module animatedsprite;

import dsfml.window.all;
import dsfml.system.all;
import dsfml.graphics.all;

class Frame {
    Image image;
    int length; // length in frames

    this(Image image, int length) {
	this.image = image;
	this.length = length;
    }	
}

class Animation {
    private Frame[] frames;
    private int current_frame_idx;
    private Frame current_frame;
    private int frame_counter;

    this() {
    
    }

    void add_frame(Image image, int length) {
	this.frames ~= new Frame(image, length);
    }

    void play() {
	this.current_frame = this.frames[0];
	this.current_frame_idx = 0;
    }

    Image get_image() {
	if(this.frame_counter >= this.current_frame.length) {
	    this.frame_counter = 0;
	    this.current_frame_idx++;
	    if (this.frames.length <= this.current_frame_idx) {
		// animation stop
		return null;
	    }
	    this.current_frame = this.frames[this.current_frame_idx];
	}
	this.frame_counter++;
	return this.current_frame.image;
    }
}

class AnimatedSprite : Sprite {
    private Animation current_animation = null;
    private bool is_loop = false;

    /* play an animation now. */
    void play_animation(Animation animation, bool loop=false) {
	this.current_animation = animation; 
	this.is_loop = loop;
	this.current_animation.play();
    }

    /* update everything. Perfect for an animated sprite */
    void update() {
	if(this.current_animation) {
	    Image img = this.current_animation.get_image();
	    if(img) {
		this.setImage(img);
	    }
	    else if (this.is_loop) {
		this.current_animation.play(); // is a loop, play again
	    } else {
		this.current_animation = null;
	    }
	}	    
    }	
}