mongoose schemas

question

'use strict';

/**
 * Module dependencies.
 */
var mongoose = require('mongoose'),
	Schema = mongoose.Schema,
    _ = require('lodash'),
    async = require('async');

var AnswerSchema = new Schema({
    text: {
        type: String
    },
    right: {
        type: Boolean
    },
    assets: [{
        type: String
    }]
});

var Answer = mongoose.model('Answer', AnswerSchema);

/**
 * Question Schema
 */
var QuestionSchema = new Schema({
    created: {
        type: Date,
        default: Date.now
    },
    text: {
        type: String
    },
    answers: [AnswerSchema],
    theme: [{
        type: Schema.Types.ObjectId,
        ref:'Theme'
    }],
    assets: [{
        type: String
    }],
    tags: [{
        type: String,
        trim: true
    }]
});

mongoose.model('Question', QuestionSchema);

theme

'use strict';

/**
 * Module dependencies.
 */
var mongoose = require('mongoose'),
	Schema = mongoose.Schema;

/**
 * Theme Schema
 */
var ThemeSchema = new Schema({
    children: [ThemeSchema],
    name: {
        type: String,
        default: '',
        required: 'Please fill Theme name',
        trim: true
    },
    created: {
        type: Date,
        default: Date.now
    },
    description: {
        type: String,
        default: ''
    },
    iconUrl: {
        type: String
    },
    backgroundUrl: {
        type: String
    },
    cardUrl: {
        type: String
    },
    available: {
        type: Boolean
    }
});

ThemeSchema.statics.isValidForGame = function isValidForGame (themeId, callback) {
    mongoose.model('Theme').find({'_id': themeId, 'available': true}).exec(function(err, theme) {
        if (err) {
            callback(err, false);
            return;
        }

        if (theme.length === 0) {
            callback(null, false);
            return;
        }

        mongoose.model('Question').find({'theme': themeId}).exec(function(err, questions) {
            if (err) {
                callback(err, false);
                return;
            }

            if (questions.length === 0) {
                callback(null, false);
                return;
            }

            callback(null,theme[0]);

        });

    });
};

mongoose.model('Theme', ThemeSchema);