import random

#check hat 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 res[onse 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 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 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 infinite 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)

#compares user / computer choice and returns
#result (win / lose tie)


def rps_compare(user, comp):

    # if the user and the computer choice is the same, its a tie

    if user == comp:
        round_result = "Tie"

    # there are three ways to win
    elif user == "paper" and comp == "rock":
        round_result = "Player wins!"
    elif user == "scissors" and comp == "paper":
        round_result = "Player wins!"
    elif user == "rock" and comp == "scissors":
        round_result = "Player wins!"

    #if its not a win / tie, then its a loss
    else:
        round_result = "Computer wins"

    return round_result


#Main routine starts here

#intialise game variables
mode = "regular"

rounds_played = 0
rounds_tried = 0
rounds_lost = 0

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

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":
    print('''

    *** Instructions ****

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

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

    The rules are as follows:
    - Paper beats Rock
    - Rock beats scissors
    - Scissors beats paper
    
    Press <xxx> to end the game at anytime.

    Good Luck!
        ''')

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

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

    #if user choice is the exit code, break the loop
    if user_choice == "xxx":
        break

    result = rps_compare(user_choice, comp_choice)

    #adjust game lost / game tried counters add results to the game history
    if result == "Tie":
        rounds_tried += 1
        feedback = "It's a tie!"
    elif result == "Computer wins":
        rounds_lost += 1
        feedback = "Computer wins!"
    else:
        feedback = "You won!"

    #set up round feedback and output it user.
    #add it to the game history list (include the round number)
    round_feedback = f"{user_choice} vs {comp_choice}, {feedback}"
    history_item = f"Round: {rounds_played + 1} - {round_feedback}"

    print(round_feedback)
    game_history.append(history_item)


    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

if rounds_played > 0:
    #calclate statistcs
    rounds_won = rounds_played - rounds_tried - rounds_lost
    percent_won = rounds_won / rounds_played * 100
    percent_lost = rounds_lost / rounds_played * 100
    percent_tied = 100 - percent_won - percent_lost

    #outut game statistics
    print("Game Statistices")
    print(f"Won: {percent_won:.2f} \t "
          f"Lost: {percent_lost:.2f} \t "
          f"Tied: {percent_tied:.2f}")

    #ask user if they want to see their game history and output if requested.
    see_history = string_checker("\nDo you want to see your game history? ")
    if see_history == "yes":
        for item in game_history:
            print(item)

    print()
    print("Thanks for playing.")

else:
    print("Oops - You chickened out!")