<?php

// This file is part of Moodle - http://moodle.org/
//
// Moodle 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 3 of the License, or
// (at your option) any later version.
//
// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * This file is responsible for serving of yui images
 *
 * @package   moodlecore
 * @copyright 2009 Petr Skoda (skodak)  {@link http://skodak.org}
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */


// we need just the values from config.php and minlib.php
define('ABORT_AFTER_CONFIG', true);
require('../config.php'); // this stops immediately at the beginning of lib/setup.php

// get special url parameters
if (!$parts = combo_params()) {
    combo_not_found();
}

$parts = trim($parts, '&');

// find out what we are serving - only one type per request
$content = '';
if (substr($parts, -3) === '.js') {
    $mimetype = 'application/x-javascript';
} else if (substr($parts, -4) === '.css') {
    $mimetype = 'text/css';
} else {
    combo_not_found();
}

$parts = explode('&', $parts);

foreach ($parts as $part) {
    if (empty($part)) {
        continue;
    }
    $part = min_clean_param($part, 'SAFEPATH');
    $bits = explode('/', $part);
    if (count($bits) < 2) {
        $content .= "\n// Wrong combo resource $part!\n";
        continue;
    }
    $version = $bits[0];
    if ($version != $CFG->yui3version and $version != $CFG->yui2version) {
        $content .= "\n// Wrong yui version $part!\n";
        continue;
    }
    $contentfile = "$CFG->libdir/yui/$part";
    if (!file_exists($contentfile) or !is_file($contentfile)) {
        $content .= "\n// Combo resource $part not found!\n";
        continue;
    }
    $filecontent = file_get_contents($contentfile);

    if ($mimetype === 'text/css') {
        // search for all images in yui2 CSS and serve them through the yui_image.php script
        $filecontent = preg_replace('/([a-z_-]+)\.(png|gif)/', 'yui_image.php?file='.$version.'/$1.$2', $filecontent);
    }

    $content .= $filecontent;
}


combo_send_cached($content, $mimetype);


function combo_send_cached($content, $mimetype) {
    $lifetime = 60*60*24*300; // 300 days === forever

    header('Content-Disposition: inline; filename="combo"');
    header('Last-Modified: '. gmdate('D, d M Y H:i:s', time()) .' GMT');
    header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
    header('Pragma: ');
    header('Cache-Control: max-age=315360000');
    header('Accept-Ranges: none');
    header('Content-Type: '.$mimetype);
    if (!min_enable_zlib_compression()) {
        header('Content-Length: '.strlen($content));
    }

    echo $content;
    die;
}

function combo_not_found() {
    header('HTTP/1.0 404 not found');
    die('Combo resource not found, sorry.');
}

function combo_params() {
    if (!empty($_SERVER['REQUEST_URI'])) {
        $parts = explode('?', $_SERVER['REQUEST_URI']);
        if (count($parts) != 2) {
            return '';
        }
        return $parts[1];

    } else if (!empty($_SERVER['QUERY_STRING'])) {
        return $_SERVER['QUERY_STRING'];

    } else {
        return '';
    }
}