<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');

/**

 * CodeIgniter

 *

 * An open source application development framework for PHP 5.1.6 or newer

 *

 * @package		CodeIgniter

 * @author		ExpressionEngine Dev Team

 * @copyright	Copyright (c) 2008 - 2011, EllisLab, Inc.

 * @license		http://codeigniter.com/user_guide/license.html

 * @link		http://codeigniter.com

 * @since		Version 1.0

 * @filesource

 */



// ------------------------------------------------------------------------



/**

 * Trackback Class

 *

 * Trackback Sending/Receiving Class

 *

 * @package		CodeIgniter

 * @subpackage	Libraries

 * @category	Trackbacks

 * @author		ExpressionEngine Dev Team

 * @link		http://codeigniter.com/user_guide/libraries/trackback.html

 */

class CI_Trackback {



	var $time_format	= 'local';

	var $charset		= 'UTF-8';

	var $data			= array('url' => '', 'title' => '', 'excerpt' => '', 'blog_name' => '', 'charset' => '');

	var $convert_ascii	= TRUE;

	var $response		= '';

	var $error_msg		= array();



	/**

	 * Constructor

	 *

	 * @access	public

	 */

	public function __construct()

	{

		log_message('debug', "Trackback Class Initialized");

	}



	// --------------------------------------------------------------------



	/**

	 * Send Trackback

	 *

	 * @access	public

	 * @param	array

	 * @return	bool

	 */

	function send($tb_data)

	{

		if ( ! is_array($tb_data))

		{

			$this->set_error('The send() method must be passed an array');

			return FALSE;

		}



		// Pre-process the Trackback Data

		foreach (array('url', 'title', 'excerpt', 'blog_name', 'ping_url') as $item)

		{

			if ( ! isset($tb_data[$item]))

			{

				$this->set_error('Required item missing: '.$item);

				return FALSE;

			}



			switch ($item)

			{

				case 'ping_url'	: $$item = $this->extract_urls($tb_data[$item]);

					break;

				case 'excerpt'	: $$item = $this->limit_characters($this->convert_xml(strip_tags(stripslashes($tb_data[$item]))));

					break;

				case 'url'		: $$item = str_replace('&#45;', '-', $this->convert_xml(strip_tags(stripslashes($tb_data[$item]))));

					break;

				default			: $$item = $this->convert_xml(strip_tags(stripslashes($tb_data[$item])));

					break;

			}



			// Convert High ASCII Characters

			if ($this->convert_ascii == TRUE)

			{

				if ($item == 'excerpt')

				{

					$$item = $this->convert_ascii($$item);

				}

				elseif ($item == 'title')

				{

					$$item = $this->convert_ascii($$item);

				}

				elseif ($item == 'blog_name')

				{

					$$item = $this->convert_ascii($$item);

				}

			}

		}



		// Build the Trackback data string

		$charset = ( ! isset($tb_data['charset'])) ? $this->charset : $tb_data['charset'];



		$data = "url=".rawurlencode($url)."&title=".rawurlencode($title)."&blog_name=".rawurlencode($blog_name)."&excerpt=".rawurlencode($excerpt)."&charset=".rawurlencode($charset);



		// Send Trackback(s)

		$return = TRUE;

		if (count($ping_url) > 0)

		{

			foreach ($ping_url as $url)

			{

				if ($this->process($url, $data) == FALSE)

				{

					$return = FALSE;

				}

			}

		}



		return $return;

	}



	// --------------------------------------------------------------------



	/**

	 * Receive Trackback  Data

	 *

	 * This function simply validates the incoming TB data.

	 * It returns FALSE on failure and TRUE on success.

	 * If the data is valid it is set to the $this->data array

	 * so that it can be inserted into a database.

	 *

	 * @access	public

	 * @return	bool

	 */

	function receive()

	{

		foreach (array('url', 'title', 'blog_name', 'excerpt') as $val)

		{

			if ( ! isset($_POST[$val]) OR $_POST[$val] == '')

			{

				$this->set_error('The following required POST variable is missing: '.$val);

				return FALSE;

			}



			$this->data['charset'] = ( ! isset($_POST['charset'])) ? 'auto' : strtoupper(trim($_POST['charset']));



			if ($val != 'url' && function_exists('mb_convert_encoding'))

			{

				$_POST[$val] = mb_convert_encoding($_POST[$val], $this->charset, $this->data['charset']);

			}



			$_POST[$val] = ($val != 'url') ? $this->convert_xml(strip_tags($_POST[$val])) : strip_tags($_POST[$val]);



			if ($val == 'excerpt')

			{

				$_POST['excerpt'] = $this->limit_characters($_POST['excerpt']);

			}



			$this->data[$val] = $_POST[$val];

		}



		return TRUE;

	}



	// --------------------------------------------------------------------



	/**

	 * Send Trackback Error Message

	 *

	 * Allows custom errors to be set.  By default it

	 * sends the "incomplete information" error, as that's

	 * the most common one.

	 *

	 * @access	public

	 * @param	string

	 * @return	void

	 */

	function send_error($message = 'Incomplete Information')

	{

		echo "<?xml version=\"1.0\" encoding=\"utf-8\"?".">\n<response>\n<error>1</error>\n<message>".$message."</message>\n</response>";

		exit;

	}



	// --------------------------------------------------------------------



	/**

	 * Send Trackback Success Message

	 *

	 * This should be called when a trackback has been

	 * successfully received and inserted.

	 *

	 * @access	public

	 * @return	void

	 */

	function send_success()

	{

		echo "<?xml version=\"1.0\" encoding=\"utf-8\"?".">\n<response>\n<error>0</error>\n</response>";

		exit;

	}



	// --------------------------------------------------------------------



	/**

	 * Fetch a particular item

	 *

	 * @access	public

	 * @param	string

	 * @return	string

	 */

	function data($item)

	{

		return ( ! isset($this->data[$item])) ? '' : $this->data[$item];

	}



	// --------------------------------------------------------------------



	/**

	 * Process Trackback

	 *

	 * Opens a socket connection and passes the data to

	 * the server.  Returns TRUE on success, FALSE on failure

	 *

	 * @access	public

	 * @param	string

	 * @param	string

	 * @return	bool

	 */

	function process($url, $data)

	{

		$target = parse_url($url);



		// Open the socket

		if ( ! $fp = @fsockopen($target['host'], 80))

		{

			$this->set_error('Invalid Connection: '.$url);

			return FALSE;

		}



		// Build the path

		$ppath = ( ! isset($target['path'])) ? $url : $target['path'];



		$path = (isset($target['query']) && $target['query'] != "") ? $ppath.'?'.$target['query'] : $ppath;



		// Add the Trackback ID to the data string

		if ($id = $this->get_id($url))

		{

			$data = "tb_id=".$id."&".$data;

		}



		// Transfer the data

		fputs ($fp, "POST " . $path . " HTTP/1.0\r\n" );

		fputs ($fp, "Host: " . $target['host'] . "\r\n" );

		fputs ($fp, "Content-type: application/x-www-form-urlencoded\r\n" );

		fputs ($fp, "Content-length: " . strlen($data) . "\r\n" );

		fputs ($fp, "Connection: close\r\n\r\n" );

		fputs ($fp, $data);



		// Was it successful?

		$this->response = "";



		while ( ! feof($fp))

		{

			$this->response .= fgets($fp, 128);

		}

		@fclose($fp);





		if (stristr($this->response, '<error>0</error>') === FALSE)

		{

			$message = 'An unknown error was encountered';



			if (preg_match("/<message>(.*?)<\/message>/is", $this->response, $match))

			{

				$message = trim($match['1']);

			}



			$this->set_error($message);

			return FALSE;

		}



		return TRUE;

	}



	// --------------------------------------------------------------------



	/**

	 * Extract Trackback URLs

	 *

	 * This function lets multiple trackbacks be sent.

	 * It takes a string of URLs (separated by comma or

	 * space) and puts each URL into an array

	 *

	 * @access	public

	 * @param	string

	 * @return	string

	 */

	function extract_urls($urls)

	{

		// Remove the pesky white space and replace with a comma.

		$urls = preg_replace("/\s*(\S+)\s*/", "\\1,", $urls);



		// If they use commas get rid of the doubles.

		$urls = str_replace(",,", ",", $urls);



		// Remove any comma that might be at the end

		if (substr($urls, -1) == ",")

		{

			$urls = substr($urls, 0, -1);

		}



		// Break into an array via commas

		$urls = preg_split('/[,]/', $urls);



		// Removes duplicates

		$urls = array_unique($urls);



		array_walk($urls, array($this, 'validate_url'));



		return $urls;

	}



	// --------------------------------------------------------------------



	/**

	 * Validate URL

	 *

	 * Simply adds "http://" if missing

	 *

	 * @access	public

	 * @param	string

	 * @return	string

	 */

	function validate_url($url)

	{

		$url = trim($url);



		if (substr($url, 0, 4) != "http")

		{

			$url = "http://".$url;

		}

	}



	// --------------------------------------------------------------------



	/**

	 * Find the Trackback URL's ID

	 *

	 * @access	public

	 * @param	string

	 * @return	string

	 */

	function get_id($url)

	{

		$tb_id = "";



		if (strpos($url, '?') !== FALSE)

		{

			$tb_array = explode('/', $url);

			$tb_end   = $tb_array[count($tb_array)-1];



			if ( ! is_numeric($tb_end))

			{

				$tb_end  = $tb_array[count($tb_array)-2];

			}



			$tb_array = explode('=', $tb_end);

			$tb_id	= $tb_array[count($tb_array)-1];

		}

		else

		{

			$url = rtrim($url, '/');



			$tb_array = explode('/', $url);

			$tb_id	= $tb_array[count($tb_array)-1];



			if ( ! is_numeric($tb_id))

			{

				$tb_id  = $tb_array[count($tb_array)-2];

			}

		}



		if ( ! preg_match ("/^([0-9]+)$/", $tb_id))

		{

			return FALSE;

		}

		else

		{

			return $tb_id;

		}

	}



	// --------------------------------------------------------------------



	/**

	 * Convert Reserved XML characters to Entities

	 *

	 * @access	public

	 * @param	string

	 * @return	string

	 */

	function convert_xml($str)

	{

		$temp = '__TEMP_AMPERSANDS__';



		$str = preg_replace("/&#(\d+);/", "$temp\\1;", $str);

		$str = preg_replace("/&(\w+);/",  "$temp\\1;", $str);



		$str = str_replace(array("&","<",">","\"", "'", "-"),

							array("&amp;", "&lt;", "&gt;", "&quot;", "&#39;", "&#45;"),

							$str);



		$str = preg_replace("/$temp(\d+);/","&#\\1;",$str);

		$str = preg_replace("/$temp(\w+);/","&\\1;", $str);



		return $str;

	}



	// --------------------------------------------------------------------



	/**

	 * Character limiter

	 *

	 * Limits the string based on the character count. Will preserve complete words.

	 *

	 * @access	public

	 * @param	string

	 * @param	integer

	 * @param	string

	 * @return	string

	 */

	function limit_characters($str, $n = 500, $end_char = '&#8230;')

	{

		if (strlen($str) < $n)

		{

			return $str;

		}



		$str = preg_replace("/\s+/", ' ', str_replace(array("\r\n", "\r", "\n"), ' ', $str));



		if (strlen($str) <= $n)

		{

			return $str;

		}



		$out = "";

		foreach (explode(' ', trim($str)) as $val)

		{

			$out .= $val.' ';

			if (strlen($out) >= $n)

			{

				return trim($out).$end_char;

			}

		}

	}



	// --------------------------------------------------------------------



	/**

	 * High ASCII to Entities

	 *

	 * Converts Hight ascii text and MS Word special chars

	 * to character entities

	 *

	 * @access	public

	 * @param	string

	 * @return	string

	 */

	function convert_ascii($str)

	{

		$count	= 1;

		$out	= '';

		$temp	= array();



		for ($i = 0, $s = strlen($str); $i < $s; $i++)

		{

			$ordinal = ord($str[$i]);



			if ($ordinal < 128)

			{

				$out .= $str[$i];

			}

			else

			{

				if (count($temp) == 0)

				{

					$count = ($ordinal < 224) ? 2 : 3;

				}



				$temp[] = $ordinal;



				if (count($temp) == $count)

				{

					$number = ($count == 3) ? (($temp['0'] % 16) * 4096) + (($temp['1'] % 64) * 64) + ($temp['2'] % 64) : (($temp['0'] % 32) * 64) + ($temp['1'] % 64);



					$out .= '&#'.$number.';';

					$count = 1;

					$temp = array();

				}

			}

		}



		return $out;

	}



	// --------------------------------------------------------------------



	/**

	 * Set error message

	 *

	 * @access	public

	 * @param	string

	 * @return	void

	 */

	function set_error($msg)

	{

		log_message('error', $msg);

		$this->error_msg[] = $msg;

	}



	// --------------------------------------------------------------------



	/**

	 * Show error messages

	 *

	 * @access	public

	 * @param	string

	 * @param	string

	 * @return	string

	 */

	function display_errors($open = '<p>', $close = '</p>')

	{

		$str = '';

		foreach ($this->error_msg as $val)

		{

			$str .= $open.$val.$close;

		}



		return $str;

	}



}

// END Trackback Class



/* End of file Trackback.php */

/* Location: ./system/libraries/Trackback.php */