<?php 
/**
 * 	 Demo Code
 *  
 *   This program is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program. If not, see <http://www.gnu.org/licenses/gpl.txt/>.
 * 
 *   The copyright holder may be reached by emailing john@kleijnweb.nl
 * 	 
 *   
 * 
 * @copyright 	Copyright (C) 2010  Kleijn Web Development
 * @license 	http://www.gnu.org/licenses/gpl.txt GNU General Public License
 */
namespace kwd\blog\virtualproxy;

/**
 * Code generator virtual proxies 
 *
 * @category virtualproxy
 * @package kwd\blog\virtualproxy
 */
class ProxyGenerator
{
	/**
	 * @var ReflectionClass
	 */
	private $_refl;
	
	/**
	 * @var string
	 */
	private $_namespace;
	
	/**
	 * Create a new generator
	 * 
	 * @param string $namespace
	 */
	public function __construct($namespace = null)
	{
		$this->setNamespace($namespace);
	}
	
	/**
	 * Prefix class names with this namespace
	 * 
	 * @param string $namespace
	 * @return kwd\blog\virtualproxy\ProxyGenerator
	 */
	public function setNamespace($namespace)
	{
		$this->_namespace = $namespace;
		
		return $this;
	}
	
	public function getProxyName($subjectName)
	{
		return "{$subjectName}Proxy";
	}
	
	/**
	 * Generate the code for a proxy by subject class
	 * 
	 * @param string $subjectName
	 * @return string
	 */
	public function generate($subjectName)
	{
		if(strpos($subjectName, '\\') !== false)
		{
			$segs = explode('\\', $subjectName);
			
			$subjectName = array_pop($segs);
			
			$namespace = implode('\\', $segs);
		}
		else
		{
			$namespace = $this->_namespace;
		}
		
		$fullSubjectName = $namespace ? "\\$namespace\\$subjectName" : $subjectName;
		
		$this->_refl = new \ReflectionClass($fullSubjectName);
		
		$proxyName = $this->getProxyName($subjectName);
		
		if(class_exists($namespace ? "\\$namespace\\$proxyName" : $proxyName, false))
		{
			require_once 'Exception.php';
			
			throw new Exception("Proxy '$proxyName' already exists");
		}
		
		$output = $namespace ? "namespace $namespace;\n\n" : "";
		
		$output .= "class $proxyName extends $subjectName\n{\n"
			. "\tprivate \$_loader;\n"
			. "\tprivate \$_subject;\n"
			. "\n";
		
		foreach($this->_refl->getMethods(\ReflectionMethod::IS_PUBLIC | \ReflectionMethod::IS_PROTECTED) as $method)
		{
			$paramStrings = array();
			$delegationParamStrings = array();
			
			foreach($method->getParameters() as $param)
			{
				$paramString =
					($param->isPassedByReference() ? '&' : '') 
					. ("\${$param->getName()}");
					
				if($param->getClass() && $param->getClass()->getName())
				{
					$paramString = "\\{$param->getClass()->getName()} {$paramString}";
				}
				
				$paramString .= ($param->isDefaultValueAvailable() ? " = " . var_export($param->getDefaultValue(), true) : '');
				
				$paramStrings[] = $paramString;
				
				$delegationParamStrings[] = "\${$param->getName()}";
			}
			
			$paramsString = implode(', ', $paramStrings);
			$delegationParamsStrings = implode(', ', $delegationParamStrings);
			
			$output .= "\n\tpublic function {$method->getName()}($paramsString)\n\t{\n"
				. "\t\treturn \$this->_getSubject()->{$method->getName()}($delegationParamsStrings);\n"
				. "\t}\n";
		}
		
		$output .= "\n\tprivate function _getSubject()\n\t{\n"
			. "\t\tif(!\$this->_subject)\n\t\t{\n"
			. "\t\t\t\$this->_subject = \$this->_loader->load();\n"
			. "\t\t}\n\n"
			. "\t\treturn \$this->_subject;\n"
			. "\t}\n"
			. "}";
		var_dump($output);
		return $output;
	}
}