class CSSCompression_Organize

class CSSCompression_Organize {
    
    /**
     * Organize Patterns
     *
     * @class Control: Compression Controller
     * @param (array) options: Reference to options
     * @param (regex) rsemicolon: Checks for semicolon without an escape '\' character before it
     * @param (regex) rlastsemi: Checks for semicolon at the end of the string
     */
    private $Control;
    private $options = array();
    private $rsemicolon = "/(?<!\\\\);/";
    private $rlastsemi = "/(?<!\\\\);\$/";
    
    /**
     * Stash a reference to the controller on each instantiation
     *
     * @param (class) control: CSSCompression Controller
     */
    public function __construct(CSSCompression_Control $control) {
        $this->Control = $control;
        $this->options =& $control->Option->options;
    }
    
    /**
     * Look to see if we can combine selectors to reduce the number
     * of definitions.
     *
     * @param (array) selectors: Array of selectors, map directly to details
     * @param (array) details: Array of rule sets, map directly to selectors
     */
    public function organize(&$selectors = array(), &$details = array()) {
        // Combining defns based on similar selectors
        list($selectors, $details) = $this->reduceSelectors($selectors, $details);
        // Combining defns based on similar details
        list($selectors, $details) = $this->reduceDetails($selectors, $details);
        // Return in package form
        return array(
            $selectors,
            $details,
        );
    }
    
    /**
     * Combines multiply defined selectors by merging the rule sets,
     * latter declarations overide declaratins at top of file
     *
     * @param (array) selectors: Array of selectors broken down by setup
     * @param (array) details: Array of rule sets broken down by setup
     */
    private function reduceSelectors($selectors, $details) {
        $keys = array_keys($selectors);
        $max = array_pop($keys) + 1;
        for ($i = 0; $i < $max; $i++) {
            if (!isset($selectors[$i])) {
                continue;
            }
            for ($k = $i + 1; $k < $max; $k++) {
                if (!isset($selectors[$k])) {
                    continue;
                }
                if ($selectors[$i] == $selectors[$k]) {
                    // Prevent noticies
                    if (!isset($details[$i])) {
                        $details[$i] = '';
                    }
                    if (!isset($details[$k])) {
                        $details[$k] = '';
                    }
                    // We kill the last semicolon before organization, so account for that.
                    if ($details[$i] != '' && $details[$k] != '' && !preg_match($this->rlastsemi, $details[$i])) {
                        $details[$i] .= ';' . $details[$k];
                    }
                    else {
                        $details[$i] .= $details[$k];
                    }
                    // Remove the second part
                    unset($selectors[$k], $details[$k]);
                }
            }
        }
        return array(
            $selectors,
            $details,
        );
    }
    
    /**
     * Combines multiply defined rule sets by merging the selectors
     * in comma seperated format
     *
     * @param (array) selectors: Array of selectors broken down by setup
     * @param (array) details: Array of rule sets broken down by setup
     */
    private function reduceDetails($selectors, $details) {
        $keys = array_keys($selectors);
        $max = array_pop($keys) + 1;
        for ($i = 0; $i < $max; $i++) {
            if (!isset($selectors[$i])) {
                continue;
            }
            $arr = preg_split($this->rsemicolon, isset($details[$i]) ? $details[$i] : '');
            for ($k = $i + 1; $k < $max; $k++) {
                if (!isset($selectors[$k])) {
                    continue;
                }
                $match = preg_split($this->rsemicolon, isset($details[$k]) ? $details[$k] : '');
                $x = array_diff($arr, $match);
                $y = array_diff($match, $arr);
                if (count($x) < 1 && count($y) < 1) {
                    $selectors[$i] .= ',' . $selectors[$k];
                    unset($details[$k], $selectors[$k]);
                }
            }
        }
        return array(
            $selectors,
            $details,
        );
    }
    
    /**
     * Access to private methods for testing
     *
     * @param (string) method: Method to be called
     * @param (array) args: Array of paramters to be passed in
     */
    public function access($method, $args) {
        if (method_exists($this, $method)) {
            return call_user_func_array(array(
                $this,
                $method,
            ), $args);
        }
        else {
            throw new CSSCompression_Exception("Unknown method in Organize Class - " . $method);
        }
    }

}