<?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/>.

/**
 * External message functions unit tests
 *
 * @package    core_message
 * @category   external
 * @copyright  2012 Jerome Mouneyrac
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

defined('MOODLE_INTERNAL') || die();

global $CFG;

require_once($CFG->dirroot . '/webservice/tests/helpers.php');
require_once($CFG->dirroot . '/message/externallib.php');

class core_message_externallib_testcase extends externallib_advanced_testcase {

    /**
     * Tests set up
     */
    protected function setUp() {
        global $CFG;

        require_once($CFG->dirroot . '/message/lib.php');
    }

    /**
     * Send a fake message.
     *
     * {@link message_send()} does not support transaction, this function will simulate a message
     * sent from a user to another. We should stop using it once {@link message_send()} will support
     * transactions. This is not clean at all, this is just used to add rows to the table.
     *
     * @param stdClass $userfrom user object of the one sending the message.
     * @param stdClass $userto user object of the one receiving the message.
     * @param string $message message to send.
     * @param int $notification is the message a notification.
     * @param int $time the time the message was sent
     */
    protected function send_message($userfrom, $userto, $message = 'Hello world!', $notification = 0, $time = 0) {
        global $DB;

        if (empty($time)) {
            $time = time();
        }

        $record = new stdClass();
        $record->useridfrom = $userfrom->id;
        $record->useridto = $userto->id;
        $record->subject = 'No subject';
        $record->smallmessage = $message;
        $record->fullmessage = $message;
        $record->timecreated = $time;
        $record->notification = $notification;
        $DB->insert_record('message', $record);
    }

    /**
     * Test send_instant_messages
     */
    public function test_send_instant_messages() {

        global $DB, $USER, $CFG;

        $this->resetAfterTest(true);
        // Transactions used in tests, tell phpunit use alternative reset method.
        $this->preventResetByRollback();

        // Turn off all message processors (so nothing is really sent)
        require_once($CFG->dirroot . '/message/lib.php');
        $messageprocessors = get_message_processors();
        foreach($messageprocessors as $messageprocessor) {
            $messageprocessor->enabled = 0;
            $DB->update_record('message_processors', $messageprocessor);
        }

        // Set the required capabilities by the external function
        $contextid = context_system::instance()->id;
        $roleid = $this->assignUserCapability('moodle/site:sendmessage', $contextid);

        $user1 = self::getDataGenerator()->create_user();

        // Create test message data.
        $message1 = array();
        $message1['touserid'] = $user1->id;
        $message1['text'] = 'the message.';
        $message1['clientmsgid'] = 4;
        $messages = array($message1);

        $sentmessages = core_message_external::send_instant_messages($messages);

        // We need to execute the return values cleaning process to simulate the web service server.
        $sentmessages = external_api::clean_returnvalue(core_message_external::send_instant_messages_returns(), $sentmessages);

        $themessage = $DB->get_record('message', array('id' => $sentmessages[0]['msgid']));

        // Confirm that the message was inserted correctly.
        $this->assertEquals($themessage->useridfrom, $USER->id);
        $this->assertEquals($themessage->useridto, $message1['touserid']);
        $this->assertEquals($themessage->smallmessage, $message1['text']);
        $this->assertEquals($sentmessages[0]['clientmsgid'], $message1['clientmsgid']);
    }

    /**
     * Test create_contacts.
     */
    public function test_create_contacts() {
        $this->resetAfterTest(true);

        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();
        $user4 = self::getDataGenerator()->create_user();
        $user5 = self::getDataGenerator()->create_user();
        $this->setUser($user1);

        // Adding a contact.
        $return = core_message_external::create_contacts(array($user2->id));
        $return = external_api::clean_returnvalue(core_message_external::create_contacts_returns(), $return);
        $this->assertEquals(array(), $return);

        // Adding a contact who is already a contact.
        $return = core_message_external::create_contacts(array($user2->id));
        $return = external_api::clean_returnvalue(core_message_external::create_contacts_returns(), $return);
        $this->assertEquals(array(), $return);

        // Adding multiple contacts.
        $return = core_message_external::create_contacts(array($user3->id, $user4->id));
        $return = external_api::clean_returnvalue(core_message_external::create_contacts_returns(), $return);
        $this->assertEquals(array(), $return);

        // Adding a non-existing user.
        $return = core_message_external::create_contacts(array(99999));
        $return = external_api::clean_returnvalue(core_message_external::create_contacts_returns(), $return);
        $this->assertCount(1, $return);
        $return = array_pop($return);
        $this->assertEquals($return['warningcode'], 'contactnotcreated');
        $this->assertEquals($return['itemid'], 99999);

        // Adding contacts with valid and invalid parameters.
        $return = core_message_external::create_contacts(array($user5->id, 99999));
        $return = external_api::clean_returnvalue(core_message_external::create_contacts_returns(), $return);
        $this->assertCount(1, $return);
        $return = array_pop($return);
        $this->assertEquals($return['warningcode'], 'contactnotcreated');
        $this->assertEquals($return['itemid'], 99999);

        // Try to add a contact to another user, should throw an exception.
        // All assertions must be added before this point.
        $this->expectException('required_capability_exception');
        core_message_external::create_contacts(array($user2->id), $user3->id);
    }

    /**
     * Test delete_contacts.
     */
    public function test_delete_contacts() {
        $this->resetAfterTest(true);

        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();
        $user4 = self::getDataGenerator()->create_user();
        $user5 = self::getDataGenerator()->create_user();
        $user6 = self::getDataGenerator()->create_user();
        $this->setUser($user1);
        $this->assertEquals(array(), core_message_external::create_contacts(
            array($user3->id, $user4->id, $user5->id, $user6->id)));

        // Removing a non-contact.
        $return = core_message_external::delete_contacts(array($user2->id));
        $this->assertNull($return);

        // Removing one contact.
        $return = core_message_external::delete_contacts(array($user3->id));
        $this->assertNull($return);

        // Removing multiple contacts.
        $return = core_message_external::delete_contacts(array($user4->id, $user5->id));
        $this->assertNull($return);

        // Removing contact from unexisting user.
        $return = core_message_external::delete_contacts(array(99999));
        $this->assertNull($return);

        // Removing mixed valid and invalid data.
        $return = core_message_external::delete_contacts(array($user6->id, 99999));
        $this->assertNull($return);

        // Try to delete a contact of another user contact list, should throw an exception.
        // All assertions must be added before this point.
        $this->expectException('required_capability_exception');
        core_message_external::delete_contacts(array($user2->id), $user3->id);
    }

    /**
     * Test block_contacts.
     */
    public function test_block_contacts() {
        $this->resetAfterTest(true);

        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();
        $user4 = self::getDataGenerator()->create_user();
        $user5 = self::getDataGenerator()->create_user();
        $this->setUser($user1);
        $this->assertEquals(array(), core_message_external::create_contacts(array($user3->id, $user4->id, $user5->id)));

        // Blocking a contact.
        $return = core_message_external::block_contacts(array($user2->id));
        $return = external_api::clean_returnvalue(core_message_external::block_contacts_returns(), $return);
        $this->assertEquals(array(), $return);

        // Blocking a contact who is already a contact.
        $return = core_message_external::block_contacts(array($user2->id));
        $return = external_api::clean_returnvalue(core_message_external::block_contacts_returns(), $return);
        $this->assertEquals(array(), $return);

        // Blocking multiple contacts.
        $return = core_message_external::block_contacts(array($user3->id, $user4->id));
        $return = external_api::clean_returnvalue(core_message_external::block_contacts_returns(), $return);
        $this->assertEquals(array(), $return);

        // Blocking a non-existing user.
        $return = core_message_external::block_contacts(array(99999));
        $return = external_api::clean_returnvalue(core_message_external::block_contacts_returns(), $return);
        $this->assertCount(1, $return);
        $return = array_pop($return);
        $this->assertEquals($return['warningcode'], 'contactnotblocked');
        $this->assertEquals($return['itemid'], 99999);

        // Blocking contacts with valid and invalid parameters.
        $return = core_message_external::block_contacts(array($user5->id, 99999));
        $return = external_api::clean_returnvalue(core_message_external::block_contacts_returns(), $return);
        $this->assertCount(1, $return);
        $return = array_pop($return);
        $this->assertEquals($return['warningcode'], 'contactnotblocked');
        $this->assertEquals($return['itemid'], 99999);

        // Try to block a contact of another user contact list, should throw an exception.
        // All assertions must be added before this point.
        $this->expectException('required_capability_exception');
        core_message_external::block_contacts(array($user2->id), $user3->id);
    }

    /**
     * Test unblock_contacts.
     */
    public function test_unblock_contacts() {
        $this->resetAfterTest(true);

        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();
        $user4 = self::getDataGenerator()->create_user();
        $user5 = self::getDataGenerator()->create_user();
        $user6 = self::getDataGenerator()->create_user();
        $this->setUser($user1);
        $this->assertEquals(array(), core_message_external::create_contacts(
            array($user3->id, $user4->id, $user5->id, $user6->id)));

        // Removing a non-contact.
        $return = core_message_external::unblock_contacts(array($user2->id));
        $this->assertNull($return);

        // Removing one contact.
        $return = core_message_external::unblock_contacts(array($user3->id));
        $this->assertNull($return);

        // Removing multiple contacts.
        $return = core_message_external::unblock_contacts(array($user4->id, $user5->id));
        $this->assertNull($return);

        // Removing contact from unexisting user.
        $return = core_message_external::unblock_contacts(array(99999));
        $this->assertNull($return);

        // Removing mixed valid and invalid data.
        $return = core_message_external::unblock_contacts(array($user6->id, 99999));
        $this->assertNull($return);

        // Try to unblock a contact of another user contact list, should throw an exception.
        // All assertions must be added before this point.
        $this->expectException('required_capability_exception');
        core_message_external::unblock_contacts(array($user2->id), $user3->id);
    }

    /**
     * Test get_contacts.
     */
    public function test_get_contacts() {
        $this->resetAfterTest(true);

        $user1 = self::getDataGenerator()->create_user();
        $user_stranger = self::getDataGenerator()->create_user();
        $user_offline1 = self::getDataGenerator()->create_user();
        $user_offline2 = self::getDataGenerator()->create_user();
        $user_offline3 = self::getDataGenerator()->create_user();
        $user_online = new stdClass();
        $user_online->lastaccess = time();
        $user_online = self::getDataGenerator()->create_user($user_online);
        $user_blocked = self::getDataGenerator()->create_user();
        $noreplyuser = core_user::get_user(core_user::NOREPLY_USER);

        // Login as user1.
        $this->setUser($user1);
        $this->assertEquals(array(), core_message_external::create_contacts(
            array($user_offline1->id, $user_offline2->id, $user_offline3->id, $user_online->id)));

        // User_stranger sends a couple of messages to user1.
        $this->send_message($user_stranger, $user1, 'Hello there!');
        $this->send_message($user_stranger, $user1, 'How you goin?');
        $this->send_message($user_stranger, $user1, 'Cya!');
        $this->send_message($noreplyuser, $user1, 'I am not a real user');

        // User_blocked sends a message to user1.
        $this->send_message($user_blocked, $user1, 'Here, have some spam.');

        // Retrieve the contacts of the user.
        $this->setUser($user1);
        $contacts = core_message_external::get_contacts();
        $contacts = external_api::clean_returnvalue(core_message_external::get_contacts_returns(), $contacts);
        $this->assertCount(3, $contacts['offline']);
        $this->assertCount(1, $contacts['online']);
        $this->assertCount(3, $contacts['strangers']);
        core_message_external::block_contacts(array($user_blocked->id));
        $contacts = core_message_external::get_contacts();
        $contacts = external_api::clean_returnvalue(core_message_external::get_contacts_returns(), $contacts);
        $this->assertCount(3, $contacts['offline']);
        $this->assertCount(1, $contacts['online']);
        $this->assertCount(2, $contacts['strangers']);

        // Checking some of the fields returned.
        $stranger = array_pop($contacts['strangers']);

        $this->assertEquals(core_user::NOREPLY_USER, $stranger['id']);
        $this->assertEquals(1, $stranger['unread']);

        // Check that deleted users are not returned.
        delete_user($user_offline1);
        delete_user($user_stranger);
        delete_user($user_online);
        $contacts = core_message_external::get_contacts();
        $contacts = external_api::clean_returnvalue(core_message_external::get_contacts_returns(), $contacts);
        $this->assertCount(2, $contacts['offline']);
        $this->assertCount(0, $contacts['online']);
        $this->assertCount(1, $contacts['strangers']);
    }

    /**
     * Test search_contacts.
     * @expectedException moodle_exception
     */
    public function test_search_contacts() {
        global $DB;
        $this->resetAfterTest(true);

        $course1 = $this->getDataGenerator()->create_course();
        $course2 = $this->getDataGenerator()->create_course();

        $user1 = new stdClass();
        $user1->firstname = 'X';
        $user1->lastname = 'X';
        $user1 = $this->getDataGenerator()->create_user($user1);
        $this->getDataGenerator()->enrol_user($user1->id, $course1->id);
        $this->getDataGenerator()->enrol_user($user1->id, $course2->id);

        $user2 = new stdClass();
        $user2->firstname = 'Eric';
        $user2->lastname = 'Cartman';
        $user2 = self::getDataGenerator()->create_user($user2);
        $user3 = new stdClass();
        $user3->firstname = 'Stan';
        $user3->lastname = 'Marsh';
        $user3 = self::getDataGenerator()->create_user($user3);
        self::getDataGenerator()->enrol_user($user3->id, $course1->id);
        $user4 = new stdClass();
        $user4->firstname = 'Kyle';
        $user4->lastname = 'Broflovski';
        $user4 = self::getDataGenerator()->create_user($user4);
        $user5 = new stdClass();
        $user5->firstname = 'Kenny';
        $user5->lastname = 'McCormick';
        $user5 = self::getDataGenerator()->create_user($user5);
        self::getDataGenerator()->enrol_user($user5->id, $course2->id);

        $this->setUser($user1);

        $results = core_message_external::search_contacts('r');
        $results = external_api::clean_returnvalue(core_message_external::search_contacts_returns(), $results);
        $this->assertCount(5, $results); // Users 2 through 5 + admin

        $results = core_message_external::search_contacts('r', true);
        $results = external_api::clean_returnvalue(core_message_external::search_contacts_returns(), $results);
        $this->assertCount(2, $results);

        $results = core_message_external::search_contacts('Kyle', false);
        $results = external_api::clean_returnvalue(core_message_external::search_contacts_returns(), $results);
        $this->assertCount(1, $results);
        $result = reset($results);
        $this->assertEquals($user4->id, $result['id']);

        $results = core_message_external::search_contacts('y', false);
        $results = external_api::clean_returnvalue(core_message_external::search_contacts_returns(), $results);
        $this->assertCount(2, $results);

        $results = core_message_external::search_contacts('y', true);
        $results = external_api::clean_returnvalue(core_message_external::search_contacts_returns(), $results);
        $this->assertCount(1, $results);
        $result = reset($results);
        $this->assertEquals($user5->id, $result['id']);

        // Empty query, will throw an exception.
        $results = core_message_external::search_contacts('');
    }

    /**
     * Test get_messages.
     */
    public function test_get_messages() {
        global $CFG, $DB;
        $this->resetAfterTest(true);

        $this->preventResetByRollback();
        // This mark the messages as read!.
        $sink = $this->redirectMessages();

        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();

        $course = self::getDataGenerator()->create_course();

        // Send a message from one user to another.
        message_post_message($user1, $user2, 'some random text 1', FORMAT_MOODLE);
        message_post_message($user1, $user3, 'some random text 2', FORMAT_MOODLE);
        message_post_message($user2, $user3, 'some random text 3', FORMAT_MOODLE);
        message_post_message($user3, $user2, 'some random text 4', FORMAT_MOODLE);
        message_post_message($user3, $user1, 'some random text 5', FORMAT_MOODLE);

        $this->setUser($user1);
        // Get read conversations from user1 to user2.
        $messages = core_message_external::get_messages($user2->id, $user1->id, 'conversations', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(1, $messages['messages']);

        // Delete the message.
        $message = array_shift($messages['messages']);
        $messagetobedeleted = $DB->get_record('message_read', array('id' => $message['id']));
        message_delete_message($messagetobedeleted, $user1->id);

        $messages = core_message_external::get_messages($user2->id, $user1->id, 'conversations', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(0, $messages['messages']);

        // Get unread conversations from user1 to user2.
        $messages = core_message_external::get_messages($user2->id, $user1->id, 'conversations', false, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(0, $messages['messages']);

        // Get read messages send from user1.
        $messages = core_message_external::get_messages(0, $user1->id, 'conversations', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(1, $messages['messages']);

        $this->setUser($user2);
        // Get read conversations from any user to user2.
        $messages = core_message_external::get_messages($user2->id, 0, 'conversations', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(2, $messages['messages']);

        // Conversations from user3 to user2.
        $messages = core_message_external::get_messages($user2->id, $user3->id, 'conversations', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(1, $messages['messages']);

        // Delete the message.
        $message = array_shift($messages['messages']);
        $messagetobedeleted = $DB->get_record('message_read', array('id' => $message['id']));
        message_delete_message($messagetobedeleted, $user2->id);

        $messages = core_message_external::get_messages($user2->id, $user3->id, 'conversations', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(0, $messages['messages']);

        $this->setUser($user3);
        // Get read notifications received by user3.
        $messages = core_message_external::get_messages($user3->id, 0, 'notifications', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(0, $messages['messages']);

        // Now, create some notifications...
        // We are creating fake notifications but based on real ones.

        // This one omits notification = 1.
        $eventdata = new \core\message\message();
        $eventdata->courseid          = $course->id;
        $eventdata->modulename        = 'moodle';
        $eventdata->component         = 'enrol_paypal';
        $eventdata->name              = 'paypal_enrolment';
        $eventdata->userfrom          = get_admin();
        $eventdata->userto            = $user1;
        $eventdata->subject           = "Moodle: PayPal payment";
        $eventdata->fullmessage       = "Your PayPal payment is pending.";
        $eventdata->fullmessageformat = FORMAT_PLAIN;
        $eventdata->fullmessagehtml   = '';
        $eventdata->smallmessage      = '';
        message_send($eventdata);

        $message = new \core\message\message();
        $message->courseid          = $course->id;
        $message->notification      = 1;
        $message->component         = 'enrol_manual';
        $message->name              = 'expiry_notification';
        $message->userfrom          = $user2;
        $message->userto            = $user1;
        $message->subject           = 'Enrolment expired';
        $message->fullmessage       = 'Enrolment expired blah blah blah';
        $message->fullmessageformat = FORMAT_MARKDOWN;
        $message->fullmessagehtml   = markdown_to_html($message->fullmessage);
        $message->smallmessage      = $message->subject;
        $message->contexturlname    = $course->fullname;
        $message->contexturl        = (string)new moodle_url('/course/view.php', array('id' => $course->id));
        message_send($message);

        $userfrom = core_user::get_noreply_user();
        $userfrom->maildisplay = true;
        $eventdata = new \core\message\message();
        $eventdata->courseid          = $course->id;
        $eventdata->component         = 'moodle';
        $eventdata->name              = 'badgecreatornotice';
        $eventdata->userfrom          = $userfrom;
        $eventdata->userto            = $user1;
        $eventdata->notification      = 1;
        $eventdata->subject           = 'New badge';
        $eventdata->fullmessage       = format_text_email($eventdata->subject, FORMAT_HTML);
        $eventdata->fullmessageformat = FORMAT_PLAIN;
        $eventdata->fullmessagehtml   = $eventdata->subject;
        $eventdata->smallmessage      = $eventdata->subject;
        message_send($eventdata);

        $eventdata = new \core\message\message();
        $eventdata->courseid         = $course->id;
        $eventdata->name             = 'submission';
        $eventdata->component        = 'mod_feedback';
        $eventdata->userfrom         = $user1;
        $eventdata->userto           = $user2;
        $eventdata->subject          = 'Feedback submitted';
        $eventdata->fullmessage      = 'Feedback submitted from an user';
        $eventdata->fullmessageformat = FORMAT_PLAIN;
        $eventdata->fullmessagehtml  = '<strong>Feedback submitted</strong>';
        $eventdata->smallmessage     = '';
        message_send($eventdata);

        $this->setUser($user1);
        // Get read notifications from any user to user1.
        $messages = core_message_external::get_messages($user1->id, 0, 'notifications', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(3, $messages['messages']);

        // Get one read notifications from any user to user1.
        $messages = core_message_external::get_messages($user1->id, 0, 'notifications', true, true, 0, 1);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(1, $messages['messages']);

        // Get unread notifications from any user to user1.
        $messages = core_message_external::get_messages($user1->id, 0, 'notifications', false, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(0, $messages['messages']);

        // Get read both type of messages from any user to user1.
        $messages = core_message_external::get_messages($user1->id, 0, 'both', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(4, $messages['messages']);

        // Get read notifications from no-reply-user to user1.
        $messages = core_message_external::get_messages($user1->id, $userfrom->id, 'notifications', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(1, $messages['messages']);

        // Get notifications send by user1 to any user.
        $messages = core_message_external::get_messages(0, $user1->id, 'notifications', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(1, $messages['messages']);

        // Test warnings.
        $CFG->messaging = 0;

        $messages = core_message_external::get_messages(0, $user1->id, 'both', true, true, 0, 0);
        $messages = external_api::clean_returnvalue(core_message_external::get_messages_returns(), $messages);
        $this->assertCount(1, $messages['warnings']);

        // Test exceptions.

        // Messaging disabled.
        try {
            $messages = core_message_external::get_messages(0, $user1->id, 'conversations', true, true, 0, 0);
            $this->fail('Exception expected due messaging disabled.');
        } catch (moodle_exception $e) {
            $this->assertEquals('disabled', $e->errorcode);
        }

        $CFG->messaging = 1;

        // Invalid users.
        try {
            $messages = core_message_external::get_messages(0, 0, 'conversations', true, true, 0, 0);
            $this->fail('Exception expected due invalid users.');
        } catch (moodle_exception $e) {
            $this->assertEquals('accessdenied', $e->errorcode);
        }

        // Invalid user ids.
        try {
            $messages = core_message_external::get_messages(2500, 0, 'conversations', true, true, 0, 0);
            $this->fail('Exception expected due invalid users.');
        } catch (moodle_exception $e) {
            $this->assertEquals('invaliduser', $e->errorcode);
        }

        // Invalid users (permissions).
        $this->setUser($user2);
        try {
            $messages = core_message_external::get_messages(0, $user1->id, 'conversations', true, true, 0, 0);
            $this->fail('Exception expected due invalid user.');
        } catch (moodle_exception $e) {
            $this->assertEquals('accessdenied', $e->errorcode);
        }

    }

    /**
     * Test get_blocked_users.
     */
    public function test_get_blocked_users() {
        $this->resetAfterTest(true);

        $user1 = self::getDataGenerator()->create_user();
        $userstranger = self::getDataGenerator()->create_user();
        $useroffline1 = self::getDataGenerator()->create_user();
        $useroffline2 = self::getDataGenerator()->create_user();
        $userblocked = self::getDataGenerator()->create_user();

        // Login as user1.
        $this->setUser($user1);
        $this->assertEquals(array(), core_message_external::create_contacts(
            array($useroffline1->id, $useroffline2->id)));

        // The userstranger sends a couple of messages to user1.
        $this->send_message($userstranger, $user1, 'Hello there!');
        $this->send_message($userstranger, $user1, 'How you goin?');

        // The userblocked sends a message to user1.
        // Note that this user is not blocked at this point.
        $this->send_message($userblocked, $user1, 'Here, have some spam.');

        // Retrieve the list of blocked users.
        $this->setUser($user1);
        $blockedusers = core_message_external::get_blocked_users($user1->id);
        $blockedusers = external_api::clean_returnvalue(core_message_external::get_blocked_users_returns(), $blockedusers);
        $this->assertCount(0, $blockedusers['users']);

        // Block the $userblocked and retrieve again the list.
        core_message_external::block_contacts(array($userblocked->id));
        $blockedusers = core_message_external::get_blocked_users($user1->id);
        $blockedusers = external_api::clean_returnvalue(core_message_external::get_blocked_users_returns(), $blockedusers);
        $this->assertCount(1, $blockedusers['users']);

        // Remove the $userblocked and check that the list now is empty.
        delete_user($userblocked);
        $blockedusers = core_message_external::get_blocked_users($user1->id);
        $blockedusers = external_api::clean_returnvalue(core_message_external::get_blocked_users_returns(), $blockedusers);
        $this->assertCount(0, $blockedusers['users']);

    }

    /**
     * Test mark_message_read.
     */
    public function test_mark_message_read() {
        $this->resetAfterTest(true);

        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();

        // Login as user1.
        $this->setUser($user1);
        $this->assertEquals(array(), core_message_external::create_contacts(
            array($user2->id, $user3->id)));

        // The user2 sends a couple of messages to user1.
        $this->send_message($user2, $user1, 'Hello there!');
        $this->send_message($user2, $user1, 'How you goin?');
        $this->send_message($user3, $user1, 'How you goin?');
        $this->send_message($user3, $user2, 'How you goin?');

        // Retrieve all messages sent by user2 (they are currently unread).
        $lastmessages = message_get_messages($user1->id, $user2->id, 0, false);

        $messageids = array();
        foreach ($lastmessages as $m) {
            $messageid = core_message_external::mark_message_read($m->id, time());
            $messageids[] = external_api::clean_returnvalue(core_message_external::mark_message_read_returns(), $messageid);
        }

        // Retrieve all messages sent (they are currently read).
        $lastmessages = message_get_messages($user1->id, $user2->id, 0, true);
        $this->assertCount(2, $lastmessages);
        $this->assertArrayHasKey($messageids[0]['messageid'], $lastmessages);
        $this->assertArrayHasKey($messageids[1]['messageid'], $lastmessages);

        // Retrieve all messages sent by any user (that are currently unread).
        $lastmessages = message_get_messages($user1->id, 0, 0, false);
        $this->assertCount(1, $lastmessages);

        // Invalid message ids.
        try {
            $messageid = core_message_external::mark_message_read($messageids[0]['messageid'] * 2, time());
            $this->fail('Exception expected due invalid messageid.');
        } catch (dml_missing_record_exception $e) {
            $this->assertEquals('invalidrecord', $e->errorcode);
        }

        // A message to a different user.
        $lastmessages = message_get_messages($user2->id, $user3->id, 0, false);
        $messageid = array_pop($lastmessages)->id;
        try {
            $messageid = core_message_external::mark_message_read($messageid, time());
            $this->fail('Exception expected due invalid messageid.');
        } catch (invalid_parameter_exception $e) {
            $this->assertEquals('invalidparameter', $e->errorcode);
        }

    }

    /**
     * Test delete_message.
     */
    public function test_delete_message() {
        global $DB;
        $this->resetAfterTest(true);

        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();
        $user4 = self::getDataGenerator()->create_user();

        // Login as user1.
        $this->setUser($user1);
        $this->assertEquals(array(), core_message_external::create_contacts(array($user2->id, $user3->id)));

        // User user1 does not interchange messages with user3.
        $m1to2 = message_post_message($user1, $user2, 'some random text 1', FORMAT_MOODLE);
        $m2to3 = message_post_message($user2, $user3, 'some random text 3', FORMAT_MOODLE);
        $m3to2 = message_post_message($user3, $user2, 'some random text 4', FORMAT_MOODLE);
        $m3to4 = message_post_message($user3, $user4, 'some random text 4', FORMAT_MOODLE);

        // Retrieve all messages sent by user2 (they are currently unread).
        $lastmessages = message_get_messages($user1->id, $user2->id, 0, false);

        // Delete a message not read, as a user from.
        $result = core_message_external::delete_message($m1to2, $user1->id, false);
        $result = external_api::clean_returnvalue(core_message_external::delete_message_returns(), $result);
        $this->assertTrue($result['status']);
        $this->assertCount(0, $result['warnings']);
        $deletedmessage = $DB->get_record('message', array('id' => $m1to2));
        $this->assertNotEquals(0, $deletedmessage->timeuserfromdeleted);

        // Try to delete the same message again.
        $result = core_message_external::delete_message($m1to2, $user1->id, false);
        $result = external_api::clean_returnvalue(core_message_external::delete_message_returns(), $result);
        $this->assertFalse($result['status']);

        // Try to delete a message that does not belong to me.
        try {
            $messageid = core_message_external::delete_message($m2to3, $user3->id, false);
            $this->fail('Exception expected due invalid messageid.');
        } catch (moodle_exception $e) {
            $this->assertEquals('You do not have permission to delete this message', $e->errorcode);
        }

        $this->setUser($user3);
        // Delete a message not read, as a user to.
        $result = core_message_external::delete_message($m2to3, $user3->id, false);
        $result = external_api::clean_returnvalue(core_message_external::delete_message_returns(), $result);
        $this->assertTrue($result['status']);
        $this->assertCount(0, $result['warnings']);
        $deletedmessage = $DB->get_record('message', array('id' => $m2to3));
        $this->assertNotEquals(0, $deletedmessage->timeusertodeleted);

        // Delete a message read.
        $message = $DB->get_record('message', array('id' => $m3to2));
        $messageid = message_mark_message_read($message, time());
        $result = core_message_external::delete_message($messageid, $user3->id);
        $result = external_api::clean_returnvalue(core_message_external::delete_message_returns(), $result);
        $this->assertTrue($result['status']);
        $this->assertCount(0, $result['warnings']);
        $deletedmessage = $DB->get_record('message_read', array('id' => $messageid));
        $this->assertNotEquals(0, $deletedmessage->timeuserfromdeleted);

        // Invalid message ids.
        try {
            $result = core_message_external::delete_message(-1, $user1->id);
            $this->fail('Exception expected due invalid messageid.');
        } catch (dml_missing_record_exception $e) {
            $this->assertEquals('invalidrecord', $e->errorcode);
        }

        // Invalid user.
        try {
            $result = core_message_external::delete_message($m1to2, -1, false);
            $this->fail('Exception expected due invalid user.');
        } catch (moodle_exception $e) {
            $this->assertEquals('invaliduser', $e->errorcode);
        }

        // Not active user.
        delete_user($user2);
        try {
            $result = core_message_external::delete_message($m1to2, $user2->id, false);
            $this->fail('Exception expected due invalid user.');
        } catch (moodle_exception $e) {
            $this->assertEquals('userdeleted', $e->errorcode);
        }

        // Now, as an admin, try to delete any message.
        $this->setAdminUser();
        $result = core_message_external::delete_message($m3to4, $user4->id, false);
        $result = external_api::clean_returnvalue(core_message_external::delete_message_returns(), $result);
        $this->assertTrue($result['status']);
        $this->assertCount(0, $result['warnings']);
        $deletedmessage = $DB->get_record('message', array('id' => $m3to4));
        $this->assertNotEquals(0, $deletedmessage->timeusertodeleted);

    }

    public function test_mark_all_notifications_as_read_invalid_user_exception() {
        $this->resetAfterTest(true);

        $this->expectException('moodle_exception');
        core_message_external::mark_all_notifications_as_read(-2132131, 0);
    }

    public function test_mark_all_notifications_as_read_access_denied_exception() {
        $this->resetAfterTest(true);

        $sender = $this->getDataGenerator()->create_user();
        $user = $this->getDataGenerator()->create_user();

        $this->setUser($user);
        $this->expectException('moodle_exception');
        core_message_external::mark_all_notifications_as_read($sender->id, 0);
    }

    public function test_mark_all_notifications_as_read_missing_from_user_exception() {
        $this->resetAfterTest(true);

        $sender = $this->getDataGenerator()->create_user();

        $this->setUser($sender);
        $this->expectException('moodle_exception');
        core_message_external::mark_all_notifications_as_read($sender->id, 99999);
    }

    public function test_mark_all_notifications_as_read() {
        global $DB;

        $this->resetAfterTest(true);

        $sender1 = $this->getDataGenerator()->create_user();
        $sender2 = $this->getDataGenerator()->create_user();
        $sender3 = $this->getDataGenerator()->create_user();
        $recipient = $this->getDataGenerator()->create_user();

        $this->setUser($recipient);

        $this->send_message($sender1, $recipient, 'Notification', 1);
        $this->send_message($sender1, $recipient, 'Notification', 1);
        $this->send_message($sender2, $recipient, 'Notification', 1);
        $this->send_message($sender2, $recipient, 'Notification', 1);
        $this->send_message($sender3, $recipient, 'Notification', 1);
        $this->send_message($sender3, $recipient, 'Notification', 1);

        core_message_external::mark_all_notifications_as_read($recipient->id, $sender1->id);
        $readnotifications = $DB->get_recordset('message_read', ['useridto' => $recipient->id]);
        $unreadnotifications = $DB->get_recordset('message', ['useridto' => $recipient->id]);

        $this->assertCount(2, $readnotifications);
        $this->assertCount(4, $unreadnotifications);

        core_message_external::mark_all_notifications_as_read($recipient->id, 0);
        $readnotifications = $DB->get_recordset('message_read', ['useridto' => $recipient->id]);
        $unreadnotifications = $DB->get_recordset('message', ['useridto' => $recipient->id]);

        $this->assertCount(6, $readnotifications);
        $this->assertCount(0, $unreadnotifications);
    }

    /**
     * Test get_user_notification_preferences
     */
    public function test_get_user_notification_preferences() {
        $this->resetAfterTest(true);

        $user = self::getDataGenerator()->create_user();
        $this->setUser($user);

        // Set a couple of preferences to test.
        set_user_preference('message_provider_mod_assign_assign_notification_loggedin', 'popup', $user);
        set_user_preference('message_provider_mod_assign_assign_notification_loggedoff', 'email', $user);

        $prefs = core_message_external::get_user_notification_preferences();
        $prefs = external_api::clean_returnvalue(core_message_external::get_user_notification_preferences_returns(), $prefs);
        // Check processors.
        $this->assertGreaterThanOrEqual(2, count($prefs['preferences']['processors']));
        $this->assertEquals($user->id, $prefs['preferences']['userid']);

        // Check components.
        $this->assertGreaterThanOrEqual(8, count($prefs['preferences']['components']));

        // Check some preferences that we previously set.
        $found = 0;
        foreach ($prefs['preferences']['components'] as $component) {
            foreach ($component['notifications'] as $prefdata) {
                if ($prefdata['preferencekey'] != 'message_provider_mod_assign_assign_notification') {
                    continue;
                }
                foreach ($prefdata['processors'] as $processor) {
                    if ($processor['name'] == 'popup') {
                        $this->assertTrue($processor['loggedin']['checked']);
                        $found++;
                    } else if ($processor['name'] == 'email') {
                        $this->assertTrue($processor['loggedoff']['checked']);
                        $found++;
                    }
                }
            }
        }
        $this->assertEquals(2, $found);
    }

    /**
     * Test get_user_notification_preferences permissions
     */
    public function test_get_user_notification_preferences_permissions() {
        $this->resetAfterTest(true);

        $user = self::getDataGenerator()->create_user();
        $otheruser = self::getDataGenerator()->create_user();
        $this->setUser($user);

        $this->expectException('moodle_exception');
        $prefs = core_message_external::get_user_notification_preferences($otheruser->id);
    }

    /**
     * Tests searching users in a course.
     */
    public function test_messagearea_search_users_in_course() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = new stdClass();
        $user1->firstname = 'User';
        $user1->lastname = 'One';
        $user1 = self::getDataGenerator()->create_user($user1);

        // The person doing the search.
        $this->setUser($user1);

        // Set the second user's status to online by setting their last access to now.
        $user2 = new stdClass();
        $user2->firstname = 'User';
        $user2->lastname = 'Two';
        $user2->lastaccess = time();
        $user2 = self::getDataGenerator()->create_user($user2);

        // Block the second user.
        message_block_contact($user2->id, $user1->id);

        $user3 = new stdClass();
        $user3->firstname = 'User';
        $user3->lastname = 'Three';
        $user3 = self::getDataGenerator()->create_user($user3);

        // Create a course.
        $course1 = new stdClass();
        $course1->fullname = 'Course';
        $course1->shortname = 'One';
        $course1 = $this->getDataGenerator()->create_course();

        // Enrol the user we are doing the search for and one user in the course.
        $this->getDataGenerator()->enrol_user($user1->id, $course1->id);
        $this->getDataGenerator()->enrol_user($user2->id, $course1->id);

        // Perform a search.
        $result = core_message_external::data_for_messagearea_search_users_in_course($user1->id, $course1->id, 'User');

        // We need to execute the return values cleaning process to simulate the web service.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_search_users_in_course_returns(),
            $result);

        // Check that we only retrieved a user that was enrolled, and that the user performing the search was not returned.
        $users = $result['contacts'];
        $this->assertCount(1, $users);

        $user = $users[0];
        $this->assertEquals($user2->id, $user['userid']);
        $this->assertEquals(fullname($user2), $user['fullname']);
        $this->assertFalse($user['ismessaging']);
        $this->assertFalse($user['sentfromcurrentuser']);
        $this->assertNull($user['lastmessage']);
        $this->assertNull($user['messageid']);
        $this->assertNull($user['isonline']);
        $this->assertFalse($user['isread']);
        $this->assertTrue($user['isblocked']);
        $this->assertNull($user['unreadcount']);
    }

    /**
     * Tests searching users in course as another user.
     */
    public function test_messagearea_search_users_in_course_as_other_user() {
        $this->resetAfterTest(true);

        // The person doing the search for another user.
        $this->setAdminUser();

        // Create some users.
        $user1 = new stdClass();
        $user1->firstname = 'User';
        $user1->lastname = 'One';
        $user1 = self::getDataGenerator()->create_user($user1);

        $user2 = new stdClass();
        $user2->firstname = 'User';
        $user2->lastname = 'Two';
        $user2 = self::getDataGenerator()->create_user($user2);

        $user3 = new stdClass();
        $user3->firstname = 'User';
        $user3->lastname = 'Three';
        $user3 = self::getDataGenerator()->create_user($user3);

        // Create a course.
        $course1 = new stdClass();
        $course1->fullname = 'Course';
        $course1->shortname = 'One';
        $course1 = $this->getDataGenerator()->create_course();

        // Enrol the user we are doing the search for and one user in the course.
        $this->getDataGenerator()->enrol_user($user1->id, $course1->id);
        $this->getDataGenerator()->enrol_user($user2->id, $course1->id);

        // Perform a search.
        $result = core_message_external::data_for_messagearea_search_users_in_course($user1->id, $course1->id, 'User');

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_search_users_in_course_returns(),
            $result);

        // Check that we got the user enrolled, and that the user we are performing the search on behalf of was not returned.
        $users = $result['contacts'];
        $this->assertCount(1, $users);

        $user = $users[0];
        $this->assertEquals($user2->id, $user['userid']);
        $this->assertEquals(fullname($user2), $user['fullname']);
        $this->assertFalse($user['ismessaging']);
        $this->assertFalse($user['sentfromcurrentuser']);
        $this->assertNull($user['lastmessage']);
        $this->assertNull($user['messageid']);
        $this->assertFalse($user['isonline']);
        $this->assertFalse($user['isread']);
        $this->assertFalse($user['isblocked']);
        $this->assertNull($user['unreadcount']);
    }

    /**
     * Tests searching users in course as another user without the proper capabilities.
     */
    public function test_messagearea_search_users_in_course_as_other_user_without_cap() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person doing the search for another user.
        $this->setUser($user1);

        // Create a course.
        $course = $this->getDataGenerator()->create_course();

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_search_users_in_course($user2->id, $course->id, 'User');
    }

    /**
     * Tests searching users in course with messaging disabled.
     */
    public function test_messagearea_search_users_in_course_messaging_disabled() {
        global $CFG;

        $this->resetAfterTest(true);

        // Create some skeleton data just so we can call the WS..
        $user = self::getDataGenerator()->create_user();
        $course = $this->getDataGenerator()->create_course();

        // The person doing the search for another user.
        $this->setUser($user);

        // Disable messaging.
        $CFG->messaging = 0;

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_search_users_in_course($user->id, $course->id, 'User');
    }

    /**
     * Tests searching users.
     */
    public function test_messagearea_search_users() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = new stdClass();
        $user1->firstname = 'User';
        $user1->lastname = 'One';
        $user1 = self::getDataGenerator()->create_user($user1);

        // Set as the user performing the search.
        $this->setUser($user1);

        $user2 = new stdClass();
        $user2->firstname = 'User search';
        $user2->lastname = 'Two';
        $user2 = self::getDataGenerator()->create_user($user2);

        $user3 = new stdClass();
        $user3->firstname = 'User search';
        $user3->lastname = 'Three';
        $user3 = self::getDataGenerator()->create_user($user3);

        $user4 = new stdClass();
        $user4->firstname = 'User';
        $user4->lastname = 'Four';
        $user4 = self::getDataGenerator()->create_user($user4);

        $user5 = new stdClass();
        $user5->firstname = 'User search';
        $user5->lastname = 'Five';
        $user5 = self::getDataGenerator()->create_user($user5);

        $user6 = new stdClass();
        $user6->firstname = 'User';
        $user6->lastname = 'Six';
        $user6 = self::getDataGenerator()->create_user($user6);

        // Create some courses.
        $course1 = new stdClass();
        $course1->fullname = 'Course search';
        $course1->shortname = 'One';
        $course1 = $this->getDataGenerator()->create_course($course1);

        $course2 = new stdClass();
        $course2->fullname = 'Course';
        $course2->shortname = 'Two';
        $course2 = $this->getDataGenerator()->create_course($course2);

        $course3 = new stdClass();
        $course3->fullname = 'Course';
        $course3->shortname = 'Three search';
        $course3 = $this->getDataGenerator()->create_course($course3);

        $course4 = new stdClass();
        $course4->fullname = 'Course Four';
        $course4->shortname = 'CF100';
        $course4 = $this->getDataGenerator()->create_course($course4);

        $this->getDataGenerator()->enrol_user($user1->id, $course1->id, 'student');
        $this->getDataGenerator()->enrol_user($user1->id, $course2->id, 'student');
        $this->getDataGenerator()->enrol_user($user1->id, $course3->id, 'student');

        // Add some users as contacts.
        message_add_contact($user2->id, 0, $user1->id);
        message_add_contact($user3->id, 0, $user1->id);
        message_add_contact($user4->id, 0, $user1->id);

        // Perform a search.
        $result = core_message_external::data_for_messagearea_search_users($user1->id, 'search');

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_search_users_returns(),
            $result);

        // Confirm that we returns contacts, courses and non-contacts.
        $contacts = $result['contacts'];
        $courses = $result['courses'];
        $noncontacts = $result['noncontacts'];

        // Check that we retrieved the correct contacts.
        $this->assertCount(2, $contacts);
        $this->assertEquals($user3->id, $contacts[0]['userid']);
        $this->assertEquals($user2->id, $contacts[1]['userid']);

        // Check that we retrieved the correct courses.
        $this->assertCount(2, $courses);
        $this->assertEquals($course3->id, $courses[0]['id']);
        $this->assertEquals($course1->id, $courses[1]['id']);

        // Check that we retrieved the correct non-contacts.
        $this->assertCount(1, $noncontacts);
        $this->assertEquals($user5->id, $noncontacts[0]['userid']);
    }

    /**
     * Tests searching users as another user.
     */
    public function test_messagearea_search_users_as_other_user() {
        $this->resetAfterTest(true);

        // The person doing the search.
        $this->setAdminUser();

        // Create some users.
        $user1 = new stdClass();
        $user1->firstname = 'User';
        $user1->lastname = 'One';
        $user1 = self::getDataGenerator()->create_user($user1);

        $user2 = new stdClass();
        $user2->firstname = 'User search';
        $user2->lastname = 'Two';
        $user2 = self::getDataGenerator()->create_user($user2);

        $user3 = new stdClass();
        $user3->firstname = 'User search';
        $user3->lastname = 'Three';
        $user3 = self::getDataGenerator()->create_user($user3);

        $user4 = new stdClass();
        $user4->firstname = 'User';
        $user4->lastname = 'Four';
        $user4 = self::getDataGenerator()->create_user($user4);

        $user5 = new stdClass();
        $user5->firstname = 'User search';
        $user5->lastname = 'Five';
        $user5 = self::getDataGenerator()->create_user($user5);

        $user6 = new stdClass();
        $user6->firstname = 'User';
        $user6->lastname = 'Six';
        $user6 = self::getDataGenerator()->create_user($user6);

        // Create some courses.
        $course1 = new stdClass();
        $course1->fullname = 'Course search';
        $course1->shortname = 'One';
        $course1 = $this->getDataGenerator()->create_course($course1);

        $course2 = new stdClass();
        $course2->fullname = 'Course';
        $course2->shortname = 'Two';
        $course2 = $this->getDataGenerator()->create_course($course2);

        $course3 = new stdClass();
        $course3->fullname = 'Course';
        $course3->shortname = 'Three search';
        $course3 = $this->getDataGenerator()->create_course($course3);

        // Add some users as contacts.
        message_add_contact($user2->id, 0, $user1->id);
        message_add_contact($user3->id, 0, $user1->id);
        message_add_contact($user4->id, 0, $user1->id);

        // Perform a search.
        $result = core_message_external::data_for_messagearea_search_users($user1->id, 'search');

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_search_users_returns(),
            $result);

        // Confirm that we returns contacts, courses and non-contacts.
        $contacts = $result['contacts'];
        $courses = $result['courses'];
        $noncontacts = $result['noncontacts'];

        // Check that we retrieved the correct contacts.
        $this->assertCount(2, $contacts);
        $this->assertEquals($user3->id, $contacts[0]['userid']);
        $this->assertEquals($user2->id, $contacts[1]['userid']);

        // Check that we retrieved the correct courses.
        $this->assertCount(0, $courses);

        // Check that we retrieved the correct non-contacts.
        $this->assertCount(1, $noncontacts);
        $this->assertEquals($user5->id, $noncontacts[0]['userid']);
    }

    /**
     * Tests searching users as another user without the proper capabilities.
     */
    public function test_messagearea_search_users_as_other_user_without_cap() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person doing the search for another user.
        $this->setUser($user1);

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_search_users($user2->id, 'User');
    }

    /**
     * Tests searching users with messaging disabled.
     */
    public function test_messagearea_search_users_messaging_disabled() {
        global $CFG;

        $this->resetAfterTest(true);

        // Create some skeleton data just so we can call the WS.
        $user = self::getDataGenerator()->create_user();

        // The person doing the search.
        $this->setUser($user);

        // Disable messaging.
        $CFG->messaging = 0;

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_search_users($user->id, 'User');
    }

    /**
     * Tests searching messages.
     */
    public function test_messagearea_search_messages() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person doing the search.
        $this->setUser($user1);

        // Send some messages back and forth.
        $time = time();
        $this->send_message($user1, $user2, 'Yo!', 0, $time);
        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);

        // Perform a search.
        $result = core_message_external::data_for_messagearea_search_messages($user1->id, 'o');

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_search_messages_returns(),
            $result);

        // Confirm the data is correct.
        $messages = $result['contacts'];
        $this->assertCount(2, $messages);

        $message1 = $messages[0];
        $message2 = $messages[1];

        $this->assertEquals($user2->id, $message1['userid']);
        $this->assertEquals(fullname($user2), $message1['fullname']);
        $this->assertTrue($message1['ismessaging']);
        $this->assertFalse($message1['sentfromcurrentuser']);
        $this->assertEquals('Word.', $message1['lastmessage']);
        $this->assertNotEmpty($message1['messageid']);
        $this->assertNull($message1['isonline']);
        $this->assertFalse($message1['isread']);
        $this->assertFalse($message1['isblocked']);
        $this->assertNull($message1['unreadcount']);

        $this->assertEquals($user2->id, $message2['userid']);
        $this->assertEquals(fullname($user2), $message2['fullname']);
        $this->assertTrue($message2['ismessaging']);
        $this->assertTrue($message2['sentfromcurrentuser']);
        $this->assertEquals('Yo!', $message2['lastmessage']);
        $this->assertNotEmpty($message2['messageid']);
        $this->assertNull($message2['isonline']);
        $this->assertTrue($message2['isread']);
        $this->assertFalse($message2['isblocked']);
        $this->assertNull($message2['unreadcount']);
    }

    /**
     * Tests searching messages as another user.
     */
    public function test_messagearea_search_messages_as_other_user() {
        $this->resetAfterTest(true);

        // The person doing the search.
        $this->setAdminUser();

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // Send some messages back and forth.
        $time = time();
        $this->send_message($user1, $user2, 'Yo!', 0, $time);
        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);

        // Perform a search.
        $result = core_message_external::data_for_messagearea_search_messages($user1->id, 'o');

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_search_messages_returns(),
            $result);

        // Confirm the data is correct.
        $messages = $result['contacts'];
        $this->assertCount(2, $messages);

        $message1 = $messages[0];
        $message2 = $messages[1];

        $this->assertEquals($user2->id, $message1['userid']);
        $this->assertEquals(fullname($user2), $message1['fullname']);
        $this->assertTrue($message1['ismessaging']);
        $this->assertFalse($message1['sentfromcurrentuser']);
        $this->assertEquals('Word.', $message1['lastmessage']);
        $this->assertNotEmpty($message1['messageid']);
        $this->assertFalse($message1['isonline']);
        $this->assertFalse($message1['isread']);
        $this->assertFalse($message1['isblocked']);
        $this->assertNull($message1['unreadcount']);

        $this->assertEquals($user2->id, $message2['userid']);
        $this->assertEquals(fullname($user2), $message2['fullname']);
        $this->assertTrue($message2['ismessaging']);
        $this->assertTrue($message2['sentfromcurrentuser']);
        $this->assertEquals('Yo!', $message2['lastmessage']);
        $this->assertNotEmpty($message2['messageid']);
        $this->assertFalse($message2['isonline']);
        $this->assertTrue($message2['isread']);
        $this->assertFalse($message2['isblocked']);
        $this->assertNull($message2['unreadcount']);
    }

    /**
     * Tests searching messages as another user without the proper capabilities.
     */
    public function test_messagearea_search_messages_as_other_user_without_cap() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person doing the search for another user.
        $this->setUser($user1);

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_search_messages($user2->id, 'Search');
    }

    /**
     * Tests searching messages with messaging disabled
     */
    public function test_messagearea_search_messages_messaging_disabled() {
        global $CFG;

        $this->resetAfterTest(true);

        // Create some skeleton data just so we can call the WS.
        $user = self::getDataGenerator()->create_user();

        // The person doing the search .
        $this->setUser($user);

        // Disable messaging.
        $CFG->messaging = 0;

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_search_messages($user->id, 'Search');
    }

    /**
     * Tests retrieving conversations.
     */
    public function test_messagearea_conversations() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();
        $user4 = self::getDataGenerator()->create_user();

        // The person retrieving the conversations.
        $this->setUser($user1);

        // Send some messages back and forth, have some different conversations with different users.
        $time = time();
        $this->send_message($user1, $user2, 'Yo!', 0, $time);
        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);

        $this->send_message($user1, $user3, 'Booyah', 0, $time + 4);
        $this->send_message($user3, $user1, 'Whaaat?', 0, $time + 5);
        $this->send_message($user1, $user3, 'Nothing.', 0, $time + 6);
        $this->send_message($user3, $user1, 'Cool.', 0, $time + 7);

        $this->send_message($user1, $user4, 'Hey mate, you see the new messaging UI in Moodle?', 0, $time + 8);
        $this->send_message($user4, $user1, 'Yah brah, it\'s pretty rad.', 0, $time + 9);
        $this->send_message($user1, $user4, 'Dope.', 0, $time + 10);

        // Retrieve the conversations.
        $result = core_message_external::data_for_messagearea_conversations($user1->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_conversations_returns(),
            $result);

        // Confirm the data is correct.
        $messages = $result['contacts'];
        $this->assertCount(3, $messages);

        $message1 = $messages[0];
        $message2 = $messages[1];
        $message3 = $messages[2];

        $this->assertEquals($user4->id, $message1['userid']);
        $this->assertTrue($message1['ismessaging']);
        $this->assertTrue($message1['sentfromcurrentuser']);
        $this->assertEquals('Dope.', $message1['lastmessage']);
        $this->assertNull($message1['messageid']);
        $this->assertNull($message1['isonline']);
        $this->assertTrue($message1['isread']);
        $this->assertFalse($message1['isblocked']);
        $this->assertEquals(0, $message1['unreadcount']);

        $this->assertEquals($user3->id, $message2['userid']);
        $this->assertTrue($message2['ismessaging']);
        $this->assertFalse($message2['sentfromcurrentuser']);
        $this->assertEquals('Cool.', $message2['lastmessage']);
        $this->assertNull($message2['messageid']);
        $this->assertNull($message2['isonline']);
        $this->assertFalse($message2['isread']);
        $this->assertFalse($message2['isblocked']);
        $this->assertEquals(2, $message2['unreadcount']);

        $this->assertEquals($user2->id, $message3['userid']);
        $this->assertTrue($message3['ismessaging']);
        $this->assertFalse($message3['sentfromcurrentuser']);
        $this->assertEquals('Word.', $message3['lastmessage']);
        $this->assertNull($message3['messageid']);
        $this->assertNull($message3['isonline']);
        $this->assertFalse($message3['isread']);
        $this->assertFalse($message3['isblocked']);
        $this->assertEquals(2, $message3['unreadcount']);
    }

    /**
     * Tests retrieving conversations as another user.
     */
    public function test_messagearea_conversations_as_other_user() {
        $this->resetAfterTest(true);

        // Set as admin.
        $this->setAdminUser();

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();
        $user4 = self::getDataGenerator()->create_user();

        // Send some messages back and forth, have some different conversations with different users.
        $time = time();
        $this->send_message($user1, $user2, 'Yo!', 0, $time);
        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);

        $this->send_message($user1, $user3, 'Booyah', 0, $time + 4);
        $this->send_message($user3, $user1, 'Whaaat?', 0, $time + 5);
        $this->send_message($user1, $user3, 'Nothing.', 0, $time + 6);
        $this->send_message($user3, $user1, 'Cool.', 0, $time + 7);

        $this->send_message($user1, $user4, 'Hey mate, you see the new messaging UI in Moodle?', 0, $time + 8);
        $this->send_message($user4, $user1, 'Yah brah, it\'s pretty rad.', 0, $time + 9);
        $this->send_message($user1, $user4, 'Dope.', 0, $time + 10);

        // Retrieve the conversations.
        $result = core_message_external::data_for_messagearea_conversations($user1->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_conversations_returns(),
            $result);

        // Confirm the data is correct.
        $messages = $result['contacts'];
        $this->assertCount(3, $messages);

        $message1 = $messages[0];
        $message2 = $messages[1];
        $message3 = $messages[2];

        $this->assertEquals($user4->id, $message1['userid']);
        $this->assertTrue($message1['ismessaging']);
        $this->assertTrue($message1['sentfromcurrentuser']);
        $this->assertEquals('Dope.', $message1['lastmessage']);
        $this->assertNull($message1['messageid']);
        $this->assertFalse($message1['isonline']);
        $this->assertTrue($message1['isread']);
        $this->assertFalse($message1['isblocked']);
        $this->assertEquals(0, $message1['unreadcount']);

        $this->assertEquals($user3->id, $message2['userid']);
        $this->assertTrue($message2['ismessaging']);
        $this->assertFalse($message2['sentfromcurrentuser']);
        $this->assertEquals('Cool.', $message2['lastmessage']);
        $this->assertNull($message2['messageid']);
        $this->assertFalse($message2['isonline']);
        $this->assertFalse($message2['isread']);
        $this->assertFalse($message2['isblocked']);
        $this->assertEquals(2, $message2['unreadcount']);

        $this->assertEquals($user2->id, $message3['userid']);
        $this->assertTrue($message3['ismessaging']);
        $this->assertFalse($message3['sentfromcurrentuser']);
        $this->assertEquals('Word.', $message3['lastmessage']);
        $this->assertNull($message3['messageid']);
        $this->assertFalse($message3['isonline']);
        $this->assertFalse($message3['isread']);
        $this->assertFalse($message3['isblocked']);
        $this->assertEquals(2, $message3['unreadcount']);
    }

    /**
     * Tests retrieving conversations as another user without the proper capabilities.
     */
    public function test_messagearea_conversations_as_other_user_without_cap() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person retrieving the conversations for another user.
        $this->setUser($user1);

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_conversations($user2->id);
    }

    /**
     * Tests retrieving conversations with messaging disabled.
     */
    public function test_messagearea_conversations_messaging_disabled() {
        global $CFG;

        $this->resetAfterTest(true);

        // Create some skeleton data just so we can call the WS.
        $user = self::getDataGenerator()->create_user();

        // The person retrieving the conversations.
        $this->setUser($user);

        // Disable messaging.
        $CFG->messaging = 0;

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_conversations($user->id);
    }

    /**
     * Tests retrieving contacts.
     */
    public function test_messagearea_contacts() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();

        // Set as the user.
        $this->setUser($user1);

        $user2 = new stdClass();
        $user2->firstname = 'User';
        $user2->lastname = 'A';
        $user2 = self::getDataGenerator()->create_user($user2);

        $user3 = new stdClass();
        $user3->firstname = 'User';
        $user3->lastname = 'B';
        $user3 = self::getDataGenerator()->create_user($user3);

        $user4 = new stdClass();
        $user4->firstname = 'User';
        $user4->lastname = 'C';
        $user4 = self::getDataGenerator()->create_user($user4);

        $user5 = new stdClass();
        $user5->firstname = 'User';
        $user5->lastname = 'D';
        $user5 = self::getDataGenerator()->create_user($user5);

        // Add some users as contacts.
        message_add_contact($user2->id, 0, $user1->id);
        message_add_contact($user3->id, 0, $user1->id);
        message_add_contact($user4->id, 0, $user1->id);

        // Retrieve the contacts.
        $result = core_message_external::data_for_messagearea_contacts($user1->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_contacts_returns(),
            $result);

        // Confirm the data is correct.
        $contacts = $result['contacts'];
        $this->assertCount(3, $contacts);

        $contact1 = $contacts[0];
        $contact2 = $contacts[1];
        $contact3 = $contacts[2];

        $this->assertEquals($user2->id, $contact1['userid']);
        $this->assertFalse($contact1['ismessaging']);
        $this->assertFalse($contact1['sentfromcurrentuser']);
        $this->assertNull($contact1['lastmessage']);
        $this->assertNull($contact1['messageid']);
        $this->assertNull($contact1['isonline']);
        $this->assertFalse($contact1['isread']);
        $this->assertFalse($contact1['isblocked']);
        $this->assertNull($contact1['unreadcount']);

        $this->assertEquals($user3->id, $contact2['userid']);
        $this->assertFalse($contact2['ismessaging']);
        $this->assertFalse($contact2['sentfromcurrentuser']);
        $this->assertNull($contact2['lastmessage']);
        $this->assertNull($contact2['messageid']);
        $this->assertNull($contact2['isonline']);
        $this->assertFalse($contact2['isread']);
        $this->assertFalse($contact2['isblocked']);
        $this->assertNull($contact2['unreadcount']);

        $this->assertEquals($user4->id, $contact3['userid']);
        $this->assertFalse($contact3['ismessaging']);
        $this->assertFalse($contact3['sentfromcurrentuser']);
        $this->assertNull($contact3['lastmessage']);
        $this->assertNull($contact3['messageid']);
        $this->assertNull($contact3['isonline']);
        $this->assertFalse($contact3['isread']);
        $this->assertFalse($contact3['isblocked']);
        $this->assertNull($contact3['unreadcount']);
    }

    /**
     * Tests retrieving contacts as another user.
     */
    public function test_messagearea_contacts_as_other_user() {
        $this->resetAfterTest(true);

        $this->setAdminUser();

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();

        $user2 = new stdClass();
        $user2->firstname = 'User';
        $user2->lastname = 'A';
        $user2 = self::getDataGenerator()->create_user($user2);

        $user3 = new stdClass();
        $user3->firstname = 'User';
        $user3->lastname = 'B';
        $user3 = self::getDataGenerator()->create_user($user3);

        $user4 = new stdClass();
        $user4->firstname = 'User';
        $user4->lastname = 'C';
        $user4 = self::getDataGenerator()->create_user($user4);

        $user5 = new stdClass();
        $user5->firstname = 'User';
        $user5->lastname = 'D';
        $user5 = self::getDataGenerator()->create_user($user5);

        // Add some users as contacts.
        message_add_contact($user2->id, 0, $user1->id);
        message_add_contact($user3->id, 0, $user1->id);
        message_add_contact($user4->id, 0, $user1->id);

        // Retrieve the contacts.
        $result = core_message_external::data_for_messagearea_contacts($user1->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_contacts_returns(),
            $result);

        // Confirm the data is correct.
        $contacts = $result['contacts'];
        $this->assertCount(3, $contacts);

        $contact1 = $contacts[0];
        $contact2 = $contacts[1];
        $contact3 = $contacts[2];

        $this->assertEquals($user2->id, $contact1['userid']);
        $this->assertFalse($contact1['ismessaging']);
        $this->assertFalse($contact1['sentfromcurrentuser']);
        $this->assertNull($contact1['lastmessage']);
        $this->assertNull($contact1['messageid']);
        $this->assertFalse($contact1['isonline']);
        $this->assertFalse($contact1['isread']);
        $this->assertFalse($contact1['isblocked']);
        $this->assertNull($contact1['unreadcount']);

        $this->assertEquals($user3->id, $contact2['userid']);
        $this->assertFalse($contact2['ismessaging']);
        $this->assertFalse($contact2['sentfromcurrentuser']);
        $this->assertNull($contact2['lastmessage']);
        $this->assertNull($contact2['messageid']);
        $this->assertFalse($contact2['isonline']);
        $this->assertFalse($contact2['isread']);
        $this->assertFalse($contact2['isblocked']);
        $this->assertNull($contact2['unreadcount']);

        $this->assertEquals($user4->id, $contact3['userid']);
        $this->assertFalse($contact3['ismessaging']);
        $this->assertFalse($contact3['sentfromcurrentuser']);
        $this->assertNull($contact3['lastmessage']);
        $this->assertNull($contact3['messageid']);
        $this->assertFalse($contact3['isonline']);
        $this->assertFalse($contact3['isread']);
        $this->assertFalse($contact3['isblocked']);
        $this->assertNull($contact3['unreadcount']);
    }

    /**
     * Tests retrieving contacts as another user without the proper capabilities.
     */
    public function test_messagearea_contacts_as_other_user_without_cap() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person retrieving the contacts for another user.
        $this->setUser($user1);

        // Perform the WS call and ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_contacts($user2->id);
    }

    /**
     * Tests retrieving contacts with messaging disabled.
     */
    public function test_messagearea_contacts_messaging_disabled() {
        global $CFG;

        $this->resetAfterTest(true);

        // Create some skeleton data just so we can call the WS.
        $user = self::getDataGenerator()->create_user();

        // The person retrieving the contacts.
        $this->setUser($user);

        // Disable messaging.
        $CFG->messaging = 0;

        // Perform the WS call and ensure we are shown that it is disabled.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_contacts($user->id);
    }

    /**
     * Tests retrieving messages.
     */
    public function test_messagearea_messages() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person asking for the messages.
        $this->setUser($user1);

        // Send some messages back and forth.
        $time = time();
        $this->send_message($user1, $user2, 'Yo!', 0, $time);
        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);

        // Retrieve the messages.
        $result = core_message_external::data_for_messagearea_messages($user1->id, $user2->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_messages_returns(),
            $result);

        // Check the results are correct.
        $this->assertTrue($result['iscurrentuser']);
        $this->assertEquals($user1->id, $result['currentuserid']);
        $this->assertEquals($user2->id, $result['otheruserid']);
        $this->assertEquals(fullname($user2), $result['otheruserfullname']);
        $this->assertNull($result['isonline']);

        // Confirm the message data is correct.
        $messages = $result['messages'];
        $this->assertCount(4, $messages);

        $message1 = $messages[0];
        $message2 = $messages[1];
        $message3 = $messages[2];
        $message4 = $messages[3];

        $this->assertEquals($user1->id, $message1['useridfrom']);
        $this->assertEquals($user2->id, $message1['useridto']);
        $this->assertTrue($message1['displayblocktime']);
        $this->assertContains('Yo!', $message1['text']);

        $this->assertEquals($user2->id, $message2['useridfrom']);
        $this->assertEquals($user1->id, $message2['useridto']);
        $this->assertFalse($message2['displayblocktime']);
        $this->assertContains('Sup mang?', $message2['text']);

        $this->assertEquals($user1->id, $message3['useridfrom']);
        $this->assertEquals($user2->id, $message3['useridto']);
        $this->assertFalse($message3['displayblocktime']);
        $this->assertContains('Writing PHPUnit tests!', $message3['text']);

        $this->assertEquals($user2->id, $message4['useridfrom']);
        $this->assertEquals($user1->id, $message4['useridto']);
        $this->assertFalse($message4['displayblocktime']);
        $this->assertContains('Word.', $message4['text']);
    }

    /**
     * Tests retrieving messages.
     */
    public function test_messagearea_messages_timefrom() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person asking for the messages.
        $this->setUser($user1);

        // Send some messages back and forth.
        $time = time();
        $this->send_message($user1, $user2, 'Message 1', 0, $time - 4);
        $this->send_message($user2, $user1, 'Message 2', 0, $time - 3);
        $this->send_message($user1, $user2, 'Message 3', 0, $time - 2);
        $this->send_message($user2, $user1, 'Message 4', 0, $time - 1);

        // Retrieve the messages from $time - 3, which should be the 3 most recent messages.
        $result = core_message_external::data_for_messagearea_messages($user1->id, $user2->id, 0, 0, false, $time - 3);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_messages_returns(),
            $result);

        // Confirm the message data is correct. We shouldn't get 'Message 1' back.
        $messages = $result['messages'];
        $this->assertCount(3, $messages);

        $message1 = $messages[0];
        $message2 = $messages[1];
        $message3 = $messages[2];

        $this->assertContains('Message 2', $message1['text']);
        $this->assertContains('Message 3', $message2['text']);
        $this->assertContains('Message 4', $message3['text']);
    }

    /**
     * Tests retrieving messages as another user.
     */
    public function test_messagearea_messages_as_other_user() {
        $this->resetAfterTest(true);

        // Set as admin.
        $this->setAdminUser();

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // Send some messages back and forth.
        $time = time();
        $this->send_message($user1, $user2, 'Yo!', 0, $time);
        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);

        // Retrieve the messages.
        $result = core_message_external::data_for_messagearea_messages($user1->id, $user2->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_messages_returns(),
            $result);

        // Check the results are correct.
        $this->assertFalse($result['iscurrentuser']);
        $this->assertEquals($user1->id, $result['currentuserid']);
        $this->assertEquals($user2->id, $result['otheruserid']);
        $this->assertEquals(fullname($user2), $result['otheruserfullname']);
        $this->assertFalse($result['isonline']);

        // Confirm the message data is correct.
        $messages = $result['messages'];
        $this->assertCount(4, $messages);

        $message1 = $messages[0];
        $message2 = $messages[1];
        $message3 = $messages[2];
        $message4 = $messages[3];

        $this->assertEquals($user1->id, $message1['useridfrom']);
        $this->assertEquals($user2->id, $message1['useridto']);
        $this->assertTrue($message1['displayblocktime']);
        $this->assertContains('Yo!', $message1['text']);

        $this->assertEquals($user2->id, $message2['useridfrom']);
        $this->assertEquals($user1->id, $message2['useridto']);
        $this->assertFalse($message2['displayblocktime']);
        $this->assertContains('Sup mang?', $message2['text']);

        $this->assertEquals($user1->id, $message3['useridfrom']);
        $this->assertEquals($user2->id, $message3['useridto']);
        $this->assertFalse($message3['displayblocktime']);
        $this->assertContains('Writing PHPUnit tests!', $message3['text']);

        $this->assertEquals($user2->id, $message4['useridfrom']);
        $this->assertEquals($user1->id, $message4['useridto']);
        $this->assertFalse($message4['displayblocktime']);
        $this->assertContains('Word.', $message4['text']);
    }

    /**
     * Tests retrieving messages as another user without the proper capabilities.
     */
    public function test_messagearea_messages_as_other_user_without_cap() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();

        // The person asking for the messages for another user.
        $this->setUser($user1);

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_messages($user2->id, $user3->id);
    }

    /**
     * Tests retrieving messages with messaging disabled.
     */
    public function test_messagearea_messages_messaging_disabled() {
        global $CFG;

        $this->resetAfterTest(true);

        // Create some skeleton data just so we can call the WS.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person asking for the messages for another user.
        $this->setUser($user1);

        // Disable messaging.
        $CFG->messaging = 0;

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_messages($user1->id, $user2->id);
    }

    /**
     * Tests retrieving most recent message.
     */
    public function test_messagearea_get_most_recent_message() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person doing the search.
        $this->setUser($user1);

        // Send some messages back and forth.
        $time = time();
        $this->send_message($user1, $user2, 'Yo!', 0, $time);
        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);

        // Get the most recent message.
        $result = core_message_external::data_for_messagearea_get_most_recent_message($user1->id, $user2->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_get_most_recent_message_returns(),
            $result);

        // Check the results are correct.
        $this->assertEquals($user2->id, $result['useridfrom']);
        $this->assertEquals($user1->id, $result['useridto']);
        $this->assertContains('Word.', $result['text']);
    }

    /**
     * Tests retrieving most recent message as another user.
     */
    public function test_messagearea_get_most_recent_message_as_other_user() {
        $this->resetAfterTest(true);

        // The person doing the search.
        $this->setAdminUser();

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // Send some messages back and forth.
        $time = time();
        $this->send_message($user1, $user2, 'Yo!', 0, $time);
        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);

        // Get the most recent message.
        $result = core_message_external::data_for_messagearea_get_most_recent_message($user1->id, $user2->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_get_most_recent_message_returns(),
            $result);

        // Check the results are correct.
        $this->assertEquals($user2->id, $result['useridfrom']);
        $this->assertEquals($user1->id, $result['useridto']);
        $this->assertContains('Word.', $result['text']);
    }

    /**
     * Tests retrieving most recent message as another user without the proper capabilities.
     */
    public function test_messagearea_get_most_recent_message_as_other_user_without_cap() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();

        // The person asking for the most recent message for another user.
        $this->setUser($user1);

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_get_most_recent_message($user2->id, $user3->id);
    }

    /**
     * Tests retrieving most recent message with messaging disabled.
     */
    public function test_messagearea_get_most_recent_message_messaging_disabled() {
        global $CFG;

        $this->resetAfterTest(true);

        // Create some skeleton data just so we can call the WS.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person asking for the most recent message.
        $this->setUser($user1);

        // Disable messaging.
        $CFG->messaging = 0;

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_get_most_recent_message($user1->id, $user2->id);
    }

    /**
     * Tests retrieving a user's profile.
     */
    public function test_messagearea_get_profile() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person asking for the profile information.
        $this->setUser($user1);

        // Get the profile.
        $result = core_message_external::data_for_messagearea_get_profile($user1->id, $user2->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_get_profile_returns(),
            $result);

        $this->assertEquals($user2->id, $result['userid']);
        $this->assertEmpty($result['email']);
        $this->assertEmpty($result['country']);
        $this->assertEmpty($result['city']);
        $this->assertEquals(fullname($user2), $result['fullname']);
        $this->assertNull($result['isonline']);
        $this->assertFalse($result['isblocked']);
        $this->assertFalse($result['iscontact']);
    }

    /**
     * Tests retrieving a user's profile as another user.
     */
    public function test_messagearea_profile_as_other_user() {
        $this->resetAfterTest(true);

        // The person asking for the profile information.
        $this->setAdminUser();

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();

        $user2 = new stdClass();
        $user2->country = 'AU';
        $user2->city = 'Perth';
        $user2 = self::getDataGenerator()->create_user($user2);

        // Get the profile.
        $result = core_message_external::data_for_messagearea_get_profile($user1->id, $user2->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::data_for_messagearea_get_profile_returns(),
            $result);

        $this->assertEquals($user2->id, $result['userid']);
        $this->assertEquals($user2->email, $result['email']);
        $this->assertEquals(get_string($user2->country, 'countries'), $result['country']);
        $this->assertEquals($user2->city, $result['city']);
        $this->assertEquals(fullname($user2), $result['fullname']);
        $this->assertFalse($result['isonline']);
        $this->assertFalse($result['isblocked']);
        $this->assertFalse($result['iscontact']);
    }

    /**
     * Tests retrieving a user's profile as another user without the proper capabilities.
     */
    public function test_messagearea_profile_as_other_user_without_cap() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();

        // The person asking for the profile information for another user.
        $this->setUser($user1);

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_get_profile($user2->id, $user3->id);
    }

    /**
     * Tests retrieving a user's profile with messaging disabled.
     */
    public function test_messagearea_profile_messaging_disabled() {
        global $CFG;

        $this->resetAfterTest(true);

        // Create some skeleton data just so we can call the WS.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person asking for the profile information.
        $this->setUser($user1);

        // Disable messaging.
        $CFG->messaging = 0;

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::data_for_messagearea_get_profile($user1->id, $user2->id);
    }

    /**
     * Test marking all message as read with an invalid user.
     */
    public function test_mark_all_messages_as_read_invalid_user_exception() {
        $this->resetAfterTest(true);

        $this->expectException('moodle_exception');
        core_message_external::mark_all_messages_as_read(-2132131, 0);
    }

    /**
     * Test marking all message as read without proper access.
     */
    public function test_mark_all_messages_as_read_access_denied_exception() {
        $this->resetAfterTest(true);

        $sender = $this->getDataGenerator()->create_user();
        $user = $this->getDataGenerator()->create_user();

        $this->setUser($user);
        $this->expectException('moodle_exception');
        core_message_external::mark_all_messages_as_read($sender->id, 0);
    }

    /**
     * Test marking all message as read with missing from user.
     */
    public function test_mark_all_messages_as_read_missing_from_user_exception() {
        $this->resetAfterTest(true);

        $sender = $this->getDataGenerator()->create_user();

        $this->setUser($sender);
        $this->expectException('moodle_exception');
        core_message_external::mark_all_messages_as_read($sender->id, 99999);
    }

    /**
     * Test marking all message as read.
     */
    public function test_mark_all_messages_as_read() {
        global $DB;

        $this->resetAfterTest(true);

        $sender1 = $this->getDataGenerator()->create_user();
        $sender2 = $this->getDataGenerator()->create_user();
        $sender3 = $this->getDataGenerator()->create_user();
        $recipient = $this->getDataGenerator()->create_user();

        $this->setUser($recipient);

        $this->send_message($sender1, $recipient, 'Message');
        $this->send_message($sender1, $recipient, 'Message');
        $this->send_message($sender2, $recipient, 'Message');
        $this->send_message($sender2, $recipient, 'Message');
        $this->send_message($sender3, $recipient, 'Message');
        $this->send_message($sender3, $recipient, 'Message');

        core_message_external::mark_all_messages_as_read($recipient->id, $sender1->id);
        $readnotifications = $DB->get_records('message_read', array('useridto' => $recipient->id));
        $unreadnotifications = $DB->get_records('message', array('useridto' => $recipient->id));

        $this->assertCount(2, $readnotifications);
        $this->assertCount(4, $unreadnotifications);

        core_message_external::mark_all_messages_as_read($recipient->id, 0);
        $readnotifications = $DB->get_records('message_read', array('useridto' => $recipient->id));
        $unreadnotifications = $DB->get_records('message', array('useridto' => $recipient->id));

        $this->assertCount(6, $readnotifications);
        $this->assertCount(0, $unreadnotifications);
    }

    /**
     * Test getting unread conversation count.
     */
    public function test_get_unread_conversations_count() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();
        $user4 = self::getDataGenerator()->create_user();

        // The person wanting the conversation count.
        $this->setUser($user1);

        // Send some messages back and forth, have some different conversations with different users.
        $this->send_message($user1, $user2, 'Yo!');
        $this->send_message($user2, $user1, 'Sup mang?');
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!');
        $this->send_message($user2, $user1, 'Word.');

        $this->send_message($user1, $user3, 'Booyah');
        $this->send_message($user3, $user1, 'Whaaat?');
        $this->send_message($user1, $user3, 'Nothing.');
        $this->send_message($user3, $user1, 'Cool.');

        $this->send_message($user1, $user4, 'Hey mate, you see the new messaging UI in Moodle?');
        $this->send_message($user4, $user1, 'Yah brah, it\'s pretty rad.');
        $this->send_message($user1, $user4, 'Dope.');

        // Get the unread conversation count.
        $result = core_message_external::get_unread_conversations_count($user1->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::get_unread_conversations_count_returns(),
            $result);

        $this->assertEquals(3, $result);
    }

    /**
     * Test getting unread conversation count as other user.
     */
    public function test_get_unread_conversations_count_as_other_user() {
        $this->resetAfterTest(true);

        // The person wanting the conversation count.
        $this->setAdminUser();

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();
        $user4 = self::getDataGenerator()->create_user();

        // Send some messages back and forth, have some different conversations with different users.
        $this->send_message($user1, $user2, 'Yo!');
        $this->send_message($user2, $user1, 'Sup mang?');
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!');
        $this->send_message($user2, $user1, 'Word.');

        $this->send_message($user1, $user3, 'Booyah');
        $this->send_message($user3, $user1, 'Whaaat?');
        $this->send_message($user1, $user3, 'Nothing.');
        $this->send_message($user3, $user1, 'Cool.');

        $this->send_message($user1, $user4, 'Hey mate, you see the new messaging UI in Moodle?');
        $this->send_message($user4, $user1, 'Yah brah, it\'s pretty rad.');
        $this->send_message($user1, $user4, 'Dope.');

        // Get the unread conversation count.
        $result = core_message_external::get_unread_conversations_count($user1->id);

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::get_unread_conversations_count_returns(),
            $result);

        $this->assertEquals(3, $result);
    }

    /**
     * Test getting unread conversation count as other user without proper capability.
     */
    public function test_get_unread_conversations_count_as_other_user_without_cap() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person wanting the conversation count.
        $this->setUser($user1);

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::get_unread_conversations_count($user2->id);
    }

    /**
     * Test deleting conversation.
     */
    public function test_delete_conversation() {
        global $DB;

        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person wanting to delete the conversation.
        $this->setUser($user1);

        // Send some messages back and forth.
        $time = time();
        $this->send_message($user1, $user2, 'Yo!', 0, $time);
        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);

        // Delete the conversation.
        core_message_external::delete_conversation($user1->id, $user2->id);

        $messages = $DB->get_records('message', array(), 'timecreated ASC');
        $this->assertCount(4, $messages);

        $message1 = array_shift($messages);
        $message2 = array_shift($messages);
        $message3 = array_shift($messages);
        $message4 = array_shift($messages);

        $this->assertNotEmpty($message1->timeuserfromdeleted);
        $this->assertEmpty($message1->timeusertodeleted);

        $this->assertEmpty($message2->timeuserfromdeleted);
        $this->assertNotEmpty($message2->timeusertodeleted);

        $this->assertNotEmpty($message3->timeuserfromdeleted);
        $this->assertEmpty($message3->timeusertodeleted);

        $this->assertEmpty($message4->timeuserfromdeleted);
        $this->assertNotEmpty($message4->timeusertodeleted);
    }

    /**
     * Test deleting conversation as other user.
     */
    public function test_delete_conversation_as_other_user() {
        global $DB;

        $this->resetAfterTest(true);

        $this->setAdminUser();

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // Send some messages back and forth.
        $time = time();
        $this->send_message($user1, $user2, 'Yo!', 0, $time);
        $this->send_message($user2, $user1, 'Sup mang?', 0, $time + 1);
        $this->send_message($user1, $user2, 'Writing PHPUnit tests!', 0, $time + 2);
        $this->send_message($user2, $user1, 'Word.', 0, $time + 3);

        // Delete the conversation.
        core_message_external::delete_conversation($user1->id, $user2->id);

        $messages = $DB->get_records('message', array(), 'timecreated ASC');
        $this->assertCount(4, $messages);

        $message1 = array_shift($messages);
        $message2 = array_shift($messages);
        $message3 = array_shift($messages);
        $message4 = array_shift($messages);

        $this->assertNotEmpty($message1->timeuserfromdeleted);
        $this->assertEmpty($message1->timeusertodeleted);

        $this->assertEmpty($message2->timeuserfromdeleted);
        $this->assertNotEmpty($message2->timeusertodeleted);

        $this->assertNotEmpty($message3->timeuserfromdeleted);
        $this->assertEmpty($message3->timeusertodeleted);

        $this->assertEmpty($message4->timeuserfromdeleted);
        $this->assertNotEmpty($message4->timeusertodeleted);
    }

    /**
     * Test deleting conversation as other user without proper capability.
     */
    public function test_delete_conversation_as_other_user_without_cap() {
        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();
        $user3 = self::getDataGenerator()->create_user();

        // The person wanting to delete the conversation.
        $this->setUser($user3);

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::delete_conversation($user1->id, $user2->id);
    }

    /**
     * Test deleting conversation with messaging disabled.
     */
    public function test_delete_conversation_messaging_disabled() {
        global $CFG;

        $this->resetAfterTest(true);

        // Create some users.
        $user1 = self::getDataGenerator()->create_user();
        $user2 = self::getDataGenerator()->create_user();

        // The person wanting to delete the conversation.
        $this->setUser($user1);

        // Disable messaging.
        $CFG->messaging = 0;

        // Ensure an exception is thrown.
        $this->expectException('moodle_exception');
        core_message_external::delete_conversation($user1->id, $user2->id);
    }

    /**
     * Test get message processor.
     */
    public function test_get_message_processor() {
        $this->resetAfterTest(true);

        // Create a user.
        $user1 = self::getDataGenerator()->create_user();

        // Set you as the user.
        $this->setUser($user1);

        // Get the message processors.
        $result = core_message_external::get_message_processor($user1->id, 'popup');

        // We need to execute the return values cleaning process to simulate the web service server.
        $result = external_api::clean_returnvalue(core_message_external::get_message_processor_returns(), $result);

        $this->assertNotEmpty($result['systemconfigured']);
        $this->assertNotEmpty($result['userconfigured']);
    }

    /**
     * Test get_user_notification_preferences
     */
    public function test_get_user_message_preferences() {
        $this->resetAfterTest(true);

        $user = self::getDataGenerator()->create_user();
        $this->setUser($user);

        // Set a couple of preferences to test.
        set_user_preference('message_provider_moodle_instantmessage_loggedin', 'email', $user);
        set_user_preference('message_provider_moodle_instantmessage_loggedoff', 'email', $user);
        set_user_preference('message_blocknoncontacts', 1, $user);

        $prefs = core_message_external::get_user_message_preferences();
        $prefs = external_api::clean_returnvalue(core_message_external::get_user_message_preferences_returns(), $prefs);
        $this->assertEquals($user->id, $prefs['preferences']['userid']);

        // Check components.
        $this->assertCount(1, $prefs['preferences']['components']);
        $this->assertTrue($prefs['blocknoncontacts']);

        // Check some preferences that we previously set.
        $found = false;
        foreach ($prefs['preferences']['components'] as $component) {
            foreach ($component['notifications'] as $prefdata) {
                if ($prefdata['preferencekey'] != 'message_provider_moodle_instantmessage') {
                    continue;
                }
                foreach ($prefdata['processors'] as $processor) {
                    if ($processor['name'] == 'email') {
                        $this->assertTrue($processor['loggedin']['checked']);
                        $this->assertTrue($processor['loggedoff']['checked']);
                        $found = true;
                    }
                }
            }
        }
        $this->assertTrue($found);
    }

    /**
     * Test get_user_message_preferences permissions
     */
    public function test_get_user_message_preferences_permissions() {
        $this->resetAfterTest(true);

        $user = self::getDataGenerator()->create_user();
        $otheruser = self::getDataGenerator()->create_user();
        $this->setUser($user);

        $this->expectException('moodle_exception');
        $prefs = core_message_external::get_user_message_preferences($otheruser->id);
    }
}