Source for file ClassMethodsActionSource.class.php

<?php
 
require_once HARMONI."actionHandler/ActionSource.abstract.php";
 
/**
 * The ClassMethodsActionSource looks for actions as methods located within a class. The action names correspond to a method
 * of the same name within a class. The class name is the same as module name.
 *
 * @package harmoni.actions.sources
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: ClassMethodsActionSource.class.php,v 1.6 2007/09/04 20:25:29 adamfranco Exp $
 */
class ClassMethodsActionSource extends ActionSource{
 
    /**
     * @var string $_basePath The base path on the filesystem to look for module folders.
     * @access private
     ***/
    var $_basePath;
    
    /**
     * @var string $_fileExtension The extension to add onto action names to locate their associated files.
     * @access private
     ***/
    var $_fileExtension;
    
    /**
     * Constructor
     * @param string $basePath The base path on the filesystem which contains the module class declarations.
     * @param string $fileExtension The extension to add onto module names to find the files, such that
     *  the module "main" might look for a file named "main.class.php" with a file extension of ".class.php".
     * @return void 
     * @access public
     */
    function ClassMethodsActionSource($basePath, $fileExtension) {
        $this->_basePath = ereg_replace(DIRECTORY_SEPARATOR."$", "", $basePath);
        $this->_fileExtension = $fileExtension;
    }
    
    /**
     * Checks to see if a given modules/action pair exists for execution within this source.
     * @param string $module 
     * @param string $action 
     * @access public
     * @return boolean 
     */
    function actionExists($module, $action)
    {
        $fullPath = $this->_mkFullPath($module, $action);
        if (file_exists($fullPath)) {
            include_once($fullPath);
            
            if (class_exists($module)) {
                $class = @new $module;
                
                if (method_exists($class, $action)) {
                    unset($class);
                    return true;
                }
                unset($class);
            }
        }
        return false;
    }
    
    /**
     * Makes a full pathname to an action file.
     * @access private
     * @return string 
     */
    function _mkFullPath($module, $action)
    {
        
        return $this->_basePath . DIRECTORY_SEPARATOR . $module . $this->_fileExtension;
    }
    
    /**
     * Executes the specified action in the specified module, using the Harmoni object as a base.
     * @param string $module The module in which to execute.
     * @param string $action The specific action to execute.
     * @param ref object $harmoni A reference to a {@link Harmoni} object.
     * @access public
     * @return ref mixed A {@link Layout} or TRUE/FALSE
     */
    function executeAction($module, $action, $harmoni)
    {
        $fullPath = $this->_mkFullPath($module, $action);
        if (!$this->actionExists($module, $action)) {
            throwError( new Error("ClassesActionSource::executeAction($module, $action) - could not proceed because the file to include does not exist!", "ActionHandler", true));
        }
        
        include_once($fullPath);
        
        if (!class_exists($module)) {
            throwError( new Error("ClassesActionSource::executeAction($module, $action) - could not proceed because the class name '$action' is not defined!","ActionHandler", true));
        }
        
        $class = @new $module;
        
        $method = $action;
        
        if (!method_exists($class, $method)) {
            throwError( new Error("ClassesActionSource::executeAction($module, $action) - could not proceed because the method '$method()' is not defined in the class '$action'!","ActionHandler", true));
        }
        
        $result =$class->$method($harmoni);
        
        return $result;
    }
}