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package cn.dreampie.common.util.tree;

import com.google.common.collect.Lists;

import java.util.Collections;
import java.util.Comparator;
import java.util.List;

/**
 * Created by wangrenhui on 14-4-12.
 */
public class TreeUtils {

  public static List toTree(List params) {
    List nodes = null;
    if (params.size() > 0) {
      //优先级排序
      Collections.sort(params, new Comparator() {
        @Override
        public int compare(TreeNode rp1, TreeNode rp2) {
          return Long.compare(rp1.getParentId(), rp2.getParentId());
        }
      });
      nodes = toTree(params, ((TreeNode) params.get(0)).getParentId());
    }
    return nodes;
  }

  public static List toTreeLevel(List params, int level) {
    List nodes = null;
    if (params.size() > 0) {
      //优先级排序
      Collections.sort(params, new Comparator() {
        @Override
        public int compare(TreeNode rp1, TreeNode rp2) {
          return Long.compare(rp1.getParentId(), rp2.getParentId());
        }
      });
      nodes = toTreeLevel(params, ((TreeNode) params.get(0)).getParentId(), level);
    }
    return nodes;
  }

  /**
   * 无限级树形结构
   *
   * @param params params
   * @param pid    pid
   * @return list
   */
  public static List toTree(List params, long pid) {
    List nodes = Lists.newArrayList();

    if (params != null && params.size() > 0) {

      TreeNode node = null;
      for (int i = 0; i < params.size(); i++) {
        node = (TreeNode) params.get(i);
        if (node.getParentId() == pid) {
          nodes.add(node);
          params.remove(i);
          node.setChildren(toTree(params, node.getId()));
          i--;
        }
      }
    }
    return nodes;
  }

  /**
   * 两级树形数据
   *
   * @param params params
   * @param pid    pid
   * @param level  level
   * @return list
   */
  public static List toTreeLevel(List params, long pid, int level) {
    List nodes = Lists.newArrayList();

    if (params != null && params.size() > 0) {
      TreeNode node = null;//当前节点
      for (int i = 0; i < params.size(); i++) {
        node = (TreeNode) params.get(i);
        if (node.getParentId() == pid) {
          nodes.add(node);
          params.remove(i);
          if (level > 1) {
//                        System.out.println(node.getId() + ":" + level);
            node.setChildren(toTreeLevel(params, node.getId(), --level));
          } else {
//                        System.out.println(node.getId() + ":" + level + ":" + nodes.size());
            nodes.addAll(toTreeLevel(params, node.getId(), --level));
          }
          level++;
          i--;
        }
      }
    }
    return nodes;
  }
//
//    public static void main(String[] args) {
//        List params = Lists.newArrayList();
//        Channel channel = new Channel();
//        channel.setId(1);
//        channel.setParentId(0);
//        params.add(channel);
//        channel = new Channel();
//        channel.setId(2);
//        channel.setParentId(1);
//        params.add(channel);
//        channel = new Channel();
//        channel.setId(3);
//        channel.setParentId(2);
//        params.add(channel);
//        channel = new Channel();
//        channel.setId(4);
//        channel.setParentId(0);
//        params.add(channel);
//        channel = new Channel();
//        channel.setId(5);
//        channel.setParentId(1);
//        params.add(channel);
//        List res = new TreeUtils().toTree(params);
//        System.out.print(StringUtils.join(res, ","));
//    }
}