<?php
define('__ABSPATH__', dirname(__FILE__).'/');
define('__CSSPATH__', 'css/');
define('__JSPATH__', 'js/' );

class Resources
{
    private $packages = array ( );

    public function __construct ( )
    {
        $xml = simplexml_load_file("package-config.xml");

        foreach ( $xml -> package as $package )
        {
            $files = array ( );

            foreach ( $package -> file as $file )
            {
                $files [ ] = $file [ 'url' ];
            }

            $this -> packages [ (string) $package [ 'type' ] ] [ (string) $package [ 'name' ] ] = array ( "files" => $files );
        }
    }

    public function loadResource ( $key )
    {
        $key_bits = explode ( ".", $key );

        $id = UrlShortener::shortToInt ( $key_bits [ 0 ] );
        $type = $key_bits [ 1 ];

        $query = mysql_query ( "SELECT name, built FROM resources_v2 WHERE id = '$id' AND type = '$type' LIMIT 1" );

        if ( mysql_num_rows ( $query ) > 0 )
        {
            $row = mysql_fetch_assoc ( $query );

            if ( is_array ( $this -> packages [ $type ] [ $row [ 'name' ] ] ) )
            {
                header("Cache-Control: max-age=1209600, must-revalidate");
                //header("Last-Modified: " . gmdate('D, d M Y H:i:s', strtotime ( $row [ 'built' ] ) ) . ' GMT' );
                //header("HTTP/1.1 304 Not Modified");

                $path = $this -> getPath ( $type );

                $content = '';

                foreach ( $this -> packages [ $type ] [ $row [ 'name' ] ] [ 'files' ] as $file )
                {
                    $content .= file_get_contents ( $path . $file ) . "\n";
                }

                switch ( $type )
                {
                    case "js":
                        header ( "content-type: application/javascript" );
                        echo $this -> minifyJS ( $content );
                        break;
                    case "css":
                        header ( "content-type: text/css" );
                        echo $this -> minifyCSS ( $content );
                        break;
                }

                return;
            }
        }

        header ( 'HTTP/1.0 404 Not Found' );
        die ( "404, Not found" );
    }

    public function resourceLink ( $type, $package )
    {
        if ( $this -> isValidPackage ( $type, $package ) === TRUE )
        {
            $path = $this -> getPath ( $type );

            $total = 0;

            foreach ( $this -> packages [ $type ] [ $package ] [ 'files' ] as $file )
            {
                if ( ! file_exists ( $path . $file ) )
                {
                    // File does not exist... return
                    return ( NULL );
                }

                $total += filemtime ( $path . $file );
            }

            if ( ( $data = $this -> resourceRowExists ( $package, $type ) ) !== FALSE )
            {
                if ( $total != $data [ 0 ] [ 'lmodified_total' ] )
                {
                    if ( count ( $data ) > 1 )
                    {
                        $ids = implode(', ', array_map(function ($current) { return $current['id']; }, array_slice ( $data, 1 )));

                        $this -> resourceRowDelete ( $ids );
                    }

                    $this -> resourceRowCreate ( $package, $type, $total );
                }
            }
            else
            {
                $this -> resourceRowCreate ( $package, $type, $total );
            }

            $query = mysql_query ( "SELECT id FROM resources_v2 WHERE name = '$package' AND type = '$type' ORDER BY id DESC LIMIT 1" ) or die ( mysql_error ( ) );

            $row = mysql_fetch_assoc ( $query );

            $key = UrlShortener::intToShort ( $row [ 'id' ] );

            return ( 'rsrc/' . $key . '.' . $type );
        }

        return ( NULL );
    }

    public function css ( $package )
    {
        if ( ( $link = $this -> resourceLink ( "css", $package ) ) != NULL )
        {
            return ( "<link rel=\"stylesheet\" type=\"text/css\" href=\"$link\" />" );
        }

        return ( NULL );
    }

    public function js ( $package )
    {
        if ( ( $link = $this -> resourceLink ( "js", $package ) ) != NULL )
        {
            return ( "<script type=\"text/javascript\" src=\"$link\"></script>" );
        }

        return ( NULL );
    }

    public function minifyCSS ( $css )
    {
        // Compress whitespace.
        $css = preg_replace ( '/\s+/', '', $css );

        // Remove comments.
        $css = preg_replace ( '/\/\*.*?\*\//', '', $css );

        return trim ( $css );
    }

    public function minifyJS ( $js )
    {
        require_once ( "jsmin.php" );

        return ( JSMin :: minify ( $js ) );
    }

    public function getPath ( $type )
    {
        switch ( $type )
        {
            case "css":
                $path = __CSSPATH__;
                break;
            case "js":
                $path = __JSPATH__;
                break;
        }

        return ( $path );
    }

    public function resourceRowDelete ( $ids )
    {
        if ( empty( $ids ) )
        {
            return ( FALSE );
        }

        $query = mysql_query ( "DELETE FROM resources_v2 WHERE id IN($ids)" );
    }

    public function resourceRowCreate ( $package, $type, $total )
    {
        $query = mysql_query ( "INSERT INTO resources_v2 (name, type, lmodified_total, built) VALUES ('$package', '$type', $total, NOW())" ) or die ( mysql_error ( ) );
    }

    // This function does not return true
        // but an array of data
    public function resourceRowExists ( $package, $type )
    {
        $query = mysql_query ( "SELECT id, lmodified_total FROM resources_v2 WHERE name = '$package' AND type = '$type' ORDER BY id DESC" ) or die ( mysql_error ( ) );

        if ( mysql_num_rows ( $query ) > 0 )
        {
            // The newest should be first
            $data = array ( );

            while ( $row = mysql_fetch_assoc ( $query ) )
            {
                $data [ ] = $row;
            }

            return ( $data );
        }
        else
        {
            return ( FALSE );
        }
    }

    public function isValidPackage ( $type, $package )
    {
        if ( isset ( $this -> packages [ $type ] [ $package ] ) && is_array ( $this -> packages [ $type ] [ $package ] ) )
        {
            return ( TRUE );
        }

        return ( FALSE );
    }
}
?>