import javalib.funworld.*;
import javalib.worldimages.*;
import javalib.worldcanvas.*;
import javalib.colors.*;
import tester.*;

import java.awt.Color;
import java.util.*;


/* --- THE OCEAN WORLD -----------------------------------------------
 Fish swim across the screen from right to left. There may be one fish,
 or a whole school of fish, or none at a time. A hungry shark swims in
 place at the left side, moving only up and down, controlled by the
 \scheme{"up"} and \scheme{"down"} keys. It tries to catch and eat the
 fish. It gets bigger with each fish it eats, it keeps getting hungrier
 and hungrier as the time goes on between the catches. It dies of
 starvation, if not fed in time.
 --------------------------------------------------------------------*/



/*
 +--------+
 | CartPt |
 +--------+
 | int x  |
 | int y  |
 +--------+
 
 */
//to represent a location in the graphics window
class CartPt extends Posn{

	// a random number generator
	Random rand = new Random();
	
	CartPt(int x, int y){
		super(x, y);
	}
	
	/* Template:
	 Fields:
	 ... this.x ...              -- int
	 ... this.y ...              -- int   
	 Methods:
	 ... this.distTo(CartPt) ...  -- double
	 
	 */
	
	// compute the distance from this posn to the given one
	int distTo(CartPt that){
		return Math.abs(this.x - that.x) + Math.abs(this.y - that.y);
	}
	
	// move randomly left or right
	CartPt moveRand(){
		return new CartPt(this.x, this.y + rand.nextInt(5) - 2);
	}
}
// to represent one fish swimming in the ocean
class Fish{
	
	// the image of this fish
	WorldImage fishImage = new FromFileImage(new Posn(0, 0), 
			  "small-red-fish.png");
	
	// the location of this fish
	CartPt loc;
	
	// the constructor
	Fish(CartPt loc){
		this.loc = loc;
		fishImage = this.fishImage.getMovedTo(this.loc);
	}
	
	/* Template:
	 Fields:
	 ... this.loc ...            -- CartPt
	 ... this.fishImage ...      -- WorldImage   
	 Methods:
	 ... this.move() ...                                  -- Fish
	 ... this.isFood(Shark) ...                           -- boolean
	 Methods for fields:
	 ... this.loc.distTo(CartPt) ...                      -- double
	 ... this.fishImage.getMovedImage(int dx, int dy) ... -- WorldImage
	 ... this.fishImage.getMovedTo(CartPt) ...            -- WorldImage
	 ... this.fishImage.overlayImages(WorldImage) ...     -- WorldImage  
	 */
	
	// move this fish on tick
	Fish move(){
		if (this.loc.x < 0)
			return new Fish(new CartPt(400 - 3, this.loc.y));
		else
			return new Fish(new CartPt(this.loc.x - 3, this.loc.y));
	}
	
	// is this fish a shark food?
	boolean isFood(Shark shark){
		return this.loc.distTo(shark.loc) < 10;
	}
}

/*
 +------------+
 | Shark      |
 +------------+
 | CartPt loc |
 | int life   |
 +------------+
 */

// to represent a shark in an ocean world
class Shark {
	
	// the image of this fish
	WorldImage sharkImage = new FromFileImage(new Posn(0, 0), 
			"small-shark.png");
	
	// the location of this shark
	CartPt loc;
	
	// the number of lives left for this shark
	int life;
	
	// the constructor
	Shark(CartPt loc, int life) {
		this.loc = loc;
		this.life = life;
	}
	
	/* Template:
	 Fields:
	 ... this.loc ...             -- CartPt
	 ... this.sharkImage ...      -- WorldImage   
	 Methods:
	 ... this.???() ...                                  -- ???
	 
	 Methods for fields:
	 ... this.loc.distTo(CartPt) ...                      -- double
	 
	 ... this.sharkImage.getMovedImage(int dx, int dy) ... -- WorldImage
	 ... this.sharkImage.getMovedTo(CartPt) ...            -- WorldImage
	 ... this.sharkImage.overlayImages(WorldImage) ...     -- WorldImage  
	 */
}


/*
 +-------------+
 | OceanWorld  |
 +-------------+
 | Shark shark |
 | Fish fish   |
 +-------------+
 
 */

// to represent an ocean world
class OceanWorld extends World{
	Shark shark;
	Fish fish;

	// the width of the world
    int WIDTH = 400;
	
	// the height of the world
	int HEIGHT = 400;
	
	// the color of the ocean
	Color oceanColor = new Color(50, 150, 255);
	
	// the background image of the ocean
	WorldImage oceanImage = 
	new RectangleImage(new Posn(WIDTH/2, HEIGHT/2), WIDTH, HEIGHT, 
			   oceanColor);

	
	OceanWorld(Shark shark, Fish fish) {
		this.shark = shark;
		this.fish = fish;
	}
	
	/* Template:
	 Fields:
	 ... this.shark ...              -- Shark 
	 ... this.fish ...               -- Fish  
	 
	 Methods:
	 ... this.makeImage() ...                            -- WorldImage
	 ... this.onTick() ...                               -- Ocean
	 ... this.onKeyEvent(String) ...                     -- Ocean
	 ... this.caughtFish() ...                           -- boolean
	 
	 Methods for fields:
	 ... this.shark.???() ...                                  -- ???
	 
	 ... this.fish.move() ...                             -- double
	 ... this.fish.isFood(Shark) ...                      -- boolean
	 */
	
	// show just the great blue yonder
	public WorldImage makeImage(){
		return oceanImage.overlayImages(
		    this.fish.fishImage, 
		    this.shark.sharkImage);
	}
	
	// do nothing on tick
	public OceanWorld onTick(){
		return this;
	}
	
	// do nothing in response to the key events
	public OceanWorld onKeyEvent(String ke){
		return this;
	}
	
	// figure out whether the shark caught a fish in this world
	boolean caughtFish(){
		return this.fish.isFood(this.shark);
	}
}

// Examples of the classes Fish, Shark, OceanWorld and tests for all methods
class ExamplesOceanWorld{
	ExamplesOceanWorld(){}

	// the width of the world
    int WIDTH = 400;
	
	// the height of the world
	int HEIGHT = 400;
	
	Shark mac = new Shark(new CartPt(10, 100), 200);
	Shark mac2 = new Shark(new CartPt(10, 100), 100);
	Shark mac3 = new Shark(new CartPt(10, 100), -1);
	
	Fish fishy = new Fish(new CartPt(190, 100));
	
	Fish yummy = new Fish(new CartPt(15, 98));
	Fish gone = new Fish(new CartPt(15, 98));
	Fish gone2 = new Fish(new CartPt(WIDTH - 2, 98));
	
	Fish fishyClone = new Fish(new CartPt(190, 100));
	Fish yummyClone = new Fish(new CartPt(15, 98));
	Fish goneClone = new Fish(new CartPt(15, 98));
	Fish gone2Clone = new Fish(new CartPt(-2, 98));
	
	Fish fishy1 = new Fish(new CartPt(0, 0));
	Fish fishy2 = new Fish(new CartPt(0, 0));
	Fish fishy3 = new Fish(new CartPt(0, 0));
	Fish fishy4 = new Fish(new CartPt(0, 0));
	Fish fishy5 = new Fish(new CartPt(0, 0));
	
    
	OceanWorld sfw = new OceanWorld(this.mac, this.yummy); 
	
	// test that the expected value is one of several possible values
	public void testRandomMove(Tester t){
		t.checkRange((new CartPt(10, 20).moveRand()).y, 18, 23);
		t.checkOneOf(new CartPt(5, 20).moveRand(),
						 new CartPt(5, 18),
						 new CartPt(5, 19),
						 new CartPt(5, 20),
						 new CartPt(5, 21),
						 new CartPt(5, 22));
	}
	
	// test the move methods
	boolean testMove(Tester t){
		return
		t.checkExpect(this.fishy.move(), 
				      new Fish(new CartPt(187, 100))) &&
		sfw.bigBang(400, 400, 0.07);
	}
}