let mongoose = require('mongoose');
let Schema = mongoose.Schema;
let BookSchema = new Schema(
    {
        title: {type: String,required: true},
        author: {type: Schema.ObjectId,ref:'Author',required: true},
        summary: {type: String, required:true},
        isbn: {type: String, required:true},
        genre: [{type: Schema.ObjectId, ref:'Genre'}]
    }
);
BookSchema
    .pre('countDocuments');
BookSchema
.virtual('url')
.get(function () {
    return '/catalog/book/'+this._id;
});

module.exports = mongoose.model('Book',BookSchema);

var Book = require('../models/book');
var Author = require('../models/author');
var Genre = require('../models/genre');
var BookInstance = require('../models/bookinstance');
var async = require('async');

    exports.index = function(req, res) {
        async.parallel({
                book_count: function (callback) {
                    Book.countDocuments({},callback);
                }
            },
            function (err,results) {
                res.render('index',{title: 'Local Library Home',error:err, data:results});
                res.json({data: results});
            });
        res.send('NOT IMPLEMENTED: Site Home Page');
    };