function Interface() {

    var self = this;

    self.events = {};

    self.restartButton = document.querySelector('#restart-button');

    self.playerScoreContainer = document.querySelector('#player-score-container');
    self.playerScore = document.querySelector('#player-score');

    self.cpuScoreContainer = document.querySelector('#cpu-score-container');
    self.cpuScore = document.querySelector('#cpu-score');

    self.points = document.querySelector('#points');
    self.pointsButton = document.querySelector('#points-button');
    self.dicesButton = document.querySelector('#dices-button');
    self.diceContainer = document.querySelector('#dices');
    self.dices = self.diceContainer.children;

    self.message = document.querySelector('#message');

    self.dicesButton.disabled = true;
    self.pointsButton.disabled = true;

    self.restartButton.addEventListener("click", function() {
        self.fireEvent("restart");
    });

    self.pointsButton.addEventListener("click", function() {
        if (self.playing) {
            self.fireEvent("takePoints");
        }
    });


    self.dicesButton.addEventListener("click", function() {
        if (self.playing) {
            self.fireEvent("addPoints");
            self.fireEvent("roleDices");
        }
    });

    for (var diceIndex = 0; diceIndex < 6; diceIndex++) {
        var diceContainer = self.dices[diceIndex];
        diceContainer.diceIndex = diceIndex;
        diceContainer.addEventListener("click", function() {
            if (self.playing) {
                self.fireEvent("toggleDice", this.diceIndex);
            }
        });
    }

    this.setup();
};

Interface.prototype.setup = function() {
    this.dicesButton.disabled = true;
    this.pointsButton.disabled = true;
    this.message.classList.remove('visible');

};

Interface.prototype.on = function(event, callback) {
    if (!this.events[event]) {
        this.events[event] = [];
    }
    this.events[event].push(callback);
};

Interface.prototype.fireEvent = function(event, data) {
    var callbacks = this.events[event];
    if (callbacks) {
        callbacks.forEach(function(callback) {
            callback(data);
        });
    }
};

Interface.prototype.setDices = function(dices) {
    var self = this;

    for (var diceIndex = 0; diceIndex < 6; diceIndex++) {
        var dice = dices[diceIndex];
        var diceContainer = self.dices[diceIndex];
        diceContainer.innerHTML = dice.value + 1;

        if (dice.disabled) {
            diceContainer.disabled = true;
        } else {
            diceContainer.disabled = false;
        }

        if (dice.selected) {
            diceContainer.classList.add('selected');
        } else {
            diceContainer.classList.remove('selected');
        }

        if (dice.invalid) {
            diceContainer.classList.add('invalid');
            diceContainer.classList.remove('selected');
        } else {
            diceContainer.classList.remove('invalid');
        }
    }




};

Interface.prototype.animateDices = function(dices, callback) {
    var self = this;
    for (var diceIndex = 0; diceIndex < 6; diceIndex++) {
        var dice = dices[diceIndex];
        if (!dice.disabled && !dice.selected) {
            self.dices[diceIndex].classList.add("animate");
            self.dices[diceIndex].classList.add("duration" + diceIndex);
        }
    }

    setTimeout(function() {
        for (var diceIndex = 0; diceIndex < 6; diceIndex++) {
            self.dices[diceIndex].classList.remove("animate");
        }
        if (callback) {
            callback();
        }
    }, Math.random() * 500 + 500);
};

Interface.prototype.disableTakePoints = function(disabled) {
    this.pointsButton.disabled = disabled;
};

Interface.prototype.disabledRoleDices = function(disabled) {
    this.dicesButton.disabled = disabled;
};

Interface.prototype.setPoints = function(points) {
    this.points.innerHTML = points;
};

Interface.prototype.setPlaying = function(playing) {
    if (playing) {
        this.playing = true;
        this.playerScoreContainer.classList.add('active');
        this.cpuScoreContainer.classList.remove('active');
    } else {
        this.playing = false;
        this.playerScoreContainer.classList.remove('active');
        this.cpuScoreContainer.classList.add('active');
    }
};

Interface.prototype.setPlayer = function(player) {
    this.playerScore.innerHTML = player.score;
    this.playerScoreContainer.classList.remove('zilch-0');
    this.playerScoreContainer.classList.remove('zilch-1');
    this.playerScoreContainer.classList.remove('zilch-2');
    this.playerScoreContainer.classList.remove('zilch-3');
    this.playerScoreContainer.classList.add('zilch-' + player.zilch);

};

Interface.prototype.setCpu = function(cpu) {
    this.cpuScore.innerHTML = cpu.score;
    this.cpuScoreContainer.classList.remove('zilch-0');
    this.cpuScoreContainer.classList.remove('zilch-1');
    this.cpuScoreContainer.classList.remove('zilch-2');
    this.cpuScoreContainer.classList.remove('zilch-3');
    this.cpuScoreContainer.classList.add('zilch-' + cpu.zilch);
};

Interface.prototype.showMessage = function(message, fade) {
    var self = this;

    self.message.innerHTML = '<p>' + message + '</p>';

    self.message.classList.add('visible');

    if (fade) {
        setTimeout(function() {
            self.clearMessage();
        }, fade);
    }
};

Interface.prototype.clearMessage = function() {
    this.message.classList.remove('visible');
};