<?php

/**
 +-----------------------------------------------------------------------+
 | This file is part of the Roundcube Webmail client                     |
 |                                                                       |
 | Copyright (C) The Roundcube Dev Team                                  |
 |                                                                       |
 | Licensed under the GNU General Public License version 3 or            |
 | any later version with exceptions for skins & plugins.                |
 | See the README file for a full license statement.                     |
 |                                                                       |
 | PURPOSE:                                                              |
 |   Modify CSS source from a URL                                        |
 +-----------------------------------------------------------------------+
 | Author: Thomas Bruederli <roundcube@gmail.com>                        |
 | Author: Aleksander Machniak <alec@alec.pl>                            |
 +-----------------------------------------------------------------------+
*/

$url = preg_replace('![^a-z0-9.-]!i', '', $_GET['_u']);

if ($url === null || !($realurl = $_SESSION['modcssurls'][$url])) {
    header('HTTP/1.1 403 Forbidden');
    exit("Unauthorized request");
}

// don't allow any other connections than http(s)
if (!preg_match('~^(https?)://~i', $realurl, $matches)) {
    header('HTTP/1.1 403 Forbidden');
    exit("Invalid URL");
}

if (ini_get('allow_url_fopen')) {
    $scheme  = strtolower($matches[1]);
    $options = array(
        $scheme => array(
            'method' => 'GET',
            'timeout' => 15,
        )
    );

    $context = stream_context_create($options);
    $source  = @file_get_contents($realurl, false, $context);

    // php.net/manual/en/reserved.variables.httpresponseheader.php
    $headers = implode("\n", (array) $http_response_header);
}
else if (function_exists('curl_init')) {
    $curl = curl_init($realurl);
    curl_setopt($curl, CURLOPT_TIMEOUT, 15);
    curl_setopt($curl, CURLOPT_CONNECTTIMEOUT, 15);
    curl_setopt($curl, CURLOPT_PROTOCOLS, CURLPROTO_HTTP | CURLPROTO_HTTPS);
    curl_setopt($curl, CURLOPT_ENCODING, '');
    curl_setopt($curl, CURLOPT_HEADER, true);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
    $data = curl_exec($curl);

    if ($data !== false) {
        list($headers, $source) = explode("\r\n\r\n", $data, 2);
    }
    else {
        $headers = false;
        $source  = false;
    }
}
else {
    header('HTTP/1.1 403 Forbidden');
    exit("HTTP connections disabled");
}

$ctype_regexp = '~Content-Type:\s+text/(css|plain)~i';
$container_id = preg_replace('/[^a-z0-9]/i', '', $_GET['_c']);
$css_prefix   = preg_replace('/[^a-z0-9]/i', '', $_GET['_p']);

if ($source !== false && preg_match($ctype_regexp, $headers)) {
    header('Content-Type: text/css');
    echo rcube_utils::mod_css_styles($source, $container, false, $css_prefix);
    exit;
}

header('HTTP/1.0 404 Not Found');
exit("Invalid response returned by server");