import random


def string_checker(question, valid_ans=("yes", "no")):
    error = f"Please enter a valid option from the following list: {valid_ans}"

    while True:
        user_response = input(question).strip().lower()

        if not user_response:
            print(error + "\n")
            continue

        for item in valid_ans:
            if user_response == item or user_response == item[0]:
                return item

        print(error + "\n")


def geometry_instruction():
    print("""
~~~ Geometry Quiz Instructions ~~~

~~ How to Play:
- Select the total number of rounds you want to play.
- Each turn will randomly ask for either the Area or Perimeter of a Shape (Square or Rectangle).
- Enter your numerical answer (no units required like cm² or m).
- Type <xxx> at any point to exit early.

~~ Number Ranges:
- Area dimensions: 2 to 24
- Perimeter dimensions: 2 to 36

Good luck!
""")


# --- Main Program ---

score = 0
answer_check = ["yes", "no"]

# Check for instructions
want_instruction = string_checker("Do you want to see the Geometry Quiz instructions? ", answer_check)
if want_instruction == "yes":
    geometry_instruction()

# Ask for total rounds
rounds_input = input("\nHow many rounds would you like to play? ").strip().lower()

while not rounds_input.isdigit() or int(rounds_input) < 1:
    print("⚠️ Please enter a valid number greater than 0. ⚠️")
    rounds_input = input("How many rounds would you like to play? ").strip().lower()

total_rounds = int(rounds_input)
question_num = 1

# Game Loop
while question_num <= total_rounds:
    print(f"\n~~~ Question {question_num} of {total_rounds} ~~~")

    # Pick shape: Square (1) or Rectangle (2)
    shape_type = random.choice(["square", "rectangle"])
    # Pick question type: Area (1) or Perimeter (2)
    calc_type = random.choice(["area", "perimeter"])

    if shape_type == "square":
        if calc_type == "area":
            side = random.randint(2, 24)
            correct_ans = side * side
            prompt_msg = f"What is the area of a square with a side length of {side}?"
        else:  # perimeter
            side = random.randint(2, 36)
            correct_ans = side * 4
            prompt_msg = f"What is the perimeter of a square with a side length of {side}?"
    else:  # rectangle
        if calc_type == "area":
            length = random.randint(2, 24)
            width = random.randint(2, 24)
            correct_ans = length * width
            prompt_msg = f"What is the area of a rectangle with length {length} and width {width}?"
        else:  # perimeter
            length = random.randint(2, 36)
            width = random.randint(2, 36)
            correct_ans = (length + width) * 2
            prompt_msg = f"What is the perimeter of a rectangle with length {length} and width {width}?"

    print(prompt_msg)
    user_input = input("Please enter your answer here or type 'xxx' to quit: ").strip().lower()

    # Exit code check
    if user_input == "xxx":
        print("\nThe game ended early.")
        break

    # Answer validation & scoring
    try:
        user_ans = int(user_input)
        if user_ans == correct_ans:
            print("Correct! Excellent job.")
            score += 1
        else:
            print(f"Incorrect. The correct answer was {correct_ans}")
    except ValueError:
        print(f"Invalid input (skipped). The correct answer was {correct_ans}")

    # Always increment round count after each question turn
    question_num += 1

# Final Results
rounds_played = question_num - 1

print("\n=========================")
print("Geometry Quiz Finished")
print(f"Your final score is {score}/{rounds_played}")
print("=========================")