<?php
    class TextUtils
    {
	public static function SplitTags($str)
	{
	    $str = str_replace("\\\"", "\"", $str);
	    $tags = array();
	    preg_match_all('/"([a-zA-Z0-9 ]+)"/', $str, $tests);
	    $useful = $tests[1];
	    foreach($useful as $match)
	    {
		$tags[] = $match;
		$str = str_replace("\"{$match}\"", null, $str);
	    }
	    $str = preg_replace("/( )+/", " ", trim($str));
	    if(strlen($str) > 0)
		$tags = array_merge($tags, explode(" ", $str));
	    asort($tags);
	    return $tags;
	}
	
	public static function DiffTagLine($old, $new, &$ajout, &$suppr)
	{
	    $arOld = TextUtils::SplitTags($old);
	    $arNew = TextUtils::SplitTags($new);
	    $ajout = array_diff($arNew, $arOld);
	    $suppr = array_diff($arOld, $arNew);
	}
    }
?>