Source for file css_parser.php

<?php
/**
 * CSSTidy - CSS Parser and Optimiser
 *
 * CSS Parser class
 * This class represents a CSS parser which reads CSS code and saves it in an array.
 * In opposite to most other CSS parsers, it does not use regular expressions and
 * thus has full CSS2 support and a higher reliability.
 * Additional to that it applies some optimisations and fixes to the CSS code.
 * An online version should be available here: http://cdburnerxp.se/cssparse/css_optimiser.php
 *
 * This file is part of CSSTidy.
 *
 * CSSTidy is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * CSSTidy is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with CSSTidy; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * @license http://opensource.org/licenses/gpl-license.php GNU Public License
 * @package csstidy
 * @author Florian Schmitz (floele at gmail dot com) 2005
 */
 
/**
 * Various CSS data needed for correct optimisations etc.
 *
 * @version 1.2
 */
require('data.inc.php');
 
/**
 * All functions which are not directly related to the parser class
 *
 * Not required. If this file is not included, csstidy does without these functions.
 * @version 1.2
 */
@include('functions.inc.php');
 
/**
 * CSS Parser class
 *
 * This class represents a CSS parser which reads CSS code and saves it in an array.
 * In opposite to most other CSS parsers, it does not use regular expressions and
 * thus has full CSS2 support and a higher reliability.
 * Additional to that it applies some optimisations and fixes to the CSS code.
 * An online version should be available here: http://cdburnerxp.se/cssparse/css_optimiser.php
 * @package csstidy
 * @author Florian Schmitz (floele at gmail dot com) 2005
 * @version 1.1
 */
class csstidy {
 
/**
 * Saves the parsed CSS
 * @var array 
 * @access public
 */
var $css = array();
 
/**
 * Saves the CSS charset (@charset)
 * @var string 
 * @access private
 */
var $charset = '';
 
/**
 * Saves all @import URLs
 * @var array 
 * @access private
 */
var $import = array();
 
/**
 * Saves the namespace
 * @var string 
 * @access private
 */
var $namespace = '';
 
/**
 * Saves the input CSS string
 * @var string 
 * @access private
 */
var $input_css = '';
 
/**
 * Saves the formatted CSS string
 * @var string 
 * @access public
 */
var $output_css = '';
 
/**
 * Saves the formatted CSS string (plain text)
 * @var string 
 * @access public
 */
var $output_css_plain = '';
 
/**
 * Saves the templates
 * @var array 
 * @access private
 * @see http://cdburnerxp.se/cssparse/template.htm
 */
var $template = array();
 
/**
 * Contains the version of csstidy
 * @var string 
 * @access private
 */
var $version = '1.1';
 
/**
 * Stores comments
 * @var array 
 * @access private
 */
var $comments = array();
 
/**
 * Stores the settings
 * @var array 
 * @access private
 */
var $settings = array();
 
/**
 * Saves the parser-status.
 *
 * Possible values:
 * - is = in selector
 * - ip = in property
 * - iv = in value
 * - instr = in string (started at " or ' or ( )
 * - ic = in comment (ignore everything)
 * - at = in @-block
 * 
 * @var string 
 * @access private
 */
var $status = 'is';
 
 
/**
 * Saves the current at rule (@media)
 * @var string 
 * @access private
 */
var $at = '';
 
/**
 * Saves the current selector
 * @var string 
 * @access private
 */
var $selector = '';
 
/**
 * Saves the current property
 * @var string 
 * @access private
 */
var $property = '';
 
/**
 * Saves the position of , in selectors
 * @var array 
 * @access private
 */
var $sel_seperate = array();
 
/**
 * Saves the current value
 * @var string 
 * @access private
 */
var $value = '';
 
/**
 * Saves the current sub-value
 *
 * Example for a subvalue:
 * background:url(foo.png) red no-repeat;
 * "url(foo.png)", "red", and  "no-repeat" are subvalues,
 * seperated by whitespace
 * @var string 
 * @access private
 */
var $sub_value = '';
 
/**
 * Array which saves all subvalues for a property.
 * @var array 
 * @see sub_value
 * @access private
 */
var $sub_value_arr = array();
 
/**
 * Saves the char which opened the last string
 * @var string 
 * @access private
 */
var $str_char = '';
 
/**
 * Status where the string has been started (is or iv)
 * @var string 
 * @access private
 */
var $str_from = '';
 
/**
 * Variable needed to manage string-in-strings, for example url("foo.png")
 * @var string 
 * @access private
 */
var $str_in_str = false;
 
/**
 * =true if in invalid at-rule
 * @var bool 
 * @access private
 */
var $invalid_at = false;
 
/**
 * =true if something has been added to the current selector
 * @var bool 
 * @access private
 */
var $added = false;
 
/**
 * Status where the comment has been started
 * @var string 
 * @access private
 */
var $comment_from = '';
 
/**
 * Array which saves the message log
 * @var array 
 * @access private
 */
var $log = array();
 
/**
 * Saves the line number
 * @var integer 
 * @access private
 */
var $line = 1;
 
/**
 * Loads standard template and sets default settings
 * @access private
 * @version 1.1
 */
function csstidy()
{    
    $this->settings['remove_bslash'] = true;
    $this->settings['compress_colors'] = true;
    $this->settings['compress_font-weight'] = true;
    $this->settings['lowercase_s'] = false;
    $this->settings['save_ie_hacks'] = false;
    $this->settings['optimise_shorthands'] = true;
    $this->settings['only_safe_optimisations'] = true;
    $this->settings['remove_last_;'] = false;
    $this->settings['uppercase_properties'] = false;
    $this->settings['sort_properties'] = false;
    $this->settings['sort_selectors'] = false;
    $this->settings['merge_selectors'] = 2;
    $this->settings['discard_invalid_properties'] = false;
    $this->settings['save_comments'] = false;
    $this->settings['css_level'] = 'CSS2.1';
 
    $this->load_template('default');
}
 
/**
 * Get the value of a setting.
 * @param string $setting 
 * @access public
 * @return mixed 
 * @version 1.0
 */
function get_cfg($setting)
{
    if(isset($this->settings[$setting]))
    {
        return $this->settings[$setting];
    }
    return false;
}
 
/**
 * Set the value of a setting.
 * @param string $setting 
 * @param mixed $value 
 * @access public
 * @return bool 
 * @version 1.0
 */
function set_cfg($setting,$value)
{
    if(isset($this->settings[$setting]) && $value !== '')
    {
        $this->settings[$setting] = $value;
        return true;
    }
    return false;
}
 
/**
 * Add a message to the message log
 * @param string $message 
 * @param string $type 
 * @param integer $line 
 * @access private
 * @version 1.0
 */
function log($message,$type,$line = -1)
{
    if($line === -1)
    {
        $line = $this->line;
    }
    $line = intval($line);
    $add = array('m' => $message, 't' => $type);
    if(!isset($this->log[$line]) || !in_array($add,$this->log[$line]))
    {
        $this->log[$line][] = $add;
    }
}
 
/**
 * Parse unicode notations and find a replacement character
 * @param string $string 
 * @param integer $i 
 * @access private
 * @return string 
 * @version 1.2
 */
function unicode(&$string,&$i)
{
    ++$i;
    $add = '';
    $tokens =& $GLOBALS['csstidy']['tokens'];
    $replaced = false;
    
    while($i < strlen($string) && (ctype_xdigit($string{$i}) || ctype_space($string{$i})) && strlen($add) < 6)
    {
        $add .= $string{$i};
 
        if(ctype_space($string{$i}))
        {
            break;
        }
        $i++;
    }
 
    if(hexdec($add) > 47 && hexdec($add) < 58 || hexdec($add) > 64 && hexdec($add) < 91 || hexdec($add) > 96 && hexdec($add) < 123)
    {
        $this->log('Replaced unicode notation: Changed \\'.$add.' to '.chr(hexdec($add)),'Information');
        $add = chr(hexdec($add));
        $replaced = true;
    }
    else
    {
        $add = trim('\\'.$add);
    }
 
    if(@ctype_xdigit($string{$i+1}) && ctype_space($string{$i}) && !$replaced || !ctype_space($string{$i}))
    {
        $i--;
    }
    
    if($add != '\\' || !$this->get_cfg('remove_bslash') || strpos($tokens, $string{$i+1}) !== false)
    {
        return $add;
    }
    
    if($add == '\\')
    {
        $this->log('Removed unnecessary backslash','Information');
    }
    return '';
}
 
/**
 * Compresses shorthand values. Example: margin:1px 1px 1px 1px -> margin:1px
 * @param string $value 
 * @access private
 * @return string 
 * @version 1.0
 */
function shorthand($value)
{
    $important = '';
    if(csstidy::is_important($value))
    {
        $values = csstidy::gvw_important($value);
        $important = ' !important';
    }
    else $values = $value;
    
    $values = explode(' ',$values);
    switch(count($values))
    {
        case 4:
        if($values[0] == $values[1] && $values[0] == $values[2] && $values[0] == $values[3])
        {
            return $values[0].$important;
        }
        elseif($values[1] == $values[3] && $values[0] == $values[2])
        {
            return $values[0].' '.$values[1].$important;
        }
        elseif($values[1] == $values[3])
        {
            return $values[0].' '.$values[1].' '.$values[2].$important;
        }
        break;
        
        case 3:
        if($values[0] == $values[1] && $values[0] == $values[2])
        {
            return $values[0].$important;
        }
        elseif($values[0] == $values[2])
        {
            return $values[0].' '.$values[1].$important;
        }
        break;
        
        case 2:
        if($values[0] == $values[1])
        {
            return $values[0].$important;
        }
        break;
    }
    
    return $value;
}
 
/**
 * Get compression ratio and prints the code if necessary.
 * @access public
 * @return float 
 * @version 1.1
 */
function get_ratio()
{
    if(empty($this->output_css_plain))
    {
        $this->print_code($this->css);
    }
    return $ratio = round(((strlen($this->input_css))-(strlen($this->output_css_plain)))/(strlen($this->input_css)),3)*100;
}
 
/**
 * Get difference between the old and new code in bytes and prints the code if necessary.
 * @access public
 * @return string 
 * @version 1.1
 */
function get_diff()
{
    if(empty($this->output_css_plain))
    {
        $this->print_code($this->css);
    }
    $diff = (strlen($this->output_css_plain))-(strlen($this->input_css));
    
    if($diff > 0)
    {
        return '+'.$diff;
    }
    elseif($diff == 0)
    {
        return '+-'.$diff;
    }
    else
    {
        return $diff;
    }
}
 
/**
 * Get the size of either input or output CSS in KB
 * @param string $loc default is "output"
 * @access public
 * @return integer 
 * @version 1.0
 */
function size($loc = 'output')
{
    if($loc == 'output' && empty($this->output_css))
    {
        $this->print_code($this->css);
    }
    
    if($loc == 'input')
    {
        return (strlen($this->input_css)/1000);
    }
    else
    {
        return (strlen(html_entity_decode(strip_tags($this->output_css)))/1000);
    }
}
 
/**
 * Loads a new template
 * @param string $content either filename (if $from_file == true), content of a template file, "high_compression", "highest_compression", "low_compression", or "default"
 * @param bool $from_file uses $content as filename if true
 * @access public
 * @version 1.1
 * @see http://csstidy.sourceforge.net/templates.php
 */
function load_template($content,$from_file=true)
{
    $predefined_templates =& $GLOBALS['csstidy']['predefined_templates'];
    if($content == 'high_compression' || $content == 'default' || $content == 'highest_compression' || $content == 'low_compression')
    {
        $this->template = $predefined_templates[$content];
        return;
    }
    
    if($from_file)
    {
        $content = strip_tags(file_get_contents($content),'<span>');
    }
    $content = str_replace("\r\n","\n",$content); // Unify newlines (because the output also only uses \n)
    $template = explode('|',$content);
 
    for ($i = 0; $i < count($template); $i++ )
    {
        $this->template[$i] = $template[$i];
    }
}
 
/**
 * Starts parsing from URL
 * @param string $url 
 * @access public
 * @version 1.0
 */
function parse_from_url($url)
{
    $content = @file_get_contents($url);
    return $this->parse($content);
}
 
/**
 * Checks if there is a token at the current position
 * @param string $string 
 * @param integer $i 
 * @access public
 * @version 1.1
 */
function is_token(&$string,$i)
{
    $tokens =& $GLOBALS['csstidy']['tokens'];
    return (strpos($tokens, $string{$i}) !== false && !csstidy::escaped($string,$i));
}
 
 
/**
 * Parses CSS in $string. The code is saved as array in $this->css
 * @param string $string the CSS code
 * @access public
 * @return bool 
 * @version 1.1
 */
function parse($string) {
 
$shorthands =& $GLOBALS['csstidy']['shorthands'];
$all_properties =& $GLOBALS['csstidy']['all_properties'];
$at_rules =& $GLOBALS['csstidy']['at_rules'];
 
$this->css = array();
$this->input_css = $string;
$string = str_replace("\r\n","\n",$string) . ' ';
$cur_comment = '';
 
for ($i = 0, $size = strlen($string); $i < $size; $i++ )
{
    if($string{$i} == "\n" || $string{$i} == "\r")
    {
        ++$this->line;
    }
    
    switch($this->status)
    {
        /* Case in at-block */
        case 'at':
        if(csstidy::is_token($string,$i))
        {
            if($string{$i} == '/' && @$string{$i+1} == '*')
            {
                $this->status = 'ic'; ++$i;
                $this->comment_from = 'at';
            }
            elseif($string{$i} == '{')
            {
                $this->status = 'is';
            }
            elseif($string{$i} == ',')
            {
                $this->at = trim($this->at).',';
            }
            elseif($string{$i} == '\\')
            {
                $this->at .= $this->unicode($string,$i);
            }
        }
        else
        {
            $lastpos = strlen($this->at)-1;
            if(!( (ctype_space($this->at{$lastpos}) || csstidy::is_token($this->at,$lastpos) && $this->at{$lastpos} == ',') && ctype_space($string{$i})))
            {
                $this->at .= $string{$i};
            }
        }
        break;
        
        /* Case in-selector */
        case 'is':
        if(csstidy::is_token($string,$i))
        {
            if($string{$i} == '/' && @$string{$i+1} == '*' && trim($this->selector) == '')
            {
                $this->status = 'ic'; ++$i;
                $this->comment_from = 'is';
            }
            elseif($string{$i} == '@' && trim($this->selector) == '')
            {
                // Check for at-rule
                $this->invalid_at = true;
                foreach($at_rules as $name => $type)
                {
                    if(!strcasecmp(substr($string,$i+1,strlen($name)),$name))
                    {
                        ($type == 'at') ? $this->at = '@'.$name : $this->selector = '@'.$name;
                        $this->status = $type;
                        $i += strlen($name);
                        $this->invalid_at = false;
                    }
                }
                        
                if($this->invalid_at)
                {
                    $this->selector = '@'.$this->selector;
                    $invalid_at_name = '';
                    for($j = $i+1; $j < $size; ++$j)
                    {
                        if(!ctype_alpha($string{$j}))
                        {
                            break;
                        }
                        $invalid_at_name .= $string{$j};
                    }
                    $this->log('Invalid @-rule: '.$invalid_at_name.' (removed)','Warning');
                }
            }
            elseif(($string{$i} == '"' || $string{$i} == "'"))
            {
                $this->selector .= $string{$i};
                $this->status = 'instr';
                $this->str_char = $string{$i};
                $this->str_from = 'is';
            }
            elseif($this->invalid_at && $string{$i} == ';')
            {
                $this->invalid_at = false;
                $this->status = 'is';
            }
            elseif($string{$i} == '{')
            {
                $this->status = 'ip';
                $this->added = false;
            }
            elseif($string{$i} == '}')
            {
                $this->at = '';
                $this->selector = '';
                $this->sel_seperate = array();
            }
            elseif($string{$i} == ',') 
            {
                $this->selector = trim($this->selector).',';
                $this->sel_seperate[] = strlen($this->selector);
            }
            elseif($string{$i} == '\\')
            {
                $this->selector .= $this->unicode($string,$i);
            }
            else $this->selector .= $string{$i};
        }
        else
        {
            $lastpos = strlen($this->selector)-1;
            if($lastpos == -1 || !( (ctype_space($this->selector{$lastpos}) || csstidy::is_token($this->selector,$lastpos) && $this->selector{$lastpos} == ',') && ctype_space($string{$i})))
            {
                $this->selector .= $string{$i};
            }
        }
        break;
        
        /* Case in-property */
        case 'ip':
        if(csstidy::is_token($string,$i))
        {
            if(($string{$i} == ':' || $string{$i} == '=') && $this->property != '')
            {
                $this->status = 'iv';
            }
            elseif($string{$i} == '/' && @$string{$i+1} == '*' && $this->property == '')
            {
                $this->status = 'ic'; ++$i;
                $this->comment_from = 'ip';
            }
            elseif($string{$i} == '}')
            {
                $this->explode_selectors();
                $this->status = 'is';
                $this->invalid_at = false;
                if($this->selector{0} != '@' && !$this->added)
                {
                    $this->log('Removed empty selector: '.trim($this->selector),'Information');
                }
                $this->selector = '';
                $this->property = '';
            }
            elseif($string{$i} == ';')
            {
                $this->property = '';
            }
            elseif($string{$i} == '\\')
            {
                $this->property .= $this->unicode($string,$i);
            }
        }
        elseif(!ctype_space($string{$i}))
        {
            $this->property .= $string{$i};
        }
        break;
        
        /* Case in-value */
        case 'iv':
        $pn = (ctype_space($string{$i}) && $this->property_is_next($string,$i+1) || $i == strlen($string)-1);
        if(csstidy::is_token($string,$i) || $pn)
        {
            if($string{$i} == '/' && @$string{$i+1} == '*')
            {
                $this->status = 'ic'; ++$i;
                $this->comment_from = 'iv';
            }
            elseif(($string{$i} == '"' || $string{$i} == "'" || $string{$i} == '('))
            {
                $this->sub_value .= $string{$i};
                $this->str_char = ($string{$i} == '(') ? ')' : $string{$i};
                $this->status = 'instr';
                $this->str_from = 'iv';
            }
            elseif($string{$i} == ',')
            {
                $this->sub_value = trim($this->sub_value).',';
            }
            elseif($string{$i} == '\\')
            {
                $this->sub_value .= $this->unicode($string,$i);
            }
            elseif($string{$i} == ';' || $pn)
            {
                if($this->selector{0} == '@' && isset($at_rules[substr($this->selector,1)]) && $at_rules[substr($this->selector,1)] == 'iv')
                {
                    $this->sub_value_arr[] = trim($this->sub_value);
                    
                    $this->status = 'is';
                    
                    switch($this->selector)
                    {
                        case '@charset': $this->charset = $this->sub_value_arr[0]; break;
                        case '@namespace': $this->namespace = implode(' ',$this->sub_value_arr); break;
                        case '@import': $this->import[] = implode(' ',$this->sub_value_arr); break;
                    }
    
                    $this->sub_value_arr = array();
                    $this->sub_value = '';
                    $this->selector = '';
                    $this->sel_seperate = array();
                }
                else
                {
                    $this->status = 'ip';
                }
            }
            elseif($string{$i} != '}')
            {
                $this->sub_value .= $string{$i};
            }
            if(($string{$i} == '}' || $string{$i} == ';' || $pn) && !empty($this->selector))
            {
                if($this->at == '')
                {
                    $this->at = 'standard';
                }
                
                // case settings
                if($this->get_cfg('lowercase_s'))
                {
                    $this->selector = strtolower($this->selector);
                }
                $this->property = strtolower($this->property);
                
                $this->optimise_add_subvalue();
                    
                $this->value = implode(' ',$this->sub_value_arr);
            
                $this->selector = trim($this->selector);
                
                // Remove whitespace at ! important
                if($this->value != $this->c_important($this->value))
                {
                    $this->log('Optimised !important','Information');
                }
                
                // optimise shorthand properties
                if(isset($shorthands[$this->property]))
                {
                    $temp = csstidy::shorthand($this->value);
                    if($temp != $this->value)
                    {
                        $this->log('Optimised shorthand notation ('.$this->property.'): Changed "'.$this->value.'" to "'.$temp.'"','Information');
                    }
                    $this->value = $temp;
                }
                
                // Compress font-weight
                if($this->property == 'font-weight' && $this->get_cfg('compress_font-weight'))
                {
                    $this->c_font_weight($this->value);
                }
 
                $valid = (isset($all_properties[$this->property]) && strpos($all_properties[$this->property],strtoupper($this->get_cfg('css_level'))) !== false );
                if(!$this->invalid_at && trim($this->value) !== '' && (!$this->get_cfg('discard_invalid_properties') || $valid))
                {
                    $this->css_add_property($this->at,$this->selector,$this->property,$this->value);
                
                    // Further Optimisation
                    if($this->property === 'background' && $this->get_cfg('optimise_shorthands') && function_exists('dissolve_short_bg') && !$this->get_cfg('only_safe_optimisations'))
                    {
                        unset($this->css[$this->at][$this->selector]['background']);
                        $this->merge_css_blocks($this->at,$this->selector,dissolve_short_bg($this->value));
                    }
                    if(isset($shorthands[$this->property]) && $this->get_cfg('optimise_shorthands') && function_exists('dissolve_4value_shorthands'))
                    {
                        $this->merge_css_blocks($this->at,$this->selector,dissolve_4value_shorthands($this->property,$this->value));
                        if(is_array($shorthands[$this->property]))
                        {
                            unset($this->css[$this->at][$this->selector][$this->property]);
                        }
                    }
                }
                if(!$valid)
                {
                    if($this->get_cfg('discard_invalid_properties'))
                    {
                        $this->log('Removed invalid property: '.$this->property,'Warning');
                    }
                    else
                    {
                        $this->log('Invalid property in '.strtoupper($this->get_cfg('css_level')).': '.$this->property,'Warning');
                    }
                }
                                    
                $this->property = '';
                $this->sub_value_arr = array();
                $this->value = '';
                if($this->get_cfg('save_comments') && $cur_comment != '')
                {
                    $this->comments[$this->at.$this->selector] = rtrim($cur_comment,"\n\r");
                    $cur_comment = '';
                }
            }
            if($string{$i} == '}')
            {
                $this->explode_selectors();
                $this->status = 'is';
                if($this->selector{0} != '@' && !$this->added)
                {
                    $this->log('Removed empty selector: '.trim($this->selector),'Information');
                }
                $this->invalid_at = false;
                $this->selector = '';
            }    
        }
        elseif(!$pn)
        {
            $this->sub_value .= $string{$i};
 
            if(ctype_space($string{$i}))
            {
                $this->optimise_add_subvalue();
            }
        }
        break;
        
        /* Case in string */
        case 'instr':
        if($this->str_char == ')' && $string{$i} == '"' && !$this->str_in_str && !csstidy::escaped($string,$i))
        {
            $this->str_in_str = true;
        }
        elseif($this->str_char == ')' && $string{$i} == '"' && $this->str_in_str && !csstidy::escaped($string,$i))
        {
            $this->str_in_str = false;
        }
        if($string{$i} == $this->str_char && !csstidy::escaped($string,$i) && !$this->str_in_str)
        {
            $this->status = $this->str_from;
        }
        $temp_add = $string{$i};
                                                            // ...and no not-escaped backslash at the previous position
        if( ($string{$i} == "\n" || $string{$i} == "\r") && !($string{$i-1} == '\\' && !csstidy::escaped($string,$i-1)) )
        {
            $temp_add = "\\A ";
            $this->log('Fixed incorrect newline in string','Warning');
        }
        if($this->str_from == 'iv')
        {
            $this->sub_value .= $temp_add;
        }
        elseif($this->str_from == 'is')
        {
            $this->selector .= $temp_add;
        }
        break;
        
        /* Case in-comment */
        case 'ic':
        if($string{$i} == '*' && $string{$i+1} == '/')
        {
            $this->status = $this->comment_from;
            if($this->comment_from == 'is') $cur_comment .= $this->template[15];
            $i++;
        }
        elseif($this->comment_from == 'is' && $this->get_cfg('save_comments'))
        {
            $cur_comment .= $string{$i};
        }
        break;
    }
}
  
if($this->get_cfg('merge_selectors') == 2)
{
    foreach($this->css as $medium => $value)
    {
        csstidy::merge_selectors($this->css[$medium]);
    }
}
 
if($this->get_cfg('optimise_shorthands'))
{
    foreach($this->css as $medium => $value)
    {
        foreach($value as $selector => $value1)
        {
            if(function_exists('merge_4value_shorthands')) $this->css[$medium][$selector] = merge_4value_shorthands($this->css[$medium][$selector]);
            if(function_exists('merge_bg') && !$this->get_cfg('only_safe_optimisations')) $this->css[$medium][$selector] = merge_bg($this->css[$medium][$selector]);
            if(empty($this->css[$medium][$selector]))
            {
                unset($this->css[$medium][$selector]);
            }
        }
    }
}
 
return (empty($this->css) && empty($this->import) && empty($this->charset) && empty($this->namespace)) ? false : true;
}
 
/**
 * Explodes selectors
 * @access private
 * @version 1.0
 */
function explode_selectors()
{
    // Explode multiple selectors
    if($this->get_cfg('merge_selectors') == 1)
    {
        $new_sels = array();
        $lastpos = 0;
        $this->sel_seperate[] = strlen($this->selector);
        foreach($this->sel_seperate as $num => $pos)
        {
            if($num == count($this->sel_seperate)-1) {
                $pos += 1;
            }
            
            $new_sels[] = substr($this->selector,$lastpos,$pos-$lastpos-1);
            $lastpos = $pos;
        }
 
        if(count($new_sels) > 1)
        {
            foreach($new_sels as $selector)
            {
                $this->merge_css_blocks($this->at,$selector,$this->css[$this->at][$this->selector]);
            }
            unset($this->css[$this->at][$this->selector]);
        }
    }
    $this->sel_seperate = array();
}
 
/**
 * Optimises a sub-value and adds it to sub_value_arr
 * @access private
 * @version 1.0
 */
function optimise_add_subvalue()
{
    $replace_colors =& $GLOBALS['csstidy']['replace_colors'];
    $this->sub_value = trim($this->sub_value);
    if($this->sub_value != '')
    {
        if(function_exists('compress_numbers'))
        {
            $temp = compress_numbers($this->sub_value,$this->property);
            if($temp != $this->sub_value)
            {
                if(strlen($temp) > strlen($this->sub_value))
                {
                    $this->log('Fixed invalid number: Changed "'.$this->sub_value.'" to "'.$temp.'"','Warning');
                }
                else
                $this->log('Optimised number: Changed "'.$this->sub_value.'" to "'.$temp.'"','Information');
                $this->sub_value = $temp;
            }
        }
        if($this->get_cfg('compress_colors') && function_exists('cut_color'))
        {
            $temp = cut_color($this->sub_value);
            if($temp != $this->sub_value)
            {
                if(isset($replace_colors[$this->sub_value]))
                {
                    $this->log('Fixed invalid color name: Changed "'.$this->sub_value.'" to "'.$temp.'"','Warning');
                }
                else
                $this->log('Optimised color: Changed "'.$this->sub_value.'" to "'.$temp.'"','Information');
                $this->sub_value = $temp;
            }
        }
        $this->sub_value_arr[] = $this->sub_value;
        $this->sub_value = '';
    }
}
 
/**
 * Checks if a character is escaped (and returns true if it is)
 * @param string $string 
 * @param integer $pos 
 * @access public
 * @return bool 
 * @version 1.01
 */
function escaped(&$string,$pos) 
{
    return !(@($string{$pos-1} != '\\') || csstidy::escaped($string,$pos-1));
}
 
/**
 * Adds a property with value to the existing CSS code
 * @param string $media 
 * @param string $selector 
 * @param string $property 
 * @param string $new_val 
 * @param bool $ie if $ie == false IE Hacks are not saved even if it is enabled in settings
 * @access private
 * @version 1.1
 */
function css_add_property($media,$selector,$property,$new_val,$ie=true)
{
    $whitespace =& $GLOBALS['csstidy']['whitespace'];
    if($this->get_cfg('save_ie_hacks') && $ie)
    {
        if(isset($this->css[$media][$selector][$property]) && csstidy::is_important($this->css[$media][$selector][$property])
        &&  substr(str_replace($whitespace,'',$selector),0,5) !== '*html')
        {
            $this->log('Converted !important-hack in selector "'.$this->selector.'"','Information');
            if(substr(str_replace($whitespace,'',$selector),0,4) == 'html')
            {
                $this->css_add_property($media,'* '.$selector,$property,$new_val.' !important',false);
            }
            else
            {
                $this->css_add_property($media,'* html '.$selector,$property,$new_val.' !important',false);
            }
        }
        else
        {
            $this->css_add_property($media,$selector,$property,$new_val,false);
        }
    }
    else
    {
        $this->added = true;
        if(isset($this->css[$media][$selector][$property]))
        {
            if((csstidy::is_important($this->css[$media][$selector][$property]) && csstidy::is_important($new_val)) || !csstidy::is_important($this->css[$media][$selector][$property]))
            {
                unset($this->css[$media][$selector][$property]);
                $this->css[$media][$selector][$property] = trim($new_val);
            }
        }
        else
        {
            $this->css[$media][$selector][$property] = trim($new_val);
        }
    }
}
 
/**
 * Adds CSS to an existing media/selector
 * @param string $media 
 * @param string $selector 
 * @param array $css_add 
 * @access private
 * @version 1.1
 */
function merge_css_blocks($media,$selector,$css_add)
{
    foreach($css_add as $property => $value)
    {
        $this->css_add_property($media,$selector,$property,$value,false);
    }
}
 
/**
 * Merges selectors with same properties. Example: a{color:red} b{color:red} -> a,b{color:red}
 * Very basic and has at least one bug. Hopefully there is a replacement soon.
 * @param array $array 
 * @return array 
 * @access public
 * @version 1.2
 */
function merge_selectors(&$array)
{
    $css = $array;
    foreach($css as $key => $value)
    {
        if(!isset($css[$key]))
        {
            continue;
        }
        $newsel = '';
        
        // Check if properties also exist in another selector
        $keys = array();
        // PHP bug (?) without $css = $array; here
        foreach($css as $selector => $vali)
        {
            if($selector == $key)
            {
                continue;
            }
            
            if($css[$key] === $vali)
            {
                $keys[] = $selector;
            }
        }
 
        if(!empty($keys))
        {
            $newsel = $key;
            unset($css[$key]);
            foreach($keys as $selector)
            {
                unset($css[$selector]);
                $newsel .= ','.$selector;
            }
            $css[$newsel] = $value;
        }
    }
    $array = $css;
}
 
 
/**
 * Checks if $value is !important.
 * @param string $value 
 * @return bool 
 * @access public
 * @version 1.0
 */
function is_important(&$value)
{
    $whitespace =& $GLOBALS['csstidy']['whitespace'];
    if(!strcasecmp(substr(str_replace($whitespace,'',$value),-10,10),'!important'))
    {
        return true;
    }
    return false;
}
 
/**
 * Returns a value without !important
 * @param string $value 
 * @return string 
 * @access public
 * @version 1.0
 */
function gvw_important($value)
{
    if(csstidy::is_important($value))
    {
        $value = trim($value);
        $value = substr($value,0,-9);
        $value = trim($value);
        $value = substr($value,0,-1);
        $value = trim($value);
        return $value;
    }
    return $value;
}
 
/**
 * Removes unnecessary whitespace in ! important
 * @param string $string 
 * @return string 
 * @access public
 * @version 1.1
 */
function c_important(&$string)
{
    if(csstidy::is_important($string))
    {
        $string = csstidy::gvw_important($string) . ' !important';
    }
    return $string;
}
 
/**
 * Same as htmlspecialchars, only that chars are not replaced if $plain !== true. This makes  print_code() cleaner.
 * @param string $string 
 * @param bool $plain 
 * @return string 
 * @see csstidy::print_code()
 * @access public
 * @version 1.0
 */
function htmlsp($string, $plain)
{
    if($plain !== true)
    {
        return htmlspecialchars($string);
    }
    return $string;
}
 
/**
 * Returns the formatted CSS Code and saves it into $this->output_css
 * @param array $css 
 * @return string 
 * @access public
 * @version 1.3
 */
function print_code($css = NULL,$plain = false)
{
    $output = '';
    if($css === NULL)
    {
        $css =& $this->css;
    }
    
    $template = $this->template;
 
    if($plain)
    {
        $template = array_map("strip_tags", $template);
    }
    
    if(!empty($this->charset))
    {
        $output .= $template[0].'@charset '.$template[5].$this->charset.$template[6].$template[12];
    }
    
    if(!empty($this->import))
    {
        for ($i = 0, $size = count($this->import); $i < $size; $i ++) {
            $output .= $template[0].'@import '.$template[5].$this->import[$i].$template[6].$template[12];
        }
    }
    
    if(!empty($this->namespace))
    {
        $output .= $template[0].'@namespace '.$template[5].$this->namespace.$template[6].$template[12];
    }
    
    ksort($css);
    
    foreach($css as $medium => $val)
    {
        if ($medium !== 'standard')
        {
            $output .= $template[0].csstidy::htmlsp($medium,$plain).$template[1];
        }
        
        if ($this->get_cfg('sort_selectors')) ksort($val);
 
        foreach($val as $selector => $vali)
        {
            if ($this->get_cfg('sort_properties')) ksort($vali);
            
            if ($medium !== 'standard') $output .= $template[10];
            
            if(isset($this->comments[$medium.$selector]))
            {
                $output .= $template[13].'/*'.$this->comments[$medium.$selector].'*/'.$template[14];
            }
            $output .= ($selector{0} !== '@') ? $template[2].csstidy::htmlsp($selector,$plain) : $template[0].csstidy::htmlsp($selector,$plain);
            $output .= ($medium !== 'standard') ? $template[11] : $template[3];
            
            $i = 0; foreach($vali as $property => $valj)
            {
                $i++;
                if ($medium !== 'standard') $output .= $template[10];
                
                $output .= $template[4];
                $output .= ($this->get_cfg('uppercase_properties')) ? csstidy::htmlsp(strtoupper($property),$plain) : csstidy::htmlsp($property,$plain);
                $output .= ':'.$template[5].csstidy::htmlsp($valj,$plain);
                $output .= ($this->get_cfg('remove_last_;') && $i === count($vali)) ? str_replace(';','',$template[6]) : $template[6];
            }
            
            if ($medium !== 'standard') $output .= $template[10];
            $output .= $template[7];
            if (( end($val) !== $vali && $medium !== 'standard') || $medium === 'standard') $output .= $template[8];
        }
        if ($medium != 'standard') $output .= $template[9];
    }
 
    $output = trim($output);
    
    if($plain !== true)
    {
        $this->output_css = $output;
        $this->print_code($css, true);
    }
    else
    {
        $this->output_css_plain = $output;
    }
    return $output;
}
 
/**
 * Checks if the next word in a string from pos is a CSS property
 * @param string $istring 
 * @param integer $pos 
 * @return bool 
 * @access private
 * @version 1.2
 */
function property_is_next($istring, $pos)
{
    $all_properties =& $GLOBALS['csstidy']['all_properties'];
    $istring = substr($istring,$pos,strlen($istring)-$pos);
    $pos = strpos($istring,':');
    if($pos === false)
    {
        return false;
    }
    $istring = strtolower(trim(substr($istring,0,$pos)));
    if(isset($all_properties[$istring]))
    {
        $this->log('Added semicolon to the end of declaration','Warning');
        return true;
    }
    return false;
}
 
/**
 * Compresses font-weight (not very effective but anyway :-p )
 * @param string $value 
 * @access private
 * @return bool 
 * @version 1.1
 */
function c_font_weight(&$value)
{
    $important = '';
    if(csstidy::is_important($value))
    {
        $important = ' !important';
        $value = csstidy::gvw_important($value);
    }
    if($value == 'bold')
    {
        $value = '700'.$important;
        $this->log('Optimised font-weight: Changed "bold" to "700"','Information');
    }
    else if($value == 'normal')
    {
        $value = '400'.$important;
        $this->log('Optimised font-weight: Changed "normal" to "400"','Information');
    }
}
 
}
?>