import random

# 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 following list: {valid_ans}"

    while True:

        user_response = input(question).lower()

        for item in valid_ans:
            if item == user_response:
                return item

            elif user_response == item[0]:
                return item
        # print error if user does not enter something that valid
        print(error)
        print()


def instruction():
    print('''

**** Instructions ****

To begin, choose the number of rounds (or infinite mode).

Then, play against the computer.  You need 
P (paper) or S (scissors).

The rules are as follows:
o  Paper beats rock
o  Rock beats scissors
o  Scissors beats paper 



Good Luck!
''')



# checks for an integer more than 0 (allows <enter>)

def int_check(question):
    while True:
        error = "Please enter an integer that is 1 or more."

        to_check = input(question)

        #check for infinity mode
        if to_check == "":
            return "infinite"


        try:
            response = int(to_check)

            # checks that the number is more than / equal to 13
            if response < 1:
                print(error)
            else:
                return response

        except ValueError:
            print(error)




# win loose or tie result
def rps_compare(user, comp):

    # If the user and the computer choice is the same, it's a tie
    if user == comp:
        result = "tie"

    # There are three ways to win
    elif user == "paper" and comp == "rock":
        result = "win"
    elif user == "scissors" and comp == "paper":
        result = "win"
    elif user == "rock" and comp == "scissors":
        result = "win"

    # if it's not a win / tie, then it's a loss
    else:
        result = "lose"

    return result


# Main Routine Starts here

# Initialise game variables
mode = "regular"
rounds_played = 0


rps_list = ["rock", "paper", "scissors", "xxx"]


print("💎📄✂️ Rock / Paper / Scissors Game 💎📄✂️")
print()


# ask user if they want to see the instructions and display them if requested
want_instructions = string_checker("Do you want to read the instructions? ")

# checks users enter yes (y) or no (n)
if want_instructions == "yes":
    instruction()

# Ask user for number of rounds / infinite mode
num_rounds = int_check("How many rounds would you like? Push <enter> for infinite mode:")

if num_rounds == "infinite":
    mode = "infinite"
    num_rounds = 5

# Game loop starts here
while rounds_played < num_rounds:

    # Rounds headings (based on mode)
    if mode == "infinite":
        rounds_heading = f"\n♾♾♾ Round {rounds_played + 1} (Infinite Mode) ♾♾♾"
    else:
        rounds_heading = f"\n💿💿💿 Round {rounds_played + 1} of {num_rounds} 💿💿💿"

    print(rounds_heading)

    # randomly choose from, rps list (excluding the exit code)
    comp_choice = random.choice(rps_list[:-1])
    print("Computer choice", comp_choice)


    user_choice = string_checker("Choose: ", rps_list)
    print("you chose", user_choice)


    if user_choice == "xxx":
        break



    result = rps_compare(user_choice, comp_choice)
    print(f"{user_choice} vs {comp_choice}, {result}")

    rounds_played += 1

# if users are in infinite mode, increase number of rounds
    if mode == "infinite":
        num_rounds += 1


# game loop ends here

# Game History
# Automated testing is below in the form (test_case, expected_value)