Proyectos de Subversion Moodle

<?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/>.

/**

 * Getting the minimum grade to pass target.

 *

 * @package   core_course

 * @copyright 2019 Victor Deniz <victor@moodle.com>

 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

namespace core_course\analytics\target;

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

/**

 * Getting the minimum grade to pass target.

 *

 * @package   core_course

 * @copyright 2019 Victor Deniz <victor@moodle.com>

 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later

 */

class course_gradetopass extends course_enrolments {

    /**

     * Courses grades to pass.

     * @var mixed[]

     */

    protected $coursesgradetopass = array();

    /**

     * Courses grades.

     * @var mixed[]

     */

    protected $coursesgrades = array();

    /**

     * Returns the grade to pass a course.

     *

     * Save the value in $coursesgradetopass array to prevent new accesses to the database.

     *

     * @param int $courseid The course id.

     * @return array The courseitem id and the required grade to pass the course.

     */

    protected function get_course_gradetopass($courseid) {

        if (!isset($this->coursesgradetopass[$courseid])) {

            // Get course grade_item.

            $courseitem = \grade_item::fetch_course_item($courseid);

            $ci = array();

            $ci['courseitemid'] = $courseitem->id;

            if ($courseitem->gradetype == GRADE_TYPE_VALUE && grade_floats_different($courseitem->gradepass, 0.0)) {

                $ci['gradetopass'] = $courseitem->gradepass;

            } else {

                $ci['gradetopass'] = null;

            }

            $this->coursesgradetopass[$courseid] = $ci;

        }

        return $this->coursesgradetopass[$courseid];

    }

    /**

     * Returns the grade of a user in a course.

     *

     * Saves the grades of all course users in $coursesgrades array to prevent new accesses to the database.

     *

     * @param  int $courseitemid The course item id.

     * @param  int $userid the user whose grade is requested.

     * @return array The courseitem id and the required grade to pass the course.

     */

    protected function get_user_grade($courseitemid, $userid) {

        // If the user grade for this course is not available, get all the grades for the course.

        if (!isset($this->coursesgrades[$courseitemid])) {

            // Ony a course is cached to avoid high memory usage.

            unset($this->coursesgrades);

            $gg = new \grade_grade(null, false);

            $usersgrades = $gg->fetch_all(array('itemid' => $courseitemid));

            if ($usersgrades) {

                foreach ($usersgrades as $ug) {

                    $this->coursesgrades[$courseitemid][$ug->userid] = $ug->finalgrade;

                }

            }

        }

        if (!isset($this->coursesgrades[$courseitemid][$userid])) {

            $this->coursesgrades[$courseitemid][$userid] = null;

        }

        return $this->coursesgrades[$courseitemid][$userid];

    }

    /**

     * Returns the name.

     *

     * If there is a corresponding '_help' string this will be shown as well.

     *

     * @return \lang_string

     */

    public static function get_name(): \lang_string {

        return new \lang_string('target:coursegradetopass', 'course');

    }

    /**

     * Returns descriptions for each of the values the target calculation can return.

     *

     * @return string[]

     */

    protected static function classes_description() {

        return array(

            get_string('targetlabelstudentgradetopassno', 'course'),

            get_string('targetlabelstudentgradetopassyes', 'course')

        );

    }

    /**

     * Discards courses that are not yet ready to be used for training or prediction.

     *

     * Only courses with "value" grade type and grade to pass set are valid.

     *

     * @param \core_analytics\analysable $course

     * @param bool $fortraining

     * @return true|string

     */

    public function is_valid_analysable(\core_analytics\analysable $course, $fortraining = true) {

        $isvalid = parent::is_valid_analysable($course, $fortraining);

        if (is_string($isvalid)) {

            return $isvalid;

        }

        $courseitem = $this->get_course_gradetopass ($course->get_id());

        if (is_null($courseitem['gradetopass'])) {

            return get_string('gradetopassnotset', 'course');

        }

        return true;

    }

    /**

     * The user's grade in the course sets the target value.

     *

     * @param int $sampleid

     * @param \core_analytics\analysable $course

     * @param int $starttime

     * @param int $endtime

     * @return float|null 0 -> course grade to pass achieved, 1 -> course grade to pass not achieved

     */

    protected function calculate_sample($sampleid, \core_analytics\analysable $course, $starttime = false, $endtime = false) {

        if (!$this->enrolment_active_during_analysis_time($sampleid, $starttime, $endtime)) {

            // We should not use this sample as the analysis results could be misleading.

            return null;

        }

        $userenrol = $this->retrieve('user_enrolments', $sampleid);

        // Get course grade to pass.

        $courseitem = $this->get_course_gradetopass($course->get_id());

        // Get the user grade.

        $usergrade = $this->get_user_grade($courseitem['courseitemid'], $userenrol->userid);

        if ($usergrade >= $courseitem['gradetopass']) {

            return 0;

        }

        return 1;

    }

}