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 the following list: {valid_ans}"

    while True:

        # Get user response and make sure its 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 the user response is the same as
            # 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()

# checks for an integer more than zero (allows <enter>)
def int_check(question):
    while True:
        error = "Please enter an integer that is 1 or more"

        to_check = input(question)

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

        try:
            response = int(to_check)

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

            else:
                return response

        except ValueError:
            print(error)

#displays instructions if the user inputs yes
def instructions():
    """Prints instructions"""

    print("""
*** Instructions ****

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

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

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

Press <xxx> to end the game at anytime.

Good Luck!
    """)


# 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 the user if they want instructions (yes/no)
want_instructions = string_checker("Do you want to see the instructions? ")

# Display the instructions if the user wants to see them...
if want_instructions == "yes":
    instructions()

# Ask the 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
    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)
    print()

    # get user choice
    user_choice = string_checker("Choose: ", rps_list)
    print("you chose", user_choice)

    # breaks the loop if the user inputs "xxx"
    if user_choice == "xxx":
        break

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

    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 / statistics area