<?php
require_once("../../config.php");
require_once($CFG->dirroot . '/backup/util/includes/backup_includes.php');
require_once($CFG->dirroot . "/backup/util/includes/restore_includes.php");

$courseid = $_GET["courseid"];
$categoryid = $_GET["categoryid"];
$timestamp = $_GET["timestamp"];

try {
    $course = get_course($courseid);
} catch (Exception $ex) {
    $course = null;
}

if (!$course) {
    if (!get_course(((int) $courseid) - 1)) {
        die("Cannot recreate course with this ID!");
    }
}

if ($course && !$categoryid) {
    $categoryid = $course->category;
}

$category = $DB->get_record('course_categories', array('id' => $categoryid), '*', MUST_EXIST);

$replicationconfig = get_config('local_replication');
$directory = $replicationconfig->directory;

$infile = $directory . DIRECTORY_SEPARATOR . "course_" . $courseid . "_" . $categoryid . "_" . $timestamp . ".mbz";

if (empty($CFG->tempdir)) {
    $CFG->tempdir = $CFG->dataroot . DIRECTORY_SEPARATOR . 'temp';
}

if (!file_exists($infile)) {
    die("Backup file '" . $infile . "' does not exist.");
}

if (!is_readable($infile)) {
    die("Backup file '" . $infile . "' is not readable.");
}

$backupdir = "restore_" . uniqid();

if (isset($CFG->backuptempdir)){
    $path = $CFG->backuptempdir . DIRECTORY_SEPARATOR . $backupdir;
}
else{
    $path = $CFG->tempdir . DIRECTORY_SEPARATOR . "backup" . DIRECTORY_SEPARATOR . $backupdir;
}

$fp = get_file_packer('application/vnd.moodle.backup');
$fp->extract_to_pathname($infile, $path);

$xmlfile = $path . DIRECTORY_SEPARATOR . "course" . DIRECTORY_SEPARATOR . "course.xml";

$xml = simplexml_load_file($xmlfile);
$fullname = $xml->xpath('/course/fullname');
if (!$fullname) {
    $fullname = $xml->xpath('/MOODLE_BACKUP/COURSE/HEADER/FULLNAME');
}
$shortname = $xml->xpath('/course/shortname');
if (!$shortname) {
    $shortname = $xml->xpath('/MOODLE_BACKUP/COURSE/HEADER/SHORTNAME');
}

$fullname = (string)($fullname[0]);
$shortname = (string)($shortname[0]);

if (!$fullname) {
    $fullname = $shortname;
}

if (!$course && $DB->get_record('course', array('category' => $category->id, 'shortname' => $shortname))) {
    $matches = NULL;
    preg_match('/(.*)_(\d+)$/', $shortname, $matches);
    if ($matches) {
        $base = $matches[1];
        $number = $matches[2];
    } else {
        $base = $shortname;
        $number = 1;
    }
    $shortname = $base . '_' . $number;
    while ($DB->get_record('course', array('category' => $category->id, 'shortname' => $shortname))) {
        $number++;
        $shortname = $base . '_' . $number;
    }
}

if ($course) {
    echo "Overwriting current content of existing course -> Course ID: $courseid\n";
    $rc = new restore_controller($backupdir, $courseid, backup::INTERACTIVE_NO,
        backup::MODE_GENERAL, $USER->id, 0);
} else {
    echo "Creating new course to restore backup\n";
    $courseid = restore_dbops::create_new_course($fullname, $shortname, $category->id);
    $rc = new restore_controller($backupdir, $courseid, backup::INTERACTIVE_NO,
        backup::MODE_GENERAL, $USER->id, backup::TARGET_NEW_COURSE);
}

if ($rc->get_status() == backup::STATUS_REQUIRE_CONV) {
    $rc->convert();
}

$plan = $rc->get_plan();

if (!$rc->execute_precheck()){
    $check = $rc->get_precheck_results();
    echo("Restore pre-check failed!");
    var_dump($check);
    die();
}

$deletingoptions = array();
$deletingoptions['keep_roles_and_enrolments'] = 1;
$deletingoptions['keep_groups_and_groupings'] = 1;
restore_dbops::delete_course_content($courseid, $deletingoptions);

$rc->execute_plan();
$rc->destroy();

#unlink($infile);

$course = get_course($courseid);

$course->category = $categoryid;
$course->fullname = $fullname;
$course->shortname = $shortname;

$DB->update_record('course', $course);

echo "New course ID for '$shortname': $courseid in category {$category->id}\n";
echo "OK"