<?php

/**
* 
* Parse for links to wiki pages.
*
* @category Text
* 
* @package Text_Wiki
* 
* @author Paul M. Jones <pmjones@php.net>
* 
* @license LGPL
* 
* @version $Id: Wikilink.php,v 1.9 2006/12/08 08:23:51 justinpatrin Exp $
* 
*/

/**
* 
* Parse for links to wiki pages.
*
* Wiki page names are typically in StudlyCapsStyle made of
* WordsSmashedTogether.
*
* You can also create described links to pages in this style:
* [WikiPageName nice text link to use for display]
*
* The token options for this rule are:
*
* 'page' => the wiki page name.
* 
* 'text' => the displayed link text.
* 
* 'anchor' => a named anchor on the target wiki page.
* 
* @category Text
*
* @package Text_Wiki
*
* @author Paul M. Jones <pmjones@php.net>
* 
*/

class Text_Wiki_Parse_Wikilink extends Text_Wiki_Parse {
	
    var $conf = array (
                       'ext_chars' => false,
                       'utf-8' => false
    );
	
	/**
	* 
	* Constructor.
	* 
	* We override the Text_Wiki_Parse constructor so we can
	* explicitly comment each part of the $regex property.
	* 
	* @access public
	* 
	* @param object &$obj The calling "parent" Text_Wiki object.
	* 
	*/
	
	function Text_Wiki_Parse_Wikilink(&$obj)
	{
		parent::Text_Wiki_Parse($obj);
		
        if ($this->getConf('utf-8')) {
			$upper = 'A-Z\p{Lu}';
			$lower = 'a-z0-9\p{Ll}';
			$either = 'A-Za-z0-9\p{L}';
        } else if ($this->getConf('ext_chars')) {
        	// use an extended character set; this should
        	// allow for umlauts and so on.  taken from the
        	// Tavi project defaults.php file.
			$upper = 'A-Z\xc0-\xde';
			$lower = 'a-z0-9\xdf-\xfe';
			$either = 'A-Za-z0-9\xc0-\xfe';
		} else {
			// the default character set, should be fine
			// for most purposes.
			$upper = "A-Z";
			$lower = "a-z0-9";
			$either = "A-Za-z0-9";
		}
		
        // build the regular expression for finding WikiPage names.
		$this->regex =
			"(!?" .			     // START WikiPage pattern (1)
            "[$upper]" .       // 1 upper
            "[$either]*" .     // 0+ alpha or digit
            "[$lower]+" .      // 1+ lower or digit
            "[$upper]" .       // 1 upper
            "[$either]*" .     // 0+ or more alpha or digit
			")" .				 // END WikiPage pattern (/1)
			"((\#" .			 // START Anchor pattern (2)(3)
            "[$either]" .      // 1 alpha
			"(" .				 // start sub pattern (4)
            "[-_$either:.]*" . // 0+ dash, alpha, digit, underscore, colon, dot
            "[-_$either]" .    // 1 dash, alpha, digit, or underscore
			")?)?)";			 // end subpatterns (/4)(/3)(/2)
	}
	
	
	/**
	* 
	* First parses for described links, then for standalone links.
	* 
	* @access public
	* 
	* @return void
	* 
	*/
	
	function parse()
	{
		// described wiki links
        $tmp_regex = '/\[' . $this->regex . ' (.+?)\]/'.($this->getConf('utf-8') ? 'u' : '');
		$this->wiki->source = preg_replace_callback(
			$tmp_regex,
			array(&$this, 'processDescr'),
			$this->wiki->source
		);
		
		// standalone wiki links
        if ($this->getConf('utf-8')) {
			$either = 'A-Za-z0-9\p{L}';
        } else if ($this->getConf('ext_chars')) {
			$either = "A-Za-z0-9\xc0-\xfe";
		} else {
			$either = "A-Za-z0-9";
		}
		
        $tmp_regex = "/(^|[^{$either}\-_]){$this->regex}/".($this->getConf('utf-8') ? 'u' : '');
		$this->wiki->source = preg_replace_callback(
			$tmp_regex,
			array(&$this, 'process'),
			$this->wiki->source
		);
	}
	
	
	/**
	* 
	* Generate a replacement for described links.
	* 
	* @access public
	*
	* @param array &$matches The array of matches from parse().
	*
	* @return A delimited token to be used as a placeholder in
	* the source text, plus any text priot to the match.
	*
	*/
	
	function processDescr(&$matches)
	{
		// set the options
		$options = array(
			'page'   => $matches[1],
			'text'   => $matches[5],
			'anchor' => $matches[3]
		);
		
		// create and return the replacement token and preceding text
		return $this->wiki->addToken($this->rule, $options); // . $matches[7];
	}
	
	
	/**
	* 
	* Generate a replacement for standalone links.
	* 
	* 
	* @access public
	*
	* @param array &$matches The array of matches from parse().
	*
	* @return A delimited token to be used as a placeholder in
	* the source text, plus any text prior to the match.
	*
	*/
	
	function process(&$matches)
	{
		// when prefixed with !, it's explicitly not a wiki link.
		// return everything as it was.
		if ($matches[2]{0} == '!') {
			return $matches[1] . substr($matches[2], 1) . $matches[3];
		}
		
		// set the options
		$options = array(
			'page' => $matches[2],
			'text' => $matches[2] . $matches[3],
			'anchor' => $matches[3]
		);
		
		// create and return the replacement token and preceding text
		return $matches[1] . $this->wiki->addToken($this->rule, $options);
	}
}
?>