blackjack.py

import random, sys

HEARTS = chr(9829)
DIAMONDS = chr(9830)
SPADES = chr(9824)
CLUBS = chr(9827)
BACKSIDE = 'backside'


def main():
    print(
        '''
        Rules:
            Try to get as close to 21 without going over.
            Kings, Queens, and Jacks are worth 10 points.
            Aces are worth 1 or 11 points,
            Cards 2 through 10 are worth their face value.
            (H)it to take another card.
            (S)tand to stop taking cards.
            On your first play, you can (D)ouble down to increase your bet but must hit exactly one more time before standing.
            In case of a tie, the bet is returned to the player.
            The dealer stops hitting at 17.
        '''
    )

    money = 5000

    while True:
        if money <= 0:
            print("You're broke!")
            print("Good thing you weren't playing with real money.")
            print('Thanks for playing!')
            sys.exit()

        print('Money:', money)
        bet = getBet(money)

        deck = getDeck()
        dealerHand = [deck.pop(), deck.pop()]
        playerHand = [deck.pop(), deck.pop()]

        print('Bet:', bet)
        while True:
            displayHands(playerHand, dealerHand, False)
            print()

            if getHandValue(playerHand) > 21:
                break

            move = getMove(playerHand, money - bet)

            if move == 'D':
                additionalBet = getBet(min(bet, (money - bet)))
                bet += additionalBet
                print('Bet increased to {}.'.format(bet))
                print('Bet:', bet)

            if move in ('H', 'D'):
                newCard = deck.pop()
                rank, suit, = newCard
                print('You drew a {} of {}.'.format(rank, suit))
                playerHand.append(newCard)

                if getHandValue(playerHand) > 21:
                    continue

            if move in ('S', 'D'):
                break

        if getHandValue(playerHand) <= 21:
            while getHandValue(dealerHand) < 17:
                print('Dealer hits...')
                dealerHand.append(deck.pop())
                displayHands(playerHand, dealerHand, False)

                if getHandValue(dealerHand) > 21:
                    break
                input('Press Enter to continue')
                print('\n\n')

        displayHands(playerHand, dealerHand, True)

        playerValue = getHandValue(playerHand)
        dealerValue = getHandValue(dealerHand)

        if dealerValue > 21:
            print('Dealer busts! You win ${}!'.format(bet))
            money += bet
        elif (playerValue > 21) or (playerValue < dealerValue):
            print('You lost')
            money -= bet
        elif playerValue > dealerValue:
            print('You won ${}!'.format(bet))
            money += bet
        elif playerValue == dealerValue:
            print('It\'s a tie, the bet is returned to you.')

        input('Press Enter to continue...')
        print('\n\n')


def getBet(maxBet):
    while True:
        print('How much do you bet? (1-{}, or QUIT)'.format(maxBet))
        bet = input('> ').upper().strip()
        if bet == 'QUIT':
            print('Thanks for playing!')
            sys.exit()

        if not bet.isdecimal():
            continue

        bet = int(bet)
        if 1 <= bet <= maxBet:
            return bet


def getDeck():
    deck = []
    for suit in (HEARTS, DIAMONDS, SPADES, CLUBS):
        for rank in range(2, 11):
            deck.append((str(rank), suit))
        for rank in ('J', 'Q', 'K', 'A'):
            deck.append((rank, suit))
    random.shuffle(deck)
    return deck


def displayHands(playerHand, dealerHand, showDealerHand):
    print()
    if showDealerHand:
        print('DEALER:', getHandValue(dealerHand))
        displayCards(dealerHand)
    else:
        print('DEALER: ???')
        displayCards([BACKSIDE] + dealerHand[1:])

    print('PLAYER:', getHandValue(playerHand))
    displayCards(playerHand)


def getHandValue(cards):
    value = 0
    numberOfAces = 0

    for card in cards:
        rank = card[0]
        if rank == 'A':
            numberOfAces += 1
        elif rank in ('K', 'Q', 'J'):
            value += 10
        else:
            value += int(rank)

    value += numberOfAces
    for i in range(numberOfAces):
        if value + 10 <= 21:
            value += 10

    return value


def displayCards(cards):
    rows = ['', '', '', '', '']

    for i, card in enumerate(cards):
        rows[0] += ' ___  '
        if card == BACKSIDE:
            rows[1] += '|## | '
            rows[2] += '|###| '
            rows[3] += '|_##| '
        else:
            rank, suit = card
            rows[1] += '|{} | '.format(rank.ljust(2))
            rows[2] += '| {} | '.format(suit)
            rows[3] += '|_{}| '.format(rank.rjust(2, '_'))

    for row in rows:
        print(row)


def getMove(playerHand, money):
    while True:
        moves = ['(H)it', '(S)tand']

        if len(playerHand) == 2 and money > 0:
            moves.append('(D)ouble down')

        movePrompt = ', '.join(moves) + '> '
        move = input(movePrompt).upper()
        if move in ('H', 'S'):
            return move
        if move == 'D' and '(D)ouble down' in moves:
            return move


if __name__ == '__main__':
    main()

'''Exploring the Program

How does the program represent a single card?
    If the player chooses to Hit or Double, a newCard variable is made that is used to pop one more card from the deck and append it to the player hand. If the player's hand is less than or equal to a value of 21, the dealer will hit and a new card from the deck is appended to the dealer hand.

How does the program represent a hand of cards?
    A hand of cards is represented by the variables dealerHand and playerHand. These variables pop two cards from the card deck to give to the dealer and player, respectively.

What do each of the strings in the rows list represent?
    The characters that make up each row
    
What happens when showDealerHand in the displayHands() function is set to True? What happens when it is False?
'''