import random

# generates the two terms to use in questions
def int_generator():
    # Generates a random number between 2 and 12
    term_1 = random.randint(2,12)
    term_2 = random.randint(2,12)
    return term_1, term_2

# generates a random operation for the quiz to use
def ops_generator():
    # The list of operators there is to choose from
    operators = ["+", "-", "*", "/"]

    # Randomizes the operator for the quiz
    op = random.choice(operators)
    return op

# generates the question using the specific operator that is chosen from the
# ops_gen function
def question_generator(term_1, term_2, op):
    if op == "+":
        question = f"{term_1} + {term_2}"
    elif op == "-":
        question = f"{term_1} - {term_2}"
    elif op == "*":
        question = f"{term_1} * {term_2}"
    else:
        question = f"{term_1} / {term_2}"
    return question

# Check that users have entered a valid
# option based on a list
def string_checker(question, valid_ans=("yes", "no")):
    error = f"Please enter a valid option from the following list: {valid_ans}"

    while True:

        # Get user response and make sure it's lowercase
        user_response = input(question).lower()

        for item in valid_ans:
            # check if the user response is a word in the list
            if item == user_response:
                return item

            # check if the user response is a word in the list
            # the first letter of an item in the list
            elif user_response == item[0]:
                return item

        # print error if user does not enter something that is valid
        print(error)
        print()

# Displays instructions
def instructions():
    print("""
*** Instructions ***

This is a basic arithmetic quiz. Each question will use two random numbers 
and a random operator (+, -, * or /).

Your goal is to answer each question correctly.

How it works:
• Choose how many questions you want to answer 
• For each round, a new maths question will appear.
• Type your answer and press <enter>.
• The quiz will tell you if you are correct or incorrect.
• If you entered an incorrect answer, the correct answer will be shown.
• Your total score will be shown at the end if you wish to see them.


Rules:
• All numbers are between 2 and 12.
• Division questions may produce decimal answers.
• If an answer contains decimals it will be rounded to 1 dp.
• You can exit the quiz at any time by typing 'xxx'.


Good luck!
""")

# checks for an integer between 5 and 15 for round count
def int_check():
    while True:
        error = "Please enter an integer from 5 - 15: "

        try:
            response = int(input("How many rounds (5 - 15) would you like to play?\nYour answer: "))

            # checks that the number is from the range of 5 - 15
            if 5 <= response <= 15:
                return response
            else:
                print(error)

        except ValueError:
            print(error)


# Main routine

# starts game variables
rounds_played = 0
correct_answers = 0
incorrect_answers = 0

# asks if user wants instructions
print("Welcome to the maths quiz!")
want_instructions = string_checker("Would you like to see the instructions on how to play?\nYour answer: ")
print()

# displays instructions if user requests them
if want_instructions == "yes":
    instructions()

# asks user how many rounds they want
# and prints the chosen amount of rounds
num_rounds = int_check()
print(f"The chosen amount of rounds is {num_rounds}")

# Game loop starts here

while rounds_played < num_rounds:

    # Game variables
    term_1, term_2 = int_generator()
    op = ops_generator()
    question = question_generator(term_1, term_2, op)
    answer = round(eval(question), 1)
    rounds = rounds_played + 1


    # Rounds heading
    print(f"\n___ Round {rounds} out of {num_rounds} ___")

    # Gets user input
    user_input = (input(f"What is {question}?:\nYour answer: ")).lower()

    # if user sends xxx ends the game
    if user_input == "xxx":
        break

    # turns user input into a float and checks if it is a number
    # if it isn't a number then add an incorrect answer and continue to
    # next round
    try:
        user_answer = round(float(user_input), 1)
    except ValueError:
        print("You entered an invalid answer. This will be marked incorrect.")
        incorrect_answers += 1
        rounds_played += 1
        continue

    # Checks if answer is correct
    if user_answer == answer:
        correct_answers += 1
        print("Correct!")
    else:
        incorrect_answers += 1
        print(f"Incorrect! The correct answer is {answer}.")

    # adds the current round played to the total
    rounds_played += 1

# End of game loop

print("You have finished the quiz!")
print()

# game score calculations
total = correct_answers + incorrect_answers
correct_percent = (correct_answers / total) * 100
incorrect_percent = (incorrect_answers / total) * 100

see_score = string_checker("Would you like to see your score?\nYour answer: ")

if see_score== "yes":
    print()
    print(f"You played {rounds_played} rounds!"
          f"\n With {correct_answers} ({correct_percent:.1f}%) correct answers"
          f"\n and {incorrect_answers} ({incorrect_percent:.1f}%) incorrect answers")