var mongoose = require('mongoose'),
	Schema	 = mongoose.Schema,
	ObjectId = Schema.ObjectId,
	UserSchema = require('./User').UserSchema;


var FriendRequest = new Schema({
	from		: {type: ObjectId, index:true}, // Why does not UserSchema.ObjectId work here, instead of ObjectId?
	to			: {type: ObjectId, index:true},

	confirmed	: {type: Boolean, index: true},

	created		: {type: Date, default: Date.now},
});

FriendRequest.pre('save', function youCantBefriendYourself(next) {

	if (this.from == this.to) {
		next(new Error("A user can't befriend themselves."));
	} else {
		next();
	}
});


FriendRequest.pre('save', function lookForPendingRequest(next, done) {
	next();
	var query = {
		$or:  [
				{'from': this.from,'to' : this.to},
				{'from': this.to,'to' : this.from}
			]
	};
	mongoose.model('FriendRequest').find(query, function(err,res) {
		if (res.length > 0)
			done(new Error("Pending friendrequest exists already"));
		else
			done();
	});
});

// @untested
FriendRequest.pre('save', function seeIfAlreadyFriends(next, done) {
	next();
	var query = {
		"_id"		: this.from,
		"friends" 	: this.to
	};
	mongoose.model('User').find(query, function(err,res) {
		if (res.length > 0)
			done(new Error("The users are already friends"));
		else
			done();
	});
});

module.exports.FriendRequest = mongoose.model('FriendRequest', FriendRequest);
module.exports.FriendRequestSchema = FriendRequest;