<?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 page handles deleting quiz overrides
 *
 * @package mod_quiz
 * @copyright 2010 Matt Petro
 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

require_once(dirname(__FILE__) . '/../../config.php');
require_once($CFG->dirroot.'/mod/quiz/lib.php');
require_once($CFG->dirroot.'/mod/quiz/locallib.php');
require_once($CFG->dirroot.'/mod/quiz/override_form.php');

$overrideid = required_param('id', PARAM_INT);  // override ID
$confirm = optional_param('confirm', false, PARAM_BOOL); // already confirmed?

if (! $override = $DB->get_record('quiz_overrides', array('id' => $overrideid))) {
    print_error('invalidoverrideid', 'quiz');
}
if (! $quiz = $DB->get_record('quiz', array('id' => $override->quiz))) {
    print_error('invalidcoursemodule');
}
if (! $cm = get_coursemodule_from_instance("quiz", $quiz->id, $quiz->course)) {
    print_error('invalidcoursemodule');
}

$context = get_context_instance(CONTEXT_MODULE, $cm->id);

require_login($cm->course, false, $cm);

// Check the user has the required capabilities to modify an override
require_capability('mod/quiz:manageoverrides', $context);

$url = new moodle_url('/mod/quiz/overridedelete.php', array('id'=>$override->id));
$confirmurl = new moodle_url($url, array('id'=>$override->id, 'confirm'=>1));
$cancelurl = new moodle_url('/mod/quiz/overrides.php', array('cmid'=>$cm->id));

if (!empty($override->userid)) {
    $cancelurl->param('mode', 'user');
}

// If confirm is set (PARAM_BOOL) then we have confirmation of intention to delete
if ($confirm) {
    // Confirm the session key to stop CSRF
    require_sesskey();

    // Remove the override
    quiz_delete_override($quiz, $override->id);

    add_to_log($cm->course, 'quiz', 'delete override',
        "overrides.php?cmid=$cm->id", $quiz->id, $cm->id);

    // And redirect
    redirect($cancelurl);
}

// Prepare the page to show the confirmation form
$stroverride = get_string('override', 'quiz');
$title = get_string('deletecheck', null, $stroverride);

$PAGE->set_url($url);
$PAGE->navbar->add($title);
$PAGE->set_title($title);
$PAGE->set_heading($stroverride);

echo $OUTPUT->header();

if ($override->groupid) {
    $group = $DB->get_record('groups', array('id' => $override->groupid), 'id,name');
    $confirmstr = get_string("overridedeletegroupsure", "quiz", $group->name);
}
else {
    $user = $DB->get_record('user', array('id' => $override->userid), 'id,firstname,lastname');
    $confirmstr = get_string("overridedeleteusersure", "quiz", fullname($user));
}

echo $OUTPUT->confirm($confirmstr, $confirmurl, $cancelurl);

echo $OUTPUT->footer();
