subscribe.php

<?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/>.

require_once(dirname(__FILE__, 3) .'/config.php');
require_once(__DIR__ . '/lib.php');
$id = required_param(NEWSLETTER_PARAM_ID, PARAM_INT);
$user = optional_param(NEWSLETTER_PARAM_USER, 0, PARAM_INT);
$confirm = optional_param(NEWSLETTER_PARAM_CONFIRM, NEWSLETTER_CONFIRM_UNKNOWN, PARAM_INT);
$secret = optional_param(NEWSLETTER_PARAM_HASH, false, PARAM_TEXT);

// Create a new user if the user has used the guest subscription form.
if ($user) {
    global $DB;
    $select = " userid = $user AND (health = " . NEWSLETTER_SUBSCRIBER_STATUS_OK . " OR health = " .
            NEWSLETTER_SUBSCRIBER_STATUS_PROBLEMATIC . ")";
    $sub = $DB->record_exists_select('newsletter_subscriptions', $select);
    $user = $DB->get_record('user', array('id' => $user), '*', MUST_EXIST);
    // If the passed secret matches the secret connected to the user it is a guest subscription.
    if ($sub && $secret && $secret === $user->secret) {
        if ($confirm == NEWSLETTER_CONFIRM_YES) {
            $DB->set_field('user', 'confirmed', 1, array('id' => $user));
            redirect(new moodle_url('/mod/newsletter/view.php', array('id' => $id)),
                    get_string('welcomeredirec', 'mod_newsletter'), 5);
        } else if ($confirm == NEWSLETTER_CONFIRM_NO) {
            $DB->delete_records('newsletter_subscriptions', array('userid' => $user));
            $user = $DB->get_record('user', array('id' => $user));
            user_delete_user($user);
            redirect(new moodle_url('/mod/newsletter/view.php', array('id' => $id)),
                    "The creation of your account was cancelled at your request!", 5);
        } else {
            throw new \moodle_exception('The link you followed is invalid.', 'mod_newsletter');
        }
    }
} else {
    $user = $USER;
}

$url = new moodle_url('/mod/newsletter/subscribe.php', array('id' => $id));
$PAGE->set_url($url);
$coursemodule = get_coursemodule_from_id('newsletter', $id, 0, false, MUST_EXIST);
$course = $DB->get_record('course', array('id' => $coursemodule->course), '*', MUST_EXIST);

$PAGE->set_context(context_system::instance()); // No login required.
$context = context_module::instance($coursemodule->id);

$newsletter = mod_newsletter\newsletter::get_newsletter_by_course_module($id);

if ($newsletter->is_subscribed($user->id)) {
    if ($confirm == NEWSLETTER_CONFIRM_UNKNOWN) {
        echo $OUTPUT->header();
        // Post the secret to the confirm step.
        if ($secret === md5($user->id . "+" . $user->firstaccess)) {
            echo $OUTPUT->confirm(
                    get_string('unsubscribe_question', 'newsletter',
                            array('name' => $newsletter->get_instance()->name,
                                'email' => $user->email)),
                    new moodle_url($url,
                            array(NEWSLETTER_PARAM_USER => $user->id,
                                NEWSLETTER_PARAM_HASH => $secret,
                                NEWSLETTER_PARAM_CONFIRM => NEWSLETTER_CONFIRM_YES)),
                    new moodle_url($url,
                            array(NEWSLETTER_PARAM_USER => $user->id,
                                NEWSLETTER_PARAM_CONFIRM => NEWSLETTER_CONFIRM_NO)));
        } else {
            echo \core\notification::error('You used an invalid unsubscription link');
        }
        echo $OUTPUT->footer();
    } else if ($confirm == NEWSLETTER_CONFIRM_YES) {
        // Check if secret value is correct.
        // NOTE: this makes all older unsub links invalid.
        if ($secret === md5($user->id . "+" . $user->firstaccess)) {
            $subscriptionid = $newsletter->get_subid($user->id);
            $newsletter->unsubscribe($subscriptionid);
            // Send mail to user just to be sure.
            $a = new stdClass();
            $a->firstname = $user->firstname;
            $a->lastname = $user->lastname;
            $a->newsletterurl = $newsletter->get_subsribe_url()->out();
            $a->newslettertitle = $newsletter->get_instance()->name;
            $unsubsubj = get_string('unsubscribe_mail_subj', 'newsletter');
            $unsubtext = get_string('unsubscribe_mail_text', 'newsletter', $a); // TODO: Make this
                                                                                // prettier.
            email_to_user($user, core_user::get_support_user(), $unsubsubj,
                    html_to_text($unsubtext), $unsubtext, '', '', false);
            echo $OUTPUT->header();
            $stringparams = array('name' => $newsletter->get_instance()->name,
                'email' => $user->email);
            echo $OUTPUT->box(get_string('unsubscription_succesful', 'newsletter', $stringparams),
                    'mdl-align');
            echo $OUTPUT->continue_button(
                    new moodle_url('/mod/newsletter/view.php', array('id' => $id)));
            echo $OUTPUT->footer();
        } else {
            redirect(new moodle_url('/mod/newsletter/view.php', array('id' => $id)));
        }
    } else if ($confirm == NEWSLETTER_CONFIRM_NO) {
        redirect(new moodle_url('/mod/newsletter/view.php', array('id' => $id)));
    } else {
        throw new \moodle_exception('Wrong ' . NEWSLETTER_PARAM_CONFIRM . ' code: ' . $confirm . '!');
    }
} else {
    require_capability('mod/newsletter:viewnewsletter', $context);
    if ($confirm == NEWSLETTER_CONFIRM_UNKNOWN) {
        echo $OUTPUT->header();
        $urlparams = array(NEWSLETTER_PARAM_USER => $user->id,
            NEWSLETTER_PARAM_CONFIRM => NEWSLETTER_CONFIRM_YES);
        $urlparams2 = array(NEWSLETTER_PARAM_USER => $user->id,
            NEWSLETTER_PARAM_CONFIRM => NEWSLETTER_CONFIRM_NO);
        echo $OUTPUT->confirm(
                get_string('subscribe_question', 'newsletter',
                        array('name' => $newsletter->get_instance()->name, 'email' => $user->email)),
                new moodle_url($url, $urlparams), new moodle_url($url, $urlparams2));
        echo $OUTPUT->footer();
    } else if ($confirm == NEWSLETTER_CONFIRM_YES) {
        $newsletter->subscribe($user->id);
        redirect(new moodle_url('/mod/newsletter/view.php', array('id' => $id)));
    } else if ($confirm == NEWSLETTER_CONFIRM_NO) {
        redirect(new moodle_url('/mod/newsletter/view.php', array('id' => $id)));
    } else {
        throw new \moodle_exception('Wrong ' . NEWSLETTER_PARAM_CONFIRM . ' code: ' . $confirm . '!',
                'mod_newsletter');
    }
}

die();