<?php
    require_once(dirname(dirname(dirname(__FILE__)))."/engine/engine.php");

    global $Dippler;

    $grade_max_length = Grade::getGradeMaxLength();
    $feedback_max_length = Grade::getFeedbackMaxLength();

    $learner_id = (int)get_input('learner_id');
    $course_id = (int)get_input('course_id');
    $grade = get_input('grade');
    $feedback = get_input('feedback');

	$data = array('messages' => '');
	$result = array('success' => 'false', 'data' => $data);

	if (!$learner_id || !$course_id || (empty($grade))) {
        $Dippler->add_system_message(_("At least one of the parameters is empty."), 'error');
        $data['messages'] = $Dippler->get_system_messages_html();
        $result['data'] = $data;
	    echo json_encode($result);
	    exit;
	}
    if ($Dippler->getStringLength($grade) > $grade_max_length || $Dippler->getStringLength($feedback) > $feedback_max_length) {
        $Dippler->add_system_message(sprintf(_("Grade length of %d or feedback length of %d characters is exceeded."), $grade_max_length, $feedback_max_length), 'error');
        $data['messages'] = $Dippler->get_system_messages_html();
        $result['data'] = $data;
	    echo json_encode($result);
	    exit;
    }

    $course = new Course($course_id);
    $course->load();

	if ($course && $course->getType() == 'course' && $course->canEdit()) {

        $new_grade = new Grade($learner_id);
        $new_grade->grade = $grade;
        $new_grade->feedback = $feedback;

        if ($new_grade->save()) {
            $result['success'] = 'true';
        } else {
            $Dippler->add_system_message(_("Grade could not be saved."), 'error');
        }
    } else {
        $Dippler->add_system_message(_("Not allowed to save grade."), 'error');
    }

    $data['messages'] = $Dippler->get_system_messages_html();
    $result['data'] = $data;
    echo json_encode($result);
	exit;
?>