<?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/>.

/**
 * Moves, adds, updates, duplicates or deletes modules in a course
 *
 * @copyright 1999 Martin Dougiamas  http://dougiamas.com
 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 * @package course
 */

require("../config.php");
require_once("lib.php");

require_login();

$sectionreturn = optional_param('sr', '', PARAM_INT);
$add           = optional_param('add', '', PARAM_ALPHA);
$type          = optional_param('type', '', PARAM_ALPHA);
$indent        = optional_param('indent', 0, PARAM_INT);
$update        = optional_param('update', 0, PARAM_INT);
$hide          = optional_param('hide', 0, PARAM_INT);
$show          = optional_param('show', 0, PARAM_INT);
$copy          = optional_param('copy', 0, PARAM_INT);
$moveto        = optional_param('moveto', 0, PARAM_INT);
$movetosection = optional_param('movetosection', 0, PARAM_INT);
$delete        = optional_param('delete', 0, PARAM_INT);
$course        = optional_param('course', 0, PARAM_INT);
$groupmode     = optional_param('groupmode', -1, PARAM_INT);
$cancelcopy    = optional_param('cancelcopy', 0, PARAM_BOOL);
$confirm       = optional_param('confirm', 0, PARAM_BOOL);

// This page should always redirect
$url = new moodle_url('/course/mod.php');
foreach (compact('indent','update','hide','show','copy','moveto','movetosection','delete','course','cancelcopy','confirm') as $key=>$value) {
    if ($value !== 0) {
        $url->param($key, $value);
    }
}
if ($sectionreturn !== '') {
    $url->param('sr', $sectionreturn);
}
if ($add !== '') {
    $url->param('add', $add);
}
if ($type !== '') {
    $url->param('type', $type);
}
if ($groupmode !== '') {
    $url->param('groupmode', $groupmode);
}
$PAGE->set_url($url);

//check if we are adding / editing a module that has new forms using formslib
if (!empty($add)) {
    $id          = required_param('id', PARAM_INT);
    $section     = required_param('section', PARAM_INT);
    $type        = optional_param('type', '', PARAM_ALPHA);
    $returntomod = optional_param('return', 0, PARAM_BOOL);

    redirect("$CFG->wwwroot/course/modedit.php?add=$add&type=$type&course=$id&section=$section&return=$returntomod");

} else if (!empty($update)) {
    if (!$cm = get_coursemodule_from_id('', $update, 0, true)) {
        print_error('invalidcoursemodule');
    }
    $returntomod = optional_param('return', 0, PARAM_BOOL);
    redirect("$CFG->wwwroot/course/modedit.php?update=$update&return=$returntomod");

} else if (!empty($delete)) {
    if (!$cm = get_coursemodule_from_id('', $delete, 0, true)) {
        print_error('invalidcoursemodule');
    }

    if (!$course = $DB->get_record('course', array('id'=>$cm->course))) {
        print_error('invalidcourseid');
    }
    require_login($course->id); // needed to setup proper $COURSE
    $context = get_context_instance(CONTEXT_COURSE, $course->id);
    $modcontext = get_context_instance(CONTEXT_MODULE, $cm->id);
    require_capability('moodle/course:manageactivities', $context);

    $return = "$CFG->wwwroot/course/view.php?id=$cm->course#section-$cm->sectionnum";

    if (!$confirm or !confirm_sesskey()) {
        $fullmodulename = get_string('modulename', $cm->modname);

        $optionsyes = array('confirm'=>1, 'delete'=>$cm->id, 'sesskey'=>sesskey());
        $optionsno  = array('id'=>$cm->course);

        $strdeletecheck = get_string('deletecheck', '', $fullmodulename);
        $strdeletecheckfull = get_string('deletecheckfull', '', "$fullmodulename '$cm->name'");

        $PAGE->set_pagetype('mod-' . $cm->modname . '-delete');
        $PAGE->set_title($strdeletecheck);
        $PAGE->set_heading($course->fullname);
        $PAGE->navbar->add($strdeletecheck);
        echo $OUTPUT->header();

        // print_simple_box_start('center', '60%', '#FFAAAA', 20, 'noticebox');
        echo $OUTPUT->box_start('noticebox');
        $formcontinue = new single_button(new moodle_url("$CFG->wwwroot/course/mod.php", $optionsyes), get_string('yes'));
        $formcancel = new single_button(new moodle_url($return, $optionsno), get_string('no'), 'get');
        echo $OUTPUT->confirm($strdeletecheckfull, $formcontinue, $formcancel);
        echo $OUTPUT->box_end();
        echo $OUTPUT->footer();

        exit;
    }

    $modlib = "$CFG->dirroot/mod/$cm->modname/lib.php";

    if (file_exists($modlib)) {
        require_once($modlib);
    } else {
        print_error('modulemissingcode', '', '', $modlib);
    }

    $deleteinstancefunction = $cm->modname."_delete_instance";

    if (!$deleteinstancefunction($cm->instance)) {
        echo $OUTPUT->notification("Could not delete the $cm->modname (instance)");
    }

    // remove all module files in case modules forget to do that
    $fs = get_file_storage();
    $fs->delete_area_files($modcontext->id);

    if (!delete_course_module($cm->id)) {
        echo $OUTPUT->notification("Could not delete the $cm->modname (coursemodule)");
    }
    if (!delete_mod_from_section($cm->id, $cm->section)) {
        echo $OUTPUT->notification("Could not delete the $cm->modname from that section");
    }

    // Trigger a mod_deleted event with information about this module.
    $eventdata = new stdClass();
    $eventdata->modulename = $cm->modname;
    $eventdata->cmid       = $cm->id;
    $eventdata->courseid   = $course->id;
    $eventdata->userid     = $USER->id;
    events_trigger('mod_deleted', $eventdata);

    add_to_log($course->id, 'course', "delete mod",
               "view.php?id=$cm->course",
               "$cm->modname $cm->instance", $cm->id);

    rebuild_course_cache($course->id);

    redirect($return);
}


if ((!empty($movetosection) or !empty($moveto)) and confirm_sesskey()) {
    if (!$cm = get_coursemodule_from_id('', $USER->activitycopy, 0, true)) {
        print_error('invalidcoursemodule');
    }

    if (!empty($movetosection)) {
        if (!$section = $DB->get_record('course_sections', array('id'=>$movetosection, 'course'=>$cm->course))) {
            print_error('sectionnotexist');
        }
        $beforecm = NULL;

    } else {                      // normal moveto
        if (!$beforecm = get_coursemodule_from_id('', $moveto, $cm->course, true)) {
            print_error('invalidcoursemodule');
        }
        if (!$section = $DB->get_record('course_sections', array('id'=>$beforecm->section, 'course'=>$cm->course))) {
            print_error('sectionnotexist');
        }
    }

    require_login($section->course); // needed to setup proper $COURSE
    $context = get_context_instance(CONTEXT_COURSE, $section->course);
    require_capability('moodle/course:manageactivities', $context);

    if (!ismoving($section->course)) {
        print_error('needcopy', '', "view.php?id=$section->course");
    }

    moveto_module($cm, $section, $beforecm);

    unset($USER->activitycopy);
    unset($USER->activitycopycourse);
    unset($USER->activitycopyname);

    rebuild_course_cache($section->course);

    if (SITEID == $section->course) {
        redirect($CFG->wwwroot);
    } else {
        redirect("view.php?id=$section->course#section-$sectionreturn");
    }

} else if (!empty($indent) and confirm_sesskey()) {
    $id = required_param('id', PARAM_INT);
    if (!$cm = get_coursemodule_from_id('', $id, 0, true)) {
        print_error('invalidcoursemodule');
    }

    require_login($cm->course); // needed to setup proper $COURSE
    $context = get_context_instance(CONTEXT_COURSE, $cm->course);
    require_capability('moodle/course:manageactivities', $context);

    $cm->indent += $indent;

    if ($cm->indent < 0) {
        $cm->indent = 0;
    }

    $DB->set_field('course_modules', 'indent', $cm->indent, array('id'=>$cm->id));

    rebuild_course_cache($cm->course);

    if (SITEID == $cm->course) {
        redirect($CFG->wwwroot);
    } else {
        redirect("view.php?id=$cm->course#section-$cm->sectionnum");
    }

} else if (!empty($hide) and confirm_sesskey()) {
    if (!$cm = get_coursemodule_from_id('', $hide, 0, true)) {
        print_error('invalidcoursemodule');
    }

    require_login($cm->course); // needed to setup proper $COURSE
    $context = get_context_instance(CONTEXT_MODULE, $cm->id);
    require_capability('moodle/course:activityvisibility', $context);

    set_coursemodule_visible($cm->id, 0);

    rebuild_course_cache($cm->course);

    if (SITEID == $cm->course) {
        redirect($CFG->wwwroot);
    } else {
        redirect("view.php?id=$cm->course#section-$cm->sectionnum");
    }

} else if (!empty($show) and confirm_sesskey()) {
    if (!$cm = get_coursemodule_from_id('', $show, 0, true)) {
        print_error('invalidcoursemodule');
    }

    require_login($cm->course); // needed to setup proper $COURSE
    $context = get_context_instance(CONTEXT_COURSE, $cm->course);
    require_capability('moodle/course:activityvisibility', $context);

    if (!$section = $DB->get_record('course_sections', array('id'=>$cm->section))) {
        print_error('sectionnotexist');
    }

    if (!$module = $DB->get_record('modules', array('id'=>$cm->module))) {
        print_error('moduledoesnotexist');
    }

    if ($module->visible and ($section->visible or (SITEID == $cm->course))) {
        set_coursemodule_visible($cm->id, 1);
        rebuild_course_cache($cm->course);
    }

    if (SITEID == $cm->course) {
        redirect($CFG->wwwroot);
    } else {
        redirect("view.php?id=$cm->course#section-$cm->sectionnum");
    }

} else if ($groupmode > -1 and confirm_sesskey()) {
    $id = required_param('id', PARAM_INT);
    if (!$cm = get_coursemodule_from_id('', $id, 0, true)) {
        print_error('invalidcoursemodule');
    }

    require_login($cm->course); // needed to setup proper $COURSE
    $context = get_context_instance(CONTEXT_MODULE, $cm->id);
    require_capability('moodle/course:manageactivities', $context);

    set_coursemodule_groupmode($cm->id, $groupmode);

    rebuild_course_cache($cm->course);

    if (SITEID == $cm->course) {
        redirect($CFG->wwwroot);
    } else {
        redirect("view.php?id=$cm->course#section-$cm->sectionnum");
    }

} else if (!empty($copy) and confirm_sesskey()) { // value = course module
    if (!$cm = get_coursemodule_from_id('', $copy, 0, true)) {
        print_error('invalidcoursemodule');
    }

    require_login($cm->course); // needed to setup proper $COURSE
    $context = get_context_instance(CONTEXT_COURSE, $cm->course);
    require_capability('moodle/course:manageactivities', $context);

    if (!$section = $DB->get_record('course_sections', array('id'=>$cm->section))) {
        print_error('sectionnotexist');
    }

    $USER->activitycopy       = $copy;
    $USER->activitycopycourse = $cm->course;
    $USER->activitycopyname   = $cm->name;

    redirect("view.php?id=$cm->course#section-$sectionreturn");

} else if (!empty($cancelcopy) and confirm_sesskey()) { // value = course module

    $courseid = $USER->activitycopycourse;

    unset($USER->activitycopy);
    unset($USER->activitycopycourse);
    unset($USER->activitycopyname);

    redirect("view.php?id=$courseid");

} else {
    print_error('unknowaction');
}