<?php
/**
 * The concrete command that compiles CSS.
*
* @author     Time.ly Network Inc.
* @since      2.1
*
* @package    AI1EC
* @subpackage AI1EC.Command
*/
class Ai1ec_Command_Compile_Core_Css extends Ai1ec_Command {

    /*
     * (non-PHPdoc) @see Ai1ec_Command::is_this_to_execute()
     */
    public function is_this_to_execute() {
        if ( isset( $_GET['ai1ec_compile_css'] ) &&
            AI1EC_DEBUG
        ) {
            return true;
        }
        return false;
    }

    /* (non-PHPdoc)
     * @see Ai1ec_Command::set_render_strategy()
    */
    public function set_render_strategy( Ai1ec_Request_Parser $request ) {
        $this->_render_strategy = $this->_registry->get(
            'http.response.render.strategy.void'
        );
    }

    /* (non-PHPdoc)
     * @see Ai1ec_Command::do_execute()
    */
    public function do_execute() {
        $message = $this->_process_files();
        echo $message;
        return Ai1ec_Http_Response_Helper::stop( 0 );
    }

    /**
     * Returns calendar theme structure.
     *
     * @param string $stylesheet Calendar stylesheet. Expects one of
     *                           ['vortex','plana','umbra','gamma'].
     * @return array Calendar themes.
     *
     * @throws Ai1ec_Invalid_Argument_Exception
     */
    protected function _get_theme( $stylesheet ) {
        return $this->_registry->get(
            'filesystem.misc'
        )->build_theme_structure( $stylesheet );
    }

    /**
     * Returns PHP code with hashmap array.
     *
     * @param $hashmap Array with compilation hashes.
     *
     * @return string PHP code.
     */
    protected function _get_hashmap_array( $hashmap ) {
        return '<?php return ' . var_export( $hashmap, true ) . ';';
    }

    protected function _process_files() {
        $less   = $frontend = $this->_registry->get( 'less.lessphp' );
        $option = $this->_registry->get( 'model.option' );
        $theme  = $this->_get_theme( $_GET['theme'] );

        if ( isset( $_GET['switch'] ) ) {
            $option->delete( 'ai1ec_less_variables' );
            $option->set( 'ai1ec_current_theme', $theme );
            return 'Theme switched to "' . $theme['stylesheet'] . '".';
        }

        $css      = $less->parse_less_files( null, true );
        $hashmap  = $less->get_less_hashmap();
        $hashmap  = $this->_get_hashmap_array( $hashmap );
        $filename = $theme['theme_dir'] . DIRECTORY_SEPARATOR .
                    'css' . DIRECTORY_SEPARATOR . 'ai1ec_parsed_css.css';
        $hashmap_file = $theme['theme_dir'] . DIRECTORY_SEPARATOR .
                    'less.sha1.map.php';

        $css_written     = file_put_contents( $filename, $css );
        $hashmap_written = file_put_contents( $hashmap_file, $hashmap );
        if (
            false === $css_written ||
            false === $hashmap_written
        ) {
            return 'There has been an error writing theme CSS';
        }

        return 'Theme CSS compiled succesfully and written in ' .
                    $filename . ' and classmap stored in ' . $hashmap_file;
    }
}