<?php
/* For licensing terms, see /license.txt */
/**
 * This file is responsible for  passing requested documents to the browser.
 * Html files are parsed to fix a few problems with URLs,
 * but this code will hopefully be replaced soon by an Apache URL
 * rewrite mechanism.
 *
 * @package chamilo.announcements
 */
session_cache_limiter('nocache');

require_once __DIR__.'/../inc/global.inc.php';

// IMPORTANT to avoid caching of documents
header('Expires: Wed, 01 Jan 1990 00:00:00 GMT');
header('Cache-Control: public');
header('Pragma: no-cache');

//protection
api_protect_course_script(true);

$doc_url = $_GET['file'];
//change the '&' that got rewritten to '///' by mod_rewrite back to '&'
$doc_url = str_replace('///', '&', $doc_url);
//still a space present? it must be a '+' (that got replaced by mod_rewrite)
$doc_url = str_replace(' ', '+', $doc_url);
$doc_url = str_replace('/..', '', $doc_url); //echo $doc_url;

if (strpos($doc_url, '../') || strpos($doc_url, '/..')) {
    $doc_url = '';
}

if (!isset($_course)) {
    api_not_allowed(true);
}

$full_file_name = api_get_path(SYS_COURSE_PATH).api_get_course_path().'/upload/announcements/'.$doc_url;

//if the rewrite rule asks for a directory, we redirect to the document explorer
if (is_dir($full_file_name)) {
    //remove last slash if present
    //$doc_url = ($doc_url{strlen($doc_url)-1}=='/')?substr($doc_url,0,strlen($doc_url)-1):$doc_url;
    //mod_rewrite can change /some/path/ to /some/path// in some cases, so clean them all off (René)
    while ($doc_url[$dul = strlen($doc_url) - 1] == '/') {
        $doc_url = substr($doc_url, 0, $dul);
    }
    //create the path
    $document_explorer = api_get_path(WEB_COURSE_PATH).api_get_course_path(); // home course path
    //redirect
    header('Location: '.$document_explorer);
    exit;
}

$table = Database::get_course_table(TABLE_ANNOUNCEMENT_ATTACHMENT);

// launch event
Event::event_download($doc_url);
$course_id = api_get_course_int_id();
$doc_url = Database::escape_string($doc_url);

$sql = "SELECT filename FROM $table
  	  	WHERE c_id = $course_id AND path LIKE BINARY '$doc_url'";

$result = Database::query($sql);
if (Database::num_rows($result) > 0) {
    $row = Database::fetch_array($result);
    $title = str_replace(' ', '_', $row['filename']);
    if (Security::check_abs_path(
        $full_file_name,
        api_get_path(SYS_COURSE_PATH).api_get_course_path().'/upload/announcements/'
    )
    ) {
        $result = DocumentManager::file_send_for_download($full_file_name, true, $title);
        if ($result === false) {
            api_not_allowed(true);
        }
    }
}
exit;