// 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/>.

/**
 * @package    qtype_algebra
 * @copyright  2017 Jean-Michel Vedrine
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

angular.module('mm.addons.qtype_algebra')

/**
 * Short answer question handlers.
 *
 * @module mm.addons.qtype_algebra
 * @ngdoc service
 * @name $mmaQtypeAlgebraHandler
 */
.factory('$mmaQtypeAlgebraHandler', function($mmUtil) {

    var self = {};

    /**
     * Check if a response is complete.
     *
     * @param  {Object} question Question.
     * @param  {Object} answers  Question answers (without prefix).
     * @return {Mixed}           True if complete, false if not complete, -1 if cannot determine.
     */
    self.isCompleteResponse = function(question, answers) {
        return answers['answer'] || answers['answer'] === 0;
    };

    /**
     * Whether or not the module is enabled for the site.
     *
     * @return {Boolean}
     */
    self.isEnabled = function() {
        return true;
    };

    /**
     * Check if a student has provided enough of an answer for the question to be graded automatically,
     * or whether it must be considered aborted.
     *
     * @param  {Object} question Question.
     * @param  {Object} answers  Question answers (without prefix).
     * @return {Mixed}           True if gradable, false if not gradable, -1 if cannot determine.
     */
    self.isGradableResponse = function(question, answers) {
        return self.isCompleteResponse(question, answers);
    };

    /**
     * Check if two responses are the same.
     *
     * @param  {Object} question    Question.
     * @param  {Object} prevAnswers Previous answers.
     * @param  {Object} newAnswers  New answers.
     * @return {Boolean}            True if same, false otherwise.
     */
    self.isSameResponse = function(question, prevAnswers, newAnswers) {
        return $mmUtil.sameAtKeyMissingIsBlank(prevAnswers, newAnswers, 'answer');
    };

    /**
     * Get the directive.
     *
     * @param {Object} question The question.
     * @return {String}         Directive's name.
     */
    self.getDirectiveName = function(question) {
        return 'mma-qtype-algebra';
    };

    return self;
});