moodle_local_treestudyplan/classes/completionscanner.php

<?php
// This file is part of the Studyplan plugin for Moodle
//
// 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 <https://www.gnu.org/licenses/>.
/**
 * Scan course completion criteria for pending grading actions
 * @package    local_treestudyplan
 * @copyright  2023 P.M. Kuipers
 * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

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

require_once($CFG->libdir.'/externallib.php');

use \grade_item;
use \completion_criteria;

/**
 * Scan course completion criteria for pending grading actions
 */
class completionscanner {
    /**
     * Cache of supported mods
     * @var array 
     */
    private static $modsupported = [];
    /**
     * Cache of enrolled students in a particular course
     * @var array
     */
    private static $coursestudents = [];
    /** The internally used grading scanner
     * @var local\ungradedscanners\scanner_base
     */
    private $scanner = null;
    /** 
     * Course module
     * @var \cm_info
     */
    private $cm = null;
    /** @var grade_item */
    private $gi = null;
    /**
     * Cache of pending ungraded results per user
     * @var array
     */
    private $pendingcache = [];

    /**
     * Check if a certain activity type is supported for scanning pending results
     * @param string $mod name of activity module
     */
    public static function supported($mod) : bool {
        if (!array_key_exists($mod, self::$modsupported)) {
            self::$modsupported[$mod] = class_exists("\local_treestudyplan\\local\\ungradedscanners\\{$mod}_scanner");
        }
        return self::$modsupported[$mod];
    }

    /** 
     * List all users enrolled in a course as student by userid
     * @param int $courseid Course id of the course to check
     * @return int[] Array if user ids
     */
    public static function get_course_students($courseid) : array {
        global $CFG;
        if (!array_key_exists($courseid, self::$coursestudents)) {
            $students = [];
            $context = \context_course::instance($courseid);
            foreach (explode(', ', $CFG->gradebookroles) as $roleid) {
                $roleid = trim($roleid);
                $students = array_keys(get_role_users($roleid, $context, false, 'u.id', 'u.id ASC'));
            }
            self::$coursestudents[$courseid] = $students;
        }
        return self::$coursestudents[$courseid];
    }

    /**
     * Construct new scanner based on completion criteria and course
     * @param completion_criteria $crit Criteria to check for
     * @param stdClass $course Course DB record
     */
    public function __construct(completion_criteria $crit, $course) {
        $this->courseid = $course->id;
        $this->course = $course;
        $this->modinfo = get_fast_modinfo($course);
        $this->crit = $crit;

        $this->completioninfo = new \completion_info($course);

        // Find a related scanner if the type is an activity type.
        if ($crit->criteriatype == COMPLETION_CRITERIA_TYPE_ACTIVITY) {
            // First find the course module.
            $this->cm = $this->modinfo->get_cm($crit->moduleinstance);
            $gi = grade_item::fetch( ['itemtype' => 'mod',
                                      'itemmodule' => $this->cm->modname,
                                      'iteminstance' => $this->cm->instance,
                                      'courseid' => $this->courseid]);
            if ($gi !== false) {
                /* Grade none items should not be relevant.
                   Note that the grade status is probably only relevant if the item
                   has not yet received a completion, but has been submitted.
                */
                if (($gi->gradetype == GRADE_TYPE_VALUE || $gi->gradetype == GRADE_TYPE_SCALE)) {
                    // If it's a relevant grade type, initialize a scanner if possible.
                    $this->gi = $gi;
                    if (self::supported($gi->itemmodule)) {
                        $scannerclass = "\local_treestudyplan\\local\ungradedscanners\\{$gi->itemmodule}_scanner";
                        $this->scanner = new $scannerclass($gi);
                    }
                }
            }
        }

    }

    /**
     * Check if the criteria this scanner scans has pending submissions for a specific user
     * @param int $userid ID of the user to check for
     */
    public function pending($userid) : bool {
        if (!array_key_exists($userid, $this->pendingcache)) {
            if ($this->scanner === null) {
                $this->pendingcache[$userid] = false;
            } else {
                $this->pendingcache[$userid] = $this->scanner->has_ungraded_submission($userid);;
            }
        }
        return $this->pendingcache[$userid];
    }

    /**
     * Webservice structure for basic info
     * @param int $value Webservice requirement constant
     */
    public static function structure($value = VALUE_OPTIONAL) : \external_description {
        return new \external_single_structure([
            "ungraded" => new \external_value(PARAM_INT, 'number of ungraded submissions'),
            "completed" => new \external_value(PARAM_INT, 'number of completed students'),
            "completed_pass" => new \external_value(PARAM_INT, 'number of completed-pass students'),
            "completed_fail" => new \external_value(PARAM_INT, 'number of completed-fail students'),
            "students" => new \external_value(PARAM_INT, 'number of students that should submit'),
        ], "details about gradable submissions", $value);
    }

    /**
     * Webservice model for basic info
     */
    public function model() : array {

        // Get completion info.
        $students = self::get_course_students($this->courseid);
        $completed = 0;
        $ungraded = 0;
        $completedpass = 0;
        $completedfail = 0;
        foreach ($students as $userid) {
            if ($this->pending($userid)) {
                // First check if the completion needs grading.
                $ungraded++;
            } else {
                $completion = $this->completioninfo->get_user_completion($userid, $this->crit);

                if ($this->crit->criteriatype == COMPLETION_CRITERIA_TYPE_ACTIVITY) {
                    // If it's an activity completion, add all the relevant activities as sub-items.
                    $completionstatus = $this->completioninfo->get_grade_completion($this->cm, $userid);

                    if ($completionstatus == COMPLETION_COMPLETE_PASS) {
                        $completedpass++;
                    } else if ($completionstatus == COMPLETION_COMPLETE_FAIL) {
                        $completedfail++;
                    } else if ($completionstatus == COMPLETION_COMPLETE) {
                        $completed++;
                    }
                } else {
                    if ($completion->is_complete()) {
                        $completed++;
                    }
                }
            }
        }

        return [
            'ungraded' => $ungraded,
            'completed' => $completed,
            'completed_pass' => $completedpass,
            'completed_fail' => $completedfail,
            'students' => count($students),
        ];
    }

}