<?php 	
class ParentChild {	

   /* 
	* Class Name : ParentChild
	* Purpose : This class is made for populating a tree/list of items based on the parent child relationships among them with unlimited level of hierarchy . 
	* Author : Mrinal Nandi <nandi.mrinal2005@gmail.com> - mrinal.0fees.net 
	* Copyright (c) Mrinal Nandi 
	* 
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this script/software , to deal in the Script/Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Script/Software, and to permit persons to whom the Script/Software is
	* furnished to do so, subject to the following conditions:
	* 
	* The above copyright notice, the information about the author and this permission notice shall be included in
	* all copies or substantial portions of the Script/Software.
	* 
	* THE SCRIPT/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 SCRIPT/SOFTWARE OR THE USE OR OTHER DEALINGS IN
	* THE SCRIPT/SOFTWARE.
	* 
	*/
	
	//properties which hold database and table related information  : start 	
	var $db_host;
	var $db_user;
	var $db_pass;
	var $db_database;
	var $db_table; 
	
	
	var $item_identifier_field_name;  //may be the primary key of the table : as decided by the db designer 
	var $parent_identifier_field_name; //the fileld name in the table which holds the value of the item_identifier_field_name any item's parent	: as decided by the db designer
	var $item_list_field_name; //field name in the table whose value will be shown in the list or tree (like name or any id etc.) : as choosen by the programmer 
	
	var $extra_condition="";  //if any extra condition should be added with the query : as desided by the programmer 
	var $order_by_phrase="";  //if any order by phrase should be added with the query : as desided by the programmer 
	//properties which hold database and table related information  : end
	
	
	
	var $level_identifier = "";  //no. of level of any item as per the generated tree : it will appear number of level times before the item in the list/tree
	var $item_pointer = ""; 
	
	
	
	var $all_childs = array(); //contains the entire tree or list starting from a given root element
	
	var $item_path = array(); //contains the total path of a given element/node(the list of elements starting from the top level root node to the given element/node)
	
	public function getAllChilds($Parent_ID, $level_identifier="", $start=true) { // get all the childs of all the levels under a parent as a tree		
		$immediate_childs=$this->getImmediateChilds($Parent_ID,  $this->extra_condition, $this->order_by_phrase);
		if(count($immediate_childs)) {
			foreach($immediate_childs as $chld) {
				$chld[$this->item_list_field_name]=$level_identifier.$this->item_pointer.$chld[$this->item_list_field_name];
				array_push($this->all_childs,$chld);
				$this->getAllChilds($chld[$this->item_identifier_field_name], ($level_identifier.$this->level_identifier), false);
			}
		}
		if($start) {
			return $this->all_childs; 
		}
	} 
	
	private function getImmediateChilds($parent_identifier_field_value, $extra_condition="", $order_by_phrase="") { 
		// get only the direct/immediate childs under a parent 
		global $db;
		 $sql="SELECT * FROM `".$this->db_table."` WHERE  ifnull(".$this->parent_identifier_field_name.",'-99')='".$parent_identifier_field_value."' ".$extra_condition." ".$order_by_phrase;
		$res = $db->query($sql);
		$childs=array();
		foreach($res->fetchAll() as $val) {
			array_push($childs,$val);
		}
		return $childs;	
	}
	
	public function getItemPath($item_id,$start=true){ //returns the total path of a given item/node(the list of elements starting from the top level root node to the given item/node)
		global $db;
		if($item_id != 0) {
			 $sql="SELECT * FROM `".$this->db_table."` WHERE `".$this->item_identifier_field_name."`='".$item_id."' ";
			$res = $db->query($sql);
			$itemdata = $res->fetchAll()[0];
			array_push($this->item_path,$itemdata); 
		
			if($itemdata[$this->parent_identifier_field_name]!=0) {
				$this->item_path=$this->getItemPath($itemdata[$this->parent_identifier_field_name],false);
			} 
			if ($start) {
				$this->item_path=array_reverse($this->item_path);
			}
		}
		return $this->item_path;
		
	}
	
} 
?>