import turtle
import random
import time
wn = turtle.Screen()
setup = turtle.Turtle()
setup.hideturtle()
setup.speed(0)
wn.screensize(500,500)
Start = random.randrange(-250,250)
End = random.randrange(-250,250)
def start_setup():
    setup.penup()
    setup.goto(Start,-245)
    setup.pendown()
    setup.right(90)
    setup.write('Start')
    #setup.write('开始')
    for side in range(3):
        setup.forward(5)
        setup.left(90)
    setup.left(90)
    setup.forward(2.5)
    global Starting
    Starting = setup.position()
    setup.penup()
    setup.goto(End,-245)
    setup.pendown()
    setup.write('End')
    #setup.write('终点')
    for side in range(3):
        setup.forward(5)
        setup.left(90)
    global Ending
    Ending = setup.position()
start_setup()
destination = turtle.Turtle()
destination.penup()
destination.goto(-250,250)
booster = turtle.Turtle()
booster.penup()
booster.goto(Starting)
booster.pendown()
module = turtle.Turtle()
module.penup()
module.goto(Starting)
module.pencolor('red')
x = 0
while True:
    destination.forward(2)
    if destination.xcor() == 250 or destination.xcor() == -250:
        destination.left(180)
    if x == 0:
        direction = booster.towards(destination.position())
        booster.setheading(direction)
        booster.forward(3)
        module.setheading(direction)
        module.forward(3)
    if x != 0:
        booster.goto(destination.position())
        module.goto(destination.position())
        #module.goto(destination.position())
    if destination.xcor() - booster.xcor() > -1 and destination.xcor() - booster.xcor() < 1 and destination.ycor() - booster.ycor() > -1 and destination.ycor() - booster.ycor() < 1:
        if x == 20:
            module.goto(destination.position())
            break
        else:
            x += 1
            direction = module.towards(destination.position())
            module.setheading(direction)
            module.goto(destination.position())
print('Payload delivered.')
print('Module connected.')
#print('送货成功')
while True:
    destination.forward(2)
    if destination.xcor() == 250 or destination.xcor() == -250:
        destination.left(180)
    booster.forward(3)
    direction = booster.towards(Ending)
    booster.setheading(direction)
    if Ending[0] - booster.xcor() > -1 and Ending[0] - booster.xcor() < 1 and Ending[1] - booster.ycor() > -3 and Ending[1] - booster.ycor() < 3:
        break
    direction = module.towards(destination.position())
    module.setheading(direction)
    module.goto(destination.position())
print('We have made a safe touchdown on Earth.')
print('MISSION SUCCESS!!!!')
#print('降落成功')
#print('任务成功!!!')