An improved version of Rock, Paper, Scissors.

rps.py

"""Rock, Paper, Scissors.

There are two playing modes: user vs computer, and computer vs computer.
The game will continue until one player reaches a set score number.
Finally the user can decide whether to start a new game.

2018-03
"""

import random
import time

# Rock, Paper, Scissors:
RPS = ("Rock", "Paper", "Scissors")

# Score required to win the game:
MAX_SCORE = 3

# Length of pauses between game sections.
# Change this value to make the game faster or slower:
SECONDS = 1.5


class RockPaperScissors():
    """A two-way game of Rock, Paper, Scissors."""

    def __init__(self):
        """Initialize attributes."""
        self.new_game = True
        self.round_counter = 0
        self.players = {}
        for player_key in ("player1", "player2"):
            self.players[player_key] = {
                "hand": "",
                "score": 0,
                "human": False,
                "name": None,
                }
        # Let user choose playing mode.
        self.choose_mode()

    def choose_mode(self):
        """Ask if a human will play, and set attributes accordingly."""
        print("Hello, human! Make your choice:")
        print("\n1) Human vs Computer")
        print("2) Computer vs Computer")
        choice = ""
        while (choice not in "12") or (len(choice) != 1):
            choice = input("\nPlease enter 1 or 2: ")
        player1, player2 = self.players.keys()
        if choice == "1":
            self.players[player1]["human"] = True
            self.players[player1]["name"] = "You"
            self.players[player2]["name"] = "Computer"
        else:
            self.players[player1]["name"] = "Player 1"
            self.players[player2]["name"] = "Player 2"

    def choose_forms(self):
        """Let the user make a choice, or choose a random number."""
        print(f"\n\n== ROUND {self.round_counter} ==")
        for player in self.players:
            # Human player:
            if self.players[player]["human"]:
                print()
                for number, form in enumerate(RPS, 1):
                    print(f"{number}) {form}")
                number = ""
                while (number not in "123") or (len(number) != 1):
                    number = input("\nPlease enter 1, 2, or 3: ")
                self.players[player]["hand"] = int(number) - 1
            # Computer player:
            else:
                self.players[player]["hand"] = random.randrange(3)

    def decide_round_winner(self):
        """Decide who wins."""
        player1, player2 = self.players.keys()
        p1_hand = self.players[player1]["hand"]
        p2_hand = self.players[player2]["hand"]

        if ((p1_hand == 0 and p2_hand == 2) or
                (p1_hand == 1 and p2_hand == 0) or
                (p1_hand == 2 and p2_hand == 1)):
            winner = player1
        elif ((p2_hand == 0 and p1_hand == 2) or
              (p2_hand == 1 and p1_hand == 0) or
              (p2_hand == 2 and p1_hand == 1)):
            winner = player2
        else:
            winner = None
        return winner

    def show_score(self):
        """Show both players' score."""
        print("\n\n== SCORE ==\n")
        for player in self.players.values():
            print(f"{player['name']}: {player['score']}")

    def decide_total_winner(self):
        """Show the total winner of this game."""
        total_winner = None
        for player, value in self.players.items():
            if value["score"] == MAX_SCORE:
                total_winner = player
        return total_winner

    def choose_new_game(self):
        """Ask whether to start a new game.

        If the answer is yes, set flag attribute and
        reset attributes.
        """
        answer = ""
        while (answer not in "yn") or (len(answer) != 1):
            answer = input("\nStart a new game? (y/n) ").lower()
        if answer == "y":
            new_game = True
            self.round_counter = 0
            for player in self.players.values():
                player["score"] = 0
        else:
            new_game = False
        return new_game

    def play(self):
        """Start game loop and call game methods."""
        print("\n== Welcome to ROCK, PAPER, SCISSORS! ==\n")
        print(f"The game will end when a player has won {MAX_SCORE} times.")
        input("Press ENTER to begin. ")

        while self.new_game:

            # Raise round counter.
            self.round_counter += 1

            # Let the players choose their forms.
            self.choose_forms()

            # Decide the round winner.
            round_winner = self.decide_round_winner()

            # Show the players' choices.
            print()
            for player in self.players.values():
                time.sleep(SECONDS)
                print(f"{player['name']} chose: {RPS[player['hand']]}")

            # Show who has won this round or whether it was a tie.
            # Raise the winner's score.
            if round_winner:
                time.sleep(SECONDS)
                print(f"{self.players[round_winner]['name']} won!")
                self.players[round_winner]["score"] += 1
            else:
                time.sleep(SECONDS)
                print("It's a tie!")

            # Show the players' score.
            time.sleep(SECONDS)
            self.show_score()

            # Check if a player has reached the maximum score number.
            # If so, declare the total winner.
            total_winner = self.decide_total_winner()
            if total_winner:
                total_winner_name = self.players[total_winner]["name"]
                print(f"\n* Winner: {total_winner_name} *".upper())

                # Ask whether the user wants to start a new game.
                print()
                time.sleep(SECONDS)
                self.new_game = self.choose_new_game()

        print("\nGoodbye, human. Until next time.")


def main():
    """Create game object and start its play() method."""
    rps_game = RockPaperScissors()
    rps_game.play()

if __name__ == "__main__":
    main()