e107inc/e107

<?php
/*
 * e107 website system
 *
 * Copyright (C) 2008-2009 e107 Inc (e107.org)
 * Released under the terms and conditions of the
 * GNU General Public License (http://www.gnu.org/licenses/gpl.txt)
 *
 *
 *
 * $Source: /cvs_backup/e107_0.8/e107_handlers/override_class.php,v $
 * $Revision$
 * $Date$
 * $Author$
 */

namespace e107;

if (!defined('e107_INIT')) { exit; }

/*
 * USAGE
 * In user code, to override an existing function...
 *
 * $override->override_function('original_func_name','mynew_function_name',['optional_include_file_from_root']);
 *
 * In e107 code...
 * if ($over_func_name = $override->override_check('original_func_name')) {
 *    $result=call_user_func($over_func_name, params...);
 * }
 * 
 *
 */
//XXX IMPORTANT: // do not use e107 specific functions in this file - it may break secure_img_handler. 


/**
 *
 */
class override {
    
    protected $functions = array();
    protected $includes = array();
    

    
    /**
     * Replace an existing function or class method
     * @param string|array $override - function name or class::method
     * @param string|array $function - new function name or class::method 
     * @param $include (optional) - file to include from root dir. 
     * @example e107::getOverride()->replace('secure_image::create_code', 'myclass::mymethod');
     */
    public function replace($override,$function,$include='') // Alias with class functionality. 
    {
        if(is_array($override))
        {
            $arr = $override[0]."::".$override[1];        
        }
        else
        {
            $arr = $override;    
        }
        
        $this->override_function($arr, $function, $include);
    }

    /**
     * check if an override exists
     * @param object|string $override : function name or class object
     * @param string $method : method name when 'class' is used for $override
     * @example if ($user_func = e107::getOverride()->check($this,'secure_image'))
                {
                     return call_user_func($user_func);
                }
     * @return mixed

     */
    public function check($override,$method='')
    {
        
        if($method != '')
        {            
            $class = get_class($override);
            $override = $class."::".$method;    
        }
        return $this->override_check($override);    
    }


    /**
     * @param $override
     * @param $function
     * @param $include
     * @return void
     */
    function override_function($override, $function, $include)
    {
        if ($include)
        {
            $this->includes[$override] = $include;
        }
        else if (isset($this->includes[$override]))
        {
            unset($this->includes[$override]);
        }
        
        $this->functions[$override] = $function;
    }


    /**
     * @param $override
     * @return false|mixed|string
     */
    function override_check($override)
    {        
        if (isset($this->includes[$override])) 
        {            
            if (file_exists($this->includes[$override]))
            {
                include_once($this->includes[$override]);
            }    
        } 
        
        if($override && isset($this->functions[$override]))
        {
            $tmp =  (strpos($this->functions[$override],"::")) ?  explode("::",$this->functions[$override]) : $this->functions[$override];
        }
        else
        {
            $tmp = false;
        } 
        if(is_array($tmp) && class_exists($tmp[0]))
        {
            $cl = new $tmp[0];
             if(method_exists($cl,$tmp[1]))
             {
                 return $this->functions[$override];
             }    
        }    
    
        if ($override && isset($this->functions[$override]) && function_exists($this->functions[$override]))
        {
            
            return $this->functions[$override];
        }
        else
        {
            return false;
        }

    }
}