<?php

/*

Plugin Name: Plaintext URLs 

Description: Parse plaintext URLs as links

Version: 1.0

Author: Janis Elsts



ModuleCategory: parser

ModuleClassName: blcPlaintextURL

ModuleContext: on-demand

ModuleLazyInit: true



ModulePriority: 800

*/



class blcPlaintextURL extends blcParser {

	var $supported_formats = array('html', 'plaintext');

	

	//Regexp for detecting plaintext URLs lifted from make_clickable()

	var $url_regexp = '#(?<=[\s>\]])(\()?([\w]+?://(?:[\w\\x80-\\xff\#$%&~/=?@\[\](+-]|[.,;:](?![\s<]|(\))?([\s]|$))|(?(1)\)(?![\s<.,;:]|$)|\)))+)#is';

	

	//Used by the edit and unlink callbacks

	var $old_url = '';

	var $new_url = '';

			

  /**

   * Parse a string for plaintext URLs

   *

   * @param string $content The text to parse.

   * @param string $base_url The base URL. Ignored.  

   * @param string $default_link_text Default link text.

   * @return array An array of new blcLinkInstance objects.  

   */

	function parse($content, $base_url = '', $default_link_text = ''){

		//Don't want to detect URLs inside links or tag attributes - 

		//there are already other parsers for that.

		

		//Avoid <a href="http://...">http://...</a>

		$content = preg_replace('#<a[^>]*>.*?</a>#si', '', $content);

		//HTML tags are treated as natural boundaries for plaintext URLs 

		//(since we strip tags, we must place another boundary char where they were).

		//The closing tag of [shortcodes] is also treated as a boundary.  

		$content = str_replace(array('<', '>', '[/'), array("\n<", ">\n", "\n[/"), $content);

		//Finally, kill all tags.

		$content = strip_tags($content);

		

		//Find all URLs

		$found = preg_match_all(

			$this->url_regexp, 

			$content, 

			$matches

		);

		

		$instances = array();

		

		if ( $found ){

			//Create a new instance for each match

			foreach($matches[2] as $match){

				//Do a little bit of validation

				$url = esc_url_raw(trim($match));

				if ( empty($url) ){

					continue;

				}

				if ( function_exists('filter_var') ){

					//Note: filter_var() is no panacea as it accepts many invalid URLs  

					if ( !filter_var($url, FILTER_VALIDATE_URL, FILTER_FLAG_HOST_REQUIRED) ){

						continue;

					}

				}

				$parts = @parse_url($url);

				if ( empty($parts['host']) || !strpos($parts['host'], '.') ){

					continue;

				}

				

				//Create a new link instance.

				$instance = new blcLinkInstance();

				    

			    $instance->set_parser($this);

			    $instance->raw_url = $match;

			    $instance->link_text = $match;

			    

			    $link_obj = new blcLink($url); //Creates or loads the link

			    $instance->set_link($link_obj);

			    

			    $instances[] = $instance;

			}

		}

		

		return $instances;

	}	

	

  /**

   * Change all occurences of a given plaintext URLs to a new URL. 

   *

   * @param string $content Look for URLs in this string.

   * @param string $new_url Change them to this URL.

   * @param string $old_url The URL to look for.

   * @param string $old_raw_url The raw, not-normalized URL. Optional. 

   *

   * @return array|WP_Error If successful, the return value will be an associative array with two

   * keys : 'content' - the modified content, and 'raw_url' - the new raw, non-normalized URL used

   * for the modified links. In most cases, the returned raw_url will be equal to the new_url.

   */

	function edit($content, $new_url, $old_url, $old_raw_url = ''){

		$this->new_url = $new_url;

		if ( empty($old_raw_url) ){

			$this->old_url = $old_url;

		} else {

			$this->old_url = $old_raw_url;

		}

		

		return array(

			'content' => preg_replace_callback($this->url_regexp, array(&$this, 'edit_callback'), $content),

			'raw_url' => $new_url,

			'link_text' => $new_url,

		);

	}

	

	function edit_callback($match){

		if ( $match[2] == $this->old_url ){

			return $this->new_url;

		} else {

			return $match[0];

		}

	}

	

	

  /**

   * Remove all occurences of a specific plaintext URL.

   *

   * @param string $content	Look for URLs in this string.

   * @param string $url The URL to look for.

   * @param string $raw_url The raw, non-normalized version of the URL to look for. Optional.

   * @return string Input string with all matching plaintext URLs removed. 

   */

	function unlink($content, $url, $raw_url = ''){

		if ( empty($raw_url) ){

			$this->old_url = $url;

		} else {

			$this->old_url = $raw_url;

		}

		

		return preg_replace_callback($this->url_regexp, array(&$this, 'unlink_callback'), $content);

	}

	

	function unlink_callback($match){

		if ( $match[2] == $this->old_url ){

			return '';

		} else {

			return $match[0];

		}

	}

}

?>