nextPage() {
          var sql = select(
            SELECT_DOCS + ', ' + DOC_STORE + '.id AS id',
            [DOC_STORE, BY_SEQ_STORE],
            DOC_STORE_AND_BY_SEQ_JOINER,
            null,
            DOC_STORE + '.id '
          );
          sql += ' LIMIT ' + pageSize + ' OFFSET ' + offset;
          offset += pageSize;
          tx.executeSql(sql, [], function (tx, res) {
            if (!res.rows.length) {
              return callback(tx);
            }
            var digestSeqs = {};
            function addDigestSeq(digest, seq) {
              // uniq digest/seq pairs, just in case there are dups
              var seqs = digestSeqs[digest] = (digestSeqs[digest] || []);
              if (seqs.indexOf(seq) === -1) {
                seqs.push(seq);
              }
            }
            for (var i = 0; i < res.rows.length; i++) {
              var row = res.rows.item(i);
              var doc = unstringifyDoc(row.data, row.id, row.rev);
              var atts = Object.keys(doc._attachments || {});
              for (var j = 0; j < atts.length; j++) {
                var att = doc._attachments[atts[j]];
                addDigestSeq(att.digest, row.seq);
              }
            }
            var digestSeqPairs = [];
            Object.keys(digestSeqs).forEach(function (digest) {
              var seqs = digestSeqs[digest];
              seqs.forEach(function (seq) {
                digestSeqPairs.push([digest, seq]);
              });
            });
            if (!digestSeqPairs.length) {
              return nextPage();
            }
            var numDone = 0;
            digestSeqPairs.forEach(function (pair) {
              var sql = 'INSERT INTO ' + ATTACH_AND_SEQ_STORE +
                ' (digest, seq) VALUES (?,?)';
              tx.executeSql(sql, pair, function () {
                if (++numDone === digestSeqPairs.length) {
                  nextPage();
                }
              });
            });
          });
        }
        nextPage();
      });
    }

    var attachAndRev = 'CREATE TABLE IF NOT EXISTS ' +
      ATTACH_AND_SEQ_STORE + ' (digest, seq INTEGER)';
    tx.executeSql(attachAndRev, [], function (tx) {
      tx.executeSql(
        ATTACH_AND_SEQ_STORE_ATTACH_INDEX_SQL, [], function (tx) {
          tx.executeSql(
            ATTACH_AND_SEQ_STORE_SEQ_INDEX_SQL, [],
            migrateAttsAndSeqs);
        });
    });
  }

  // in this migration, we use escapeBlob() and unescapeBlob()
  // instead of reading out the binary as HEX, which is slow
  function runMigration6(tx, callback) {
    var sql = 'ALTER TABLE ' + ATTACH_STORE +
      ' ADD COLUMN escaped TINYINT(1) DEFAULT 0';
    tx.executeSql(sql, [], callback);
  }

  // issue #3136, in this migration we need a "latest seq" as well
  // as the "winning seq" in the doc store
  function runMigration7(tx, callback) {
    var sql = 'ALTER TABLE ' + DOC_STORE +
      ' ADD COLUMN max_seq INTEGER';
    tx.executeSql(sql, [], function (tx) {
      var sql = 'UPDATE ' + DOC_STORE + ' SET max_seq=(SELECT MAX(seq) FROM ' +
        BY_SEQ_STORE + ' WHERE doc_id=id)';
      tx.executeSql(sql, [], function (tx) {
        // add unique index after filling, else we'll get a constraint
        // error when we do the ALTER TABLE
        var sql =
          'CREATE UNIQUE INDEX IF NOT EXISTS \'doc-max-seq-idx\' ON ' +
          DOC_STORE + ' (max_seq)';
        tx.executeSql(sql, [], callback);
      });
    });
  }

  function checkEncoding(tx, cb) {
    // UTF-8 on chrome/android, UTF-16 on safari < 7.1
    tx.executeSql('SELECT HEX("a") AS hex', [], function (tx, res) {
        var hex = res.rows.item(0).hex;
        encoding = hex.length === 2 ? 'UTF-8' : 'UTF-16';
        cb();
      }
    );
  }

  function onGetInstanceId() {
    while (idRequests.length > 0) {
      var idCallback = idRequests.pop();
      idCallback(null, instanceId);
    }
  }

  function onGetVersion(tx, dbVersion) {
    if (dbVersion === 0) {
      // initial schema

      var meta = 'CREATE TABLE IF NOT EXISTS ' + META_STORE +
        ' (dbid, db_version INTEGER)';
      var attach = 'CREATE TABLE IF NOT EXISTS ' + ATTACH_STORE +
        ' (digest UNIQUE, escaped TINYINT(1), body BLOB)';
      var attachAndRev = 'CREATE TABLE IF NOT EXISTS ' +
        ATTACH_AND_SEQ_STORE + ' (digest, seq INTEGER)';
      // TODO: migrate winningseq to INTEGER
      var doc = 'CREATE TABLE IF NOT EXISTS ' + DOC_STORE +
        ' (id unique, json, winningseq, max_seq INTEGER UNIQUE)';
      var seq = 'CREATE TABLE IF NOT EXISTS ' + BY_SEQ_STORE +
        ' (seq INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, ' +
        'json, deleted TINYINT(1), doc_id, rev)';
      var local = 'CREATE TABLE IF NOT EXISTS ' + LOCAL_STORE +
        ' (id UNIQUE, rev, json)';

      // creates
      tx.executeSql(attach);
      tx.executeSql(local);
      tx.executeSql(attachAndRev, [], function () {
        tx.executeSql(ATTACH_AND_SEQ_STORE_SEQ_INDEX_SQL);
        tx.executeSql(ATTACH_AND_SEQ_STORE_ATTACH_INDEX_SQL);
      });
      tx.executeSql(doc, [], function () {
        tx.executeSql(DOC_STORE_WINNINGSEQ_INDEX_SQL);
        tx.executeSql(seq, [], function () {
          tx.executeSql(BY_SEQ_STORE_DELETED_INDEX_SQL);
          tx.executeSql(BY_SEQ_STORE_DOC_ID_REV_INDEX_SQL);
          tx.executeSql(meta, [], function () {
            // mark the db version, and new dbid
            var initSeq = 'INSERT INTO ' + META_STORE +
              ' (db_version, dbid) VALUES (?,?)';
            instanceId = utils.uuid();
            var initSeqArgs = [ADAPTER_VERSION, instanceId];
            tx.executeSql(initSeq, initSeqArgs, function () {
              onGetInstanceId();
            });
          });
        });
      });
    } else { // version > 0

      var setupDone = function () {
        var migrated = dbVersion < ADAPTER_VERSION;
        if (migrated) {
          // update the db version within this transaction
          tx.executeSql('UPDATE ' + META_STORE + ' SET db_version = ' +
            ADAPTER_VERSION);
        }
        // notify db.id() callers
        var sql = 'SELECT dbid FROM ' + META_STORE;
        tx.executeSql(sql, [], function (tx, result) {
          instanceId = result.rows.item(0).dbid;
          onGetInstanceId();
        });
      };

      // would love to use promises here, but then websql
      // ends the transaction early
      var tasks = [
        runMigration2,
        runMigration3,
        runMigration4,
        runMigration5,
        runMigration6,
        runMigration7,
        setupDone
      ];

      // run each migration sequentially
      var i = dbVersion;
      var nextMigration = function (tx) {
        tasks[i - 1](tx, nextMigration);
        i++;
      };
      nextMigration(tx);
    }
  }

  function setup() {
    db.transaction(function (tx) {
      // first check the encoding
      checkEncoding(tx, function () {
        // then get the version
        fetchVersion(tx);
      });
    }, unknownError(callback), dbCreated);
  }

  function fetchVersion(tx) {
    var sql = 'SELECT sql FROM sqlite_master WHERE tbl_name = ' + META_STORE;
    tx.executeSql(sql, [], function (tx, result) {
      if (!result.rows.length) {
        // database hasn't even been created yet (version 0)
        onGetVersion(tx, 0);
      } else if (!/db_version/.test(result.rows.item(0).sql)) {
        // table was created, but without the new db_version column,
        // so add it.
        tx.executeSql('ALTER TABLE ' + META_STORE +
          ' ADD COLUMN db_version INTEGER', [], function () {
          // before version 2, this column didn't even exist
          onGetVersion(tx, 1);
        });
      } else { // column exists, we can safely get it
        tx.executeSql('SELECT db_version FROM ' + META_STORE,
          [], function (tx, result) {
          var dbVersion = result.rows.item(0).db_version;
          onGetVersion(tx, dbVersion);
        });
      }
    });
  }

  if (utils.isCordova()) {
    //to wait until custom api is made in pouch.adapters before doing setup
    window.addEventListener(api._name + '_pouch', function cordova_init() {
      window.removeEventListener(api._name + '_pouch', cordova_init, false);
      setup();
    }, false);
  } else {
    setup();
  }

  api.type = function () {
    return 'websql';
  };

  api._id = utils.toPromise(function (callback) {
    callback(null, instanceId);
  });

  api._info = function (callback) {
    db.readTransaction(function (tx) {
      countDocs(tx, function (docCount) {
        var sql = 'SELECT MAX(seq) AS seq FROM ' + BY_SEQ_STORE;
        tx.executeSql(sql, [], function (tx, res) {
          var updateSeq = res.rows.item(0).seq || 0;
          callback(null, {
            doc_count: docCount,
            update_seq: updateSeq
          });
        });
      });
    }, unknownError(callback));
  };

  api._bulkDocs = function (req, opts, callback) {
    websqlBulkDocs(req, opts, api, db, WebSqlPouch.Changes, callback);
  };

  api._get = function (id, opts, callback) {
    opts = utils.clone(opts);
    var doc;
    var metadata;
    var err;
    if (!opts.ctx) {
      db.readTransaction(function (txn) {
        opts.ctx = txn;
        api._get(id, opts, callback);
      });
      return;
    }
    var tx = opts.ctx;

    function finish() {
      callback(err, {doc: doc, metadata: metadata, ctx: tx});
    }

    var sql;
    var sqlArgs;
    if (opts.rev) {
      sql = select(
        SELECT_DOCS,
        [DOC_STORE, BY_SEQ_STORE],
        DOC_STORE + '.id=' + BY_SEQ_STORE + '.doc_id',
        [BY_SEQ_STORE + '.doc_id=?', BY_SEQ_STORE + '.rev=?']);
      sqlArgs = [id, opts.rev];
    } else {
      sql = select(
        SELECT_DOCS,
        [DOC_STORE, BY_SEQ_STORE],
        DOC_STORE_AND_BY_SEQ_JOINER,
        DOC_STORE + '.id=?');
      sqlArgs = [id];
    }
    tx.executeSql(sql, sqlArgs, function (a, results) {
      if (!results.rows.length) {
        err = errors.error(errors.MISSING_DOC, 'missing');
        return finish();
      }
      var item = results.rows.item(0);
      metadata = utils.safeJsonParse(item.metadata);
      if (item.deleted && !opts.rev) {
        err = errors.error(errors.MISSING_DOC, 'deleted');
        return finish();
      }
      doc = unstringifyDoc(item.data, metadata.id, item.rev);
      finish();
    });
  };

  function countDocs(tx, callback) {

    if (api._docCount !== -1) {
      return callback(api._docCount);
    }

    // count the total rows
    var sql = select(
      'COUNT(' + DOC_STORE + '.id) AS \'num\'',
      [DOC_STORE, BY_SEQ_STORE],
      DOC_STORE_AND_BY_SEQ_JOINER,
      BY_SEQ_STORE + '.deleted=0');

    tx.executeSql(sql, [], function (tx, result) {
      api._docCount = result.rows.item(0).num;
      callback(api._docCount);
    });
  }

  api._allDocs = function (opts, callback) {
    var results = [];
    var totalRows;

    var start = 'startkey' in opts ? opts.startkey : false;
    var end = 'endkey' in opts ? opts.endkey : false;
    var key = 'key' in opts ? opts.key : false;
    var descending = 'descending' in opts ? opts.descending : false;
    var limit = 'limit' in opts ? opts.limit : -1;
    var offset = 'skip' in opts ? opts.skip : 0;
    var inclusiveEnd = opts.inclusive_end !== false;

    var sqlArgs = [];
    var criteria = [];

    if (key !== false) {
      criteria.push(DOC_STORE + '.id = ?');
      sqlArgs.push(key);
    } else if (start !== false || end !== false) {
      if (start !== false) {
        criteria.push(DOC_STORE + '.id ' + (descending ? '<=' : '>=') + ' ?');
        sqlArgs.push(start);
      }
      if (end !== false) {
        var comparator = descending ? '>' : '<';
        if (inclusiveEnd) {
          comparator += '=';
        }
        criteria.push(DOC_STORE + '.id ' + comparator + ' ?');
        sqlArgs.push(end);
      }
      if (key !== false) {
        criteria.push(DOC_STORE + '.id = ?');
        sqlArgs.push(key);
      }
    }

    if (opts.deleted !== 'ok') {
      // report deleted if keys are specified
      criteria.push(BY_SEQ_STORE + '.deleted = 0');
    }

    db.readTransaction(function (tx) {

      // first count up the total rows
      countDocs(tx, function (count) {
        totalRows = count;

        if (limit === 0) {
          return;
        }

        // then actually fetch the documents
        var sql = select(
          SELECT_DOCS,
          [DOC_STORE, BY_SEQ_STORE],
          DOC_STORE_AND_BY_SEQ_JOINER,
          criteria,
          DOC_STORE + '.id ' + (descending ? 'DESC' : 'ASC')
          );
        sql += ' LIMIT ' + limit + ' OFFSET ' + offset;

        tx.executeSql(sql, sqlArgs, function (tx, result) {
          for (var i = 0, l = result.rows.length; i < l; i++) {
            var item = result.rows.item(i);
            var metadata = utils.safeJsonParse(item.metadata);
            var id = metadata.id;
            var data = unstringifyDoc(item.data, id, item.rev);
            var winningRev = data._rev;
            var doc = {
              id: id,
              key: id,
              value: {rev: winningRev}
            };
            if (opts.include_docs) {
              doc.doc = data;
              doc.doc._rev = winningRev;
              if (opts.conflicts) {
                doc.doc._conflicts = merge.collectConflicts(metadata);
              }
              fetchAttachmentsIfNecessary(doc.doc, opts, api, tx);
            }
            if (item.deleted) {
              if (opts.deleted === 'ok') {
                doc.value.deleted = true;
                doc.doc = null;
              } else {
                continue;
              }
            }
            results.push(doc);
          }
        });
      });
    }, unknownError(callback), function () {
      callback(null, {
        total_rows: totalRows,
        offset: opts.skip,
        rows: results
      });
    });
  };

  api._changes = function (opts) {
    opts = utils.clone(opts);

    if (opts.continuous) {
      var id = api._name + ':' + utils.uuid();
      WebSqlPouch.Changes.addListener(api._name, id, api, opts);
      WebSqlPouch.Changes.notify(api._name);
      return {
        cancel: function () {
          WebSqlPouch.Changes.removeListener(api._name, id);
        }
      };
    }

    var descending = opts.descending;

    // Ignore the `since` parameter when `descending` is true
    opts.since = opts.since && !descending ? opts.since : 0;

    var limit = 'limit' in opts ? opts.limit : -1;
    if (limit === 0) {
      limit = 1; // per CouchDB _changes spec
    }

    var returnDocs;
    if ('returnDocs' in opts) {
      returnDocs = opts.returnDocs;
    } else {
      returnDocs = true;
    }
    var results = [];
    var numResults = 0;

    function fetchChanges() {

      var selectStmt =
        DOC_STORE + '.json AS metadata, ' +
        DOC_STORE + '.max_seq AS maxSeq, ' +
        BY_SEQ_STORE + '.json AS winningDoc, ' +
        BY_SEQ_STORE + '.rev AS winningRev ';

      var from = DOC_STORE + ' JOIN ' + BY_SEQ_STORE;

      var joiner = DOC_STORE + '.id=' + BY_SEQ_STORE + '.doc_id' +
        ' AND ' + DOC_STORE + '.winningseq=' + BY_SEQ_STORE + '.seq';

      var criteria = ['maxSeq > ?'];
      var sqlArgs = [opts.since];

      if (opts.doc_ids) {
        criteria.push(DOC_STORE + '.id IN ' + qMarks(opts.doc_ids.length));
        sqlArgs = sqlArgs.concat(opts.doc_ids);
      }

      var orderBy = 'maxSeq ' + (descending ? 'DESC' : 'ASC');

      var sql = select(selectStmt, from, joiner, criteria, orderBy);

      var filter = utils.filterChange(opts);
      if (!opts.view && !opts.filter) {
        // we can just limit in the query
        sql += ' LIMIT ' + limit;
      }

      var lastSeq = opts.since || 0;
      db.readTransaction(function (tx) {
        tx.executeSql(sql, sqlArgs, function (tx, result) {
          function reportChange(change) {
            return function () {
              opts.onChange(change);
            };
          }
          for (var i = 0, l = result.rows.length; i < l; i++) {
            var item = result.rows.item(i);
            var metadata = utils.safeJsonParse(item.metadata);
            lastSeq = item.maxSeq;

            var doc = unstringifyDoc(item.winningDoc, metadata.id,
              item.winningRev);
            var change = opts.processChange(doc, metadata, opts);
            change.seq = item.maxSeq;
            if (filter(change)) {
              numResults++;
              if (returnDocs) {
                results.push(change);
              }
              // process the attachment immediately
              // for the benefit of live listeners
              if (opts.attachments && opts.include_docs) {
                fetchAttachmentsIfNecessary(doc, opts, api, tx,
                  reportChange(change));
              } else {
                reportChange(change)();
              }
            }
            if (numResults === limit) {
              break;
            }
          }
        });
      }, unknownError(opts.complete), function () {
        if (!opts.continuous) {
          opts.complete(null, {
            results: results,
            last_seq: lastSeq
          });
        }
      });
    }

    fetchChanges();
  };

  api._close = function (callback) {
    //WebSQL databases do not need to be closed
    callback();
  };

  api._getAttachment = function (attachment, opts, callback) {
    var res;
    var tx = opts.ctx;
    var digest = attachment.digest;
    var type = attachment.content_type;
    var sql = 'SELECT escaped, ' +
      'CASE WHEN escaped = 1 THEN body ELSE HEX(body) END AS body FROM ' +
      ATTACH_STORE + ' WHERE digest=?';
    tx.executeSql(sql, [digest], function (tx, result) {
      // websql has a bug where \u0000 causes early truncation in strings
      // and blobs. to work around this, we used to use the hex() function,
      // but that's not performant. after migration 6, we remove \u0000
      // and add it back in afterwards
      var item = result.rows.item(0);
      var data = item.escaped ? websqlUtils.unescapeBlob(item.body) :
        parseHexString(item.body, encoding);
      if (opts.encode) {
        res = btoa(data);
      } else {
        data = utils.fixBinary(data);
        res = utils.createBlob([data], {type: type});
      }
      callback(null, res);
    });
  };

  api._getRevisionTree = function (docId, callback) {
    db.readTransaction(function (tx) {
      var sql = 'SELECT json AS metadata FROM ' + DOC_STORE + ' WHERE id = ?';
      tx.executeSql(sql, [docId], function (tx, result) {
        if (!result.rows.length) {
          callback(errors.error(errors.MISSING_DOC));
        } else {
          var data = utils.safeJsonParse(result.rows.item(0).metadata);
          callback(null, data.rev_tree);
        }
      });
    });
  };

  api._doCompaction = function (docId, revs, callback) {
    if (!revs.length) {
      return callback();
    }
    db.transaction(function (tx) {

      // update doc store
      var sql = 'SELECT json AS metadata FROM ' + DOC_STORE + ' WHERE id = ?';
      tx.executeSql(sql, [docId], function (tx, result) {
        var metadata = utils.safeJsonParse(result.rows.item(0).metadata);
        merge.traverseRevTree(metadata.rev_tree, function (isLeaf, pos,
                                                           revHash, ctx, opts) {
          var rev = pos + '-' + revHash;
          if (revs.indexOf(rev) !== -1) {
            opts.status = 'missing';
          }
        });

        var sql = 'UPDATE ' + DOC_STORE + ' SET json = ? WHERE id = ?';
        tx.executeSql(sql, [utils.safeJsonStringify(metadata), docId]);
      });

      compactRevs(revs, docId, tx);
    }, unknownError(callback), function () {
      callback();
    });
  };

  api._getLocal = function (id, callback) {
    db.readTransaction(function (tx) {
      var sql = 'SELECT json, rev FROM ' + LOCAL_STORE + ' WHERE id=?';
      tx.executeSql(sql, [id], function (tx, res) {
        if (res.rows.length) {
          var item = res.rows.item(0);
          var doc = unstringifyDoc(item.json, id, item.rev);
          callback(null, doc);
        } else {
          callback(errors.error(errors.MISSING_DOC));
        }
      });
    });
  };

  api._putLocal = function (doc, opts, callback) {
    if (typeof opts === 'function') {
      callback = opts;
      opts = {};
    }
    delete doc._revisions; // ignore this, trust the rev
    var oldRev = doc._rev;
    var id = doc._id;
    var newRev;
    if (!oldRev) {
      newRev = doc._rev = '0-1';
    } else {
      newRev = doc._rev = '0-' + (parseInt(oldRev.split('-')[1], 10) + 1);
    }
    var json = stringifyDoc(doc);

    var ret;
    function putLocal(tx) {
      var sql;
      var values;
      if (oldRev) {
        sql = 'UPDATE ' + LOCAL_STORE + ' SET rev=?, json=? ' +
          'WHERE id=? AND rev=?';
        values = [newRev, json, id, oldRev];
      } else {
        sql = 'INSERT INTO ' + LOCAL_STORE + ' (id, rev, json) VALUES (?,?,?)';
        values = [id, newRev, json];
      }
      tx.executeSql(sql, values, function (tx, res) {
        if (res.rowsAffected) {
          ret = {ok: true, id: id, rev: newRev};
          if (opts.ctx) { // return immediately
            callback(null, ret);
          }
        } else {
          callback(errors.error(errors.REV_CONFLICT));
        }
      }, function () {
        callback(errors.error(errors.REV_CONFLICT));
        return false; // ack that we handled the error
      });
    }

    if (opts.ctx) {
      putLocal(opts.ctx);
    } else {
      db.transaction(function (tx) {
        putLocal(tx);
      }, unknownError(callback), function () {
        if (ret) {
          callback(null, ret);
        }
      });
    }
  };

  api._removeLocal = function (doc, callback) {
    var ret;
    db.transaction(function (tx) {
      var sql = 'DELETE FROM ' + LOCAL_STORE + ' WHERE id=? AND rev=?';
      var params = [doc._id, doc._rev];
      tx.executeSql(sql, params, function (tx, res) {
        if (!res.rowsAffected) {
          return callback(errors.error(errors.MISSING_DOC));
        }
        ret = {ok: true, id: doc._id, rev: '0-0'};
      });
    }, unknownError(callback), function () {
      if (ret) {
        callback(null, ret);
      }
    });
  };
}

WebSqlPouch.valid = function () {
  return !!openDBFunction;
};

WebSqlPouch.destroy = utils.toPromise(function (name, opts, callback) {
  WebSqlPouch.Changes.removeAllListeners(name);
  var size = getSize(opts);
  var db = openDB(name, POUCH_VERSION, name, size);
  db.transaction(function (tx) {
    var stores = [DOC_STORE, BY_SEQ_STORE, ATTACH_STORE, META_STORE,
      LOCAL_STORE, ATTACH_AND_SEQ_STORE];
    stores.forEach(function (store) {
      tx.executeSql('DROP TABLE IF EXISTS ' + store, []);
    });
  }, unknownError(callback), function () {
    if (utils.hasLocalStorage()) {
      delete window.localStorage['_pouch__websqldb_' + name];
      delete window.localStorage[name];
    }
    callback(null, {'ok': true});
  });
});

WebSqlPouch.Changes = new utils.Changes();

module.exports = WebSqlPouch;

},{}],13:[function(_dereq_,module,exports){
'use strict';
var utils = _dereq_(32);
var merge = _dereq_(27);
var errors = _dereq_(19);
var EE = _dereq_(36).EventEmitter;
var evalFilter = _dereq_(25);
var evalView = _dereq_(26);
module.exports = Changes;
utils.inherits(Changes, EE);

function Changes(db, opts, callback) {
  EE.call(this);
  var self = this;
  this.db = db;
  opts = opts ? utils.clone(opts) : {};
  var oldComplete = callback || opts.complete || function () {};
  var complete = opts.complete = utils.once(function (err, resp) {
    if (err) {
      self.emit('error', err);
    } else {
      self.emit('complete', resp);
    }
    self.removeAllListeners();
    db.removeListener('destroyed', onDestroy);
  });
  if (oldComplete) {
    self.on('complete', function (resp) {
      oldComplete(null, resp);
    });
    self.on('error', function (err) {
      oldComplete(err);
    });
  }
  var oldOnChange = opts.onChange;
  if (oldOnChange) {
    self.on('change', oldOnChange);
  }
  function onDestroy() {
    self.cancel();
  }
  db.once('destroyed', onDestroy);

  opts.onChange = function (change) {
    if (opts.isCancelled) {
      return;
    }
    self.emit('change', change);
    if (self.startSeq && self.startSeq <= change.seq) {
      self.emit('uptodate');
      self.startSeq = false;
    }
    if (change.deleted) {
      self.emit('delete', change);
    } else if (change.changes.length === 1 &&
      change.changes[0].rev.slice(0, 2) === '1-') {
      self.emit('create', change);
    } else {
      self.emit('update', change);
    }
  };

  var promise = new utils.Promise(function (fulfill, reject) {
    opts.complete = function (err, res) {
      if (err) {
        reject(err);
      } else {
        fulfill(res);
      }
    };
  });
  self.once('cancel', function () {
    if (oldOnChange) {
      self.removeListener('change', oldOnChange);
    }
    opts.complete(null, {status: 'cancelled'});
  });
  this.then = promise.then.bind(promise);
  this['catch'] = promise['catch'].bind(promise);
  this.then(function (result) {
    complete(null, result);
  }, complete);



  if (!db.taskqueue.isReady) {
    db.taskqueue.addTask(function () {
      if (self.isCancelled) {
        self.emit('cancel');
      } else {
        self.doChanges(opts);
      }
    });
  } else {
    self.doChanges(opts);
  }
}
Changes.prototype.cancel = function () {
  this.isCancelled = true;
  if (this.db.taskqueue.isReady) {
    this.emit('cancel');
  }
};
function processChange(doc, metadata, opts) {
  var changeList = [{rev: doc._rev}];
  if (opts.style === 'all_docs') {
    changeList = merge.collectLeaves(metadata.rev_tree)
    .map(function (x) { return {rev: x.rev}; });
  }
  var change = {
    id: metadata.id,
    changes: changeList,
    doc: doc
  };

  if (utils.isDeleted(metadata, doc._rev)) {
    change.deleted = true;
  }
  if (opts.conflicts) {
    change.doc._conflicts = merge.collectConflicts(metadata);
    if (!change.doc._conflicts.length) {
      delete change.doc._conflicts;
    }
  }
  return change;
}

Changes.prototype.doChanges = function (opts) {
  var self = this;
  var callback = opts.complete;

  opts = utils.clone(opts);
  if ('live' in opts && !('continuous' in opts)) {
    opts.continuous = opts.live;
  }
  opts.processChange = processChange;

  if (opts.since === 'latest') {
    opts.since = 'now';
  }
  if (!opts.since) {
    opts.since = 0;
  }
  if (opts.since === 'now') {
    this.db.info().then(function (info) {
      if (self.isCancelled) {
        callback(null, {status: 'cancelled'});
        return;
      }
      opts.since = info.update_seq;
      self.doChanges(opts);
    }, callback);
    return;
  }

  if (opts.continuous && opts.since !== 'now') {
    this.db.info().then(function (info) {
      self.startSeq = info.update_seq;
    }, function (err) {
      if (err.id === 'idbNull') {
        //db closed before this returned
        //thats ok
        return;
      }
      throw err;
    });
  }

  if (this.db.type() !== 'http' &&
      opts.filter && typeof opts.filter === 'string' &&
      !opts.doc_ids) {
    return this.filterChanges(opts);
  }

  if (!('descending' in opts)) {
    opts.descending = false;
  }

  // 0 and 1 should return 1 document
  opts.limit = opts.limit === 0 ? 1 : opts.limit;
  opts.complete = callback;
  var newPromise = this.db._changes(opts);
  if (newPromise && typeof newPromise.cancel === 'function') {
    var cancel = self.cancel;
    self.cancel = utils.getArguments(function (args) {
      newPromise.cancel();
      cancel.apply(this, args);
    });
  }
};

Changes.prototype.filterChanges = function (opts) {
  var self = this;
  var callback = opts.complete;
  if (opts.filter === '_view') {
    if (!opts.view || typeof opts.view !== 'string') {
      var err = errors.error(errors.BAD_REQUEST,
                             '`view` filter parameter is not provided.');
      callback(err);
      return;
    }
    // fetch a view from a design doc, make it behave like a filter
    var viewName = opts.view.split('/');
    this.db.get('_design/' + viewName[0], function (err, ddoc) {
      if (self.isCancelled) {
        callback(null, {status: 'cancelled'});
        return;
      }
      if (err) {
        callback(errors.generateErrorFromResponse(err));
        return;
      }
      if (ddoc && ddoc.views && ddoc.views[viewName[1]]) {
        
        var filter = evalView(ddoc.views[viewName[1]].map);
        opts.filter = filter;
        self.doChanges(opts);
        return;
      }
      var msg = ddoc.views ? 'missing json key: ' + viewName[1] :
        'missing json key: views';
      if (!err) {
        err = errors.error(errors.MISSING_DOC, msg);
      }
      callback(err);
      return;
    });
  } else {
    // fetch a filter from a design doc
    var filterName = opts.filter.split('/');
    this.db.get('_design/' + filterName[0], function (err, ddoc) {
      if (self.isCancelled) {
        callback(null, {status: 'cancelled'});
        return;
      }
      if (err) {
        callback(errors.generateErrorFromResponse(err));
        return;
      }
      if (ddoc && ddoc.filters && ddoc.filters[filterName[1]]) {
        var filter = evalFilter(ddoc.filters[filterName[1]]);
        opts.filter = filter;
        self.doChanges(opts);
        return;
      } else {
        var msg = (ddoc && ddoc.filters) ? 'missing json key: ' + filterName[1]
          : 'missing json key: filters';
        if (!err) {
          err = errors.error(errors.MISSING_DOC, msg);
        }
        callback(err);
        return;
      }
    });
  }
};
},{}],14:[function(_dereq_,module,exports){
'use strict';

var utils = _dereq_(32);
var pouchCollate = _dereq_(60);
var collate = pouchCollate.collate;

function updateCheckpoint(db, id, checkpoint, returnValue) {
  return db.get(id)["catch"](function (err) {
    if (err.status === 404) {
      if (db.type() === 'http') {
        utils.explain404(
          'PouchDB is just checking if a remote checkpoint exists.');
      }
      return {_id: id};
    }
    throw err;
  }).then(function (doc) {
    if (returnValue.cancelled) {
      return;
    }
    doc.last_seq = checkpoint;
    return db.put(doc);
  });
}

function Checkpointer(src, target, id, returnValue) {
  this.src = src;
  this.target = target;
  this.id = id;
  this.returnValue = returnValue;
}

Checkpointer.prototype.writeCheckpoint = function (checkpoint) {
  var self = this;
  return this.updateTarget(checkpoint).then(function () {
    return self.updateSource(checkpoint);
  });
};

Checkpointer.prototype.updateTarget = function (checkpoint) {
  return updateCheckpoint(this.target, this.id, checkpoint, this.returnValue);
};

Checkpointer.prototype.updateSource = function (checkpoint) {
  var self = this;
  if (this.readOnlySource) {
    return utils.Promise.resolve(true);
  }
  return updateCheckpoint(this.src, this.id, checkpoint, this.returnValue)[
    "catch"](function (err) {
      var isForbidden = typeof err.status === 'number' &&
        Math.floor(err.status / 100) === 4;
      if (isForbidden) {
        self.readOnlySource = true;
        return true;
      }
      throw err;
    });
};

Checkpointer.prototype.getCheckpoint = function () {
  var self = this;
  return self.target.get(self.id).then(function (targetDoc) {
    return self.src.get(self.id).then(function (sourceDoc) {
      if (collate(targetDoc.last_seq, sourceDoc.last_seq) === 0) {
        return sourceDoc.last_seq;
      }
      return 0;
    }, function (err) {
      if (err.status === 404 && targetDoc.last_seq) {
        return self.src.put({
          _id: self.id,
          last_seq: 0
        }).then(function () {
          return 0;
        }, function (err) {
          if (err.status === 401) {
            self.readOnlySource = true;
            return targetDoc.last_seq;
          }
          return 0;
        });
      }
      throw err;
    });
  })["catch"](function (err) {
    if (err.status !== 404) {
      throw err;
    }
    return 0;
  });
};

module.exports = Checkpointer;

},{}],15:[function(_dereq_,module,exports){
(function (process,global){
/*globals cordova */
"use strict";

var Adapter = _dereq_(1);
var utils = _dereq_(32);
var TaskQueue = _dereq_(31);
var Promise = utils.Promise;

function defaultCallback(err) {
  if (err && global.debug) {
    console.error(err);
  }
}

utils.inherits(PouchDB, Adapter);
function PouchDB(name, opts, callback) {

  if (!(this instanceof PouchDB)) {
    return new PouchDB(name, opts, callback);
  }
  var self = this;
  if (typeof opts === 'function' || typeof opts === 'undefined') {
    callback = opts;
    opts = {};
  }

  if (name && typeof name === 'object') {
    opts = name;
    name = undefined;
  }
  if (typeof callback === 'undefined') {
    callback = defaultCallback;
  }
  opts = opts || {};
  this.__opts = opts;
  var oldCB = callback;
  self.auto_compaction = opts.auto_compaction;
  self.prefix = PouchDB.prefix;
  Adapter.call(self);
  self.taskqueue = new TaskQueue();
  var promise = new Promise(function (fulfill, reject) {
    callback = function (err, resp) {
      if (err) {
        return reject(err);
      }
      delete resp.then;
      fulfill(resp);
    };
  
    opts = utils.clone(opts);
    var originalName = opts.name || name;
    var backend, error;
    (function () {
      try {

        if (typeof originalName !== 'string') {
          error = new Error('Missing/invalid DB name');
          error.code = 400;
          throw error;
        }

        backend = PouchDB.parseAdapter(originalName, opts);
        
        opts.originalName = originalName;
        opts.name = backend.name;
        if (opts.prefix && backend.adapter !== 'http' &&
            backend.adapter !== 'https') {
          opts.name = opts.prefix + opts.name;
        }
        opts.adapter = opts.adapter || backend.adapter;
        self._adapter = opts.adapter;
        self._db_name = originalName;
        if (!PouchDB.adapters[opts.adapter]) {
          error = new Error('Adapter is missing');
          error.code = 404;
          throw error;
        }

        if (!PouchDB.adapters[opts.adapter].valid()) {
          error = new Error('Invalid Adapter');
          error.code = 404;
          throw error;
        }
      } catch (err) {
        self.taskqueue.fail(err);
        self.changes = utils.toPromise(function (opts) {
          if (opts.complete) {
            opts.complete(err);
          }
        });
      }
    }());
    if (error) {
      return reject(error); // constructor error, see above
    }
    self.adapter = opts.adapter;

    // needs access to PouchDB;
    self.replicate = {};

    self.replicate.from = function (url, opts, callback) {
      return self.constructor.replicate(url, self, opts, callback);
    };

    self.replicate.to = function (url, opts, callback) {
      return self.constructor.replicate(self, url, opts, callback);
    };

    self.sync = function (dbName, opts, callback) {
      return self.constructor.sync(self, dbName, opts, callback);
    };

    self.replicate.sync = self.sync;

    self.destroy = utils.adapterFun('destroy', function (callback) {
      var self = this;
      var opts = this.__opts || {};
      self.info(function (err, info) {
        if (err) {
          return callback(err);
        }
        opts.internal = true;
        self.constructor.destroy(info.db_name, opts, callback);
      });
    });

    PouchDB.adapters[opts.adapter].call(self, opts, function (err) {
      if (err) {
        if (callback) {
          self.taskqueue.fail(err);
          callback(err);
        }
        return;
      }
      function destructionListener(event) {
        if (event === 'destroyed') {
          self.emit('destroyed');
          PouchDB.removeListener(originalName, destructionListener);
        }
      }
      PouchDB.on(originalName, destructionListener);
      self.emit('created', self);
      PouchDB.emit('created', opts.originalName);
      self.taskqueue.ready(self);
      callback(null, self);
    });

    if (opts.skipSetup) {
      self.taskqueue.ready(self);
      process.nextTick(function () {
        callback(null, self);
      });
    }

    if (utils.isCordova()) {
      //to inform websql adapter that we can use api
      cordova.fireWindowEvent(opts.name + "_pouch", {});
    }
  });
  promise.then(function (resp) {
    oldCB(null, resp);
  }, oldCB);
  self.then = promise.then.bind(promise);
  self["catch"] = promise["catch"].bind(promise);
}

PouchDB.debug = _dereq_(38);

module.exports = PouchDB;

}).call(this,_dereq_(37),typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{}],16:[function(_dereq_,module,exports){
"use strict";

var createBlob = _dereq_(17);
var errors = _dereq_(19);
var utils = _dereq_(32);
var hasUpload;

function ajax(options, adapterCallback) {

  var requestCompleted = false;
  var callback = utils.getArguments(function (args) {
    if (requestCompleted) {
      return;
    }
    adapterCallback.apply(this, args);
    requestCompleted = true;
  });

  if (typeof options === "function") {
    callback = options;
    options = {};
  }

  options = utils.clone(options);

  var defaultOptions = {
    method : "GET",
    headers: {},
    json: true,
    processData: true,
    timeout: 10000,
    cache: false
  };

  options = utils.extend(true, defaultOptions, options);

  // cache-buster, specifically designed to work around IE's aggressive caching
  // see http://www.dashbay.com/2011/05/internet-explorer-caches-ajax/
  if (options.method === 'GET' && !options.cache) {
    var hasArgs = options.url.indexOf('?') !== -1;
    options.url += (hasArgs ? '&' : '?') + '_nonce=' + utils.uuid(16);
  }

  function onSuccess(obj, resp, cb) {
    if (!options.binary && !options.json && options.processData &&
      typeof obj !== 'string') {
      obj = JSON.stringify(obj);
    } else if (!options.binary && options.json && typeof obj === 'string') {
      try {
        obj = JSON.parse(obj);
      } catch (e) {
        // Probably a malformed JSON from server
        return cb(e);
      }
    }
    if (Array.isArray(obj)) {
      obj = obj.map(function (v) {
        if (v.error || v.missing) {
          return errors.generateErrorFromResponse(v);
        } else {
          return v;
        }
      });
    }
    cb(null, obj, resp);
  }

  function onError(err, cb) {
    var errParsed, errObj;
    try {
      errParsed = JSON.parse(err.responseText);
      //would prefer not to have a try/catch clause
      errObj = errors.generateErrorFromResponse(errParsed);
    } catch (e) {
      errObj = errors.generateErrorFromResponse(err);
    }
    if (err.withCredentials && err.status === 0) {
      // apparently this is what we get when the method
      // is reported as not allowed by CORS. so fudge it
      errObj.status = 405;
      errObj.statusText = "Method Not Allowed";
    }
    cb(errObj);
  }

  var timer;
  var xhr;
  if (options.xhr) {
    xhr = new options.xhr();
  } else {
    xhr = new XMLHttpRequest();
  }
  xhr.open(options.method, options.url);
  xhr.withCredentials = true;

  if (options.json) {
    options.headers.Accept = 'application/json';
    options.headers['Content-Type'] = options.headers['Content-Type'] ||
      'application/json';
    if (options.body &&
        options.processData &&
        typeof options.body !== "string") {
      options.body = JSON.stringify(options.body);
    }
  }

  if (options.binary) {
    xhr.responseType = 'arraybuffer';
  }

  var createCookie = function (name, value, days) {
    var expires = "";
    if (days) {
      var date = new Date();
      date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
      expires = "; expires=" + date.toGMTString();
    }
    document.cookie = name + "=" + value + expires + "; path=/";
  };

  for (var key in options.headers) {
    if (options.headers.hasOwnProperty(key)) {
      if (key === 'Cookie') {
        var cookie = options.headers[key].split('=');
        createCookie(cookie[0], cookie[1], 10);
      } else {
        xhr.setRequestHeader(key, options.headers[key]);
      }
    }
  }

  if (!("body" in options)) {
    options.body = null;
  }

  var abortReq = function () {
    if (requestCompleted) {
      return;
    }
    xhr.abort();
    onError(xhr, callback);
  };

  xhr.onreadystatechange = function () {
    if (xhr.readyState !== 4 || requestCompleted) {
      return;
    }
    clearTimeout(timer);
    if (xhr.status >= 200 && xhr.status < 300) {
      var data;
      if (options.binary) {
        data = createBlob([xhr.response || ''], {
          type: xhr.getResponseHeader('Content-Type')
        });
      } else {
        data = xhr.responseText;
      }
      onSuccess(data, xhr, callback);
    } else {
      onError(xhr, callback);
    }
  };

  if (options.timeout > 0) {
    timer = setTimeout(abortReq, options.timeout);
    xhr.onprogress = function () {
      clearTimeout(timer);
      timer = setTimeout(abortReq, options.timeout);
    };
    if (typeof hasUpload === 'undefined') {
      // IE throws an error if you try to access it directly
      hasUpload = Object.keys(xhr).indexOf('upload') !== -1;
    }
    if (hasUpload) { // does not exist in ie9
      xhr.upload.onprogress = xhr.onprogress;
    }
  }
  if (options.body && (options.body instanceof Blob)) {
    utils.readAsBinaryString(options.body, function (binary) {
      xhr.send(utils.fixBinary(binary));
    });
  } else {
    xhr.send(options.body);
  }
  return {abort: abortReq};
}

module.exports = ajax;

},{}],17:[function(_dereq_,module,exports){
(function (global){
"use strict";

//Abstracts constructing a Blob object, so it also works in older
//browsers that don't support the native Blob constructor. (i.e.
//old QtWebKit versions, at least).
function createBlob(parts, properties) {
  parts = parts || [];
  properties = properties || {};
  try {
    return new Blob(parts, properties);
  } catch (e) {
    if (e.name !== "TypeError") {
      throw e;
    }
    var BlobBuilder = global.BlobBuilder ||
                      global.MSBlobBuilder ||
                      global.MozBlobBuilder ||
                      global.WebKitBlobBuilder;
    var builder = new BlobBuilder();
    for (var i = 0; i < parts.length; i += 1) {
      builder.append(parts[i]);
    }
    return builder.getBlob(properties.type);
  }
}

module.exports = createBlob;


}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{}],18:[function(_dereq_,module,exports){
// hey guess what, we don't need this in the browser
module.exports = {};
},{}],19:[function(_dereq_,module,exports){
"use strict";

var inherits = _dereq_(41);
inherits(PouchError, Error);

function PouchError(opts) {
  Error.call(opts.reason);
  this.status = opts.status;
  this.name = opts.error;
  this.message = opts.reason;
  this.error = true;
}

PouchError.prototype.toString = function () {
  return JSON.stringify({
    status: this.status,
    name: this.name,
    message: this.message
  });
};

exports.UNAUTHORIZED = new PouchError({
  status: 401,
  error: 'unauthorized',
  reason: "Name or password is incorrect."
});

exports.MISSING_BULK_DOCS = new PouchError({
  status: 400,
  error: 'bad_request',
  reason: "Missing JSON list of 'docs'"
});

exports.MISSING_DOC = new PouchError({
  status: 404,
  error: 'not_found',
  reason: 'missing'
});

exports.REV_CONFLICT = new PouchError({
  status: 409,
  error: 'conflict',
  reason: 'Document update conflict'
});

exports.INVALID_ID = new PouchError({
  status: 400,
  error: 'invalid_id',
  reason: '_id field must contain a string'
});

exports.MISSING_ID = new PouchError({
  status: 412,
  error: 'missing_id',
  reason: '_id is required for puts'
});

exports.RESERVED_ID = new PouchError({
  status: 400,
  error: 'bad_request',
  reason: 'Only reserved document ids may start with underscore.'
});

exports.NOT_OPEN = new PouchError({
  status: 412,
  error: 'precondition_failed',
  reason: 'Database not open'
});

exports.UNKNOWN_ERROR = new PouchError({
  status: 500,
  error: 'unknown_error',
  reason: 'Database encountered an unknown error'
});

exports.BAD_ARG = new PouchError({
  status: 500,
  error: 'badarg',
  reason: 'Some query argument is invalid'
});

exports.INVALID_REQUEST = new PouchError({
  status: 400,
  error: 'invalid_request',
  reason: 'Request was invalid'
});

exports.QUERY_PARSE_ERROR = new PouchError({
  status: 400,
  error: 'query_parse_error',
  reason: 'Some query parameter is invalid'
});

exports.DOC_VALIDATION = new PouchError({
  status: 500,
  error: 'doc_validation',
  reason: 'Bad special document member'
});

exports.BAD_REQUEST = new PouchError({
  status: 400,
  error: 'bad_request',
  reason: 'Something wrong with the request'
});

exports.NOT_AN_OBJECT = new PouchError({
  status: 400,
  error: 'bad_request',
  reason: 'Document must be a JSON object'
});

exports.DB_MISSING = new PouchError({
  status: 404,
  error: 'not_found',
  reason: 'Database not found'
});

exports.IDB_ERROR = new PouchError({
  status: 500,
  error: 'indexed_db_went_bad',
  reason: 'unknown'
});

exports.WSQ_ERROR = new PouchError({
  status: 500,
  error: 'web_sql_went_bad',
  reason: 'unknown'
});

exports.LDB_ERROR = new PouchError({
  status: 500,
  error: 'levelDB_went_went_bad',
  reason: 'unknown'
});

exports.FORBIDDEN = new PouchError({
  status: 403,
  error: 'forbidden',
  reason: 'Forbidden by design doc validate_doc_update function'
});

exports.INVALID_REV = new PouchError({
  status: 400,
  error: 'bad_request',
  reason: 'Invalid rev format'
});

exports.FILE_EXISTS = new PouchError({
  status: 412,
  error: 'file_exists',
  reason: 'The database could not be created, the file already exists.'
});

exports.MISSING_STUB = new PouchError({
  status: 412,
  error: 'missing_stub'
});

exports.error = function (error, reason, name) {
  function CustomPouchError(reason) {
    // inherit error properties from our parent error manually
    // so as to allow proper JSON parsing.
    /* jshint ignore:start */
    for (var p in error) {
      if (typeof error[p] !== 'function') {
        this[p] = error[p];
      }
    }
    /* jshint ignore:end */
    if (name !== undefined) {
      this.name = name;
    }
    if (reason !== undefined) {
      this.reason = reason;
    }
  }
  CustomPouchError.prototype = PouchError.prototype;
  return new CustomPouchError(reason);
};

// Find one of the errors defined above based on the value
// of the specified property.
// If reason is provided prefer the error matching that reason.
// This is for differentiating between errors with the same name and status,
// eg, bad_request.
exports.getErrorTypeByProp = function (prop, value, reason) {
  var errors = exports;
  var keys = Object.keys(errors).filter(function (key) {
    var error = errors[key];
    return typeof error !== 'function' && error[prop] === value;
  });
  var key = reason && keys.filter(function (key) {
        var error = errors[key];
        return error.message === reason;
      })[0] || keys[0];
  return (key) ? errors[key] : null;
};

exports.generateErrorFromResponse = function (res) {
  var error, errName, errType, errMsg, errReason;
  var errors = exports;

  errName = (res.error === true && typeof res.name === 'string') ?
              res.name :
              res.error;
  errReason = res.reason;
  errType = errors.getErrorTypeByProp('name', errName, errReason);

  if (res.missing ||
      errReason === 'missing' ||
      errReason === 'deleted' ||
      errName === 'not_found') {
    errType = errors.MISSING_DOC;
  } else if (errName === 'doc_validation') {
    // doc validation needs special treatment since
    // res.reason depends on the validation error.
    // see utils.js
    errType = errors.DOC_VALIDATION;
    errMsg = errReason;
  } else if (errName === 'bad_request' && errType.message !== errReason) {
    // if bad_request error already found based on reason don't override.

    // attachment errors.
    if (errReason.indexOf('unknown stub attachment') === 0) {
      errType = errors.MISSING_STUB;
      errMsg = errReason;
    } else {
      errType = errors.BAD_REQUEST;
    }
  }

  // fallback to error by statys or unknown error.
  if (!errType) {
    errType = errors.getErrorTypeByProp('status', res.status, errReason) ||
                errors.UNKNOWN_ERROR;
  }

  error = errors.error(errType, errReason, errName);

  // Keep custom message.
  if (errMsg) {
    error.message = errMsg;
  }

  // Keep helpful response data in our error messages.
  if (res.id) {
    error.id = res.id;
  }
  if (res.status) {
    error.status = res.status;
  }
  if (res.statusText) {
    error.name = res.statusText;
  }
  if (res.missing) {
    error.missing = res.missing;
  }

  return error;
};

},{}],20:[function(_dereq_,module,exports){
(function (process,global){
'use strict';

var crypto = _dereq_(35);
var Md5 = _dereq_(96);
var setImmediateShim = global.setImmediate || global.setTimeout;
var MD5_CHUNK_SIZE = 32768;

function sliceShim(arrayBuffer, begin, end) {
  if (typeof arrayBuffer.slice === 'function') {
    if (!begin) {
      return arrayBuffer.slice();
    } else if (!end) {
      return arrayBuffer.slice(begin);
    } else {
      return arrayBuffer.slice(begin, end);
    }
  }
  //
  // shim for IE courtesy of http://stackoverflow.com/a/21440217
  //

  //If `begin`/`end` is unspecified, Chrome assumes 0, so we do the same
  //Chrome also converts the values to integers via flooring
  begin = Math.floor(begin || 0);
  end = Math.floor(end || 0);

  var len = arrayBuffer.byteLength;

  //If either `begin` or `end` is negative, it refers to an
  //index from the end of the array, as opposed to from the beginning.
  //The range specified by the `begin` and `end` values is clamped to the
  //valid index range for the current array.
  begin = begin < 0 ? Math.max(begin + len, 0) : Math.min(len, begin);
  end = end < 0 ? Math.max(end + len, 0) : Math.min(len, end);

  //If the computed length of the new ArrayBuffer would be negative, it
  //is clamped to zero.
  if (end - begin <= 0) {
    return new ArrayBuffer(0);
  }

  var result = new ArrayBuffer(end - begin);
  var resultBytes = new Uint8Array(result);
  var sourceBytes = new Uint8Array(arrayBuffer, begin, end - begin);

  resultBytes.set(sourceBytes);

  return result;
}

// convert a 64-bit int to a binary string
function intToString(int) {
  var bytes = [
    (int & 0xff),
    ((int >>> 8) & 0xff),
    ((int >>> 16) & 0xff),
    ((int >>> 24) & 0xff)
  ];
  return bytes.map(function (byte) {
    return String.fromCharCode(byte);
  }).join('');
}

// convert an array of 64-bit ints into
// a base64-encoded string
function rawToBase64(raw) {
  var res = '';
  for (var i = 0; i < raw.length; i++) {
    res += intToString(raw[i]);
  }
  return btoa(res);
}

module.exports = function (data, callback) {
  if (!process.browser) {
    var base64 = crypto.createHash('md5').update(data).digest('base64');
    callback(null, base64);
    return;
  }
  var inputIsString = typeof data === 'string';
  var len = inputIsString ? data.length : data.byteLength;
  var chunkSize = Math.min(MD5_CHUNK_SIZE, len);
  var chunks = Math.ceil(len / chunkSize);
  var currentChunk = 0;
  var buffer = inputIsString ? new Md5() : new Md5.ArrayBuffer();

  function append(buffer, data, start, end) {
    if (inputIsString) {
      buffer.appendBinary(data.substring(start, end));
    } else {
      buffer.append(sliceShim(data, start, end));
    }
  }

  function loadNextChunk() {
    var start = currentChunk * chunkSize;
    var end = start + chunkSize;
    currentChunk++;
    if (currentChunk < chunks) {
      append(buffer, data, start, end);
      setImmediateShim(loadNextChunk);
    } else {
      append(buffer, data, start, end);
      var raw = buffer.end(true);
      var base64 = rawToBase64(raw);
      callback(null, base64);
      buffer.destroy();
    }
  }
  loadNextChunk();
};

}).call(this,_dereq_(37),typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{}],21:[function(_dereq_,module,exports){
'use strict';

//
// Parsing hex strings. Yeah.
//
// So basically we need this because of a bug in WebSQL:
// https://code.google.com/p/chromium/issues/detail?id=422690
// https://bugs.webkit.org/show_bug.cgi?id=137637
//
// UTF-8 and UTF-16 are provided as separate functions
// for meager performance improvements
//

function decodeUtf8(str) {
  return decodeURIComponent(window.escape(str));
}

function hexToInt(charCode) {
  // '0'-'9' is 48-57
  // 'A'-'F' is 65-70
  // SQLite will only give us uppercase hex
  return charCode < 65 ? (charCode - 48) : (charCode - 55);
}


// Example:
// pragma encoding=utf8;
// select hex('A');
// returns '41'
function parseHexUtf8(str, start, end) {
  var result = '';
  while (start < end) {
    result += String.fromCharCode(
      (hexToInt(str.charCodeAt(start++)) << 4) |
        hexToInt(str.charCodeAt(start++)));
  }
  return result;
}

// Example:
// pragma encoding=utf16;
// select hex('A');
// returns '4100'
// notice that the 00 comes after the 41 (i.e. it's swizzled)
function parseHexUtf16(str, start, end) {
  var result = '';
  while (start < end) {
    // UTF-16, so swizzle the bytes
    result += String.fromCharCode(
      (hexToInt(str.charCodeAt(start + 2)) << 12) |
        (hexToInt(str.charCodeAt(start + 3)) << 8) |
        (hexToInt(str.charCodeAt(start)) << 4) |
        hexToInt(str.charCodeAt(start + 1)));
    start += 4;
  }
  return result;
}

function parseHexString(str, encoding) {
  if (encoding === 'UTF-8') {
    return decodeUtf8(parseHexUtf8(str, 0, str.length));
  } else {
    return parseHexUtf16(str, 0, str.length);
  }
}

module.exports = parseHexString;
},{}],22:[function(_dereq_,module,exports){
'use strict';

// originally parseUri 1.2.2, now patched by us
// (c) Steven Levithan 
// MIT License
var options = {
  strictMode: false,
  key: ["source", "protocol", "authority", "userInfo", "user", "password",
    "host", "port", "relative", "path", "directory", "file", "query",
    "anchor"],
  q:   {
    name:   "queryKey",
    parser: /(?:^|&)([^&=]*)=?([^&]*)/g
  },
  parser: {
    /* jshint maxlen: false */
    strict: /^(?:([^:\/?#]+):)?(?:\/\/((?:(([^:@]*)(?::([^:@]*))?)?@)?([^:\/?#]*)(?::(\d*))?))?((((?:[^?#\/]*\/)*)([^?#]*))(?:\?([^#]*))?(?:#(.*))?)/,
    loose:  /^(?:(?![^:@]+:[^:@\/]*@)([^:\/?#.]+):)?(?:\/\/)?((?:(([^:@]*)(?::([^:@]*))?)?@)?([^:\/?#]*)(?::(\d*))?)(((\/(?:[^?#](?![^?#\/]*\.[^?#\/.]+(?:[?#]|$)))*\/?)?([^?#\/]*))(?:\?([^#]*))?(?:#(.*))?)/
  }
};
function parseUri(str) {
  var o = options;
  var m = o.parser[o.strictMode ? "strict" : "loose"].exec(str);
  var uri = {};
  var i = 14;

  while (i--) {
    var key = o.key[i];
    var value = m[i] || "";
    var encoded = ['user', 'password'].indexOf(key) !== -1;
    uri[key] = encoded ? decodeURIComponent(value) : value;
  }

  uri[o.q.name] = {};
  uri[o.key[12]].replace(o.q.parser, function ($0, $1, $2) {
    if ($1) {
      uri[o.q.name][$1] = $2;
    }
  });

  return uri;
}


module.exports = parseUri;
},{}],23:[function(_dereq_,module,exports){
'use strict';

var upsert = _dereq_(95).upsert;

module.exports = function (db, doc, diffFun, cb) {
  return upsert.call(db, doc, diffFun, cb);
};

},{}],24:[function(_dereq_,module,exports){
"use strict";

// BEGIN Math.uuid.js

/*!
Math.uuid.js (v1.4)
http://www.broofa.com
mailto:[email protected]

Copyright (c) 2010 Robert Kieffer
Dual licensed under the MIT and GPL licenses.
*/

/*
 * Generate a random uuid.
 *
 * USAGE: Math.uuid(length, radix)
 *   length - the desired number of characters
 *   radix  - the number of allowable values for each character.
 *
 * EXAMPLES:
 *   // No arguments  - returns RFC4122, version 4 ID
 *   >>> Math.uuid()
 *   "92329D39-6F5C-4520-ABFC-AAB64544E172"
 *
 *   // One argument - returns ID of the specified length
 *   >>> Math.uuid(15)     // 15 character ID (default base=62)
 *   "VcydxgltxrVZSTV"
 *
 *   // Two arguments - returns ID of the specified length, and radix. 
 *   // (Radix must be <= 62)
 *   >>> Math.uuid(8, 2)  // 8 character ID (base=2)
 *   "01001010"
 *   >>> Math.uuid(8, 10) // 8 character ID (base=10)
 *   "47473046"
 *   >>> Math.uuid(8, 16) // 8 character ID (base=16)
 *   "098F4D35"
 */
var chars = (
  '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ' +
  'abcdefghijklmnopqrstuvwxyz'
).split('');
function getValue(radix) {
  return 0 | Math.random() * radix;
}
function uuid(len, radix) {
  radix = radix || chars.length;
  var out = '';
  var i = -1;

  if (len) {
    // Compact form
    while (++i < len) {
      out += chars[getValue(radix)];
    }
    return out;
  }
    // rfc4122, version 4 form
    // Fill in random data.  At i==19 set the high bits of clock sequence as
    // per rfc4122, sec. 4.1.5
  while (++i < 36) {
    switch (i) {
      case 8:
      case 13:
      case 18:
      case 23:
        out += '-';
        break;
      case 19:
        out += chars[(getValue(16) & 0x3) | 0x8];
        break;
      default:
        out += chars[getValue(16)];
    }
  }

  return out;
}



module.exports = uuid;


},{}],25:[function(_dereq_,module,exports){
'use strict';

module.exports = evalFilter;
function evalFilter(input) {
  /*jshint evil: true */
  return eval([
    '(function () { return ',
    input,
    ' })()'
  ].join(''));
}
},{}],26:[function(_dereq_,module,exports){
'use strict';

module.exports = evalView;
function evalView(input) {
  /*jshint evil: true */
  return eval([
    '(function () {',
    '  return function (doc) {',
    '    var emitted = false;',
    '    var emit = function (a, b) {',
    '      emitted = true;',
    '    };',
    '    var view = ' + input + ';',
    '    view(doc);',
    '    if (emitted) {',
    '      return true;',
    '    }',
    '  }',
    '})()'
  ].join('\n'));
}
},{}],27:[function(_dereq_,module,exports){
'use strict';
var extend = _dereq_(63);


// for a better overview of what this is doing, read:
// https://github.com/apache/couchdb/blob/master/src/couchdb/couch_key_tree.erl
//
// But for a quick intro, CouchDB uses a revision tree to store a documents
// history, A -> B -> C, when a document has conflicts, that is a branch in the
// tree, A -> (B1 | B2 -> C), We store these as a nested array in the format
//
// KeyTree = [Path ... ]
// Path = {pos: position_from_root, ids: Tree}
// Tree = [Key, Opts, [Tree, ...]], in particular single node: [Key, []]

// classic binary search
function binarySearch(arr, item, comparator) {
  var low = 0;
  var high = arr.length;
  var mid;
  while (low < high) {
    mid = (low + high) >>> 1;
    if (comparator(arr[mid], item) < 0) {
      low = mid + 1;
    } else {
      high = mid;
    }
  }
  return low;
}

// assuming the arr is sorted, insert the item in the proper place
function insertSorted(arr, item, comparator) {
  var idx = binarySearch(arr, item, comparator);
  arr.splice(idx, 0, item);
}

// Turn a path as a flat array into a tree with a single branch
function pathToTree(path) {
  var doc = path.shift();
  var root = [doc.id, doc.opts, []];
  var leaf = root;
  var nleaf;

  while (path.length) {
    doc = path.shift();
    nleaf = [doc.id, doc.opts, []];
    leaf[2].push(nleaf);
    leaf = nleaf;
  }
  return root;
}

// compare the IDs of two trees
function compareTree(a, b) {
  return a[0] < b[0] ? -1 : 1;
}

// Merge two trees together
// The roots of tree1 and tree2 must be the same revision
function mergeTree(in_tree1, in_tree2) {
  var queue = [{tree1: in_tree1, tree2: in_tree2}];
  var conflicts = false;
  while (queue.length > 0) {
    var item = queue.pop();
    var tree1 = item.tree1;
    var tree2 = item.tree2;

    if (tree1[1].status || tree2[1].status) {
      tree1[1].status =
        (tree1[1].status ===  'available' ||
         tree2[1].status === 'available') ? 'available' : 'missing';
    }

    for (var i = 0; i < tree2[2].length; i++) {
      if (!tree1[2][0]) {
        conflicts = 'new_leaf';
        tree1[2][0] = tree2[2][i];
        continue;
      }

      var merged = false;
      for (var j = 0; j < tree1[2].length; j++) {
        if (tree1[2][j][0] === tree2[2][i][0]) {
          queue.push({tree1: tree1[2][j], tree2: tree2[2][i]});
          merged = true;
        }
      }
      if (!merged) {
        conflicts = 'new_branch';
        insertSorted(tree1[2], tree2[2][i], compareTree);
      }
    }
  }
  return {conflicts: conflicts, tree: in_tree1};
}

function doMerge(tree, path, dontExpand) {
  var restree = [];
  var conflicts = false;
  var merged = false;
  var res;

  if (!tree.length) {
    return {tree: [path], conflicts: 'new_leaf'};
  }

  tree.forEach(function (branch) {
    if (branch.pos === path.pos && branch.ids[0] === path.ids[0]) {
      // Paths start at the same position and have the same root, so they need
      // merged
      res = mergeTree(branch.ids, path.ids);
      restree.push({pos: branch.pos, ids: res.tree});
      conflicts = conflicts || res.conflicts;
      merged = true;
    } else if (dontExpand !== true) {
      // The paths start at a different position, take the earliest path and
      // traverse up until it as at the same point from root as the path we
      // want to merge.  If the keys match we return the longer path with the
      // other merged After stemming we dont want to expand the trees

      var t1 = branch.pos < path.pos ? branch : path;
      var t2 = branch.pos < path.pos ? path : branch;
      var diff = t2.pos - t1.pos;

      var candidateParents = [];

      var trees = [];
      trees.push({ids: t1.ids, diff: diff, parent: null, parentIdx: null});
      while (trees.length > 0) {
        var item = trees.pop();
        if (item.diff === 0) {
          if (item.ids[0] === t2.ids[0]) {
            candidateParents.push(item);
          }
          continue;
        }
        if (!item.ids) {
          continue;
        }
        /*jshint loopfunc:true */
        item.ids[2].forEach(function (el, idx) {
          trees.push(
            {ids: el, diff: item.diff - 1, parent: item.ids, parentIdx: idx});
        });
      }

      var el = candidateParents[0];

      if (!el) {
        restree.push(branch);
      } else {
        res = mergeTree(el.ids, t2.ids);
        el.parent[2][el.parentIdx] = res.tree;
        restree.push({pos: t1.pos, ids: t1.ids});
        conflicts = conflicts || res.conflicts;
        merged = true;
      }
    } else {
      restree.push(branch);
    }
  });

  // We didnt find
  if (!merged) {
    restree.push(path);
  }

  restree.sort(function (a, b) {
    return a.pos - b.pos;
  });

  return {
    tree: restree,
    conflicts: conflicts || 'internal_node'
  };
}

// To ensure we dont grow the revision tree infinitely, we stem old revisions
function stem(tree, depth) {
  // First we break out the tree into a complete list of root to leaf paths,
  // we cut off the start of the path and generate a new set of flat trees
  var stemmedPaths = PouchMerge.rootToLeaf(tree).map(function (path) {
    var stemmed = path.ids.slice(-depth);
    return {
      pos: path.pos + (path.ids.length - stemmed.length),
      ids: pathToTree(stemmed)
    };
  });
  // Then we remerge all those flat trees together, ensuring that we dont
  // connect trees that would go beyond the depth limit
  return stemmedPaths.reduce(function (prev, current) {
    return doMerge(prev, current, true).tree;
  }, [stemmedPaths.shift()]);
}

var PouchMerge = {};

PouchMerge.merge = function (tree, path, depth) {
  // Ugh, nicer way to not modify arguments in place?
  tree = extend(true, [], tree);
  path = extend(true, {}, path);
  var newTree = doMerge(tree, path);
  return {
    tree: stem(newTree.tree, depth),
    conflicts: newTree.conflicts
  };
};

// We fetch all leafs of the revision tree, and sort them based on tree length
// and whether they were deleted, undeleted documents with the longest revision
// tree (most edits) win
// The final sort algorithm is slightly documented in a sidebar here:
// http://guide.couchdb.org/draft/conflicts.html
PouchMerge.winningRev = function (metadata) {
  var leafs = [];
  PouchMerge.traverseRevTree(metadata.rev_tree,
                              function (isLeaf, pos, id, something, opts) {
    if (isLeaf) {
      leafs.push({pos: pos, id: id, deleted: !!opts.deleted});
    }
  });
  leafs.sort(function (a, b) {
    if (a.deleted !== b.deleted) {
      return a.deleted > b.deleted ? 1 : -1;
    }
    if (a.pos !== b.pos) {
      return b.pos - a.pos;
    }
    return a.id < b.id ? 1 : -1;
  });

  return leafs[0].pos + '-' + leafs[0].id;
};

// Pretty much all below can be combined into a higher order function to
// traverse revisions
// The return value from the callback will be passed as context to all
// children of that node
PouchMerge.traverseRevTree = function (revs, callback) {
  var toVisit = revs.slice();

  var node;
  while ((node = toVisit.pop())) {
    var pos = node.pos;
    var tree = node.ids;
    var branches = tree[2];
    var newCtx =
      callback(branches.length === 0, pos, tree[0], node.ctx, tree[1]);
    for (var i = 0, len = branches.length; i < len; i++) {
      toVisit.push({pos: pos + 1, ids: branches[i], ctx: newCtx});
    }
  }
};

PouchMerge.collectLeaves = function (revs) {
  var leaves = [];
  PouchMerge.traverseRevTree(revs, function (isLeaf, pos, id, acc, opts) {
    if (isLeaf) {
      leaves.push({rev: pos + "-" + id, pos: pos, opts: opts});
    }
  });
  leaves.sort(function (a, b) {
    return b.pos - a.pos;
  });
  leaves.forEach(function (leaf) { delete leaf.pos; });
  return leaves;
};

// returns revs of all conflicts that is leaves such that
// 1. are not deleted and
// 2. are different than winning revision
PouchMerge.collectConflicts = function (metadata) {
  var win = PouchMerge.winningRev(metadata);
  var leaves = PouchMerge.collectLeaves(metadata.rev_tree);
  var conflicts = [];
  leaves.forEach(function (leaf) {
    if (leaf.rev !== win && !leaf.opts.deleted) {
      conflicts.push(leaf.rev);
    }
  });
  return conflicts;
};

PouchMerge.rootToLeaf = function (tree) {
  var paths = [];
  PouchMerge.traverseRevTree(tree, function (isLeaf, pos, id, history, opts) {
    history = history ? history.slice(0) : [];
    history.push({id: id, opts: opts});
    if (isLeaf) {
      var rootPos = pos + 1 - history.length;
      paths.unshift({pos: rootPos, ids: history});
    }
    return history;
  });
  return paths;
};


module.exports = PouchMerge;

},{}],28:[function(_dereq_,module,exports){
'use strict';

var utils = _dereq_(32);
var EE = _dereq_(36).EventEmitter;
var Checkpointer = _dereq_(14);

var MAX_SIMULTANEOUS_REVS = 50;
var RETRY_DEFAULT = false;

function randomNumber(min, max) {
  min = parseInt(min, 10);
  max = parseInt(max, 10);
  if (min !== min) {
    min = 0;
  }
  if (max !== max || max <= min) {
    max = (min || 1) << 1; //doubling
  } else {
    max = max + 1;
  }
  var ratio = Math.random();
  var range = max - min;

  return ~~(range * ratio + min); // ~~ coerces to an int, but fast.
}

function defaultBackOff(min) {
  var max = 0;
  if (!min) {
    max = 2000;
  }
  return randomNumber(min, max);
}

function backOff(repId, src, target, opts, returnValue, result, error) {
  if (opts.retry === false) {
    returnValue.emit('error', error);
    returnValue.removeAllListeners();
    return;
  }
  opts.default_back_off = opts.default_back_off || 0;
  opts.retries = opts.retries || 0;
  if (typeof opts.back_off_function !== 'function') {
    opts.back_off_function = defaultBackOff;
  }
  opts.retries++;
  if (opts.max_retries && opts.retries > opts.max_retries) {
    returnValue.emit('error', new Error('tried ' +
      opts.retries + ' times but replication failed'));
    returnValue.removeAllListeners();
    return;
  }
  returnValue.emit('requestError', error);
  if (returnValue.state === 'active') {
    returnValue.emit('paused', error);
    returnValue.state = 'stopped';
    returnValue.once('active', function () {
      opts.current_back_off = opts.default_back_off;
    });
  }

  opts.current_back_off = opts.current_back_off || opts.default_back_off;
  opts.current_back_off = opts.back_off_function(opts.current_back_off);
  setTimeout(function () {
    replicate(repId, src, target, opts, returnValue);
  }, opts.current_back_off);
}

// We create a basic promise so the caller can cancel the replication possibly
// before we have actually started listening to changes etc
utils.inherits(Replication, EE);
function Replication() {
  EE.call(this);
  this.cancelled = false;
  this.state = 'pending';
  var self = this;
  var promise = new utils.Promise(function (fulfill, reject) {
    self.once('complete', fulfill);
    self.once('error', reject);
  });
  self.then = function (resolve, reject) {
    return promise.then(resolve, reject);
  };
  self["catch"] = function (reject) {
    return promise["catch"](reject);
  };
  // As we allow error handling via "error" event as well,
  // put a stub in here so that rejecting never throws UnhandledError.
  self["catch"](function () {});
}

Replication.prototype.cancel = function () {
  this.cancelled = true;
  this.state = 'cancelled';
  this.emit('cancel');
};

Replication.prototype.ready = function (src, target) {
  var self = this;
  this.once('change', function () {
    if (this.state === 'pending' || this.state === 'stopped') {
      self.state = 'active';
      self.emit('active');
    }
  });
  function onDestroy() {
    self.cancel();
  }
  src.once('destroyed', onDestroy);
  target.once('destroyed', onDestroy);
  function cleanup() {
    src.removeListener('destroyed', onDestroy);
    target.removeListener('destroyed', onDestroy);
  }
  this.then(cleanup, cleanup);
};


// TODO: check CouchDB's replication id generation
// Generate a unique id particular to this replication
function genReplicationId(src, target, opts) {
  var filterFun = opts.filter ? opts.filter.toString() : '';
  return src.id().then(function (src_id) {
    return target.id().then(function (target_id) {
      var queryData = src_id + target_id + filterFun +
        JSON.stringify(opts.query_params) + opts.doc_ids;
      return utils.MD5(queryData).then(function (md5) {
        // can't use straight-up md5 alphabet, because
        // the char '/' is interpreted as being for attachments,
        // and + is also not url-safe
        md5 = md5.replace(/\//g, '.').replace(/\+/g, '_');
        return '_local/' + md5;
      });
    });
  });
}

function replicate(repId, src, target, opts, returnValue, result) {
  var batches = [];               // list of batches to be processed
  var currentBatch;               // the batch currently being processed
  var pendingBatch = {
    seq: 0,
    changes: [],
    docs: []
  }; // next batch, not yet ready to be processed
  var writingCheckpoint = false;  // true while checkpoint is being written
  var changesCompleted = false;   // true when all changes received
  var replicationCompleted = false; // true when replication has completed
  var last_seq = 0;
  var continuous = opts.continuous || opts.live || false;
  var batch_size = opts.batch_size || 100;
  var batches_limit = opts.batches_limit || 10;
  var changesPending = false;     // true while src.changes is running
  var doc_ids = opts.doc_ids;
  var state = {
    cancelled: false
  };
  var checkpointer = new Checkpointer(src, target, repId, state);
  var allErrors = [];
  var changedDocs = [];

  result = result || {
    ok: true,
    start_time: new Date(),
    docs_read: 0,
    docs_written: 0,
    doc_write_failures: 0,
    errors: []
  };

  var changesOpts = {};
  returnValue.ready(src, target);

  function writeDocs() {
    if (currentBatch.docs.length === 0) {
      return;
    }
    var docs = currentBatch.docs;
    return target.bulkDocs({docs: docs, new_edits: false}).then(function (res) {
      if (state.cancelled) {
        completeReplication();
        throw new Error('cancelled');
      }
      var errors = [];
      var errorsById = {};
      res.forEach(function (res) {
        if (res.error) {
          result.doc_write_failures++;
          errors.push(res);
          errorsById[res.id] = res;
        }
      });
      result.errors = errors;
      allErrors = allErrors.concat(errors);
      result.docs_written += currentBatch.docs.length - errors.length;
      var non403s = errors.filter(function (error) {
        return error.name !== 'unauthorized' && error.name !== 'forbidden';
      });

      changedDocs = [];
      docs.forEach(function(doc) {
        var error = errorsById[doc._id];
        if (error) {
          returnValue.emit('denied', utils.clone(error));
        } else {
          changedDocs.push(doc);
        }
      });

      if (non403s.length > 0) {
        var error = new Error('bulkDocs error');
        error.other_errors = errors;
        abortReplication('target.bulkDocs failed to write docs', error);
        throw new Error('bulkWrite partial failure');
      }
    }, function (err) {
      result.doc_write_failures += docs.length;
      throw err;
    });
  }

  function processDiffDoc(id) {
    var diffs = currentBatch.diffs;
    var allMissing = diffs[id].missing;
    // avoid url too long error by batching
    var missingBatches = [];
    for (var i = 0; i < allMissing.length; i += MAX_SIMULTANEOUS_REVS) {
      missingBatches.push(allMissing.slice(i, Math.min(allMissing.length,
        i + MAX_SIMULTANEOUS_REVS)));
    }

    return utils.Promise.all(missingBatches.map(function (missing) {
      var opts = {
        revs: true,
        open_revs: missing,
        attachments: true
      };
      return src.get(id, opts).then(function (docs) {
        docs.forEach(function (doc) {
          if (state.cancelled) {
            return completeReplication();
          }
          if (doc.ok) {
            result.docs_read++;
            currentBatch.pendingRevs++;
            currentBatch.docs.push(doc.ok);
          }
        });
        delete diffs[id];
      });
    }));
  }

  function getAllDocs() {
    var diffKeys = Object.keys(currentBatch.diffs);
    return utils.Promise.all(diffKeys.map(processDiffDoc));
  }


  function getRevisionOneDocs() {
    // filter out the generation 1 docs and get them
    // leaving the non-generation one docs to be got otherwise
    var ids = Object.keys(currentBatch.diffs).filter(function (id) {
      var missing = currentBatch.diffs[id].missing;
      return missing.length === 1 && missing[0].slice(0, 2) === '1-';
    });
    if (!ids.length) { // nothing to fetch
      return utils.Promise.resolve();
    }
    return src.allDocs({
      keys: ids,
      include_docs: true
    }).then(function (res) {
      if (state.cancelled) {
        completeReplication();
        throw (new Error('cancelled'));
      }
      res.rows.forEach(function (row) {
        if (row.doc && !row.deleted &&
          row.value.rev.slice(0, 2) === '1-' && (
            !row.doc._attachments ||
            Object.keys(row.doc._attachments).length === 0
          )
        ) {
          result.docs_read++;
          currentBatch.pendingRevs++;
          currentBatch.docs.push(row.doc);
          delete currentBatch.diffs[row.id];
        }
      });
    });
  }

  function getDocs() {
    return getRevisionOneDocs().then(getAllDocs);
  }

  function finishBatch() {
    writingCheckpoint = true;
    return checkpointer.writeCheckpoint(currentBatch.seq).then(function () {
      writingCheckpoint = false;
      if (state.cancelled) {
        completeReplication();
        throw new Error('cancelled');
      }
      result.last_seq = last_seq = currentBatch.seq;
      var outResult = utils.clone(result);
      outResult.docs = changedDocs;
      returnValue.emit('change', outResult);
      currentBatch = undefined;
      getChanges();
    })["catch"](function (err) {
      writingCheckpoint = false;
      abortReplication('writeCheckpoint completed with error', err);
      throw err;
    });
  }

  function getDiffs() {
    var diff = {};
    currentBatch.changes.forEach(function (change) {
      diff[change.id] = change.changes.map(function (x) {
        return x.rev;
      });
    });
    return target.revsDiff(diff).then(function (diffs) {
      if (state.cancelled) {
        completeReplication();
        throw new Error('cancelled');
      }
      // currentBatch.diffs elements are deleted as the documents are written
      currentBatch.diffs = diffs;
      currentBatch.pendingRevs = 0;
    });
  }

  function startNextBatch() {
    if (state.cancelled || currentBatch) {
      return;
    }
    if (batches.length === 0) {
      processPendingBatch(true);
      return;
    }
    currentBatch = batches.shift();
    getDiffs()
      .then(getDocs)
      .then(writeDocs)
      .then(finishBatch)
      .then(startNextBatch)[
      "catch"](function (err) {
        abortReplication('batch processing terminated with error', err);
      });
  }


  function processPendingBatch(immediate) {
    if (pendingBatch.changes.length === 0) {
      if (batches.length === 0 && !currentBatch) {
        if ((continuous && changesOpts.live) || changesCompleted) {
          returnValue.emit('paused');
          returnValue.emit('uptodate', result);
        }
        if (changesCompleted) {
          completeReplication();
        }
      }
      return;
    }
    if (
      immediate ||
      changesCompleted ||
      pendingBatch.changes.length >= batch_size
    ) {
      batches.push(pendingBatch);
      pendingBatch = {
        seq: 0,
        changes: [],
        docs: []
      };
      startNextBatch();
    }
  }


  function abortReplication(reason, err) {
    if (replicationCompleted) {
      return;
    }
    if (!err.message) {
      err.message = reason;
    }
    result.ok = false;
    result.status = 'aborting';
    result.errors.push(err);
    allErrors = allErrors.concat(err);
    batches = [];
    pendingBatch = {
      seq: 0,
      changes: [],
      docs: []
    };
    completeReplication();
  }


  function completeReplication() {
    if (replicationCompleted) {
      return;
    }
    if (state.cancelled) {
      result.status = 'cancelled';
      if (writingCheckpoint) {
        return;
      }
    }
    result.status = result.status || 'complete';
    result.end_time = new Date();
    result.last_seq = last_seq;
    replicationCompleted = state.cancelled = true;
    var non403s = allErrors.filter(function (error) {
      return error.name !== 'unauthorized' && error.name !== 'forbidden';
    });
    if (non403s.length > 0) {
      var error = allErrors.pop();
      if (allErrors.length > 0) {
        error.other_errors = allErrors;
      }
      error.result = result;
      backOff(repId, src, target, opts, returnValue, result, error);
    } else {
      result.errors = allErrors;
      returnValue.emit('complete', result);
      returnValue.removeAllListeners();
    }
  }


  function onChange(change) {
    if (state.cancelled) {
      return completeReplication();
    }
    var filter = utils.filterChange(opts)(change);
    if (!filter) {
      return;
    }
    if (
      pendingBatch.changes.length === 0 &&
      batches.length === 0 &&
      !currentBatch
    ) {
      returnValue.emit('outofdate', result);
    }
    pendingBatch.seq = change.seq;
    pendingBatch.changes.push(change);
    processPendingBatch(batches.length === 0);
  }


  function onChangesComplete(changes) {
    changesPending = false;
    if (state.cancelled) {
      return completeReplication();
    }

    // if no results were returned then we're done,
    // else fetch more
    if (changes.results.length > 0) {
      changesOpts.since = changes.last_seq;
      getChanges();
    } else {
      if (continuous) {
        changesOpts.live = true;
        getChanges();
      } else {
        changesCompleted = true;
      }
    }
    processPendingBatch(true);
  }


  function onChangesError(err) {
    changesPending = false;
    if (state.cancelled) {
      return completeReplication();
    }
    abortReplication('changes rejected', err);
  }


  function getChanges() {
    if (!(
      !changesPending &&
      !changesCompleted &&
      batches.length < batches_limit
    )) {
      return;
    }
    changesPending = true;
    function abortChanges() {
      changes.cancel();
    }
    function removeListener() {
      returnValue.removeListener('cancel', abortChanges);
    }
    returnValue.once('cancel', abortChanges);
    var changes = src.changes(changesOpts)
    .on('change', onChange);
    changes.then(removeListener, removeListener);
    changes.then(onChangesComplete)[
    "catch"](onChangesError);
  }


  function startChanges() {
    checkpointer.getCheckpoint().then(function (checkpoint) {
      last_seq = checkpoint;
      changesOpts = {
        since: last_seq,
        limit: batch_size,
        batch_size: batch_size,
        style: 'all_docs',
        doc_ids: doc_ids,
        returnDocs: true // required so we know when we're done
      };
      if (opts.filter) {
        // required for the client-side filter in onChange
        changesOpts.include_docs = true;
      }
      if (opts.query_params) {
        changesOpts.query_params = opts.query_params;
      }
      getChanges();
    })["catch"](function (err) {
      abortReplication('getCheckpoint rejected with ', err);
    });
  }


  returnValue.once('cancel', completeReplication);

  if (typeof opts.onChange === 'function') {
    returnValue.on('change', opts.onChange);
  }

  if (typeof opts.complete === 'function') {
    returnValue.once('error', opts.complete);
    returnValue.once('complete', function (result) {
      opts.complete(null, result);
    });
  }

  if (typeof opts.since === 'undefined') {
    startChanges();
  } else {
    writingCheckpoint = true;
    checkpointer.writeCheckpoint(opts.since).then(function () {
      writingCheckpoint = false;
      if (state.cancelled) {
        completeReplication();
        return;
      }
      last_seq = opts.since;
      startChanges();
    })["catch"](function (err) {
      writingCheckpoint = false;
      abortReplication('writeCheckpoint completed with error', err);
      throw err;
    });
  }
}

exports.toPouch = toPouch;
function toPouch(db, opts) {
  var PouchConstructor = opts.PouchConstructor;
  if (typeof db === 'string') {
    return new PouchConstructor(db);
  } else if (db.then) {
    return db;
  } else {
    return utils.Promise.resolve(db);
  }
}


exports.replicate = replicateWrapper;
function replicateWrapper(src, target, opts, callback) {
  if (typeof opts === 'function') {
    callback = opts;
    opts = {};
  }
  if (typeof opts === 'undefined') {
    opts = {};
  }
  if (!opts.complete) {
    opts.complete = callback || function () {};
  }
  opts = utils.clone(opts);
  opts.continuous = opts.continuous || opts.live;
  opts.retry = ('retry' in opts) ? opts.retry : RETRY_DEFAULT;
  /*jshint validthis:true */
  opts.PouchConstructor = opts.PouchConstructor || this;
  var replicateRet = new Replication(opts);
  toPouch(src, opts).then(function (src) {
    return toPouch(target, opts).then(function (target) {
      return genReplicationId(src, target, opts).then(function (repId) {
        replicate(repId, src, target, opts, replicateRet);
      });
    });
  })["catch"](function (err) {
    replicateRet.emit('error', err);
    opts.complete(err);
  });
  return replicateRet;
}

},{}],29:[function(_dereq_,module,exports){
"use strict";

var PouchDB = _dereq_(15);
var utils = _dereq_(32);
var Promise = utils.Promise;
var EventEmitter = _dereq_(36).EventEmitter;
PouchDB.adapters = {};
PouchDB.preferredAdapters = _dereq_(8);

PouchDB.prefix = '_pouch_';

var eventEmitter = new EventEmitter();

var eventEmitterMethods = [
  'on',
  'addListener',
  'emit',
  'listeners',
  'once',
  'removeAllListeners',
  'removeListener',
  'setMaxListeners'
];

eventEmitterMethods.forEach(function (method) {
  PouchDB[method] = eventEmitter[method].bind(eventEmitter);
});
PouchDB.setMaxListeners(0);
PouchDB.parseAdapter = function (name, opts) {
  var match = name.match(/([a-z\-]*):\/\/(.*)/);
  var adapter, adapterName;
  if (match) {
    // the http adapter expects the fully qualified name
    name = /http(s?)/.test(match[1]) ? match[1] + '://' + match[2] : match[2];
    adapter = match[1];
    if (!PouchDB.adapters[adapter].valid()) {
      throw 'Invalid adapter';
    }
    return {name: name, adapter: match[1]};
  }

  // check for browsers that have been upgraded from websql-only to websql+idb
  var skipIdb = 'idb' in PouchDB.adapters && 'websql' in PouchDB.adapters &&
    utils.hasLocalStorage() &&
    localStorage['_pouch__websqldb_' + PouchDB.prefix + name];

  if (typeof opts !== 'undefined' && opts.db) {
    adapterName = 'leveldb';
  } else {
    for (var i = 0; i < PouchDB.preferredAdapters.length; ++i) {
      adapterName = PouchDB.preferredAdapters[i];
      if (adapterName in PouchDB.adapters) {
        if (skipIdb && adapterName === 'idb') {
          continue; // keep using websql to avoid user data loss
        }
        break;
      }
    }
  }

  adapter = PouchDB.adapters[adapterName];
  if (adapterName && adapter) {
    var use_prefix = 'use_prefix' in adapter ? adapter.use_prefix : true;

    return {
      name: use_prefix ? PouchDB.prefix + name : name,
      adapter: adapterName
    };
  }

  throw 'No valid adapter found';
};

PouchDB.destroy = utils.toPromise(function (name, opts, callback) {

  if (typeof opts === 'function' || typeof opts === 'undefined') {
    callback = opts;
    opts = {};
  }
  if (name && typeof name === 'object') {
    opts = name;
    name = undefined;
  }

  if (!opts.internal) {
    console.log('PouchDB.destroy() is deprecated and will be removed. ' +
                'Please use db.destroy() instead.');
  }

  var backend = PouchDB.parseAdapter(opts.name || name, opts);
  var dbName = backend.name;
  var adapter = PouchDB.adapters[backend.adapter];
  var usePrefix = 'use_prefix' in adapter ? adapter.use_prefix : true;
  var baseName = usePrefix ?
    dbName.replace(new RegExp('^' + PouchDB.prefix), '') : dbName;
  var fullName = (backend.adapter === 'http' || backend.adapter === 'https' ?
      '' : (opts.prefix || '')) + dbName;
  function destroyDb() {
    // call destroy method of the particular adaptor
    adapter.destroy(fullName, opts, function (err, resp) {
      if (err) {
        callback(err);
      } else {
        PouchDB.emit('destroyed', name);
        //so we don't have to sift through all dbnames
        PouchDB.emit(name, 'destroyed');
        callback(null, resp || { 'ok': true });
      }
    });
  }

  var createOpts = utils.extend(true, {}, opts, {adapter : backend.adapter});
  new PouchDB(baseName, createOpts, function (err, db) {
    if (err) {
      return callback(err);
    }
    db.get('_local/_pouch_dependentDbs', function (err, localDoc) {
      if (err) {
        if (err.status !== 404) {
          return callback(err);
        } else { // no dependencies
          return destroyDb();
        }
      }
      var dependentDbs = localDoc.dependentDbs;
      var deletedMap = Object.keys(dependentDbs).map(function (name) {
        var trueName = usePrefix ?
          name.replace(new RegExp('^' + PouchDB.prefix), '') : name;
        var subOpts = utils.extend(true, opts, db.__opts || {});
        return db.constructor.destroy(trueName, subOpts);
      });
      Promise.all(deletedMap).then(destroyDb, function (error) {
        callback(error);
      });
    });
  });
});

PouchDB.adapter = function (id, obj) {
  if (obj.valid()) {
    PouchDB.adapters[id] = obj;
  }
};

PouchDB.plugin = function (obj) {
  Object.keys(obj).forEach(function (id) {
    PouchDB.prototype[id] = obj[id];
  });
};

PouchDB.defaults = function (defaultOpts) {
  function PouchAlt(name, opts, callback) {
    if (typeof opts === 'function' || typeof opts === 'undefined') {
      callback = opts;
      opts = {};
    }
    if (name && typeof name === 'object') {
      opts = name;
      name = undefined;
    }

    opts = utils.extend(true, {}, defaultOpts, opts);
    PouchDB.call(this, name, opts, callback);
  }

  utils.inherits(PouchAlt, PouchDB);

  PouchAlt.destroy = utils.toPromise(function (name, opts, callback) {
    if (typeof opts === 'function' || typeof opts === 'undefined') {
      callback = opts;
      opts = {};
    }

    if (name && typeof name === 'object') {
      opts = name;
      name = undefined;
    }
    opts = utils.extend(true, {}, defaultOpts, opts);
    return PouchDB.destroy(name, opts, callback);
  });

  eventEmitterMethods.forEach(function (method) {
    PouchAlt[method] = eventEmitter[method].bind(eventEmitter);
  });
  PouchAlt.setMaxListeners(0);

  PouchAlt.preferredAdapters = PouchDB.preferredAdapters.slice();
  Object.keys(PouchDB).forEach(function (key) {
    if (!(key in PouchAlt)) {
      PouchAlt[key] = PouchDB[key];
    }
  });

  return PouchAlt;
};

module.exports = PouchDB;

},{}],30:[function(_dereq_,module,exports){
'use strict';

var utils = _dereq_(32);
var replication = _dereq_(28);
var replicate = replication.replicate;
var EE = _dereq_(36).EventEmitter;

utils.inherits(Sync, EE);
module.exports = sync;
function sync(src, target, opts, callback) {
  if (typeof opts === 'function') {
    callback = opts;
    opts = {};
  }
  if (typeof opts === 'undefined') {
    opts = {};
  }
  opts = utils.clone(opts);
  /*jshint validthis:true */
  opts.PouchConstructor = opts.PouchConstructor || this;
  src = replication.toPouch(src, opts);
  target = replication.toPouch(target, opts);
  return new Sync(src, target, opts, callback);
}

function Sync(src, target, opts, callback) {
  var self = this;
  this.canceled = false;

  var onChange, complete;
  if ('onChange' in opts) {
    onChange = opts.onChange;
    delete opts.onChange;
  }
  if (typeof callback === 'function' && !opts.complete) {
    complete = callback;
  } else if ('complete' in opts) {
    complete = opts.complete;
    delete opts.complete;
  }

  this.push = replicate(src, target, opts);
  this.pull = replicate(target, src, opts);

  var emittedCancel = false;
  function onCancel(data) {
    if (!emittedCancel) {
      emittedCancel = true;
      self.emit('cancel', data);
    }
  }
  function pullChange(change) {
    self.emit('change', {
      direction: 'pull',
      change: change
    });
  }
  function pushChange(change) {
    self.emit('change', {
      direction: 'push',
      change: change
    });
  }
  function pushDenied(doc) {
    self.emit('denied', {
      direction: 'push',
      doc: doc
    });
  }
  function pullDenied(doc) {
    self.emit('denied', {
      direction: 'pull',
      doc: doc
    });
  }

  var listeners = {};
  var removed = {};

  function removeAll(type) { // type is 'push' or 'pull'
    return function (event, func) {
      var isChange = event === 'change' &&
        (func === pullChange || func === pushChange);
      var isCancel = event === 'cancel' && func === onCancel;
      var isOtherEvent = event in listeners && func === listeners[event];

      if (isChange || isCancel || isOtherEvent) {
        if (!(event in removed)) {
          removed[event] = {};
        }
        removed[event][type] = true;
        if (Object.keys(removed[event]).length === 2) {
          // both push and pull have asked to be removed
          self.removeAllListeners(event);
        }
      }
    };
  }

  if (opts.live) {
    this.push.on('complete', self.pull.cancel.bind(self.pull));
    this.pull.on('complete', self.push.cancel.bind(self.push));
  }

  this.on('newListener', function (event) {
    if (event === 'change') {
      self.pull.on('change', pullChange);
      self.push.on('change', pushChange);
    } else if (event === 'denied') {
      self.pull.on('denied', pullDenied);
      self.push.on('denied', pushDenied);
    } else if (event === 'cancel') {
      self.pull.on('cancel', onCancel);
      self.push.on('cancel', onCancel);
    } else if (event !== 'error' &&
      event !== 'removeListener' &&
      event !== 'complete' && !(event in listeners)) {
      listeners[event] = function (e) {
        self.emit(event, e);
      };
      self.pull.on(event, listeners[event]);
      self.push.on(event, listeners[event]);
    }
  });

  this.on('removeListener', function (event) {
    if (event === 'change') {
      self.pull.removeListener('change', pullChange);
      self.push.removeListener('change', pushChange);
    } else if (event === 'cancel') {
      self.pull.removeListener('cancel', onCancel);
      self.push.removeListener('cancel', onCancel);
    } else if (event in listeners) {
      if (typeof listeners[event] === 'function') {
        self.pull.removeListener(event, listeners[event]);
        self.push.removeListener(event, listeners[event]);
        delete listeners[event];
      }
    }
  });

  this.pull.on('removeListener', removeAll('pull'));
  this.push.on('removeListener', removeAll('push'));

  var promise = utils.Promise.all([
    this.push,
    this.pull
  ]).then(function (resp) {
    var out = {
      push: resp[0],
      pull: resp[1]
    };
    self.emit('complete', out);
    if (complete) {
      complete(null, out);
    }
    self.removeAllListeners();
    return out;
  }, function (err) {
    self.cancel();
    self.emit('error', err);
    if (complete) {
      complete(err);
    }
    self.removeAllListeners();
    throw err;
  });

  this.then = function (success, err) {
    return promise.then(success, err);
  };

  this["catch"] = function (err) {
    return promise["catch"](err);
  };
}

Sync.prototype.cancel = function () {
  if (!this.canceled) {
    this.canceled = true;
    this.push.cancel();
    this.pull.cancel();
  }
};

},{}],31:[function(_dereq_,module,exports){
'use strict';

module.exports = TaskQueue;

function TaskQueue() {
  this.isReady = false;
  this.failed = false;
  this.queue = [];
}

TaskQueue.prototype.execute = function () {
  var d, func;
  if (this.failed) {
    while ((d = this.queue.shift())) {
      if (typeof d === 'function') {
        d(this.failed);
        continue;
      }
      func = d.parameters[d.parameters.length - 1];
      if (typeof func === 'function') {
        func(this.failed);
      } else if (d.name === 'changes' && typeof func.complete === 'function') {
        func.complete(this.failed);
      }
    }
  } else if (this.isReady) {
    while ((d = this.queue.shift())) {

      if (typeof d === 'function') {
        d();
      } else {
        d.task = this.db[d.name].apply(this.db, d.parameters);
      }
    }
  }
};

TaskQueue.prototype.fail = function (err) {
  this.failed = err;
  this.execute();
};

TaskQueue.prototype.ready = function (db) {
  if (this.failed) {
    return false;
  } else if (arguments.length === 0) {
    return this.isReady;
  }
  this.isReady = db ? true: false;
  this.db = db;
  this.execute();
};

TaskQueue.prototype.addTask = function (name, parameters) {
  if (typeof name === 'function') {
    this.queue.push(name);
    if (this.failed) {
      this.execute();
    }
  } else {
    var task = { name: name, parameters: parameters };
    this.queue.push(task);
    if (this.failed) {
      this.execute();
    }
    return task;
  }
};

},{}],32:[function(_dereq_,module,exports){
(function (process,global){
/*jshint strict: false */
/*global chrome */
var merge = _dereq_(27);
exports.extend = _dereq_(63);
exports.ajax = _dereq_(16);
exports.createBlob = _dereq_(17);
exports.uuid = _dereq_(24);
exports.getArguments = _dereq_(34);
var buffer = _dereq_(18);
var errors = _dereq_(19);
var EventEmitter = _dereq_(36).EventEmitter;
var collections = _dereq_(62);
exports.Map = collections.Map;
exports.Set = collections.Set;

if (typeof global.Promise === 'function') {
  exports.Promise = global.Promise;
} else {
  exports.Promise = _dereq_(45);
}
var Promise = exports.Promise;

function toObject(array) {
  return array.reduce(function (obj, item) { 
    obj[item] = true;
    return obj;
  }, {});
}
// List of top level reserved words for doc
var reservedWords = toObject([
  '_id',
  '_rev',
  '_attachments',
  '_deleted',
  '_revisions',
  '_revs_info',
  '_conflicts',
  '_deleted_conflicts',
  '_local_seq',
  '_rev_tree',
  //replication documents
  '_replication_id',
  '_replication_state',
  '_replication_state_time',
  '_replication_state_reason',
  '_replication_stats',
  // Specific to Couchbase Sync Gateway
  '_removed'
]);

// List of reserved words that should end up the document
var dataWords = toObject([
  '_attachments',
  //replication documents
  '_replication_id',
  '_replication_state',
  '_replication_state_time',
  '_replication_state_reason',
  '_replication_stats'
]);

exports.lastIndexOf = function (str, char) {
  for (var i = str.length - 1; i >= 0; i--) {
    if (str.charAt(i) === char) {
      return i;
    }
  }
  return -1;
};

exports.clone = function (obj) {
  return exports.extend(true, {}, obj);
};

// like underscore/lodash _.pick()
exports.pick = function (obj, arr) {
  var res = {};
  for (var i = 0, len = arr.length; i < len; i++) {
    var prop = arr[i];
    res[prop] = obj[prop];
  }
  return res;
};

exports.inherits = _dereq_(41);

// Determine id an ID is valid
//   - invalid IDs begin with an underescore that does not begin '_design' or
//     '_local'
//   - any other string value is a valid id
// Returns the specific error object for each case
exports.invalidIdError = function (id) {
  var err;
  if (!id) {
    err = errors.error(errors.MISSING_ID);
  } else if (typeof id !== 'string') {
    err = errors.error(errors.INVALID_ID);
  } else if (/^_/.test(id) && !(/^_(design|local)/).test(id)) {
    err = errors.error(errors.RESERVED_ID);
  }
  if (err) {
    throw err;
  }
};

function isChromeApp() {
  return (typeof chrome !== "undefined" &&
          typeof chrome.storage !== "undefined" &&
          typeof chrome.storage.local !== "undefined");
}

// Pretty dumb name for a function, just wraps callback calls so we dont
// to if (callback) callback() everywhere
exports.call = exports.getArguments(function (args) {
  if (!args.length) {
    return;
  }
  var fun = args.shift();
  if (typeof fun === 'function') {
    fun.apply(this, args);
  }
});

exports.isLocalId = function (id) {
  return (/^_local/).test(id);
};

// check if a specific revision of a doc has been deleted
//  - metadata: the metadata object from the doc store
//  - rev: (optional) the revision to check. defaults to winning revision
exports.isDeleted = function (metadata, rev) {
  if (!rev) {
    rev = merge.winningRev(metadata);
  }
  var dashIndex = rev.indexOf('-');
  if (dashIndex !== -1) {
    rev = rev.substring(dashIndex + 1);
  }
  var deleted = false;
  merge.traverseRevTree(metadata.rev_tree,
  function (isLeaf, pos, id, acc, opts) {
    if (id === rev) {
      deleted = !!opts.deleted;
    }
  });

  return deleted;
};

exports.revExists = function (metadata, rev) {
  var found = false;
  merge.traverseRevTree(metadata.rev_tree, function (leaf, pos, id) {
    if ((pos + '-' + id) === rev) {
      found = true;
    }
  });
  return found;
};

exports.filterChange = function filterChange(opts) {
  var req = {};
  var hasFilter = opts.filter && typeof opts.filter === 'function';
  req.query = opts.query_params;

  return function filter(change) {
    if (opts.filter && hasFilter && !opts.filter.call(this, change.doc, req)) {
      return false;
    }
    if (!opts.include_docs) {
      delete change.doc;
    } else if (!opts.attachments) {
      for (var att in change.doc._attachments) {
        if (change.doc._attachments.hasOwnProperty(att)) {
          change.doc._attachments[att].stub = true;
        }
      }
    }
    return true;
  };
};

// Preprocess documents, parse their revisions, assign an id and a
// revision for new writes that are missing them, etc
exports.parseDoc = function (doc, newEdits) {

  var nRevNum;
  var newRevId;
  var revInfo;
  var error;
  var opts = {status: 'available'};
  if (doc._deleted) {
    opts.deleted = true;
  }

  function parseRevisionInfo() {
    revInfo = /^(\d+)-(.+)$/.exec(doc._rev);
    if (!revInfo) {
      error = errors.error(errors.INVALID_REV);
      return error;
    }
    return {
      prefix: parseInt(revInfo[1], 10),
      id: revInfo[2]
    };
  }

  if (newEdits) {
    if (!doc._id) {
      doc._id = exports.uuid();
    }
    newRevId = exports.uuid(32, 16).toLowerCase();
    if (doc._rev) {
      revInfo = parseRevisionInfo(doc._rev);
      if (revInfo.error) {
        return revInfo;
      }
      doc._rev_tree = [{
        pos: revInfo.prefix,
        ids: [revInfo.id, {status: 'missing'}, [[newRevId, opts, []]]]
      }];
      nRevNum = revInfo.prefix + 1;
    } else {
      doc._rev_tree = [{
        pos: 1,
        ids : [newRevId, opts, []]
      }];
      nRevNum = 1;
    }
  } else {
    if (doc._revisions) {
      doc._rev_tree = [{
        pos: doc._revisions.start - doc._revisions.ids.length + 1,
        ids: doc._revisions.ids.reduce(function (acc, x) {
          if (acc === null) {
            return [x, opts, []];
          } else {
            return [x, {status: 'missing'}, [acc]];
          }
        }, null)
      }];
      nRevNum = doc._revisions.start;
      newRevId = doc._revisions.ids[0];
    }
    if (!doc._rev_tree) {
      revInfo = parseRevisionInfo(doc._rev);
      if (revInfo.error) {
        return revInfo;
      }
      nRevNum = revInfo.prefix;
      newRevId = revInfo.id;
      doc._rev_tree = [{
        pos: nRevNum,
        ids: [newRevId, opts, []]
      }];
    }
  }

  exports.invalidIdError(doc._id);

  doc._rev = [nRevNum, newRevId].join('-');

  var result = {metadata : {}, data : {}};
  for (var key in doc) {
    if (doc.hasOwnProperty(key)) {
      var specialKey = key[0] === '_';
      if (specialKey && !reservedWords[key]) {
        error = errors.error(errors.DOC_VALIDATION, key);
        error.message = errors.DOC_VALIDATION.message + ': ' + key;
        throw error;
      } else if (specialKey && !dataWords[key]) {
        result.metadata[key.slice(1)] = doc[key];
      } else {
        result.data[key] = doc[key];
      }
    }
  }
  return result;
};

exports.isCordova = function () {
  return (typeof cordova !== "undefined" ||
          typeof PhoneGap !== "undefined" ||
          typeof phonegap !== "undefined");
};

exports.hasLocalStorage = function () {
  if (isChromeApp()) {
    return false;
  }
  try {
    return localStorage;
  } catch (e) {
    return false;
  }
};
exports.Changes = Changes;
exports.inherits(Changes, EventEmitter);
function Changes() {
  if (!(this instanceof Changes)) {
    return new Changes();
  }
  var self = this;
  EventEmitter.call(this);
  this.isChrome = isChromeApp();
  this.listeners = {};
  this.hasLocal = false;
  if (!this.isChrome) {
    this.hasLocal = exports.hasLocalStorage();
  }
  if (this.isChrome) {
    chrome.storage.onChanged.addListener(function (e) {
      // make sure it's event addressed to us
      if (e.db_name != null) {
        //object only has oldValue, newValue members
        self.emit(e.dbName.newValue);
      }
    });
  } else if (this.hasLocal) {
    if (typeof addEventListener !== 'undefined') {
      addEventListener("storage", function (e) {
        self.emit(e.key);
      });
    } else { // old IE
      window.attachEvent("storage", function (e) {
        self.emit(e.key);
      });
    }
  }

}
Changes.prototype.addListener = function (dbName, id, db, opts) {
  if (this.listeners[id]) {
    return;
  }
  var self = this;
  var inprogress = false;
  function eventFunction() {
    if (!self.listeners[id]) {
      return;
    }
    if (inprogress) {
      inprogress = 'waiting';
      return;
    }
    inprogress = true;
    db.changes({
      include_docs: opts.include_docs,
      attachments: opts.attachments,
      conflicts: opts.conflicts,
      continuous: false,
      descending: false,
      filter: opts.filter,
      doc_ids: opts.doc_ids,
      view: opts.view,
      since: opts.since,
      query_params: opts.query_params
    }).on('change', function (c) {
      if (c.seq > opts.since && !opts.cancelled) {
        opts.since = c.seq;
        exports.call(opts.onChange, c);
      }
    }).on('complete', function () {
      if (inprogress === 'waiting') {
        process.nextTick(function () {
          self.notify(dbName);
        });
      }
      inprogress = false;
    }).on('error', function () {
      inprogress = false;
    });
  }
  this.listeners[id] = eventFunction;
  this.on(dbName, eventFunction);
};

Changes.prototype.removeListener = function (dbName, id) {
  if (!(id in this.listeners)) {
    return;
  }
  EventEmitter.prototype.removeListener.call(this, dbName,
    this.listeners[id]);
};


Changes.prototype.notifyLocalWindows = function (dbName) {
  //do a useless change on a storage thing
  //in order to get other windows's listeners to activate
  if (this.isChrome) {
    chrome.storage.local.set({dbName: dbName});
  } else if (this.hasLocal) {
    localStorage[dbName] = (localStorage[dbName] === "a") ? "b" : "a";
  }
};

Changes.prototype.notify = function (dbName) {
  this.emit(dbName);
  this.notifyLocalWindows(dbName);
};

if (typeof window === 'undefined' || typeof window.atob !== 'function') {
  exports.atob = function (str) {
    var base64 = new buffer(str, 'base64');
    // Node.js will just skip the characters it can't encode instead of
    // throwing and exception
    if (base64.toString('base64') !== str) {
      throw ("Cannot base64 encode full string");
    }
    return base64.toString('binary');
  };
} else {
  exports.atob = function (str) {
    return atob(str);
  };
}

if (typeof window === 'undefined' || typeof window.btoa !== 'function') {
  exports.btoa = function (str) {
    return new buffer(str, 'binary').toString('base64');
  };
} else {
  exports.btoa = function (str) {
    return btoa(str);
  };
}

// From http://stackoverflow.com/questions/14967647/ (continues on next line)
// encode-decode-image-with-base64-breaks-image (2013-04-21)
exports.fixBinary = function (bin) {
  if (!process.browser) {
    // don't need to do this in Node
    return bin;
  }

  var length = bin.length;
  var buf = new ArrayBuffer(length);
  var arr = new Uint8Array(buf);
  for (var i = 0; i < length; i++) {
    arr[i] = bin.charCodeAt(i);
  }
  return buf;
};

// shim for browsers that don't support it
exports.readAsBinaryString = function (blob, callback) {
  var reader = new FileReader();
  var hasBinaryString = typeof reader.readAsBinaryString === 'function';
  reader.onloadend = function (e) {
    var result = e.target.result || '';
    if (hasBinaryString) {
      return callback(result);
    }
    callback(exports.arrayBufferToBinaryString(result));
  };
  if (hasBinaryString) {
    reader.readAsBinaryString(blob);
  } else {
    reader.readAsArrayBuffer(blob);
  }
};

exports.once = function (fun) {
  var called = false;
  return exports.getArguments(function (args) {
    if (called) {
      throw new Error('once called  more than once');
    } else {
      called = true;
      fun.apply(this, args);
    }
  });
};

exports.toPromise = function (func) {
  //create the function we will be returning
  return exports.getArguments(function (args) {
    var self = this;
    var tempCB =
      (typeof args[args.length - 1] === 'function') ? args.pop() : false;
    // if the last argument is a function, assume its a callback
    var usedCB;
    if (tempCB) {
      // if it was a callback, create a new callback which calls it,
      // but do so async so we don't trap any errors
      usedCB = function (err, resp) {
        process.nextTick(function () {
          tempCB(err, resp);
        });
      };
    }
    var promise = new Promise(function (fulfill, reject) {
      var resp;
      try {
        var callback = exports.once(function (err, mesg) {
          if (err) {
            reject(err);
          } else {
            fulfill(mesg);
          }
        });
        // create a callback for this invocation
        // apply the function in the orig context
        args.push(callback);
        resp = func.apply(self, args);
        if (resp && typeof resp.then === 'function') {
          fulfill(resp);
        }
      } catch (e) {
        reject(e);
      }
    });
    // if there is a callback, call it back
    if (usedCB) {
      promise.then(function (result) {
        usedCB(null, result);
      }, usedCB);
    }
    promise.cancel = function () {
      return this;
    };
    return promise;
  });
};

exports.adapterFun = function (name, callback) {
  var log = _dereq_(38)('pouchdb:api');

  function logApiCall(self, name, args) {
    if (!log.enabled) {
      return;
    }
    var logArgs = [self._db_name, name];
    for (var i = 0; i < args.length - 1; i++) {
      logArgs.push(args[i]);
    }
    log.apply(null, logArgs);

    // override the callback itself to log the response
    var origCallback = args[args.length - 1];
    args[args.length - 1] = function (err, res) {
      var responseArgs = [self._db_name, name];
      responseArgs = responseArgs.concat(
        err ? ['error', err] : ['success', res]
      );
      log.apply(null, responseArgs);
      origCallback(err, res);
    };
  }


  return exports.toPromise(exports.getArguments(function (args) {
    if (this._closed) {
      return Promise.reject(new Error('database is closed'));
    }
    var self = this;
    logApiCall(self, name, args);
    if (!this.taskqueue.isReady) {
      return new exports.Promise(function (fulfill, reject) {
        self.taskqueue.addTask(function (failed) {
          if (failed) {
            reject(failed);
          } else {
            fulfill(self[name].apply(self, args));
          }
        });
      });
    }
    return callback.apply(this, args);
  }));
};

//Can't find original post, but this is close
//http://stackoverflow.com/questions/6965107/ (continues on next line)
//converting-between-strings-and-arraybuffers
exports.arrayBufferToBinaryString = function (buffer) {
  var binary = "";
  var bytes = new Uint8Array(buffer);
  var length = bytes.byteLength;
  for (var i = 0; i < length; i++) {
    binary += String.fromCharCode(bytes[i]);
  }
  return binary;
};

exports.cancellableFun = function (fun, self, opts) {

  opts = opts ? exports.clone(true, {}, opts) : {};

  var emitter = new EventEmitter();
  var oldComplete = opts.complete || function () { };
  var complete = opts.complete = exports.once(function (err, resp) {
    if (err) {
      oldComplete(err);
    } else {
      emitter.emit('end', resp);
      oldComplete(null, resp);
    }
    emitter.removeAllListeners();
  });
  var oldOnChange = opts.onChange || function () {};
  var lastChange = 0;
  self.on('destroyed', function () {
    emitter.removeAllListeners();
  });
  opts.onChange = function (change) {
    oldOnChange(change);
    if (change.seq <= lastChange) {
      return;
    }
    lastChange = change.seq;
    emitter.emit('change', change);
    if (change.deleted) {
      emitter.emit('delete', change);
    } else if (change.changes.length === 1 &&
      change.changes[0].rev.slice(0, 1) === '1-') {
      emitter.emit('create', change);
    } else {
      emitter.emit('update', change);
    }
  };
  var promise = new Promise(function (fulfill, reject) {
    opts.complete = function (err, res) {
      if (err) {
        reject(err);
      } else {
        fulfill(res);
      }
    };
  });

  promise.then(function (result) {
    complete(null, result);
  }, complete);

  // this needs to be overwridden by caller, dont fire complete until
  // the task is ready
  promise.cancel = function () {
    promise.isCancelled = true;
    if (self.taskqueue.isReady) {
      opts.complete(null, {status: 'cancelled'});
    }
  };

  if (!self.taskqueue.isReady) {
    self.taskqueue.addTask(function () {
      if (promise.isCancelled) {
        opts.complete(null, {status: 'cancelled'});
      } else {
        fun(self, opts, promise);
      }
    });
  } else {
    fun(self, opts, promise);
  }
  promise.on = emitter.on.bind(emitter);
  promise.once = emitter.once.bind(emitter);
  promise.addListener = emitter.addListener.bind(emitter);
  promise.removeListener = emitter.removeListener.bind(emitter);
  promise.removeAllListeners = emitter.removeAllListeners.bind(emitter);
  promise.setMaxListeners = emitter.setMaxListeners.bind(emitter);
  promise.listeners = emitter.listeners.bind(emitter);
  promise.emit = emitter.emit.bind(emitter);
  return promise;
};

exports.MD5 = exports.toPromise(_dereq_(20));

// designed to give info to browser users, who are disturbed
// when they see 404s in the console
exports.explain404 = function (str) {
  if (process.browser && 'console' in global && 'info' in console) {
    console.info('The above 404 is totally normal. ' + str);
  }
};

exports.info = function (str) {
  if (typeof console !== 'undefined' && 'info' in console) {
    console.info(str);
  }
};

exports.parseUri = _dereq_(22);

exports.compare = function (left, right) {
  return left < right ? -1 : left > right ? 1 : 0;
};

exports.updateDoc = function updateDoc(prev, docInfo, results,
                                       i, cb, writeDoc, newEdits) {

  if (exports.revExists(prev, docInfo.metadata.rev)) {
    results[i] = docInfo;
    return cb();
  }

  var previouslyDeleted = exports.isDeleted(prev);
  var deleted = exports.isDeleted(docInfo.metadata);
  var isRoot = /^1-/.test(docInfo.metadata.rev);

  if (previouslyDeleted && !deleted && newEdits && isRoot) {
    var newDoc = docInfo.data;
    newDoc._rev = merge.winningRev(prev);
    newDoc._id = docInfo.metadata.id;
    docInfo = exports.parseDoc(newDoc, newEdits);
  }

  var merged = merge.merge(prev.rev_tree, docInfo.metadata.rev_tree[0], 1000);

  var inConflict = newEdits && (((previouslyDeleted && deleted) ||
    (!previouslyDeleted && merged.conflicts !== 'new_leaf') ||
    (previouslyDeleted && !deleted && merged.conflicts === 'new_branch')));

  if (inConflict) {
    var err = errors.error(errors.REV_CONFLICT);
    results[i] = err;
    return cb();
  }

  var newRev = docInfo.metadata.rev;
  docInfo.metadata.rev_tree = merged.tree;
  if (prev.rev_map) {
    docInfo.metadata.rev_map = prev.rev_map; // used by leveldb
  }

  // recalculate
  var winningRev = merge.winningRev(docInfo.metadata);
  deleted = exports.isDeleted(docInfo.metadata, winningRev);

  var delta = 0;
  if (newEdits || winningRev === newRev) {
    // if newEdits==false and we're pushing existing revisions,
    // then the only thing that matters is whether this revision
    // is the winning one, and thus replaces an old one
    delta = (previouslyDeleted === deleted) ? 0 :
      previouslyDeleted < deleted ? -1 : 1;
  }

  writeDoc(docInfo, winningRev, deleted, cb, true, delta, i);
};

exports.processDocs = function processDocs(docInfos, api, fetchedDocs,
                                           tx, results, writeDoc, opts,
                                           overallCallback) {

  if (!docInfos.length) {
    return;
  }

  function insertDoc(docInfo, resultsIdx, callback) {
    // Cant insert new deleted documents
    var winningRev = merge.winningRev(docInfo.metadata);
    var deleted = exports.isDeleted(docInfo.metadata, winningRev);
    if ('was_delete' in opts && deleted) {
      results[resultsIdx] = errors.error(errors.MISSING_DOC, 'deleted');
      return callback();
    }

    var delta = deleted ? 0 : 1;

    writeDoc(docInfo, winningRev, deleted, callback, false, delta, resultsIdx);
  }

  var newEdits = opts.new_edits;
  var idsToDocs = new exports.Map();

  var docsDone = 0;
  var docsToDo = docInfos.length;

  function checkAllDocsDone() {
    if (++docsDone === docsToDo && overallCallback) {
      overallCallback();
    }
  }

  docInfos.forEach(function (currentDoc, resultsIdx) {

    if (currentDoc._id && exports.isLocalId(currentDoc._id)) {
      api[currentDoc._deleted ? '_removeLocal' : '_putLocal'](
        currentDoc, {ctx: tx}, function (err) {
          if (err) {
            results[resultsIdx] = err;
          } else {
            results[resultsIdx] = {ok: true};
          }
          checkAllDocsDone();
        });
      return;
    }

    var id = currentDoc.metadata.id;
    if (idsToDocs.has(id)) {
      docsToDo--; // duplicate
      idsToDocs.get(id).push([currentDoc, resultsIdx]);
    } else {
      idsToDocs.set(id, [[currentDoc, resultsIdx]]);
    }
  });

  // in the case of new_edits, the user can provide multiple docs
  // with the same id. these need to be processed sequentially
  idsToDocs.forEach(function (docs, id) {
    var numDone = 0;

    function docWritten() {
      if (++numDone < docs.length) {
        nextDoc();
      } else {
        checkAllDocsDone();
      }
    }
    function nextDoc() {
      var value = docs[numDone];
      var currentDoc = value[0];
      var resultsIdx = value[1];

      if (fetchedDocs.has(id)) {
        exports.updateDoc(fetchedDocs.get(id), currentDoc, results,
          resultsIdx, docWritten, writeDoc, newEdits);
      } else {
        insertDoc(currentDoc, resultsIdx, docWritten);
      }
    }
    nextDoc();
  });
};

exports.preprocessAttachments = function preprocessAttachments(
    docInfos, blobType, callback) {

  if (!docInfos.length) {
    return callback();
  }

  var docv = 0;

  function parseBase64(data) {
    try {
      return exports.atob(data);
    } catch (e) {
      var err = errors.error(errors.BAD_ARG,
                             'Attachments need to be base64 encoded');
      return {error: err};
    }
  }

  function preprocessAttachment(att, callback) {
    if (att.stub) {
      return callback();
    }
    if (typeof att.data === 'string') {
      // input is a base64 string

      var asBinary = parseBase64(att.data);
      if (asBinary.error) {
        return callback(asBinary.error);
      }

      att.length = asBinary.length;
      if (blobType === 'blob') {
        att.data = exports.createBlob([exports.fixBinary(asBinary)],
          {type: att.content_type});
      } else if (blobType === 'base64') {
        att.data = exports.btoa(asBinary);
      } else { // binary
        att.data = asBinary;
      }
      exports.MD5(asBinary).then(function (result) {
        att.digest = 'md5-' + result;
        callback();
      });
    } else { // input is a blob
      exports.readAsBinaryString(att.data, function (binary) {
        if (blobType === 'binary') {
          att.data = binary;
        } else if (blobType === 'base64') {
          att.data = exports.btoa(binary);
        }
        exports.MD5(binary).then(function (result) {
          att.digest = 'md5-' + result;
          att.length = binary.length;
          callback();
        });
      });
    }
  }

  var overallErr;

  docInfos.forEach(function (docInfo) {
    var attachments = docInfo.data && docInfo.data._attachments ?
      Object.keys(docInfo.data._attachments) : [];
    var recv = 0;

    if (!attachments.length) {
      return done();
    }

    function processedAttachment(err) {
      overallErr = err;
      recv++;
      if (recv === attachments.length) {
        done();
      }
    }

    for (var key in docInfo.data._attachments) {
      if (docInfo.data._attachments.hasOwnProperty(key)) {
        preprocessAttachment(docInfo.data._attachments[key],
          processedAttachment);
      }
    }
  });

  function done() {
    docv++;
    if (docInfos.length === docv) {
      if (overallErr) {
        callback(overallErr);
      } else {
        callback();
      }
    }
  }
};

// compact a tree by marking its non-leafs as missing,
// and return a list of revs to delete
exports.compactTree = function compactTree(metadata) {
  var revs = [];
  merge.traverseRevTree(metadata.rev_tree, function (isLeaf, pos,
                                                     revHash, ctx, opts) {
    if (opts.status === 'available' && !isLeaf) {
      revs.push(pos + '-' + revHash);
      opts.status = 'missing';
    }
  });
  return revs;
};

var vuvuzela = _dereq_(97);

exports.safeJsonParse = function safeJsonParse(str) {
  try {
    return JSON.parse(str);
  } catch (e) {
    return vuvuzela.parse(str);
  }
};

exports.safeJsonStringify = function safeJsonStringify(json) {
  try {
    return JSON.stringify(json);
  } catch (e) {
    return vuvuzela.stringify(json);
  }
};

}).call(this,_dereq_(37),typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{}],33:[function(_dereq_,module,exports){
module.exports = "3.2.2-prerelease";

},{}],34:[function(_dereq_,module,exports){
'use strict';

module.exports = argsArray;

function argsArray(fun) {
  return function () {
    var len = arguments.length;
    if (len) {
      var args = [];
      var i = -1;
      while (++i < len) {
        args[i] = arguments[i];
      }
      return fun.call(this, args);
    } else {
      return fun.call(this, []);
    }
  };
}
},{}],35:[function(_dereq_,module,exports){

},{}],36:[function(_dereq_,module,exports){
// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

function EventEmitter() {
  this._events = this._events || {};
  this._maxListeners = this._maxListeners || undefined;
}
module.exports = EventEmitter;

// Backwards-compat with node 0.10.x
EventEmitter.EventEmitter = EventEmitter;

EventEmitter.prototype._events = undefined;
EventEmitter.prototype._maxListeners = undefined;

// By default EventEmitters will print a warning if more than 10 listeners are
// added to it. This is a useful default which helps finding memory leaks.
EventEmitter.defaultMaxListeners = 10;

// Obviously not all Emitters should be limited to 10. This function allows
// that to be increased. Set to zero for unlimited.
EventEmitter.prototype.setMaxListeners = function(n) {
  if (!isNumber(n) || n < 0 || isNaN(n))
    throw TypeError('n must be a positive number');
  this._maxListeners = n;
  return this;
};

EventEmitter.prototype.emit = function(type) {
  var er, handler, len, args, i, listeners;

  if (!this._events)
    this._events = {};

  // If there is no 'error' event listener then throw.
  if (type === 'error') {
    if (!this._events.error ||
        (isObject(this._events.error) && !this._events.error.length)) {
      er = arguments[1];
      if (er instanceof Error) {
        throw er; // Unhandled 'error' event
      }
      throw TypeError('Uncaught, unspecified "error" event.');
    }
  }

  handler = this._events[type];

  if (isUndefined(handler))
    return false;

  if (isFunction(handler)) {
    switch (arguments.length) {
      // fast cases
      case 1:
        handler.call(this);
        break;
      case 2:
        handler.call(this, arguments[1]);
        break;
      case 3:
        handler.call(this, arguments[1], arguments[2]);
        break;
      // slower
      default:
        len = arguments.length;
        args = new Array(len - 1);
        for (i = 1; i < len; i++)
          args[i - 1] = arguments[i];
        handler.apply(this, args);
    }
  } else if (isObject(handler)) {
    len = arguments.length;
    args = new Array(len - 1);
    for (i = 1; i < len; i++)
      args[i - 1] = arguments[i];

    listeners = handler.slice();
    len = listeners.length;
    for (i = 0; i < len; i++)
      listeners[i].apply(this, args);
  }

  return true;
};

EventEmitter.prototype.addListener = function(type, listener) {
  var m;

  if (!isFunction(listener))
    throw TypeError('listener must be a function');

  if (!this._events)
    this._events = {};

  // To avoid recursion in the case that type === "newListener"! Before
  // adding it to the listeners, first emit "newListener".
  if (this._events.newListener)
    this.emit('newListener', type,
              isFunction(listener.listener) ?
              listener.listener : listener);

  if (!this._events[type])
    // Optimize the case of one listener. Don't need the extra array object.
    this._events[type] = listener;
  else if (isObject(this._events[type]))
    // If we've already got an array, just append.
    this._events[type].push(listener);
  else
    // Adding the second element, need to change to array.
    this._events[type] = [this._events[type], listener];

  // Check for listener leak
  if (isObject(this._events[type]) && !this._events[type].warned) {
    var m;
    if (!isUndefined(this._maxListeners)) {
      m = this._maxListeners;
    } else {
      m = EventEmitter.defaultMaxListeners;
    }

    if (m && m > 0 && this._events[type].length > m) {
      this._events[type].warned = true;
      console.error('(node) warning: possible EventEmitter memory ' +
                    'leak detected. %d listeners added. ' +
                    'Use emitter.setMaxListeners() to increase limit.',
                    this._events[type].length);
      if (typeof console.trace === 'function') {
        // not supported in IE 10
        console.trace();
      }
    }
  }

  return this;
};

EventEmitter.prototype.on = EventEmitter.prototype.addListener;

EventEmitter.prototype.once = function(type, listener) {
  if (!isFunction(listener))
    throw TypeError('listener must be a function');

  var fired = false;

  function g() {
    this.removeListener(type, g);

    if (!fired) {
      fired = true;
      listener.apply(this, arguments);
    }
  }

  g.listener = listener;
  this.on(type, g);

  return this;
};

// emits a 'removeListener' event iff the listener was removed
EventEmitter.prototype.removeListener = function(type, listener) {
  var list, position, length, i;

  if (!isFunction(listener))
    throw TypeError('listener must be a function');

  if (!this._events || !this._events[type])
    return this;

  list = this._events[type];
  length = list.length;
  position = -1;

  if (list === listener ||
      (isFunction(list.listener) && list.listener === listener)) {
    delete this._events[type];
    if (this._events.removeListener)
      this.emit('removeListener', type, listener);

  } else if (isObject(list)) {
    for (i = length; i-- > 0;) {
      if (list[i] === listener ||
          (list[i].listener && list[i].listener === listener)) {
        position = i;
        break;
      }
    }

    if (position < 0)
      return this;

    if (list.length === 1) {
      list.length = 0;
      delete this._events[type];
    } else {
      list.splice(position, 1);
    }

    if (this._events.removeListener)
      this.emit('removeListener', type, listener);
  }

  return this;
};

EventEmitter.prototype.removeAllListeners = function(type) {
  var key, listeners;

  if (!this._events)
    return this;

  // not listening for removeListener, no need to emit
  if (!this._events.removeListener) {
    if (arguments.length === 0)
      this._events = {};
    else if (this._events[type])
      delete this._events[type];
    return this;
  }

  // emit removeListener for all listeners on all events
  if (arguments.length === 0) {
    for (key in this._events) {
      if (key === 'removeListener') continue;
      this.removeAllListeners(key);
    }
    this.removeAllListeners('removeListener');
    this._events = {};
    return this;
  }

  listeners = this._events[type];

  if (isFunction(listeners)) {
    this.removeListener(type, listeners);
  } else {
    // LIFO order
    while (listeners.length)
      this.removeListener(type, listeners[listeners.length - 1]);
  }
  delete this._events[type];

  return this;
};

EventEmitter.prototype.listeners = function(type) {
  var ret;
  if (!this._events || !this._events[type])
    ret = [];
  else if (isFunction(this._events[type]))
    ret = [this._events[type]];
  else
    ret = this._events[type].slice();
  return ret;
};

EventEmitter.listenerCount = function(emitter, type) {
  var ret;
  if (!emitter._events || !emitter._events[type])
    ret = 0;
  else if (isFunction(emitter._events[type]))
    ret = 1;
  else
    ret = emitter._events[type].length;
  return ret;
};

function isFunction(arg) {
  return typeof arg === 'function';
}

function isNumber(arg) {
  return typeof arg === 'number';
}

function isObject(arg) {
  return typeof arg === 'object' && arg !== null;
}

function isUndefined(arg) {
  return arg === void 0;
}

},{}],37:[function(_dereq_,module,exports){
// shim for using process in browser

var process = module.exports = {};

process.nextTick = (function () {
    var canSetImmediate = typeof window !== 'undefined'
    && window.setImmediate;
    var canMutationObserver = typeof window !== 'undefined'
    && window.MutationObserver;
    var canPost = typeof window !== 'undefined'
    && window.postMessage && window.addEventListener
    ;

    if (canSetImmediate) {
        return function (f) { return window.setImmediate(f) };
    }

    var queue = [];

    if (canMutationObserver) {
        var hiddenDiv = document.createElement("div");
        var observer = new MutationObserver(function () {
            var queueList = queue.slice();
            queue.length = 0;
            queueList.forEach(function (fn) {
                fn();
            });
        });

        observer.observe(hiddenDiv, { attributes: true });

        return function nextTick(fn) {
            if (!queue.length) {
                hiddenDiv.setAttribute('yes', 'no');
            }
            queue.push(fn);
        };
    }

    if (canPost) {
        window.addEventListener('message', function (ev) {
            var source = ev.source;
            if ((source === window || source === null) && ev.data === 'process-tick') {
                ev.stopPropagation();
                if (queue.length > 0) {
                    var fn = queue.shift();
                    fn();
                }
            }
        }, true);

        return function nextTick(fn) {
            queue.push(fn);
            window.postMessage('process-tick', '*');
        };
    }

    return function nextTick(fn) {
        setTimeout(fn, 0);
    };
})();

process.title = 'browser';
process.browser = true;
process.env = {};
process.argv = [];

function noop() {}

process.on = noop;
process.addListener = noop;
process.once = noop;
process.off = noop;
process.removeListener = noop;
process.removeAllListeners = noop;
process.emit = noop;

process.binding = function (name) {
    throw new Error('process.binding is not supported');
};

// TODO(shtylman)
process.cwd = function () { return '/' };
process.chdir = function (dir) {
    throw new Error('process.chdir is not supported');
};

},{}],38:[function(_dereq_,module,exports){

/**
 * This is the web browser implementation of `debug()`.
 *
 * Expose `debug()` as the module.
 */

exports = module.exports = _dereq_(39);
exports.log = log;
exports.formatArgs = formatArgs;
exports.save = save;
exports.load = load;
exports.useColors = useColors;

/**
 * Use chrome.storage.local if we are in an app
 */

var storage;

if (typeof chrome !== 'undefined' && typeof chrome.storage !== 'undefined')
  storage = chrome.storage.local;
else
  storage = window.localStorage;

/**
 * Colors.
 */

exports.colors = [
  'lightseagreen',
  'forestgreen',
  'goldenrod',
  'dodgerblue',
  'darkorchid',
  'crimson'
];

/**
 * Currently only WebKit-based Web Inspectors, Firefox >= v31,
 * and the Firebug extension (any Firefox version) are known
 * to support "%c" CSS customizations.
 *
 * TODO: add a `localStorage` variable to explicitly enable/disable colors
 */

function useColors() {
  // is webkit? http://stackoverflow.com/a/16459606/376773
  return ('WebkitAppearance' in document.documentElement.style) ||
    // is firebug? http://stackoverflow.com/a/398120/376773
    (window.console && (console.firebug || (console.exception && console.table))) ||
    // is firefox >= v31?
    // https://developer.mozilla.org/en-US/docs/Tools/Web_Console#Styling_messages
    (navigator.userAgent.toLowerCase().match(/firefox\/(\d+)/) && parseInt(RegExp.$1, 10) >= 31);
}

/**
 * Map %j to `JSON.stringify()`, since no Web Inspectors do that by default.
 */

exports.formatters.j = function(v) {
  return JSON.stringify(v);
};


/**
 * Colorize log arguments if enabled.
 *
 * @api public
 */

function formatArgs() {
  var args = arguments;
  var useColors = this.useColors;

  args[0] = (useColors ? '%c' : '')
    + this.namespace
    + (useColors ? ' %c' : ' ')
    + args[0]
    + (useColors ? '%c ' : ' ')
    + '+' + exports.humanize(this.diff);

  if (!useColors) return args;

  var c = 'color: ' + this.color;
  args = [args[0], c, 'color: inherit'].concat(Array.prototype.slice.call(args, 1));

  // the final "%c" is somewhat tricky, because there could be other
  // arguments passed either before or after the %c, so we need to
  // figure out the correct index to insert the CSS into
  var index = 0;
  var lastC = 0;
  args[0].replace(/%[a-z%]/g, function(match) {
    if ('%' === match) return;
    index++;
    if ('%c' === match) {
      // we only are interested in the *last* %c
      // (the user may have provided their own)
      lastC = index;
    }
  });

  args.splice(lastC, 0, c);
  return args;
}

/**
 * Invokes `console.log()` when available.
 * No-op when `console.log` is not a "function".
 *
 * @api public
 */

function log() {
  // this hackery is required for IE8/9, where
  // the `console.log` function doesn't have 'apply'
  return 'object' === typeof console
    && console.log
    && Function.prototype.apply.call(console.log, console, arguments);
}

/**
 * Save `namespaces`.
 *
 * @param {String} namespaces
 * @api private
 */

function save(namespaces) {
  try {
    if (null == namespaces) {
      storage.removeItem('debug');
    } else {
      storage.debug = namespaces;
    }
  } catch(e) {}
}

/**
 * Load `namespaces`.
 *
 * @return {String} returns the previously persisted debug modes
 * @api private
 */

function load() {
  var r;
  try {
    r = storage.debug;
  } catch(e) {}
  return r;
}

/**
 * Enable namespaces listed in `localStorage.debug` initially.
 */

exports.enable(load());

},{}],39:[function(_dereq_,module,exports){

/**
 * This is the common logic for both the Node.js and web browser
 * implementations of `debug()`.
 *
 * Expose `debug()` as the module.
 */

exports = module.exports = debug;
exports.coerce = coerce;
exports.disable = disable;
exports.enable = enable;
exports.enabled = enabled;
exports.humanize = _dereq_(40);

/**
 * The currently active debug mode names, and names to skip.
 */

exports.names = [];
exports.skips = [];

/**
 * Map of special "%n" handling functions, for the debug "format" argument.
 *
 * Valid key names are a single, lowercased letter, i.e. "n".
 */

exports.formatters = {};

/**
 * Previously assigned color.
 */

var prevColor = 0;

/**
 * Previous log timestamp.
 */

var prevTime;

/**
 * Select a color.
 *
 * @return {Number}
 * @api private
 */

function selectColor() {
  return exports.colors[prevColor++ % exports.colors.length];
}

/**
 * Create a debugger with the given `namespace`.
 *
 * @param {String} namespace
 * @return {Function}
 * @api public
 */

function debug(namespace) {

  // define the `disabled` version
  function disabled() {
  }
  disabled.enabled = false;

  // define the `enabled` version
  function enabled() {

    var self = enabled;

    // set `diff` timestamp
    var curr = +new Date();
    var ms = curr - (prevTime || curr);
    self.diff = ms;
    self.prev = prevTime;
    self.curr = curr;
    prevTime = curr;

    // add the `color` if not set
    if (null == self.useColors) self.useColors = exports.useColors();
    if (null == self.color && self.useColors) self.color = selectColor();

    var args = Array.prototype.slice.call(arguments);

    args[0] = exports.coerce(args[0]);

    if ('string' !== typeof args[0]) {
      // anything else let's inspect with %o
      args = ['%o'].concat(args);
    }

    // apply any `formatters` transformations
    var index = 0;
    args[0] = args[0].replace(/%([a-z%])/g, function(match, format) {
      // if we encounter an escaped % then don't increase the array index
      if (match === '%') return match;
      index++;
      var formatter = exports.formatters[format];
      if ('function' === typeof formatter) {
        var val = args[index];
        match = formatter.call(self, val);

        // now we need to remove `args[index]` since it's inlined in the `format`
        args.splice(index, 1);
        index--;
      }
      return match;
    });

    if ('function' === typeof exports.formatArgs) {
      args = exports.formatArgs.apply(self, args);
    }
    var logFn = enabled.log || exports.log || console.log.bind(console);
    logFn.apply(self, args);
  }
  enabled.enabled = true;

  var fn = exports.enabled(namespace) ? enabled : disabled;

  fn.namespace = namespace;

  return fn;
}

/**
 * Enables a debug mode by namespaces. This can include modes
 * separated by a colon and wildcards.
 *
 * @param {String} namespaces
 * @api public
 */

function enable(namespaces) {
  exports.save(namespaces);

  var split = (namespaces || '').split(/[\s,]+/);
  var len = split.length;

  for (var i = 0; i < len; i++) {
    if (!split[i]) continue; // ignore empty strings
    namespaces = split[i].replace(/\*/g, '.*?');
    if (namespaces[0] === '-') {
      exports.skips.push(new RegExp('^' + namespaces.substr(1) + '$'));
    } else {
      exports.names.push(new RegExp('^' + namespaces + '$'));
    }
  }
}

/**
 * Disable debug output.
 *
 * @api public
 */

function disable() {
  exports.enable('');
}

/**
 * Returns true if the given mode name is enabled, false otherwise.
 *
 * @param {String} name
 * @return {Boolean}
 * @api public
 */

function enabled(name) {
  var i, len;
  for (i = 0, len = exports.skips.length; i < len; i++) {
    if (exports.skips[i].test(name)) {
      return false;
    }
  }
  for (i = 0, len = exports.names.length; i < len; i++) {
    if (exports.names[i].test(name)) {
      return true;
    }
  }
  return false;
}

/**
 * Coerce `val`.
 *
 * @param {Mixed} val
 * @return {Mixed}
 * @api private
 */

function coerce(val) {
  if (val instanceof Error) return val.stack || val.message;
  return val;
}

},{}],40:[function(_dereq_,module,exports){
/**
 * Helpers.
 */

var s = 1000;
var m = s * 60;
var h = m * 60;
var d = h * 24;
var y = d * 365.25;

/**
 * Parse or format the given `val`.
 *
 * Options:
 *
 *  - `long` verbose formatting [false]
 *
 * @param {String|Number} val
 * @param {Object} options
 * @return {String|Number}
 * @api public
 */

module.exports = function(val, options){
  options = options || {};
  if ('string' == typeof val) return parse(val);
  return options.long
    ? long(val)
    : short(val);
};

/**
 * Parse the given `str` and return milliseconds.
 *
 * @param {String} str
 * @return {Number}
 * @api private
 */

function parse(str) {
  var match = /^((?:\d+)?\.?\d+) *(ms|seconds?|s|minutes?|m|hours?|h|days?|d|years?|y)?$/i.exec(str);
  if (!match) return;
  var n = parseFloat(match[1]);
  var type = (match[2] || 'ms').toLowerCase();
  switch (type) {
    case 'years':
    case 'year':
    case 'y':
      return n * y;
    case 'days':
    case 'day':
    case 'd':
      return n * d;
    case 'hours':
    case 'hour':
    case 'h':
      return n * h;
    case 'minutes':
    case 'minute':
    case 'm':
      return n * m;
    case 'seconds':
    case 'second':
    case 's':
      return n * s;
    case 'ms':
      return n;
  }
}

/**
 * Short format for `ms`.
 *
 * @param {Number} ms
 * @return {String}
 * @api private
 */

function short(ms) {
  if (ms >= d) return Math.round(ms / d) + 'd';
  if (ms >= h) return Math.round(ms / h) + 'h';
  if (ms >= m) return Math.round(ms / m) + 'm';
  if (ms >= s) return Math.round(ms / s) + 's';
  return ms + 'ms';
}

/**
 * Long format for `ms`.
 *
 * @param {Number} ms
 * @return {String}
 * @api private
 */

function long(ms) {
  return plural(ms, d, 'day')
    || plural(ms, h, 'hour')
    || plural(ms, m, 'minute')
    || plural(ms, s, 'second')
    || ms + ' ms';
}

/**
 * Pluralization helper.
 */

function plural(ms, n, name) {
  if (ms < n) return;
  if (ms < n * 1.5) return Math.floor(ms / n) + ' ' + name;
  return Math.ceil(ms / n) + ' ' + name + 's';
}

},{}],41:[function(_dereq_,module,exports){
if (typeof Object.create === 'function') {
  // implementation from standard node.js 'util' module
  module.exports = function inherits(ctor, superCtor) {
    ctor.super_ = superCtor
    ctor.prototype = Object.create(superCtor.prototype, {
      constructor: {
        value: ctor,
        enumerable: false,
        writable: true,
        configurable: true
      }
    });
  };
} else {
  // old school shim for old browsers
  module.exports = function inherits(ctor, superCtor) {
    ctor.super_ = superCtor
    var TempCtor = function () {}
    TempCtor.prototype = superCtor.prototype
    ctor.prototype = new TempCtor()
    ctor.prototype.constructor = ctor
  }
}

},{}],42:[function(_dereq_,module,exports){
'use strict';

module.exports = INTERNAL;

function INTERNAL() {}
},{}],43:[function(_dereq_,module,exports){
'use strict';
var Promise = _dereq_(46);
var reject = _dereq_(49);
var resolve = _dereq_(50);
var INTERNAL = _dereq_(42);
var handlers = _dereq_(44);
module.exports = all;
function all(iterable) {
  if (Object.prototype.toString.call(iterable) !== '[object Array]') {
    return reject(new TypeError('must be an array'));
  }

  var len = iterable.length;
  var called = false;
  if (!len) {
    return resolve([]);
  }

  var values = new Array(len);
  var resolved = 0;
  var i = -1;
  var promise = new Promise(INTERNAL);
  
  while (++i < len) {
    allResolver(iterable[i], i);
  }
  return promise;
  function allResolver(value, i) {
    resolve(value).then(resolveFromAll, function (error) {
      if (!called) {
        called = true;
        handlers.reject(promise, error);
      }
    });
    function resolveFromAll(outValue) {
      values[i] = outValue;
      if (++resolved === len & !called) {
        called = true;
        handlers.resolve(promise, values);
      }
    }
  }
}
},{}],44:[function(_dereq_,module,exports){
'use strict';
var tryCatch = _dereq_(53);
var resolveThenable = _dereq_(51);
var states = _dereq_(52);

exports.resolve = function (self, value) {
  var result = tryCatch(getThen, value);
  if (result.status === 'error') {
    return exports.reject(self, result.value);
  }
  var thenable = result.value;

  if (thenable) {
    resolveThenable.safely(self, thenable);
  } else {
    self.state = states.FULFILLED;
    self.outcome = value;
    var i = -1;
    var len = self.queue.length;
    while (++i < len) {
      self.queue[i].callFulfilled(value);
    }
  }
  return self;
};
exports.reject = function (self, error) {
  self.state = states.REJECTED;
  self.outcome = error;
  var i = -1;
  var len = self.queue.length;
  while (++i < len) {
    self.queue[i].callRejected(error);
  }
  return self;
};

function getThen(obj) {
  // Make sure we only access the accessor once as required by the spec
  var then = obj && obj.then;
  if (obj && typeof obj === 'object' && typeof then === 'function') {
    return function appyThen() {
      then.apply(obj, arguments);
    };
  }
}
},{}],45:[function(_dereq_,module,exports){
module.exports = exports = _dereq_(46);

exports.resolve = _dereq_(50);
exports.reject = _dereq_(49);
exports.all = _dereq_(43);
exports.race = _dereq_(48);
},{}],46:[function(_dereq_,module,exports){
'use strict';

var unwrap = _dereq_(54);
var INTERNAL = _dereq_(42);
var resolveThenable = _dereq_(51);
var states = _dereq_(52);
var QueueItem = _dereq_(47);

module.exports = Promise;
function Promise(resolver) {
  if (!(this instanceof Promise)) {
    return new Promise(resolver);
  }
  if (typeof resolver !== 'function') {
    throw new TypeError('resolver must be a function');
  }
  this.state = states.PENDING;
  this.queue = [];
  this.outcome = void 0;
  if (resolver !== INTERNAL) {
    resolveThenable.safely(this, resolver);
  }
}

Promise.prototype['catch'] = function (onRejected) {
  return this.then(null, onRejected);
};
Promise.prototype.then = function (onFulfilled, onRejected) {
  if (typeof onFulfilled !== 'function' && this.state === states.FULFILLED ||
    typeof onRejected !== 'function' && this.state === states.REJECTED) {
    return this;
  }
  var promise = new Promise(INTERNAL);

  
  if (this.state !== states.PENDING) {
    var resolver = this.state === states.FULFILLED ? onFulfilled: onRejected;
    unwrap(promise, resolver, this.outcome);
  } else {
    this.queue.push(new QueueItem(promise, onFulfilled, onRejected));
  }

  return promise;
};

},{}],47:[function(_dereq_,module,exports){
'use strict';
var handlers = _dereq_(44);
var unwrap = _dereq_(54);

module.exports = QueueItem;
function QueueItem(promise, onFulfilled, onRejected) {
  this.promise = promise;
  if (typeof onFulfilled === 'function') {
    this.onFulfilled = onFulfilled;
    this.callFulfilled = this.otherCallFulfilled;
  }
  if (typeof onRejected === 'function') {
    this.onRejected = onRejected;
    this.callRejected = this.otherCallRejected;
  }
}
QueueItem.prototype.callFulfilled = function (value) {
  handlers.resolve(this.promise, value);
};
QueueItem.prototype.otherCallFulfilled = function (value) {
  unwrap(this.promise, this.onFulfilled, value);
};
QueueItem.prototype.callRejected = function (value) {
  handlers.reject(this.promise, value);
};
QueueItem.prototype.otherCallRejected = function (value) {
  unwrap(this.promise, this.onRejected, value);
};
},{}],48:[function(_dereq_,module,exports){
'use strict';
var Promise = _dereq_(46);
var reject = _dereq_(49);
var resolve = _dereq_(50);
var INTERNAL = _dereq_(42);
var handlers = _dereq_(44);
module.exports = race;
function race(iterable) {
  if (Object.prototype.toString.call(iterable) !== '[object Array]') {
    return reject(new TypeError('must be an array'));
  }

  var len = iterable.length;
  var called = false;
  if (!len) {
    return resolve([]);
  }

  var resolved = 0;
  var i = -1;
  var promise = new Promise(INTERNAL);
  
  while (++i < len) {
    resolver(iterable[i]);
  }
  return promise;
  function resolver(value) {
    resolve(value).then(function (response) {
      if (!called) {
        called = true;
        handlers.resolve(promise, response);
      }
    }, function (error) {
      if (!called) {
        called = true;
        handlers.reject(promise, error);
      }
    });
  }
}
},{}],49:[function(_dereq_,module,exports){
'use strict';

var Promise = _dereq_(46);
var INTERNAL = _dereq_(42);
var handlers = _dereq_(44);
module.exports = reject;

function reject(reason) {
	var promise = new Promise(INTERNAL);
	return handlers.reject(promise, reason);
}
},{}],50:[function(_dereq_,module,exports){
'use strict';

var Promise = _dereq_(46);
var INTERNAL = _dereq_(42);
var handlers = _dereq_(44);
module.exports = resolve;

var FALSE = handlers.resolve(new Promise(INTERNAL), false);
var NULL = handlers.resolve(new Promise(INTERNAL), null);
var UNDEFINED = handlers.resolve(new Promise(INTERNAL), void 0);
var ZERO = handlers.resolve(new Promise(INTERNAL), 0);
var EMPTYSTRING = handlers.resolve(new Promise(INTERNAL), '');

function resolve(value) {
  if (value) {
    if (value instanceof Promise) {
      return value;
    }
    return handlers.resolve(new Promise(INTERNAL), value);
  }
  var valueType = typeof value;
  switch (valueType) {
    case 'boolean':
      return FALSE;
    case 'undefined':
      return UNDEFINED;
    case 'object':
      return NULL;
    case 'number':
      return ZERO;
    case 'string':
      return EMPTYSTRING;
  }
}
},{}],51:[function(_dereq_,module,exports){
'use strict';
var handlers = _dereq_(44);
var tryCatch = _dereq_(53);
function safelyResolveThenable(self, thenable) {
  // Either fulfill, reject or reject with error
  var called = false;
  function onError(value) {
    if (called) {
      return;
    }
    called = true;
    handlers.reject(self, value);
  }

  function onSuccess(value) {
    if (called) {
      return;
    }
    called = true;
    handlers.resolve(self, value);
  }

  function tryToUnwrap() {
    thenable(onSuccess, onError);
  }
  
  var result = tryCatch(tryToUnwrap);
  if (result.status === 'error') {
    onError(result.value);
  }
}
exports.safely = safelyResolveThenable;
},{}],52:[function(_dereq_,module,exports){
// Lazy man's symbols for states

exports.REJECTED = ['REJECTED'];
exports.FULFILLED = ['FULFILLED'];
exports.PENDING = ['PENDING'];
},{}],53:[function(_dereq_,module,exports){
'use strict';

module.exports = tryCatch;

function tryCatch(func, value) {
  var out = {};
  try {
    out.value = func(value);
    out.status = 'success';
  } catch (e) {
    out.status = 'error';
    out.value = e;
  }
  return out;
}
},{}],54:[function(_dereq_,module,exports){
'use strict';

var immediate = _dereq_(55);
var handlers = _dereq_(44);
module.exports = unwrap;

function unwrap(promise, func, value) {
  immediate(function () {
    var returnValue;
    try {
      returnValue = func(value);
    } catch (e) {
      return handlers.reject(promise, e);
    }
    if (returnValue === promise) {
      handlers.reject(promise, new TypeError('Cannot resolve promise with itself'));
    } else {
      handlers.resolve(promise, returnValue);
    }
  });
}
},{}],55:[function(_dereq_,module,exports){
'use strict';
var types = [
  _dereq_(35),
  _dereq_(57),
  _dereq_(56),
  _dereq_(58),
  _dereq_(59)
];
var draining;
var queue = [];
//named nextTick for less confusing stack traces
function nextTick() {
  draining = true;
  var i, oldQueue;
  var len = queue.length;
  while (len) {
    oldQueue = queue;
    queue = [];
    i = -1;
    while (++i < len) {
      oldQueue[i]();
    }
    len = queue.length;
  }
  draining = false;
}
var scheduleDrain;
var i = -1;
var len = types.length;
while (++ i < len) {
  if (types[i] && types[i].test && types[i].test()) {
    scheduleDrain = types[i].install(nextTick);
    break;
  }
}
module.exports = immediate;
function immediate(task) {
  if (queue.push(task) === 1 && !draining) {
    scheduleDrain();
  }
}
},{}],56:[function(_dereq_,module,exports){
(function (global){
'use strict';

exports.test = function () {
  if (global.setImmediate) {
    // we can only get here in IE10
    // which doesn't handel postMessage well
    return false;
  }
  return typeof global.MessageChannel !== 'undefined';
};

exports.install = function (func) {
  var channel = new global.MessageChannel();
  channel.port1.onmessage = func;
  return function () {
    channel.port2.postMessage(0);
  };
};
}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{}],57:[function(_dereq_,module,exports){
(function (global){
'use strict';
//based off rsvp https://github.com/tildeio/rsvp.js
//license https://github.com/tildeio/rsvp.js/blob/master/LICENSE
//https://github.com/tildeio/rsvp.js/blob/master/lib/rsvp/asap.js

var Mutation = global.MutationObserver || global.WebKitMutationObserver;

exports.test = function () {
  return Mutation;
};

exports.install = function (handle) {
  var called = 0;
  var observer = new Mutation(handle);
  var element = global.document.createTextNode('');
  observer.observe(element, {
    characterData: true
  });
  return function () {
    element.data = (called = ++called % 2);
  };
};
}).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
},{}],58:[function(_dereq_,module,exports){
(function (global){
'use strict';

exports.test = function () {
  return 'document' in global && 'onreadystatechange' in global.document.createElement('script');
};

exports.install = function (handle) {
  return function () {

    // Create a