<?php
require_once($path_to_root. "/includes/JsHttpRequest.php");

class Ajax extends JsHttpRequest {

	var $aCommands = array();
	var $triggers = array();
	
    function Ajax() 
    {
	  $this->JsHttpRequest($_SESSION['language']->encoding);
    }
	//
	//	This function is used in ctrl routines to activate
	//	update of ajaxified html element selected by given name/id.
	//
	function activate($trigname) {
	  if (in_ajax()) {
		$this->triggers[$trigname] = true;
	  }
	}
	//
	//	Javascript clientside redirection.
	//	This is the last command added to reponse (if any).
	//
	function redirect($url) {
	    if(in_ajax()) {
		  $this->_addCommand(true, array('n'=>'rd'),$url);
		  $this->run();
	    }
	}
	//
	// Adds an executable Javascript code.
	//
	function addScript($trigger, $sJS)
	{
		$this->_addCommand($trigger, array('n'=>'js'),$sJS);
		return $this;
	}
	//
	// Assign target attribute with data.
	//
	function addAssign($trigger, $sTarget,$sAttribute,$sData)
	{
		$this->_addCommand($trigger, array('n'=>'as','t'=>$sTarget,'p'=>$sAttribute),$sData);
		return $this;
	}
	//
	// Updates input element or label with data.
	//
	function addUpdate($trigger, $sTarget, $sData)
	{
		$this->_addCommand($trigger, array('n'=>'up','t'=>$sTarget),$sData);
		return $this;
	}
	//
	// Set disable state of element.
	//
	function addDisable($trigger, $sTarget, $sData=true)
	{
		$this->_addCommand($trigger, array('n'=>'di','t'=>$sTarget),$sData);
		return $this;
	}
	//
	// Set state of element to enabled.
	//
	function addEnable($trigger, $sTarget, $sData=true)
	{
		$this->_addCommand($trigger, array('n'=>'di','t'=>$sTarget), !$sData);
		return $this;
	}
	//
	// Set current focus.
	//
	function addFocus($trigger, $sTarget)
	{
		$this->_addCommand($trigger, array('n'=>'fc'),$sTarget);
		return $this;
	}
	//
	// Internal procedure adding command to response.
	//
	function _addCommand($trigger, $aAttributes, $mData)
	{
	  if ($this->isActive() && ($trigger !== false)) {
//		display_error('adding '.$trigger.':'.htmlentities($mData));

		$aAttributes['why'] = $trigger;
		$aAttributes['data'] = $mData;
		$this->aCommands[] = $aAttributes;
	  }
	}
	/*
	* Register binds function with ajax call parameter
	
	function register($trigger, $function) 
	{
	    if (isset($_REQUEST[$trigger])) {
		$function(&$this);
	    }
	}
	*/
	function run() {
	    
	    if (!$this->isActive()) return;

		// remove not active commands
		foreach ($this->aCommands as $idx => $com) {
		// display_error( $idx.':'.var_dump($com));
// If we should reload whole page content ignore all commands but the update.
// This is page repost equivalent, although header and footer are not reloaded.
		  if($com['n'] == 'up' && $com['t'] == '_page_body') {
			  $this->aCommands = array($com);
			  break;
		  }
		  else
		  if ($com['why'] !== true && !isset($this->triggers[$com['why']]))
			unset($this->aCommands[$idx]);
		}
	    $GLOBALS['_RESULT'] = $this->aCommands;
//	    exit();
	}
}

function in_ajax() {
    global $Ajax;
    return $Ajax->isActive();
}

?>