<?php
/**
 * CSS Parser Helper
 * Based on a class by Michael Ettl (michael@ettl.com)
 */
class AM_RevSlider_Helper_Css extends Mage_Core_Helper_Abstract {
    protected $css;
    protected $cssprops;
    protected $cssstr;

    /**
     * Constructor function for PHP5
     *
     */
    public function __construct(){
        $this->css = array();
        $this->cssprops = array();
        $this->cssstr = '';
    }

    /**
     * Parses an entire CSS file
     *
     * @param mixed $file_name CSS File to parse
     * @return mixed
     */
    public function parse_file($file_name){
        $fh = fopen($file_name, 'r') or die("Error opening file $file_name");
        $css_str = fread($fh, filesize($file_name));
        fclose($fh);
        return ($this->parse_css($css_str));
    }

    /**
     * Parses a CSS string
     *
     * @param string $css_str CSS to parse
     * @return string
     */
    public function parse_css($css_str){
        $this->cssstr = $css_str;
        $this->css = '';
        $this->cssprops = '';

        // Strip all line endings and both single and multiline comments
        $regex = array(
            "`^([\t\s]+)`ism" => '',
            "`^\/\*(.+?)\*\/`ism" => '',
            "`([\n\A;]+)\/\*(.+?)\*\/`ism" => "$1",
            "`([\n\A;\s]+)//(.+?)[\n\r]`ism" => "$1\n",
            "`(^[\r\n]*|[\r\n]+)[\s\t]*[\r\n]+`ism" => "\n"
        );
        $css_str = preg_replace(array_keys($regex), $regex, $css_str);

        $css_class = explode('}', $css_str);

        while (list($key, $val) = each($css_class)){
            $aCSSObj = explode('{', $val);
            //$cSel = strtolower(trim($aCSSObj[0]));
            $cSel = trim($aCSSObj[0]);
            if($cSel){
                $this->cssprops[] = $cSel;
                $a = explode(';', $aCSSObj[1]);
                while(list($key, $val0) = each($a)){
                    if(trim($val0)){
                        $aCSSSub = explode(':', $val0);
                        $cAtt = strtolower(trim($aCSSSub[0]));
                        if(isset($aCSSSub[1])){
                            $aCSSItem[$cAtt] = trim($aCSSSub[1]);
                        }
                    }
                }
                if((isset($this->css[$cSel])) && ($this->css[$cSel])){
                    $aCSSItem = array_merge($this->css[$cSel], $aCSSItem);
                }
                $this->css[$cSel] = $aCSSItem;
                unset($aCSSItem);
            }
            if(strstr($cSel, ',')){
                $aTags = explode(',', $cSel);
                foreach($aTags as $value0){
                    $this->css[$value0] = $this->css[$cSel];
                }
                unset($this->css[$cSel]);
            }
        }
        unset($css_str, $css_class, $aCSSSub, $aCSSItem, $aCSSObj);
        return $this->css;
    }

    /**
     * Builds a CSS string out of an existing object
     *
     * @param boolean $sorted Sort the attributes alphabetically
     * @return string Resulting CSS string
     */
    public function build_css($sorted = false){
        $this->cssstr = '';
        foreach($this->css as $key0 => $value0) {
            $trimmed = trim($key0);
            $this->cssstr .= "$trimmed {\n";
            if($sorted) ksort($this->css[$key0], SORT_STRING);
            foreach($this->css[$key0] as $key1 => $value1) {
                $this->cssstr .= "\t$key1: $value1;\n";
            }
            $this->cssstr .= "}\n";
        }
        return ($this->cssstr);
    }

    /**
     * Writes an existing CSS string to file
     *
     * @param string $file_name File to save to
     * @param boolean $sorted Sort the attributes alphabetically
     */
    public function write_file($file_name, $sorted = false){
        if($this->css == '') die('There is no CSS to write!');
        if($this->cssstr == '') $this->build_css($sorted);
        $fh = fopen($file_name, 'w') or die("Error opening file $file_name");
        fwrite($fh, $this->cssstr);
        fclose($fh);
    }

    /**
     * Returns the entire CSS object
     *
     * @return object or false
     */
    public function get_css(){
        if (isset($this->css)) return ($this->css);
        return false;
    }

    /**
     * Returns all CSS properties
     *
     * @return array
     */
    public function get_properties(){
        if (isset($this->cssprops)) return ($this->cssprops);
        return array();
    }

    /**
     * Returns a specified CSS property and all its attributes
     *
     * @param string $prop
     * @return array
     */
    public function get_property($prop){
        if (isset($this->css[$prop])) return ($this->css[$prop]);
        return array();
    }

    /**
     * Gets attribute value of a specified CSS property
     *
     * @param string $prop CSS property
     * @param string $attr CSS attribute
     * @return string
     */
    public function get_value($prop, $attr){
        if (isset($this->css[$prop][$attr])) return ($this->css[$prop][$attr]);
        return '';
    }

    /**
     * Sets attribute value of a specified CSS property
     *
     * @param string $prop CSS property
     * @param string $attr CSS attribute
     * @param string $value CSS attribute value
     * @return boolean Returns true when succeeded
     */
    public function set_value($prop, $attr, $value){
        if(empty($prop)||empty($attr)) return false;
        $this->css[$prop][$attr] = $value;
        return true;
    }
}