import turtle
import random

class World:
    def __init__(self, maxX, maxY):
        self.maxX = maxX
        self.maxY = maxY
        self.thingList = []
        self.grid = []
        for y in range(maxY):
            row = []
            for x in range(maxX):
                row.append(None)
            self.grid.append(row)
        self.turtle = turtle.Turtle()
        self.screen = turtle.Screen()
        self.screen.setworldcoordinates(0, 0, maxX - 1, maxY - 1)
        self.turtle.hideturtle()

    def getMaxX(self):
        return self.maxX

    def getMaxY(self):
        return self.maxY

    def emptyLocation(self, x, y):
        if self.grid[y][x] == None:
            return True
        else:
            return False

    def lookAtLocation(self, x, y):
        return self.grid[y][x]

    def addThing(self, thing, x, y):
        thing.setX(x)
        thing.setY(y)
        self.grid[y][x] = thing
        thing.setWorld(self)
        self.thingList.append(thing)
        thing.appear()
    
    def deleteThing(self, thing):
        thing.hide()
        self.grid[thing.getY()][thing.getX()] = None
        self.thingList.remove(thing)

    def moveThing(self, oldX, oldY, newX, newY):
        self.grid[newY][newX] = self.grid[oldY][oldX]
        self.grid[oldY][oldX] = None

    def live(self):
        if len(self.thingList) > 0:
            index = random.randrange(0, len(self.thingList))
            self.thingList[index].live()

    def draw(self):
        self.screen.tracer(0)
        # draw bounding box
        self.turtle.forward(self.maxX - 1)
        self.turtle.left(90)
        self.turtle.forward(self.maxY - 1)
        self.turtle.left(90)
        self.turtle.forward(self.maxX - 1)
        self.turtle.left(90)
        self.turtle.forward(self.maxY - 1)
        self.turtle.left(90)
        # draw horizontal lines
        for y in range(self.maxY - 1):
            self.turtle.forward(self.maxX - 1)
            self.turtle.backward(self.maxX - 1)
            self.turtle.left(90)
            self.turtle.forward(1)
            self.turtle.right(90)
        self.turtle.forward(1)
        self.turtle.right(90)
        # draw vertical lines
        for x in range(self.maxX - 2):
            self.turtle.forward(self.maxY - 1)
            self.turtle.backward(self.maxY - 1)
            self.turtle.left(90)
            self.turtle.forward(1)
            self.turtle.right(90)
        self.screen.tracer(1)

class Creature:
    def __init__(self):
        self.turtle = turtle.Turtle()
        self.turtle.up()
        self.turtle.hideturtle()

        self.x = 0
        self.y = 0
        self.world = None                 
        
        self.breedTick = 0

    def setX(self,x):
        self.x = x
    
    def setY(self,y):
        self.y = y
    
    def getX(self):
        return self.x
    
    def getY(self):
        return self.y
    
    def setWorld(self,world):
        self.world = world
 
    def appear(self):
        self.turtle.goto(self.x, self.y)
        self.turtle.showturtle()

    def hide(self):
        self.turtle.hideturtle()
    
    def move(self,newX,newY):
        self.world.moveThing(self.x,self.y,newX,newY)
        self.x = newX
        self.y = newY
        self.turtle.goto(self.x, self.y)

    def live(self):
        print("ERROR: You must define live in the subclass")

    def tryToBreed(self, LifeForm):
        x = self.x
        y = self.y
        offsets = [(-1,1), (0,1), (1,1), (-1,0), (1,0), (-1,-1), (0,-1), (1,-1)]
        offset = random.choice(offsets)
        newX = offset[0] + x
        newY = offset[1] + y
        while newX < 0 or newX >= self.world.getMaxX() or newY < 0 or newY >= self.world.getMaxY():
            offset = random.choice(offsets)
            newX = offset[0] + x
            newY = offset[1] + y
        if self.world.emptyLocation(newX, newY):
            child = LifeForm()
            self.world.addThing(child, newX, newY)
            self.breedTick = 0

    def tryToMove(self):
        x = self.x
        y = self.y
        offsets = [(-1,1), (0,1), (1,1), (-1,0), (1,0), (-1,-1), (0,-1), (1,-1)]
        offset = random.choice(offsets)
        newX = offset[0] + x
        newY = offset[1] + y
        while newX < 0 or newX >= self.world.getMaxX() or newY < 0 or newY >= self.world.getMaxY():
            offset = random.choice(offsets)
            newX = offset[0] + x
            newY = offset[1] + y
        if self.world.emptyLocation(newX, newY):
            self.move(newX, newY)
           
    def tryToEat(self):
        print("ERROR: You must define tryToEat in the subclass")

class Fish(Creature):
    def __init__(self):
        super().__init__()
        self.turtle.shape('triangle')
        self.turtle.color('blue')  
        self.starveTick = 0


    def live(self):
        offsets = [(-1,1), (0,1), (1,1), (-1,0), (1,0), (-1,-1), (0,-1), (1,-1)]
        count = 0
        x = self.x
        y = self.y
        for offset in offsets:
            newX = offset[0] + x
            newY = offset[1] + y
            if newX >= 0 and newY >= 0 and newX < self.world.getMaxX() and newY < self.world.getMaxY():
                if not self.world.emptyLocation(newX, newY) and isinstance(self.world.lookAtLocation(newX, newY), Fish):
                    count += 1

        self.tryToEat()

        if count >= 2:
           self.world.deleteThing(self)
        else:
            self.breedTick += 1
            if self.breedTick >= 12:
                self.tryToBreed(Fish)
            self.tryToMove()

    def tryToEat(self):
        offsets = [(-1,1), (0,1), (1,1), (-1,0), (1,0), (-1,-1), (0,-1), (1,-1)]
        prey = []
        x = self.x
        y = self.y
        for offset in offsets:
            newX = offset[0] + x
            newY = offset[1] + y
            if newX >= 0 and newY >= 0 and newX < self.world.getMaxX() and newY < self.world.getMaxY():
                if not self.world.emptyLocation(newX, newY) and isinstance(self.world.lookAtLocation(newX, newY), Plant):
                    prey.append(self.world.lookAtLocation(newX, newY))
        if len(prey) > 0:
            plant = random.choice(prey)
            self.world.deleteThing(plant)
            self.move(plant.getX(), plant.getY())
            self.starveTick = 0
        else:
            self.starveTick += 1    
        
class Bear(Creature):
    def __init__(self):  
        super().__init__()
        self.turtle.shape('square')
        self.turtle.color('brown') 
        self.starveTick = 0

    def live(self):
        self.breedTick += 1
        if self.breedTick >= 8:
            self.tryToBreed(Bear)
        self.tryToEat()
        if self.starveTick >= 10:
            self.world.deleteThing(self)
        else:
            self.tryToMove()

    def tryToEat(self):
        offsets = [(-1,1), (0,1), (1,1), (-1,0), (1,0), (-1,-1), (0,-1), (1,-1)]
        prey = []
        x = self.x
        y = self.y
        for offset in offsets:
            newX = offset[0] + x
            newY = offset[1] + y
            if newX >= 0 and newY >= 0 and newX < self.world.getMaxX() and newY < self.world.getMaxY():
                if not self.world.emptyLocation(newX, newY) and isinstance(self.world.lookAtLocation(newX, newY), Fish):
                    prey.append(self.world.lookAtLocation(newX, newY))
        if len(prey) > 0:
            fish = random.choice(prey)
            self.world.deleteThing(fish)
            self.move(fish.getX(), fish.getY())
            self.starveTick = 0
        else:
            self.starveTick += 1
        
class Plant(Creature):
    def __init__(self):
        super().__init__()
        self.turtle.shape('circle')
        self.turtle.color('green')

    def live(self):
        self.breedTick = self.breedTick + 1
        if self.breedTick >= 5:
            self.tryToBreed(Plant)

bearCount = 1
fishCount = 25
plantCount = 20
worldLife = 2500
width = 8
height = 8
world = World(width, height)
world.draw()
for i in range(fishCount):
    fish = Fish()
    x = random.randrange(width)
    y = random.randrange(height)
    while not world.emptyLocation(x, y):
        x = random.randrange(width)
        y = random.randrange(height)
    world.addThing(fish, x, y)
for i in range(bearCount):
    bear = Bear()
    x = random.randrange(width)
    y = random.randrange(height)
    while not world.emptyLocation(x, y):
        x = random.randrange(width)
        y = random.randrange(height)
    world.addThing(bear, x, y)
for i in range(plantCount):
    plant = Plant()
    x = random.randrange(width)
    y = random.randrange(height)
    while not world.emptyLocation(x, y):
        x = random.randrange(width)
        y = random.randrange(height)
    world.addThing(plant, x, y)

for i in range(worldLife):
    world.live()