// An image controlled by the arrow keys

class Util {
    static Map<string, PJImage> images = new Map<string, PJImage>();
    static PJImage getImage(string path) {
        if (!Util.images.contains(path)) {
            Util.images[path] = PJImage.loadFromFile(path);
        }
        return Util.images[path];
    }
}


class Program {
    int renderCounter = 0;
    SceneBase activeScene;
    PJGame gameInstance;

    void init() {
        this.gameInstance = new PJGame(this.postInit, this.update, this.render, 640, 480, 60);
        this.gameInstance.start();
    }

    void postInit() {
        this.activeScene = new SceneBase();
    }

    void update(List<PJEvent> events, Map<string, bool> pressedKeys) {
        this.activeScene.update(events, pressedKeys);
    }

    void render(PJImage screen) {
        this.activeScene.render(screen, this.renderCounter);
        this.renderCounter = this.renderCounter + 1;
    }
}

class SceneBase {

    SceneBase next;
    PJImage img;
    int x;
    int y;

    SceneBase() {
        this.next = this;
        this.img = Util.getImage('images/test.png');
        this.x = 100;
        this.y = 100;
    }

    void update(List<PJEvent> events, Map<string, bool> pressedKeys) {
        int v = 3;
        if (pressedKeys['left']) this.x = this.x - v;
        if (pressedKeys['right']) this.x = this.x + v;
        if (pressedKeys['up']) this.y = this.y - v;
        if (pressedKeys['down']) this.y = this.y + v;
    }

    void render(PJImage screen, int renderCounter) {
        screen.blit(this.img, this.x, this.y);
    }
}