<?php
/* vim: set expandtab tabstop=4 shiftwidth=4: */
// +----------------------------------------------------------------------+
// | PHP version 4														|
// +----------------------------------------------------------------------+
// | Copyright (c) 1997-2003 The PHP Group								|
// +----------------------------------------------------------------------+
// | This source file is subject to version 2.0 of the PHP license,	   |
// | that is bundled with this package in the file LICENSE, and is		|
// | available through the world-wide-web at							  |
// | http://www.php.net/license/2_02.txt.								 |
// | If you did not receive a copy of the PHP license and are unable to   |
// | obtain it through the world-wide-web, please send a note to		  |
// | license@php.net so we can mail you a copy immediately.			   |
// +----------------------------------------------------------------------+
// | Authors: Paul M. Jones <pmjones@ciaweb.net>						  |
// +----------------------------------------------------------------------+
//
// $Id: toc.php,v 1.2 2004/01/31 17:09:46 pmjones Exp $


/**
* 
* This class implements a Text_Wiki_Rule to find all heading tokens and
* build a table of contents.  The %%TOC%% tag gets replaced with a list
* of all the level-2 through level-6 headings.
*
* @author Paul M. Jones <pmjones@ciaweb.net>
*
* @package Text_Wiki
*
*/


class Text_Wiki_Rule_toc extends Text_Wiki_Rule {
	
	
	/**
	* 
	* The regular expression used to parse the source text and find
	* matches conforming to this rule.  Used by the parse() method.
	* 
	* @access public
	* 
	* @var string
	* 
	* @see parse()
	* 
	*/
	
	var $regex = "/%%TOC%%/m";
	
	
	/**
	* 
	* The collection of headings (text and levels).
	* 
	* @access public
	* 
	* @var array
	* 
	* @see _getEntries()
	* 
	*/
	
	var $entry = array();
	
	
	/**
	* 
	* Custom parsing (have to process heading entries first).
	* 
	* @access public
	* 
	* @see Text_Wiki::parse()
	* 
	*/
	
	function parse()
	{
		$this->_getEntries();
		parent::parse();
	}
	
	
	/**
	* 
	* Generates a replacement for the matched text.  Token options are:
	* 
	* 'type' => ['list_start'|'list_end'|'item_end'|'item_end'|'target']
	*
	* 'level' => The heading level (1-6).
	*
	* 'count' => Which heading this is in the list.
	* 
	* @access public
	*
	* @param array &$matches The array of matches from parse().
	*
	* @return string A token indicating the TOC collection point.
	*
	*/
	
	function process(&$matches)
	{
		$output = $this->addToken(array('type' => 'list_start'));
		
		foreach ($this->entry as $key => $val) {
		
			$options = array(
				'type' => 'item_start',
				'count' => $val['count'],
				'level' => $val['level']
			);
			
			$output .= $this->addToken($options);
			
			$output .= $val['text'];
			
			$output .= $this->addToken(array('type' => 'item_end'));
		}
		
		$output .= $this->addToken(array('type' => 'list_end'));
		return $output;
	}
	
	
	/**
	* 
	* Finds all headings in the text and saves them in $this->entry.
	* 
	* @access private
	*
	* @return void
	* 
	*/
	
	function _getEntries()
	{
		// the wiki delimiter
		$delim = $this->_wiki->delim;
		
		// list of all TOC entries (h2, h3, etc)
		$this->entry = array();
		
		// the new source text with TOC entry tokens
		$newsrc = '';
		
        // when passing through the parsed source text, keep track of when
        // we are in a delimited section
        $in_delim = false;
        
        // when in a delimited section, capture the token key number
        $key = '';
        
        // TOC entry count
        $count = 0;
        
        // pass through the parsed source text character by character
        $k = strlen($this->_wiki->_source);
        for ($i = 0; $i < $k; $i++) {
            
            // the current character
            $char = $this->_wiki->_source{$i};
            
            // are alredy in a delimited section?
            if ($in_delim) {
            
                // yes; are we ending the section?
                if ($char == $delim) {
                    
                    // yes, get the replacement text for the delimited
                    // token number and unset the flag.
                    $key = (int)$key;
                    $rule = $this->_wiki->_tokens[$key][0];
                    $opts = $this->_wiki->_tokens[$key][1];
                    $in_delim = false;
                    
                    // is the key a start heading token
                    // of level 2 or deeper?
                    if ($rule == 'heading' &&
                    	$opts['type'] == 'start' &&
                    	$opts['level'] > 1) {
                    	
                    	// yes, add a TOC target link to the
                    	// tokens array...
						$token = $this->addToken(
							array(
								'type' => 'target',
								'count' => $count,
								'level' => $opts['level']
							)
						);
						
						// ... and to the new source, before the
						// heading-start token.
						$newsrc .= $token . $delim . $key . $delim;
						
						// retain the toc item
						$this->entry[] = array (
							'count' => $count,
							'level' => $opts['level'],
							'text' => $opts['text']
						);
						
						// increase the count for the next entry
						$count++;
						
                    } else {
                    	// not a heading-start of 2 or deeper.
                    	// re-add the delimited token number
                    	// as it was in the original source.
                    	$newsrc .= $delim . $key . $delim;
                    }
                    
                } else {
                
                    // no, add to the delimited token key number
                    $key .= $char;
                    
                }
                
            } else {
            	
            	// not currently in a delimited section.
            	// are we starting into a delimited section?
                if ($char == $delim) {
                	// yes, reset the previous key and
                	// set the flag.
                    $key = '';
                    $in_delim = true;
                } else {
                	// no, add to the output as-is
                    $newsrc .= $char;
                }
            }
        }
        
        // replace with changed source text
        $this->_wiki->_source = $newsrc;
        
		
		/*
		// PRIOR VERSION
		// has problems mistaking marked-up numbers for delimited tokens
		
		// creates target tokens, retrieves heading level and text
		$this->entry = array();
		$count = 0;
		
		// loop through all tokens and get headings
		foreach ($this->_wiki->_tokens as $key => $val) {
			
			// only get heading starts of level 2 or deeper
			if ($val[0] == 'heading' &&
				$val[1]['type'] == 'start' &&
				$val[1]['level'] > 1) {
				
				// the level of this header
				$level = $val[1]['level'];
				
				// the text of this header
				$text = $val[1]['text'];
				
				// add a toc-target link to the tokens array
				$token = $this->addToken(
					array(
						'type' => 'target',
						'count' => $count,
						'level' => $level
					)
				);
				
				// put the toc target token in front of the
				// heading-start token
				$start = $delim . $key . $delim;
				$this->_wiki->_source = str_replace($start, $token.$start,
					$this->_wiki->_source);
				
				// retain the toc item
				$this->entry[] = array (
					'count' => $count,
					'level' => $level,
					'text' => $text
				);
				
				// increase the count for the next item
				$count++;
			}
		}
		*/
	}

	
	/**
	* 
	* Renders a token into text matching the requested format.
	* 
	* @access public
	* 
	* @param array $options The "options" portion of the token (second
	* element).
	* 
	* @return string The text rendered from the token options.
	* 
	*/
	
	function renderXhtml($options)
	{
		// type, count, level
		extract($options);
		
		// the prefix used for anchor names
		$prefix = 'toc';
		
		if ($type == 'target') {
			// ... generate an anchor.
			return "<a name=\"$prefix$count\"></a>";
		}
		
		if ($type == 'list_start') {
			return "<p>\n";
		}
		
		if ($type == 'list_end') {
			return "</p>\n";
		}
		
		if ($type == 'item_start') {
			
			// build some indenting spaces for the text
			$indent = ($level - 2) * 4;
			$pad = str_pad('', $indent);
			$pad = str_replace(' ', '&nbsp;', $pad);
			
			// add an extra linebreak in front of heading-2
			// entries (makes for nice section separations)
			if ($level <= 2 && $count > 0) {
				$pad = "<br />\n$pad";
			}
			
			// create the entry line as a link to the toc anchor
			return "$pad<a href=\"#$prefix$count\">";
		}
		
		if ($type == 'item_end') {
			return "</a><br />\n";
		}
	}

}
?>