var snake, apple, squareSize, score, speed,
updateDelay, direction, new_direction,
addNew, cursors, scoreTextValue, speedTextValue,
textStyle_Key, textStyle_Value;

var Game = {

preload : function() {
// Here we load all the needed resources for the level.
// In our case, that's just two squares - one for the snake body and one for the apple.
game.load.image('snake', './assets/images/snake.png');
game.load.image('apple', './assets/images/apple.png');
},

create : function() {

// By setting up global variables in the create function, we initialise them on game start.
// We need them to be globally available so that the update function can alter them.

snake = []; // This will work as a stack, containing the parts of our snake
apple = {}; // An object for the apple;
squareSize = 15; // The length of a side of the squares. Our image is 15x15 pixels.
score = 0; // Game score.
speed = 0; // Game speed.
updateDelay = 0; // A variable for control over update rates.
direction = 'right'; // The direction of our snake.
new_direction = null; // A buffer to store the new direction into.
addNew = false; // A variable used when an apple has been eaten.

// Set up a Phaser controller for keyboard input.
cursors = game.input.keyboard.createCursorKeys();

game.stage.backgroundColor = '#061f27';

// Generate the initial snake stack. Our snake will be 10 elements long.
// Beginning at X=150 Y=150 and increasing the X on every iteration.
for(var i = 0; i < 10; i++){
snake[i] = game.add.sprite(150+i*squareSize, 150, 'snake'); // Parameters are (X coordinate, Y coordinate, image)
}


// Genereate the first apple.
this.generateApple();


// Add Text to top of game.
textStyle_Key = { font: "bold 14px sans-serif", fill: "#46c0f9", align: "center" };
textStyle_Value = { font: "bold 18px sans-serif", fill: "#fff", align: "center" };

// Score.
game.add.text(30, 20, "SCORE", textStyle_Key);
scoreTextValue = game.add.text(90, 18, score.toString(), textStyle_Value);
// Speed.
game.add.text(500, 20, "SPEED", textStyle_Key);
speedTextValue = game.add.text(558, 18, speed.toString(), textStyle_Value);

},



update: function() {
// The update function is called constantly at a high rate (somewhere around 60fps),
// updating the game field every time.
// We are going to leave that one empty for now.
},


generateApple: function(){

// Chose a random place on the grid.
// X is between 0 and 585 (39*15)
// Y is between 0 and 435 (29*15)

var randomX = Math.floor(Math.random() * 40 ) * squareSize,
randomY = Math.floor(Math.random() * 30 ) * squareSize;

// Add a new apple.
apple = game.add.sprite(randomX, randomY, 'apple');
}

};