<?php
class xmlParser {
	/**
	 *@author: Michael Bianco, http://mabwebdesign.com/
	 *@package: xmlParser class											
	 *@version: 1.0; Requires PHP 4.3.6 (might work with older versions, but hasn't been tested)
	 *@description: this class is suppossed to be extended. The class extending this class must have these methods:
	 *	@function: doneParse()
	 *	@description: This function is called when all the parsing is complete
	 *
	 *	@funtion: startElementHandler(String $tag_name, Array $atrribs)
	 *	@description: This function is called when the parser hits a starting tag
	 *
	 *	@function: endElementHandler(String $tag_name)
	 *	@description: This function is called when the parser hits a closing tag
	 *
	 *	@function: dataHandler($data)
	 *	@description: This function is called when the parser hits character data
	 *
	 *@decription: The class has the following class vars:
	 *	@var: $this->curr_tag
	 *	@description: a string representation of the current tag. It is ALWAYS in upper case
	 *
	 *	@var: $this->repeat
	 *	@description: look below
	 *
	 ****************************************************
	 *@extra-info: the php xml parser handler specail chars that are encoded with entites as a seperate data cell.
	 *We get around this by using a counter to determine if the xml parser is looking at the same cell. This parser automatically
	 *Keeps track of this with the $this->repeat var. $this->repeat == true when the cell is repeated, false when it isn't.
	 **/
	 	
	var $xml_data = 0; //the xml data
	var $tag_pos = -1; //intertal tagPos counters
	var $curr_tag; //defines the current tag that the parser is parsing
	var $ent_c = 0; //the current entitie counter
	var $prev_ent_c = 0; //the previous entity counter
	var $repeat; //a boolean determining if the parser is looking at the same Node (which means it is parsering entities)
	
   function xmlParser() {
       $this->parser = xml_parser_create();
   }
   
   function _openFile($file) {   		
   		$this->_parsePrepare(); //sets all the xml parsing vars
   		if($this->xml_data = file_get_contents($file)) {
   			return true;
   		} else {
   			exit('Error reading file');
   		}
   }
   
   function _parsePrepare() {
       $this->stack = array(); // this keeps track of what tag level you're at
       xml_set_object($this->parser, $this);
       xml_set_element_handler($this->parser, "_startElementHandler", "_endElementHandler");
       xml_set_character_data_handler($this->parser, "_dataHandler");
   }

   /**
    *@param: $file, defines the URL tot he file to be parsed
    *@description: parsers the XML from the file specifies
    **/
   function parseXML($file) {
   		$this->_openFile($file);
   		xml_parse($this->parser, $this->xml_data);
   		$this->doneParse();
   		$this->free();
   }
   
   function _startElementHandler($parser, $name, $attribs) {
   		$this->ent_c++; //entities fix
   		$this->tag_pos++; //increases the tag position counter
       $this->stack[] = $name;
       $this->curr_tag = $this->stack[$this->tag_pos];
       $this->startElementHandler($name, $attribs);
   }

   function _endElementHandler($parser, $name) {
   		$this->ent_c++; //entites fix
   		$this->tag_pos-=1;
   		array_pop($this->stack);
   		if($this->tag_pos!=-1) {//keeps track of what the current tag is
   			$this->curr_tag = $this->stack[$this->tag_pos];
   		} else {$curr_tag=0;}
   		$this->endElementHandler($name);
   }
   
   function _dataHandler($parser, $data) {//handles the character data
   		if($this->prev_ent_c == $this->ent_c) {//if the parser is looking at the same cell
   			$this->repeat = true; //then it is a repeat
   		} else {//if not then it is not a repeat
   			$this->repeat = false;
   		}
   		$this->prev_ent_c = $this->ent_c;
   		$this->dataHandler($data); //send the data off to the parent function
   }
   
   function free() {
   		xml_parser_free($this->parser);	
   }
}
?>