final version

from turtle import Turtle, Screen, mainloop
import turtle
import random
import math
import time
KEY_UP,KEY_DOWN,KEY_LEFT,KEY_RIGHT="Up","Down","Left","Right"
foods=[]
food_x=[]
food_y=[]
food_q=[]
foodNumber=0
g_direction=None
foodMove=0
caught=False
pausing=False
contacting=0
timeBegin=0
timeNow=0
moveTrace=[(0,0)]
moveTime=0
screen=Screen()
head=Turtle()
text=Turtle()
monster=Turtle()




def setWrite():
    screen.setup(width=500, height=500, startx=None, starty=None)
    turtle.title("Fenny's Game")
    text.up()
    text.setpos(-245,225)
    text.write("Welcom to Fenny's head game",move=False, align="left", font=("Arial", 10, "normal"))
    text.setpos(-245,205)
    text.write("You are going to use the four arrow keys to move the head around the the screen",\
        move=False, align="left", font=("Arial", 10, "normal"))
    text.setpos(-245,185)
    text.write("trying to consume all the food items before the monster catches you... ",\
    move=False, align="left", font=("Arial", 10, "normal"))
    text.setpos(-245,165)
    text.write("Click anywhere on the screen to start the game,have fun!",\
    move=False, align="left", font=("Arial", 10, "normal"))
    text.ht()#hide the turtle

def setSnake():
    head.up()
    head.setpos(0,0)
    head.shape("square")
    head.fillcolor("red")

def setMonster():
    monster.up()
    monster.shape("square")
    monster.fillcolor("purple")
    x1=random.randint(-200,-100)
    x2=random.randint(100,200)
    x=random.random()
    if x<1/2:
        x=x1
    else:
        x=x2
    y=random.randint(-200,-100)
    monster.setpos(x,y)

def setFood():
    global foods
    global food_q
    global food_x
    global food_y
    food1=Turtle()
    food2=Turtle()
    food3=Turtle()
    food4=Turtle()
    food5=Turtle()
    food6=Turtle()
    food7=Turtle()
    food8=Turtle()
    food9=Turtle()
    food10=Turtle()
    foods.append(food1)
    foods.append(food2)
    foods.append(food3)
    foods.append(food4)
    foods.append(food5)
    foods.append(food6)
    foods.append(food7)
    foods.append(food8)
    foods.append(food9)
    foods.append(food10)
    for i in range(10):
        foods[i].ht()
    food_x.append(0)
    food_y.append(0)
    food_q.append(5)
    for i in range(1,10):
        x=int(220*random.random())
        c=random.random()
        if c<1/2:
            x=(-1)*x
        y=int(220*random.random())
        d=random.random()
        if d<1/2:
            y=(-1)*y
        foods[i].up()
        foods[i].ht()
        foods[i].setpos(x,y)
        foods[i].write(i)
        food_x.append(x)
        food_y.append(y)
        food_q.append(i)


def moveUp():
    global g_direction
    if g_direction!=270:
        g_direction=90

def moveDown():
    global g_direction
    if g_direction!=90:
        g_direction=270

def moveLeft():
    global g_direction
    if g_direction!=0:
        g_direction=180

def moveRight():
    global g_direction
    if g_direction!=180:
        g_direction=0

def pause():
    global pausing
    pausing=not pausing

def screenControl():
    screen.onkey(moveUp,KEY_UP)
    screen.onkey(moveDown,KEY_DOWN)
    screen.onkey(moveLeft,KEY_LEFT)
    screen.onkey(moveRight,KEY_RIGHT)
    turtle.onkey(pause, "space")


def remove():
    global foodMove
    foods[foodMove].clear()
    food_x.remove(food_x[foodMove])
    food_y.remove(food_y[foodMove])
    food_q.remove(food_q[foodMove])#先remove 前面那个5==出现错误
    foods.remove(foods[foodMove])

def headMove(x,y):
    global g_direction
    if g_direction==90 and y>=230:#head的运动
        return 0
    if g_direction==180 and x<=-230:
        return 0
    if g_direction==270 and y<=-230:
        return 0
    if g_direction==0 and x>=230:
        return 0
    else:
        head.setheading(g_direction)
        head.forward(20)






def appear(x,y):
    head.color("blue","black")
    head.stamp()
    head.color("red")
    headMove(x,y)

def moveForward(x,y):
    if (g_direction!=90 or y<=230) and (g_direction!=180 or x>=-230) and \
    (g_direction!=270 or y>=-230) and (g_direction!=0 or x<=230):
        head.color("blue","black")
        head.stamp()
        head.color("red")
        headMove(x,y)
        head.clearstamp(head.stampItems[0])


def snakeMove():
    global caught
    global foodMove
    global food_x
    global food_y
    global food_q
    global foodNumber
    global pausing
    if g_direction!=None and pausing!=True:
        x,y=head.pos()
        i=0
        while i<len(foods):
            if abs(x-food_x[i])<20 and abs(y-food_y[i])<20:
                foodMove=i
                foodNumber=food_q[i]+foodNumber
                remove()
            i=i+1
        if foodNumber>0:
            appear(x,y)
            foodNumber-=1
        else:
            moveForward(x,y)
        if caught==True:
            return
        if len(head.stampItems)==50:
            text.up()
            text.ht()
            text.setpos(x,y)
            text.color("red")
            text.write("Winner!!!",font=("Arial", 20, "bold"))
            return
    elif pausing==True:
        head.forward(0)
    screen.ontimer(snakeMove,500)

def monsterMove():
    global g_direction
    global caught
    global pausing
    if g_direction!=None and pausing!=True:
        x,y=head.pos()
        a,b=monster.pos()
        delta1 = 2/math.sqrt(abs(x-a)*abs(x-a)+abs(y-b)*abs(y-b))
        delta2 = random.random() + 1
        if (abs(a-x)>20) or (abs(b-y)>20):
            monster.setx(a + (x - a)*delta1*delta2) # new pos
            monster.sety(b + (y- b)*delta1*delta2)
        else:
            caught=True
            x,y=head.pos()
            text.up()
            text.ht()
            text.setpos(x,y)
            text.color("yellow")
            text.write("Game Over!!!",font=("Arial", 20, "bold"))
            return
        if len(head.stampItems)==50:
            return
    elif pausing==True:
        monster.forward(0)
    screen.ontimer(monsterMove,100)

def contact():
    global g_direction
    global moveTrace
    global contacting
    global pausing
    if g_direction!=None and pausing!=True:
        length=len(head.stampItems)
        x,y=head.pos()
        a,b=monster.pos()
        if (x,y)!=moveTrace[-1]:
            moveTrace.append((x,y))
        for i in range(1,length+1):
            m,n=moveTrace[-i]
            if (abs(a-m)<20) and (abs(b-n)<20):
                contacting+=1
    screen.ontimer(contact,500)#speeed=snake



def timing():
    global g_direction
    global timeBegin
    global timeNow
    global moveTime
    if g_direction!=None:
        timeNow = time.time()
        moveTime=timeNow-timeBegin
    screen.ontimer(timing,500)