<?php
namespace Common\Model;

/**
 * 生成多层树状下拉选框的工具模型
 */
class TreeModel {
	/**
 * 把返回的数据集转换成Tree
 * @access public
 * @param array $list 要转换的数据集
 * @param string $pid parent标记字段
 * @param string $level level标记字段
 * @return array
 */
	public function toTree($list=null, $pk='id',$pid = 'pid',$child = '_child'){
		if(null === $list) {
 // 默认直接取查询返回的结果集合
			$list = &$this->dataList;
		}
 // 创建Tree
		$tree = array();
		if(is_array($list)) {
 // 创建基于主键的数组引用
			$refer = array();

			foreach ($list as $key => $data) {
				$_key = is_object($data)?$data->$pk:$data[$pk];
				$refer[$_key] =& $list[$key];
			}
			foreach ($list as $key => $data) {
 // 判断是否存在parent
				$parentId = is_object($data)?$data->$pid:$data[$pid];
				$is_exist_pid = false;
				foreach($refer as $k=>$v){
					if($parentId==$k){
						$is_exist_pid = true;
						break;
					}
				}
				if ($is_exist_pid) {
					if (isset($refer[$parentId])) {
						$parent =& $refer[$parentId];
						$parent[$child][] =& $list[$key];
					}
				} else {
					$tree[] =& $list[$key];
				}
			}
		}
		return $tree;
	}

	/**
	 * 将格式数组转换为树
	 *
	 * @param array $list
	 * @param integer $level 进行递归时传递用的参数
	 */
	private $formatTree; //用于树型数组完成递归格式的全局变量
	private function _toFormatTree($list,$level=0,$title = 'title') {
		foreach($list as $key=>$val){
			$tmp_str=str_repeat("&nbsp;",$level*2);
			$tmp_str.="└";

			$val['level'] = $level;
			$val['title_show'] =$level==0?$val[$title]."&nbsp;":$tmp_str.$val[$title]."&nbsp;";
				// $val['title_show'] = $val['id'].'|'.$level.'级|'.$val['title_show'];
			if(!array_key_exists('_child',$val)){
				array_push($this->formatTree,$val);
			}else{
				$tmp_ary = $val['_child'];
				unset($val['_child']);
				array_push($this->formatTree,$val);
				 $this->_toFormatTree($tmp_ary,$level+1,$title); //进行下一层递归
				}
			}
			return;
		}

		public function toFormatTree($list,$title = 'title',$pk='id',$pid = 'pid',$root = 0){
			$list = list_to_tree($list,$pk,$pid,'_child',$root);
			$this->formatTree = array();
			$this->_toFormatTree($list,0,$title);
			return $this->formatTree;
		}
	}
	?>