<?php

/**
* 
* Trim leading white space and blank lines from template source after it
* gets interpreted, cleaning up code and saving bandwidth. Does not
* affect <<PRE>></PRE> and <SCRIPT></SCRIPT> blocks.<br>
* 
* @author Monte Ohrt <hide@address.com>
* 
* @author Contributions from Lars Noschinski <hide@address.com>
* 
* @author Converted to a Savant filter by Paul M. Jones
* <hide@address.com>
* 
* @param object &$savant The calling Savant object.
* 
* @param string &$source The source text to be filtered.
*
* @version $Id: Savant_Filter_trimwhitespace.php,v 1.2 2003/09/24 16:04:55 pmjones Exp $
* 
*/

require_once 'Savant/Filter.php';

class Savant_Filter_trimwhitespace {

	function trimwhitespace(&$savant, &$source)
	{
		// Pull out the script blocks
		preg_match_all("!<script[^>]+>.*?</script>!is", $source, $match);
		$_script_blocks = $match[0];
		$source = preg_replace("!<script[^>]+>.*?</script>!is",
		'@@@SAVANT:TRIM:SCRIPT@@@', $source);
	
		// Pull out the pre blocks
		preg_match_all("!<pre>.*?</pre>!is", $source, $match);
		$_pre_blocks = $match[0];
		$source = preg_replace("!<pre>.*?</pre>!is",
		'@@@SAVANT:TRIM:PRE@@@', $source);
	
		// Pull out the textarea blocks
		preg_match_all("!<textarea[^>]+>.*?</textarea>!is", $source, $match);
		$_textarea_blocks = $match[0];
		$source = preg_replace("!<textarea[^>]+>.*?</textarea>!is",
		'@@@SAVANT:TRIM:TEXTAREA@@@', $source);
	
		// remove all leading spaces, tabs and carriage returns NOT
		// preceeded by a php close tag.
			$source = trim(preg_replace('/((?<!\?>)\n)[\s]+/m', '\1', $source));
	
		// replace script blocks
		Savant_Filter_trimwhitespace::_replace(
			"@@@SAVANT:TRIM:SCRIPT@@@",$_script_blocks, $source);
	
		// replace pre blocks
		Savant_Filter_trimwhitespace::_replace(
			"@@@SAVANT:TRIM:PRE@@@",$_pre_blocks, $source);
	
		// replace textarea blocks
		Savant_Filter_trimwhitespace::_replace(
			"@@@SAVANT:TRIM:TEXTAREA@@@",$_textarea_blocks, $source);
	
		return $source; 
	}

	function _replace($search_str, $replace, &$subject)
	{
		$_len = strlen($search_str);
		$_pos = 0;
		for ($_i=0, $_count=count($replace); $_i<$_count; $_i++) {
			if (($_pos=strpos($subject, $search_str, $_pos))!==false) {
				$subject = substr_replace($subject, $replace[$_i], $_pos, $_len);
			} else {
				break;
			}
		}
	}

}
?>