week11.py

# Week 11: Timed Coin Collector (Timer + Random)
# Goal: Add time pressure with countdown timer and win/lose conditions
# This creates urgency and makes the game more exciting!

import turtle
import random
import time  # New module for tracking time

# Setup screen
screen = turtle.Screen()
screen.title("Timed Coin Collector")
screen.setup(width=700, height=500)

# Create hero turtle
hero = turtle.Turtle()
hero.shape("turtle")
hero.penup()
hero.speed(0)

# Create coin turtle
coin = turtle.Turtle()
coin.shape("circle")
coin.color("gold")
coin.penup()
coin.speed(0)

# Create display turtle (for score AND timer)
writer = turtle.Turtle()
writer.hideturtle()
writer.penup()
writer.goto(-330, 210)

# Game variables
score = 0
STEP = 20
GAME_SECONDS = 20  # Total time to play

# Record when game starts
start_time = time.time()  # time.time() returns current time in seconds

# ===== Helper Functions =====

def place_coin():
    """Move coin to random position"""
    coin.goto(random.randint(-320, 320), random.randint(-200, 200))

def draw_ui():
    """Update score and timer display"""
    # Calculate how much time has passed
    elapsed = time.time() - start_time
    
    # Calculate remaining time (don't go below 0)
    remaining = max(0, int(GAME_SECONDS - elapsed))
    
    # Update display
    writer.clear()
    writer.write(f"Score: {score}   Time: {remaining}", 
                 font=("Arial", 16, "normal"))

def game_over():
    """Display game over message"""
    writer.goto(-80, 0)  # Move to center
    writer.write("GAME OVER", font=("Arial", 24, "bold"))

def check_time():
    """Check if time has run out"""
    if time.time() - start_time >= GAME_SECONDS:
        return True  # Time's up!
    return False     # Still time left

def check_collect():
    """Check if hero collected coin"""
    global score
    
    # Check if game is over first
    if check_time():
        game_over()
        return  # Stop checking collection
    
    # Check if hero is close to coin
    if hero.distance(coin) < 25:
        score += 1
        place_coin()
    
    # Update display (both score and timer)
    draw_ui()

# ===== Movement Functions =====
# Helper function to reduce code duplication

def move(dx, dy):
    """
    Move hero by dx, dy and check collection
    
    Args:
        dx: Change in X coordinate
        dy: Change in Y coordinate
    """
    # Check if game is over
    if check_time():
        game_over()
        return  # Don't allow movement if time's up
    
    # Move hero
    hero.goto(hero.xcor() + dx, hero.ycor() + dy)
    
    # Check if collected coin
    check_collect()

# Define arrow key functions using move() helper
def up():    move(0, STEP)    # Move up: no X change, +Y change
def down():  move(0, -STEP)   # Move down: no X change, -Y change
def left():  move(-STEP, 0)   # Move left: -X change, no Y change
def right(): move(STEP, 0)    # Move right: +X change, no Y change

# ===== Initialize Game =====
place_coin()   # Put first coin on screen
draw_ui()      # Show initial score and timer

# ===== Connect Keyboard Events =====
screen.listen()
screen.onkey(up, "Up")
screen.onkey(down, "Down")
screen.onkey(left, "Left")
screen.onkey(right, "Right")

# Keep window open
screen.mainloop()

# ===== Key Concepts =====
# 1. time.time() gives current time in seconds
# 2. Subtract start_time to get elapsed time
# 3. Check time before allowing actions
# 4. max(0, value) prevents negative numbers
# 5. Helper functions reduce code duplication