var sha1 = require("./sha1").hex;
var http = require("http");
var mysql = require('./mysql');
var settings = require("./settings");

if(Array.prototype.clear === undefined)
Array.prototype.clear = function()
{
    for(var i=this.length; i>=0; i--)
        delete this[i];
    this.length = 0;
    return this;
}

if(Array.prototype.contains === undefined)
Array.prototype.contains = function(element)
{
    return this.indexOf(element)!=-1;
}

if(Array.prototype.add === undefined)
Array.prototype.add = function(element)
{
    if(!this.contains(element))
        this.push(element);
}

if(Array.prototype.remove === undefined)
Array.prototype.remove = function(value)
{

    for(var i=0; i<this.length; i++)
        if(this[i] === value)
            this.splice(i--, 1);
    return this;
}

if(Array.prototype.clean === undefined)
Array.prototype.clean = function()
{
    for(var i=0; i<this.length; i++)
        if(this[i] === undefined
        || this[i] === null)
            this.splice(i--, 1);
    return this;
}

if(Array.prototype.clear === undefined)
Array.prototype.clear = function()
{
    for(var i=this.length; i>=0; i--)
        delete this[i];
    this.length = 0;
    return this;
}

function JSONResponse(database, request, response)
{
    var self = this;

    this._user = undefined;
    this._database = database;
    this._request = request;
    this._response = response;
    this._JSONObject = {};
    this._time = new Date();

    this._cookie = {};

    var rawcookie = request.headers.cookie
            ?request.headers.cookie.split(/;\s*/)
            :[];
    for(var i=0; i<rawcookie.length; i++)
    {
        rawcookie[i] = rawcookie[i].split("=");
        this._cookie[rawcookie[i][0]] = unescape(rawcookie[i][1]);
    }

    this._params = request.url.substr(1).split("/");

    console.log(this._params);

    response.writeHead(200,{"Content-Type": "application/json"});

    this.getTime = function()
    {
        return self._time;
    }

    this.getCookie = function(key)
    {
        return self._cookie[key];
    }

    /**
     * Get the currently logged in user. Calls the callback method with the user
     * that is logged in, or with NULL if there is no login.
     * @param cb The callback function.
     */
    this.validateLogin = function(cb)
    {
        if(this._user !== undefined)
        {
            cb(self._user);
            return;
        }
        if(!self.getCookie("login"))
        {
            self._user = null;
            cb(self._user);
            return;
        }
        var loginstr = self.getCookie("login").split(",");
        var userId = parseInt(loginstr[0]);
        var passHash = loginstr[1];
        self._database.getUser(userId, function(user)
        {
            user.checkPassword(passHash, function(isValid)
            {
                self._user = isValid?user:null;
                cb(self._user);
            });
        });
    }

    this.addError = function(message)
    {
        if(!(self._JSONObject.errors instanceof Array))
            self._JSONObject.errors = new Array();
        self._JSONObject.errors.push(message);
    }

    this.getParam = function(i)
    {
        return self._params[i];
    }

    this.getParams = function()
    {
        return self._params;
    }

    this.getUser = function()
    {
        return self._user;
    }

    this.set = function(key, value)
    {
        self._JSONObject[key] = value;
    }

    this.get = function(key)
    {
        return self._JSONObject[key];
    }

    this.end = function()
    {
        self._response.end(JSON.stringify(self._JSONObject, null, 2));
    }
}

function Database(sqlClient)
{
    var self = this;

    /** @var The MySQL Client connection. */
    this._sql = sqlClient;

    /** @var A cache with Product-objects. */
    this._products = {};

    /** @var A cache with User-objects. */
    this._users = {};

    /** @var A cache with Bid-objects. */
    this._bids = {};

    /** @var A reference to the last bid. */
    this._lastBid = undefined;

    this._init = function(cb)
    {
        self.query("SELECT id FROM bids ORDER BY id DESC LIMIT 1",
        [],
        function(results)
        {
            if(!results.length)
            {
                self._lastBid = null;
                self._init = undefined;
                if(cb)cb(self);
                return;
            }
            self.getBid(results[0].id, function(bid)
            {
                self._lastBid = bid;
                self.addOnBidPlacedEventListener(function(bid)
                {
                    self._lastBid = bid;
                });
                self._init = undefined;
                if(cb)cb(self);
                return;
            });
        });
    }

    /** @var An array with on-bid-placed-event listeners. */
    this._onBidPlacedEventListeners = [];

    /**
     *
     */
    this._triggerOnBidPlacedEventListeners = function(bid)
    {
        for(var i=0; i<self._onBidPlacedEventListeners.length; i++)
            self._onBidPlacedEventListeners[i](bid);
    }

    /**
     * Add a on-bid-placed-event-listener. The function will be called everytime
     * a bid is placed on any product. The callback will be given a
     * Bid-object which the bid was placed on as a first parameter.
     * @param cb The event-listener.
     */
    this.addOnBidPlacedEventListener = function(cb)
    {
        self._onBidPlacedEventListeners.add(cb);
    }

    this.removeOnBidPlacedEventListener = function(cb)
    {
        self._onBidPlacedEventListeners.remove(cb);
    }

    this.query = function(sql, params, cb)
    {
        self._sql.query(sql, params, function(err, results)
        {
            if(err)
            {
                console.log("ERROR EXECUTING QUERY:");
                console.log(sql);
                console.log(self._sql);
                throw err;
            }
            if(cb)cb(results);
        });
    }

    this.getLastBid = function()
    {
        return self._lastBid;
    }

    this.getProductsStartingBetween = function(start, end, cb)
    {
        self.query("SELECT id FROM products WHERE UNIX_TIMESTAMP(timeStart) "
            +"BETWEEN ? AND ?",
        [start.getTime()/1000, end.getTime()/1000],
        function(results)
        {
            var products = new Array();
            var productsLoadedCallback = function()
            {
                if(products.length < results.length)
                    return;
                if(cb)cb(products);
            }
            for(var i=0; i<results.length; i++)
            {
                self.getProduct(results[i].id, function(product)
                {
                    products.push(product);
                    productsLoadedCallback();
                });
            }
        });
    }

    this.getLastBidsPlacedAfterBid = function(bid, cb)
    {
        self.query("SELECT id FROM bids WHERE id > ? "
            +"GROUP BY product ORDER BY id",
        [bid?bid.getId():0],
        function(results)
        {
            var bids = new Array();
            var bidsLoadedCallback = function()
            {
                if(bids.length < results.length)
                    return;
                if(cb)cb(bids);
            }
            for(var i=0; i<results.length; i++)
            {
                self.getBid(results[i].id, function(bid)
                {
                    bids.push(bid);
                    bidsLoadedCallback();
                });
            }
        });
    }

    this.getLastBidsPlacedBetween = function(start, end, cb)
    {
        self.query("SELECT bid.id AS id FROM bids AS bid "
            +"JOIN products AS product ON bid.product = product.id "
            +"WHERE UNIX_TIMESTAMP(product.timeStart)+bid.centiTime/100 "
            +"BETWEEN ? AND ? GROUP BY product.id ORDER BY "
            +"bid.id DESC",
        [start.getTime()/1000, end.getTime()/1000],
        function(results)
        {
            var bids = new Array();
            var bidsLoadedCallback = function()
            {
                if(bids.length < results.length)
                    return;
                if(cb)cb(bids);
            }
            for(var i=0; i<results.length; i++)
            {
                self.getBid(results[i].id, function(bid)
                {
                    bids.push(bid);
                    bidsLoadedCallback();
                });
            }
        });
    }

    /**
     * Get a product from this database. Calls a callback method with the
     * retrieved Product-object on completion, or with NULL if the Product
     * doesn't exist.
     * @param id The id of the product to get.
     * @param cb The callback.
     */
    this.getProduct = function(id, cb)
    {
        id = parseInt(id);
        if(self._products[id] !== undefined)
        {
            if(cb)cb(self._products[id]);
            return;
        }
        self.query("SELECT title, UNIX_TIMESTAMP(timeStart) AS time, thumbnail,"
                +"value/100 AS value FROM products WHERE id = ? LIMIT 1",
        [id],
        function(results)
        {
            if(self._products[id])
            {
                console.log("Tried to reload Product #"+id+".");
                if(cb)cb(self._products[id]);
                return;
            }
            if(results.length == 0)
            {
                console.log("Loaded Product #"+id+": NULL");
                self._products[id] = null;
                if(cb)cb(self._products[id]);
                return;
            }
            self._products[id] = new Product(self, id,
                                             results[0].title,
                                             results[0].thumbnail,
                                             results[0].value,
                                             new Date(results[0].time*1000));
            self._products[id].addOnBidPlacedEventListener(
                    self._triggerOnBidPlacedEventListeners);
            self._products[id]._init(function(product)
            {
                console.log("Loaded Product #"+id+": "
                    +JSON.stringify(product.getTitle()));
                if(cb)cb(product);
            });
        });
    }

    /**
     * Get a user from this database. Calls a callback method with the retrieved
     * User-object on completion, or with NULL if there is no user with that id.
     * @param id The id of the user.
     * @param cb The callback.
     */
    this.getUser = function(id, cb)
    {
        id = parseInt(id);
        if(self._users[id] !== undefined)
        {
            if(cb)cb(self._users[id]);
            return;
        }
        self.query("SELECT username FROM users WHERE id = ? LIMIT 1",
        [id],
        function(results)
        {
            if(self._users[id])
            {
                console.log("Tried to reload User #"+id+".");
                if(cb)cb(self._users[id]);
                return;
            }
            self._users[id] = results.length == 0
                    ?null
                    :new User(self, id, results[0].username);
            console.log("Loaded User #"+id+": "
                +(self._users[id]
                    ?JSON.stringify(self._users[id].getUsername())
                    :"NULL"));
            if(cb)cb(self._users[id]);
        });
    }

    /**
     * Get a bid from this database. Calls a callback method with the retrieved
     * Bid-object on completion, or with NULL if there is no bid with that id.
     * @param id The id of the bid.
     * @param cb The callback.
     */
    this.getBid = function(id, cb)
    {
        id = parseInt(id);
        if(self._bids[id] !== undefined)
        {
            cb(self._bids[id]);
            return;
        }
        self.query("SELECT id, product, centiTime, user "
                +"FROM bids WHERE id = ? LIMIT 1",
        [id],
        function(results)
        {
            if(results.length == 0)
            {
                console.log("Loaded Bid #"+id+": NULL");
                self._bids[id] = null;
                if(cb)cb(self._bids[id]);
                return;
            }
            var bidUser = undefined;
            var bidProduct = undefined;
            var bidAdditionalDataCallback = function()
            {
                if(bidUser === undefined
                || bidProduct === undefined)
                    return;
                if(self._bids[id])
                {
                    console.log("Tried to reload Bid #"+id+".");
                    if(cb)cb(self._bids[id]);
                    return;
                }
                var time = new Date( bidProduct.getStartTime().getTime()
                                   + results[0].centiTime*10);
                self._bids[id] = new Bid(self, id, bidProduct,
                                         new Date(time), bidUser);
                console.log("Loaded Bid #"+id+": Bid #? on "
                    +JSON.stringify(bidProduct.getTitle()));
                if(cb)cb(self._bids[id]);
            }
            self.getUser(results[0].user, function(user)
            {
                bidUser = user;
                bidAdditionalDataCallback();
            });
            self.getProduct(results[0].product, function(product)
            {
                bidProduct = product;
                bidAdditionalDataCallback();
            });
        });
    }
}

function User(db, id, username)
{
    var self = this;

    this._database = db;
    this._id = id;
    this._username = username;

    this.getId = function()
    {
        return self._id;
    }

    this.getUsername = function()
    {
        return self._username;
    }

    /**
     * Check a user's password. Calls a callback after checking is done. The
     * callback will be called with a boolean as a first parameter, containing
     * TRUE if the given passwordhash did match the password or FALSE otherwise.
     */
    this.checkPassword = function(passhash, cb)
    {
        self._database.query("SELECT COUNT(1) FROM users "
                +"WHERE id = ? AND password = UNHEX(?) LIMIT 1",
        [self.getId(), passhash],
        function(results)
        {
            if(cb)cb(results.length > 0);
        });
    }

    this.toJSON = function()
    {
        return {
            id: self.getId(),
            username: self.getUsername()
        };
    }
}

function Product(db, id, title, thumbnail, value, time)
{
    var self = this;

    this._database = db;
    this._id = id;
    this._thumbnail = thumbnail;
    this._value = value;
    this._title = title;
    this._time = time;
    this._lastBid = undefined;

    this._init = function(cb)
    {
        self._database.query("SELECT id FROM bids WHERE product = ? "
            +"ORDER BY centiTime DESC LIMIT 1",
        [self.getId()],
        function(results)
        {
            if(results.length == 0)
            {
                self._lastBid = null;
                self._init = undefined;
                if(cb)cb(self);
                return;
            }
            db.getBid(results[0].id, function(bid)
            {
                self._lastBid = bid;
                self._init = undefined;
                if(cb)cb(self);
            });
        });
    }

    /** @var An array with on-bid-placed-event listeners. */
    this._onBidPlacedEventListeners = [];

    /**
     *
     */
    this._triggerOnBidPlacedEventListeners = function(bid)
    {
        for(var i=0; i<self._onBidPlacedEventListeners.length; i++)
            self._onBidPlacedEventListeners[i](bid);
    }

    /**
     * Add a on-bid-placed-event-listener. The function will be called everytime
     * a bid is placed on any product. The callback will be given a
     * Bid-object which the bid was placed on as a first parameter.
     * @param cb The event-listener.
     */
    this.addOnBidPlacedEventListener = function(cb)
    {
        self._onBidPlacedEventListeners.add(cb);
    }

    this.removeOnBidPlacedEventListener = function(cb)
    {
        self._onBidPlacedEventListeners.remove(cb);
    }

    /**
     * Get the id of this product.
     * @type Number
     * @return the id
     */
    this.getId = function()
    {
        return self._id;
    }

    this.getTitle = function()
    {
        return self._title;
    }

    this.getThumbnail = function()
    {
        return self._thumbnail;
    }

    this.getValue = function()
    {
        return self._value;
    }

    /**
     * Get the time this Product will start.
     * @type Date
     * @return The time
     */
    this.getStartTime = function()
    {
        return self._time;
    }

    this.getLastBid = function()
    {
        return self._lastBid;
    }

    this.placeBid = function(time, user, cb)
    {
        var centiTime = (time.getTime() - self.getStartTime().getTime())/10;
        self._database.query(
                "INSERT INTO bids (product, centiTime, user) VALUES(?,?,?)",
        [self.getId(), centiTime, user.getId()],
        function(results)
        {
            db.getBid(results.insertId, function(bid)
            {
                self._lastBid = bid;
                self._triggerOnBidPlacedEventListeners(bid);
                if(cb)cb(bid);
            });
        });
    }

    this.toJSON = function()
    {
        var bid = self.getLastBid();
        return {
            id: self.getId(),
            title: self.getTitle(),
            time: self.getStartTime().getTime(),
            thumbnail: self.getThumbnail(),
            value: self.getValue(),
            lastBid: !bid?null:{
                id: bid.getId(),
                time: bid.getTime().getTime(),
                user: {
                    id: bid.getUser().getId(),
                    username: bid.getUser().getUsername()
                }
            }
        };
    }
}

function Bid(db, id, product, time, user)
{
    var self = this;

    this._database = db;
    this._id = id;
    this._product = product;
    this._time = time;
    this._user = user;

    this.getId = function()
    {
        return self._id;
    }

    /**
     * Get the time this Bid was placed.
     * @type Date
     * @return The time
     */
    this.getTime = function()
    {
        return self._time;
    }

    this.getProduct = function()
    {
        return self._product;
    }

    this.getUser = function()
    {
        return self._user;
    }

    this.toJSON = function()
    {
        return {
            id: self.getId(),
            time: self.getTime().getTime(),
            user: self.getUser().toJSON(),
            product: self.getProduct().toJSON()
        };
    }
}

function handleJSONResponse(response)
{
    switch(response.getParam(0))
    {
        case "place-bid":
            var bidProduct = undefined;
            var bidUser = undefined;
            var productAndUserFetchedCallback = function()
            {
                if(bidProduct === undefined
                || bidUser === undefined)
                    return;
                if(!bidUser||!bidProduct)
                {
                    if(!bidUser)
                        response.addError("Placing a bid requires a login.");
                    if(!bidProduct)
                        response.addError("Product does not exist.");
                    response.end();
                    return;
                }
                bidProduct.placeBid(response.getTime(), bidUser,
                function(bid)
                {
                    response.set("bid", bid?bid.toJSON():null);
                    response.end();
                });
            }
            db.getProduct(response.getParam(1), function(product)
            {
                bidProduct = product;
                productAndUserFetchedCallback();
            });
            response.validateLogin(function(user)
            {
                bidUser = user;
                productAndUserFetchedCallback();
            });
            break;
        case "next-bid-since":
            db.getBid(parseInt(response.getParam(1)), function(sinceBid)
            {
                if(sinceBid != db.getLastBid())
                {
                    db.getLastBidsPlacedAfterBid(sinceBid,
                    function(bids)
                    {
                        var bidData = new Array(bids.length);
                        for(var i=0; i<bidData.length; i++)
                            bidData[i] = bids[i].toJSON();
                        response.set("bids", bidData);
                        response.end();
                    });
                }
                else
                {
                    db.addOnBidPlacedEventListener(function(bid)
                    {
                        response.set("bids", [bid]);
                        response.end();
                    });
                }
            });
            break;
        case "active-products":
            db.getProductsStartingBetween(new Date(0), new Date(), function(products)
            {
                var productData = new Array(products.length);
                for(var i=0; i<productData.length; i++)
                    productData[i] = products[i].toJSON();
                response.set("active-products", productData);
                response.end();
            });
            break;
        case "product-info":
            db.getProduct(response.getParam(1), function(product)
            {
                var bid = product.getLastBid();
                response.set("product", product?product.toJSON():null);
                response.end();
            });
            break;
        case "time":
            response.set("time", response.getTime().getTime());
            response.end();
            break;
        default:
            response.addError("Unknown Command");
            response.end();
    }
}

var client = mysql.Client();
client.host = settings.sqlHost;
client.user = settings.sqlUser;
client.password = settings.sqlPass;
client.database = settings.sqlDatabase;

client.connect();

var db = new Database(client);
db._init(function(db)
{
    http.createServer(function(request, response)
    {
        var jsonresponse = new JSONResponse(db, request, response);
        handleJSONResponse(jsonresponse);
    }).listen(settings.httpPort);
});