lib.php

<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle. If not, see <http://www.gnu.org/licenses/>.

/**
 * Library of interface functions and constants for module quizgame
 *
 * All the core Moodle functions, neeeded to allow the module to work
 * integrated in Moodle should be placed here.
 *
 * All the quizgame specific functions, needed to implement all the module
 * logic, should go to locallib.php. This will help to save some memory when
 * Moodle is performing actions across all modules.
 *
 * @package mod_quizgame
 * @copyright 2016 Lucas Tonussi <lptonussi@gmail.com>
 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
defined('MOODLE_INTERNAL') || die();

/**
 * Example constant, you probably want to remove this :-)
 */
define('QUIZGAME_ULTIMATE_ANSWER', 'JOHN_16:33');

/* Moodle core API */

/**
 * Returns the information on whether the module supports a feature
 *
 * See {@link plugin_supports()} for more info.
 *
 * @param string $feature
 *            FEATURE_xx constant for requested feature
 * @return mixed true if the feature is supported, null if unknown
 */
function quizgame_supports($feature)
{
    switch ($feature) {
        case FEATURE_MOD_INTRO:
            return true;
        case FEATURE_SHOW_DESCRIPTION:
            return true;
        case FEATURE_GRADE_HAS_GRADE:
            return true;
        case FEATURE_BACKUP_MOODLE2:
            return true;
        default:
            return null;
    }
}


/**
 * Saves a new instance of the quizgame into the database
 *
 * Given an object containing all the necessary data,
 * (defined by the form in mod_form.php) this function
 * will create a new instance and return the id number
 * of the new instance.
 *
 * @param stdClass $quizgame
 *            Submitted data from the form in mod_form.php
 * @param mod_quizgame_mod_form $mform
 *            The form instance itself (if needed)
 * @return int The id of the newly inserted quizgame record
 */
function quizgame_add_instance(stdClass $quizgame, mod_quizgame_mod_form $mform = null)
{
    global $DB;

    $quizgame->timecreated = time();

    // You may have to add extra stuff in here.

    $quizgame->id = $DB->insert_record('quizgame', $quizgame);

    quizgame_grade_item_update($quizgame);

    return $quizgame->id;
}

/**
 * Updates an instance of the quizgame in the database
 *
 * Given an object containing all the necessary data,
 * (defined by the form in mod_form.php) this function
 * will update an existing instance with new data.
 *
 * @param stdClass $quizgame
 *            An object from the form in mod_form.php
 * @param mod_quizgame_mod_form $mform
 *            The form instance itself (if needed)
 * @return boolean Success/Fail
 */
function quizgame_update_instance(stdClass $quizgame, mod_quizgame_mod_form $mform = null)
{
    global $DB;

    $quizgame->timemodified = time();
    $quizgame->id = $quizgame->instance;

    // You may have to add extra stuff in here.

    $result = $DB->update_record('quizgame', $quizgame);

    quizgame_grade_item_update($quizgame);

    return $result;
}

/**
 * Removes an instance of the quizgame from the database
 *
 * Given an ID of an instance of this module,
 * this function will permanently delete the instance
 * and any data that depends on it.
 *
 * @param int $id
 *            Id of the module instance
 * @return boolean Success/Failure
 */
function quizgame_delete_instance($id)
{
    global $DB;

    if (! $quizgame = $DB->get_record('quizgame', array(
        'id' => $id
    ))) {
        return false;
    }

    // Delete any dependent records here.

    $DB->delete_records('quizgame', array(
        'id' => $quizgame->id
    ));

    quizgame_grade_item_delete($quizgame);

    return true;
}

/**
 * Returns a small object with summary information about what a
 * user has done with a given particular instance of this module
 * Used for user activity reports.
 *
 * $return->time = the time they did it
 * $return->info = a short text description
 *
 * @param stdClass $course
 *            The course record
 * @param stdClass $user
 *            The user record
 * @param cm_info|stdClass $mod
 *            The course module info object or record
 * @param stdClass $quizgame
 *            The quizgame instance record
 * @return stdClass|null
 */
function quizgame_user_outline($course, $user, $mod, $quizgame)
{
    $return = new stdClass();
    $return->time = 0;
    $return->info = '';
    return $return;
}

/**
 * Prints a detailed representation of what a user has done with
 * a given particular instance of this module, for user activity reports.
 *
 * It is supposed to echo directly without returning a value.
 *
 * @param stdClass $course
 *            the current course record
 * @param stdClass $user
 *            the record of the user we are generating report for
 * @param cm_info $mod
 *            course module info
 * @param stdClass $quizgame
 *            the module instance record
 */
function quizgame_user_complete($course, $user, $mod, $quizgame)
{}

/**
 * Given a course and a time, this module should find recent activity
 * that has occurred in quizgame activities and print it out.
 *
 * @param stdClass $course
 *            The course record
 * @param bool $viewfullnames
 *            Should we display full names
 * @param int $timestart
 *            Print activity since this timestamp
 * @return boolean True if anything was printed, otherwise false
 */
function quizgame_print_recent_activity($course, $viewfullnames, $timestart)
{
    return false;
}

/**
 * Prepares the recent activity data
 *
 * This callback function is supposed to populate the passed array with
 * custom activity records. These records are then rendered into HTML via
 * {@link quizgame_print_recent_mod_activity()}.
 *
 * Returns void, it adds items into $activities and increases $index.
 *
 * @param array $activities
 *            sequentially indexed array of objects with added 'cmid' property
 * @param int $index
 *            the index in the $activities to use for the next record
 * @param int $timestart
 *            append activity since this time
 * @param int $courseid
 *            the id of the course we produce the report for
 * @param int $cmid
 *            course module id
 * @param int $userid
 *            check for a particular user's activity only, defaults to 0 (all users)
 * @param int $groupid
 *            check for a particular group's activity only, defaults to 0 (all groups)
 */
function quizgame_get_recent_mod_activity(&$activities, &$index, $timestart, $courseid, $cmid, $userid = 0, $groupid = 0)
{}

/**
 * Prints single activity item prepared by {@link quizgame_get_recent_mod_activity()}
 *
 * @param stdClass $activity
 *            activity record with added 'cmid' property
 * @param int $courseid
 *            the id of the course we produce the report for
 * @param bool $detail
 *            print detailed report
 * @param array $modnames
 *            as returned by {@link get_module_types_names()}
 * @param bool $viewfullnames
 *            display users' full names
 */
function quizgame_print_recent_mod_activity($activity, $courseid, $detail, $modnames, $viewfullnames)
{}

/**
 * Function to be run periodically according to the moodle cron
 *
 * This function searches for things that need to be done, such
 * as sending out mail, toggling flags etc ...
 *
 * Note that this has been deprecated in favour of scheduled task API.
 *
 * @return boolean
 */
function quizgame_cron()
{
    return true;
}

/**
 * Returns all other caps used in the module
 *
 * For example, this could be array('moodle/site:accessallgroups') if the
 * module uses that capability.
 *
 * @return array
 */
function quizgame_get_extra_capabilities()
{
    return array();
}

/* Gradebook API */

/**
 * Is a given scale used by the instance of quizgame?
 *
 * This function returns if a scale is being used by one quizgame
 * if it has support for grading and scales.
 *
 * @param int $quizgameid
 *            ID of an instance of this module
 * @param int $scaleid
 *            ID of the scale
 * @return bool true if the scale is used by the given quizgame instance
 */
function quizgame_scale_used($quizgameid, $scaleid)
{
    global $DB;

    if ($scaleid and $DB->record_exists('quizgame', array(
        'id' => $quizgameid,
        'grade' => - $scaleid
    ))) {
        return true;
    } else {
        return false;
    }
}

/**
 * Checks if scale is being used by any instance of quizgame.
 *
 * This is used to find out if scale used anywhere.
 *
 * @param int $scaleid
 *            ID of the scale
 * @return boolean true if the scale is used by any quizgame instance
 */
function quizgame_scale_used_anywhere($scaleid)
{
    global $DB;

    if ($scaleid and $DB->record_exists('quizgame', array(
        'grade' => - $scaleid
    ))) {
        return true;
    } else {
        return false;
    }
}

/**
 * Creates or updates grade item for the given quizgame instance
 *
 * Needed by {@link grade_update_mod_grades()}.
 *
 * @param stdClass $quizgame
 *            instance object with extra cmidnumber and modname property
 * @param bool $reset
 *            reset grades in the gradebook
 * @return void
 */
function quizgame_grade_item_update(stdClass $quizgame, $reset = false)
{
    global $CFG;
    require_once ($CFG->libdir . '/gradelib.php');

    $item = array();
    $item['itemname'] = clean_param($quizgame->name, PARAM_NOTAGS);
    $item['gradetype'] = GRADE_TYPE_VALUE;

    if ($quizgame->grade > 0) {
        $item['gradetype'] = GRADE_TYPE_VALUE;
        $item['grademax'] = $quizgame->grade;
        $item['grademin'] = 0;
    } else
        if ($quizgame->grade < 0) {
            $item['gradetype'] = GRADE_TYPE_SCALE;
            $item['scaleid'] = - $quizgame->grade;
        } else {
            $item['gradetype'] = GRADE_TYPE_NONE;
        }

    if ($reset) {
        $item['reset'] = true;
    }

    grade_update('mod/quizgame', $quizgame->course, 'mod', 'quizgame', $quizgame->id, 0, null, $item);
}

/**
 * Delete grade item for given quizgame instance
 *
 * @param stdClass $quizgame
 *            instance object
 * @return grade_item
 */
function quizgame_grade_item_delete($quizgame)
{
    global $CFG;
    require_once ($CFG->libdir . '/gradelib.php');

    return grade_update('mod/quizgame', $quizgame->course, 'mod', 'quizgame', $quizgame->id, 0, null, array(
        'deleted' => 1
    ));
}

/**
 * Update quizgame grades in the gradebook
 *
 * Needed by {@link grade_update_mod_grades()}.
 *
 * @param stdClass $quizgame
 *            instance object with extra cmidnumber and modname property
 * @param int $userid
 *            update grade of specific user only, 0 means all participants
 */
function quizgame_update_grades(stdClass $quizgame, $userid = 0)
{
    global $CFG, $DB;
    require_once ($CFG->libdir . '/gradelib.php');

    // Populate array of grade objects indexed by userid.
    $grades = array();

    grade_update('mod/quizgame', $quizgame->course, 'mod', 'quizgame', $quizgame->id, 0, $grades);
}

/* File API */

/**
 * Returns the lists of all browsable file areas within the given module context
 *
 * The file area 'intro' for the activity introduction field is added automatically
 * by {@link file_browser::get_file_info_context_module()}
 *
 * @param stdClass $course
 * @param stdClass $cm
 * @param stdClass $context
 * @return array of [(string)filearea] => (string)description
 */
function quizgame_get_file_areas($course, $cm, $context)
{
    return array();
}

/**
 * File browsing support for quizgame file areas
 *
 * @package mod_quizgame
 * @category files
 *
 * @param file_browser $browser
 * @param array $areas
 * @param stdClass $course
 * @param stdClass $cm
 * @param stdClass $context
 * @param string $filearea
 * @param int $itemid
 * @param string $filepath
 * @param string $filename
 * @return file_info instance or null if not found
 */
function quizgame_get_file_info($browser, $areas, $course, $cm, $context, $filearea, $itemid, $filepath, $filename)
{
    return null;
}

/**
 * Serves the files from the quizgame file areas
 *
 * @package mod_quizgame
 * @category files
 *
 * @param stdClass $course
 *            the course object
 * @param stdClass $cm
 *            the course module object
 * @param stdClass $context
 *            the quizgame's context
 * @param string $filearea
 *            the name of the file area
 * @param array $args
 *            extra arguments (itemid, path)
 * @param bool $forcedownload
 *            whether or not force download
 * @param array $options
 *            additional options affecting the file serving
 */
function quizgame_pluginfile($course, $cm, $context, $filearea, array $args, $forcedownload, array $options = array())
{
    global $DB, $CFG;

    if ($context->contextlevel != CONTEXT_MODULE) {
        send_file_not_found();
    }

    require_login($course, true, $cm);

    send_file_not_found();
}

/* Navigation API */

/**
 * Extends the global navigation tree by adding quizgame nodes if there is a relevant content
 *
 * This can be called by an AJAX request so do not rely on $PAGE as it might not be set up properly.
 *
 * @param navigation_node $navref
 *            An object representing the navigation tree node of the quizgame module instance
 * @param stdClass $course
 *            current course record
 * @param stdClass $module
 *            current quizgame instance record
 * @param cm_info $cm
 *            course module information
 */
function quizgame_extend_navigation(navigation_node $navref, stdClass $course, stdClass $module, cm_info $cm)
{
    // TODO Delete this function and its docblock, or implement it.
}

/**
 * Extends the settings navigation with the quizgame settings
 *
 * This function is called when the context for the page is a quizgame module. This is not called by AJAX
 * so it is safe to rely on the $PAGE.
 *
 * @param settings_navigation $settingsnav
 *            complete settings navigation tree
 * @param navigation_node $quizgamenode
 *            quizgame administration node
 */
function quizgame_extend_settings_navigation(settings_navigation $settingsnav, navigation_node $quizgamenode = null)
{
    // TODO Delete this function and its docblock, or implement it.
}


/**
 * Get the best current grade for a particular user in a quiz.
 *
 * @param object $quiz the quiz settings.
 * @param int $userid the id of the user.
 * @return float the user's current grade for this quiz, or null if this user does
 * not have a grade on this quiz.
 */
function quizgame_get_best_grade($quizgame, $userid) {
    global $DB;
    $grade = $DB->get_field('quizgame_grades', 'grade', array('quizgame' => $quizgame->id, 'userid' => $userid));
    // Need to detect errors/no result, without catching 0 grades.
    if ($grade === false) {
        return null;
    }
    return $grade + 0; // Convert to number.
}