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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package io.milton.http.values;

import io.milton.http.XmlWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import javax.xml.namespace.QName;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Default list of value writers. These are used to format strongly types
 * property values (eg Date, Boolean, Locks) into the appropriate XML
 *
 * They also parse string values in PROPPATCH requests into the strongly typed
 * values.
 *
 * @author brad
 */
public class ValueWriters {

	private static final Logger log = LoggerFactory.getLogger(ValueWriters.class);
	private final List writers;

	/**
	 * Allows the set of value writers to be injected
	 *
	 * @param valueWriters
	 */
	public ValueWriters(List valueWriters) {
		this.writers = valueWriters;
	}

	/**
	 * Initialised the default set of writers
	 *
	 */
	public ValueWriters() {
		writers = new ArrayList<>();

		// BM: Note that windows explorer is picky about its date format. This
		// property writer supports it explicitly
		writers.add(new ModifiedDateValueWriter());
		writers.add(new DateValueWriter());
		writers.add(new ResourceTypeValueWriter());
		writers.add(new BooleanValueWriter());
		writers.add(new CDataValueWriter());
		writers.add(new UUIDValueWriter());
		writers.add(new HrefListValueWriter());
		writers.add(new WrappedHrefWriter());
		writers.add(new SupportedReportSetWriter());
		writers.add(new AddressDataTypeListValueWriter());
		writers.add(new PriviledgeListValueWriter());
		// ToStringValueWriter is the default value writer and applied when no 
		// other writer is available.
		writers.add(new ToStringValueWriter());
	}

	/**
	 * Find the first value writer which supports the given property and use it
	 * to output the XML.
	 *
	 * @param writer
	 * @param qname
	 * @param prefix
	 * @param vat
	 * @param href
	 * @param nsPrefixes
	 */
	public void writeValue(XmlWriter writer, QName qname, String prefix, ValueAndType vat, String href, Map nsPrefixes) {
		for (ValueWriter vw : writers) {
			if (log.isTraceEnabled()) {
				if (vat.getValue() != null) {
					if (vat.getValue().getClass() != vat.getType()) {
						throw new RuntimeException("Inconsistent type information: " + vat.getValue().getClass() + " != " + vat.getType());
					}
				}
			}
			if (vw.supports(qname.getNamespaceURI(), qname.getLocalPart(), vat.getType())) {
				vw.writeValue(writer, qname.getNamespaceURI(), prefix, qname.getLocalPart(), vat.getValue(), href, nsPrefixes);
				break;
			}
		}
	}

	public List getValueWriters() {
		return writers;
	}

	/**
	 * Find the first ValueWriter which supports the given property and use it
	 * to parse the value
	 *
	 * @param qname
	 * @param valueType
	 * @param value
	 * @return
	 */
	public Object parse(QName qname, Class valueType, String value) {
		for (ValueWriter vw : writers) {
			if (vw.supports(qname.getNamespaceURI(), qname.getLocalPart(), valueType)) {
				log.trace("parse: Found supporting value writer {} ", vw);
				return vw.parse(qname.getNamespaceURI(), qname.getLocalPart(), value);
			}
		}
		log.warn("parse: No value writer supports: qname: " + qname + " type:" + valueType + " value:" + value);
		return null;
	}
}