<?php
/**
 * THttpResponse class
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link http://www.pradosoft.com/
 * @copyright Copyright &copy; 2005 PradoSoft
 * @license http://www.pradosoft.com/license/
 * @version $Revision: $  $Date: $
 * @package System.Web
 */

/**
 * THttpResponse class
 *
 * THttpResponse implements a scheme to output response to user requests.
 *
 * THttpResponse is the default "response" module for prado application.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @version $Revision: $  $Date: $
 * @package System.Web
 * @since 3.0
 */
class THttpResponse extends TComponent implements IModule, ITextWriter
{
	/**
	 * @var string id of this module (response)
	 */
	private $_id;
	/**
	 * @var boolean whether to buffer output
	 */
	private $_bufferOutput=true;
	/**
	 * @var boolean if the application is initialized
	 */
	private $_initialized=false;
	/**
	 * @var THttpCookieCollection list of cookies to return
	 */
	private $_cookies=null;
	/**
	 * @var integer status code
	 */
	private $_status=200;

	/**
	 * Destructor.
	 * Flushes any existing content in buffer.
	 */
	public function __destruct()
	{
		if($this->_bufferOutput)
			@ob_end_flush();
		parent::__destruct();
	}

	/**
	 * Initializes the module.
	 * This method is required by IModule and is invoked by application.
	 * It starts output buffer if it is enabled.
	 * @param IApplication application
	 * @param TXmlElement module configuration
	 */
	public function init($application,$config)
	{
		if($this->_bufferOutput)
			ob_start();
		$this->_initialized=true;
	}

	/**
	 * @return string id of this module
	 */
	public function getID()
	{
		return $this->_id;
	}

	/**
	 * @param string id of this module
	 */
	public function setID($value)
	{
		$this->_id=$value;
	}


	/**
	 * @return integer time-to-live for cached session pages in minutes, this has no effect for nocache limiter. Defaults to 180.
	 */
	public function getCacheExpire()
	{
		return session_cache_expire();
	}

	/**
	 * @param integer time-to-live for cached session pages in minutes, this has no effect for nocache limiter.
	 */
	public function setCacheExpire($value)
	{
		session_cache_expire(TPropertyValue::ensureInteger($value));
	}

	/**
	 * @return string cache control method to use for session pages
	 */
	public function getCacheControl()
	{
		return session_cache_limiter();
	}

	/**
	 * @param string cache control method to use for session pages. Valid values
	 *               include none/nocache/private/private_no_expire/public
	 */
	public function setCacheControl($value)
	{
		session_cache_limiter(TPropertyValue::ensureEnum($value,array('none','nocache','private','private_no_expire','public')));
	}

	/**
	 * @return boolean whether to enable output buffer
	 */
	public function getBufferOutput()
	{
		return $this->_bufferOutput;
	}

	/**
	 * @param boolean whether to enable output buffer
	 * @throws TInvalidOperationException if session is started already
	 */
	public function setBufferOutput($value)
	{
		if($this->_initialized)
			throw new TInvalidOperationException('httpresponse_bufferoutput_unchangeable');
		else
			$this->_bufferOutput=TPropertyValue::ensureBoolean($value);
	}

	/**
	 * @return integer HTTP status code, defaults to 200
	 */
	public function getStatusCode()
	{
		return $this->_status;
	}

	/**
	 * @param integer HTTP status code
	 */
	public function setStatusCode($status)
	{
		$this->_status=TPropertyValue::ensureInteger($status);
	}

	/**
	 * @return THttpCookieCollection list of output cookies
	 */
	public function getCookies()
	{
		if($this->_cookies===null)
			$this->_cookies=new THttpCookieCollection($this);
		return $this->_cookies;
	}

	/**
	 * Outputs a string.
	 * It may not be sent back to user immediately if output buffer is enabled.
	 * @param string string to be output
	 */
	public function write($str)
	{
		echo $str;
	}

	/**
	 * Sends a file back to user.
	 * Make sure not to output anything else after calling this method.
	 * @param string file name
	 * @throws TInvalidDataValueException if the file cannot be found
	 */
	public function writeFile($fileName)
	{
		static $defaultMimeTypes=array(
			'css'=>'text/css',
			'gif'=>'image/gif',
			'jpg'=>'image/jpeg',
			'jpeg'=>'image/jpeg',
			'htm'=>'text/html',
			'html'=>'text/html',
			'js'=>'javascript/js'
		);

		if(!is_file($fileName))
			throw new TInvalidDataValueException('httpresponse_file_inexistent',$fileName);
		header('Pragma: public');
		header('Expires: 0');
		header('Cache-Component: must-revalidate, post-check=0, pre-check=0');
		$mimeType='text/plain';
		if(function_exists('mime_content_type'))
			$mimeType=mime_content_type($fileName);
		else
		{
			$ext=array_pop(explode('.',$fileName));
			if(isset($defaultMimeTypes[$ext]))
				$mimeType=$defaultMimeTypes[$ext];
		}
		$fn=basename($fileName);
		header("Content-type: $mimeType");
		header('Content-Length: '.filesize($fileName));
		header("Content-Disposition: attachment; filename=\"$fn\"");
		header('Content-Transfer-Encoding: binary');
		readfile($fileName);
	}

	/**
	 * Redirects the browser to the specified URL.
	 * The current application will be terminated after this method is invoked.
	 * @param string URL to be redirected to
	 */
	public function redirect($url)
	{
		header('Location:'.$url);
		exit();
	}

	/**
	 * Outputs the buffered content.
	 */
	public function flush()
	{
		if($this->_bufferOutput)
			ob_flush();
	}

	/**
	 * Clears any existing buffered content.
	 */
	public function clear()
	{
		if($this->_bufferOutput)
			ob_clean();
	}

	/**
	 * Sends a header.
	 * @param string header
	 */
	public function appendHeader($value)
	{
		header($value);
	}

	/**
	 * Writes a log message into error log.
	 * This method is simple wrapper of PHP function error_log.
	 * @param string The error message that should be logged
	 * @param integer where the error should go
	 * @param string The destination. Its meaning depends on the message parameter as described above
	 * @param string The extra headers. It's used when the message parameter is set to 1. This message type uses the same internal function as mail() does.
	 * @see http://us2.php.net/manual/en/function.error-log.php
	 */
	public function appendLog($message,$messageType=0,$destination='',$extraHeaders='')
	{
		error_log($message,$messageType,$destination,$extraHeaders);
	}

	/**
	 * Sends a cookie.
	 * Do not call this method directly. Operate with the result of {@link getCookies} instead.
	 * @param THttpCookie cook to be sent
	 */
	public function addCookie($cookie)
	{
		setcookie($cookie->getName(),$cookie->getValue(),$cookie->getExpire(),$cookie->getPath(),$cookie->getDomain(),$cookie->getSecure());
	}

	/**
	 * Deletes a cookie.
	 * Do not call this method directly. Operate with the result of {@link getCookies} instead.
	 * @param THttpCookie cook to be deleted
	 */
	public function removeCookie($cookie)
	{
		setcookie($cookie->getName(),null,0,$cookie->getPath(),$cookie->getDomain(),$cookie->getSecure());
	}
}

?>