var game = new Phaser.Game(800, 600, Phaser.CANVAS, 'phaser-example', { preload: preload, create: create, update: update, render: render });

var ufo;
var Keys = Phaser.Keyboard;
var speed = 4;
var style = 'default';

function preload() {

    game.load.image('ground', 'assets/tests/ground-2x.png');
    game.load.image('river', 'assets/tests/river-2x.png');
    game.load.image('sky', 'assets/tests/sky-2x.png');
    game.load.image('cloud0', 'assets/tests/cloud-big-2x.png');
    game.load.image('cloud1', 'assets/tests/cloud-narrow-2x.png');
    game.load.image('cloud2', 'assets/tests/cloud-small-2x.png');
    game.load.image('ufo','assets/sprites/ufo.png');
    game.load.image('baddie','assets/sprites/space-baddie.png');
    game.load.spritesheet('button', 'assets/buttons/follow-style-button.png', 224, 70);

}

function create() {

    //  Make the world larger than the actual canvas
    game.world.setBounds(0, 0, 1400, 1400);

    for (var i=0; i < 10; i++)
    {
        game.add.sprite(game.world.randomX, game.world.randomY, 'baddie');
    }

    //  Background images
    game.add.tileSprite(0, 0, 1400, 600, 'sky');
    game.add.sprite(0, 360, 'ground');
    game.add.sprite(0, 400, 'river');
    game.add.sprite(200, 120, 'cloud0');
    game.add.sprite(-60, 120, 'cloud1');
    game.add.sprite(900, 170, 'cloud2');

    // ufo sprite
    ufo = game.add.sprite(300, 240, 'ufo');

    //registration point
    ufo.anchor.setTo(0.5, 0.5);

    game.camera.follow(ufo);

    // follow style switch buttons
    btn0 = game.add.button(6, 40, 'button', lockonFollow,this, 0, 0, 0);
    btn1 = game.add.button(6, 120, 'button', platformerFollow,this, 1, 1, 1);
    btn2 = game.add.button(6, 200, 'button', topdownFollow,this, 2, 2, 2);
    btn3 = game.add.button(6, 280, 'button', topdownTightFollow,this, 3, 3, 3);

}

function lockonFollow() {
    game.camera.follow(ufo, Phaser.Camera.FOLLOW_LOCKON);
    style = 'STYLE_LOCKON';
}

function platformerFollow() {
    game.camera.follow(ufo, Phaser.Camera.FOLLOW_PLATFORMER);
    style = 'STYLE_PLATFORMER';
}

function topdownFollow() {
    game.camera.follow(ufo, Phaser.Camera.FOLLOW_TOPDOWN);
    style = 'STYLE_TOPDOWN';
}

function topdownTightFollow() {
    game.camera.follow(ufo, Phaser.Camera.FOLLOW_TOPDOWN_TIGHT);
    style = 'STYLE_TOPDOWN_TIGHT';
}

function update() {

    if (game.input.keyboard.isDown(Keys.LEFT))
    {
        ufo.x -= speed;
        ufo.angle = -15;
    }
    else if (game.input.keyboard.isDown(Keys.RIGHT))
    {
        ufo.x += speed;
        ufo.angle = 15;
    }
    else if (game.input.keyboard.isDown(Keys.UP))
    {
        ufo.y -= speed;
    }
    else if (game.input.keyboard.isDown(Keys.DOWN))
    {
        ufo.y += speed;
    }
    else
    {
        ufo.angle = 0;
    }

}

function render () {

    game.debug.renderText('Click buttons to switch follow styles', 32, 32);
    game.debug.renderText('Current style: ' + style, 32, 64);

}