//globale (überall in der Datei verfügbar) Variablen
var background_canvas;
var background_ctx;
var main_canvas;
var main_ctx;
var game_object;
var background_picture;
var earth_picture;

//var earth_x_pos = 350;
//var earth_y_pos = 600;

//var back_x_pos = -1;
//var back_y_pos = -1;

var earth;
var back;
var enemy1;
var enemy2;
var enemy3;
var enemy1_y;
var enemy1_x;


function init() {
	//Hole Referez auf das game_object (Viewport)
    game_object         = document.getElementById('game_object');

    //Event Listener für das Event 'mousemove' registrieren, bei Eintritt mouse aufrufen
	game_object.addEventListener("mousemove",mouse);

	//Spielobjekte bauen
    back = new Player(-1,-1,1600,1200,'assets/background.png');

	earth = new Player(350,600,100,100,'assets/planet.png');
	earth.setOpacity(0.4);
	console.log( earth.getOpacity() );


	var direction;
	if( Math.random() < 0.5) {			//Wert zwischen 0 und 1.0
		direction = 'left';
	}else {
		direction = 'right';
	}
	console.log( direction);


	if (Math.random() < 0.5) {
		enemy1_y = -50;
	} else {
		enemy1_y = 550;
	}

	if (Math.random() == 'right') {
		enemy1_x = 750;
	} else {
		enemy1_x = -50;
	}
	console.log( enemy1_y);

    enemy1 = new Player(enemy1_x,enemy1_y,100,100,'assets/beetleship.png');
   if (direction == 'right') {
	   enemy1.setTransformX(-1);
   }

	enemy2 = new Player(350,350,100,100,'assets/octopus.png');
	if (direction == 'right') {
	   enemy2.setTransformX(-1);
   }

    enemy3 = new Player(450,350,100,100,'assets/rocketship.png');
	if (direction == 'right') {
	   enemy3.setTransformX(-1);
   }

}

function update() {
    //Die Funktion update 60 mal pro Sekunde aufrufen
    window.requestAnimFrame(update);

    //Weltkugel/Hintergrund bewegen
    if( earth.getY() > 250) {
        earth.setY( earth.getY() - 2 );
        //back_y_pos = back_y_pos - 0.6;
        back.setY( back.getY() - 0.3 );
    } else {
		//Endposition der Erde ist 350/250
	 if(enemy1.getX() < 350) {
            enemy1.setX( enemy1.getX() +5.33 );
        }else if (enemy1.getX() > 350) {
            enemy1.setX( enemy1.getX() -5.33 );
        }else if (enemy1.getX() == 350) {
           console.log("Erde X erreicht!");
        }
		//Endposition der Erde ist 350/250
		 if(enemy1.getY() < 250) {
            enemy1.setY( enemy1.getY() +4 );
        }else if (enemy1.getY() > 250) {
            enemy1.setY( enemy1.getY() -4 );
        }else if (enemy1.getY() == 250) {
           console.log("Erde Y erreicht!");
        }

	}
    render();
}

function render() {

    //Image auf den Zeichenhintergrund zeichen
    //background_ctx.clearRect(0,0,800,600);
    //background_ctx.drawImage(background_picture,back_x_pos,back_y_pos);
    //back.draw(background_ctx);


    //Image auf Hauptzeichenfläche zeichnen (Weltkugel)
    //main_ctx.clearRect(0,0,800,600);
    //main_ctx.rotate(3.14);

    //main_ctx.drawImage(earth_picture,earth_x_pos,earth_y_pos);

    //earth.draw(main_ctx);

    //Gegner zeichnen
    //enemy1.draw(main_ctx);
    //enemy2.draw(main_ctx);
    //enemy3.draw(main_ctx);
}