Blackjack Program charges player twice after game

Question

Here's the code for my blackjack game that uses PySimpleGUI.

# import PySimpleGUI as sg
import random
import PySimpleGUI as sg
import time

sg.theme('DarkAmber')

player_money = 1500
player_cards = []
player_value = 0
computer_cards = []
computer_value = 0
bet = 0
count = 0
end = 0

# Function to calculate quadratic equation properties
def get_card():
    global player_cards
    card = random.randint(1, 13)
    if card == 1:
        card = 11
    elif card == 11 or card == 12 or card == 13:
        card = 10
    return card
            
def start_game():
    global player_cards
    global computer_cards
    global player_value
    global computer_value
    player_value = 0
    computer_value = 0
    player_cards = []
    computer_cards = []
    for i in range(4):
        card = get_card()
        if i % 2 == 0:
            player_cards.append(card)
            player_value += card
        else:
            computer_cards.append(card)
            computer_value += card
    # if player_value >= 21:
    #     stand()
            
def check_value(list):
    count = 0
    for i in list:
        count += i
    return count


def print_cards():
    print(F"player cards: {player_cards}")
    print(F"your cards add up to {check_value(player_cards)}.")
    print(F"computer cards: [{computer_cards[0]}, ---]")


def deal():
    global player_cards
    global player_value
    card = get_card()
    player_cards.append(card)
    player_value += card

def comp_deal():
    global computer_cards
    global computer_value
    card = get_card()
    computer_cards.append(card)
    computer_value += card

def button_swap(list, e1, e2):
    list[e1].update(visible=False)
    list[e1].update(disabled=True)
    list[e2].update(visible=True)
    list[e2].update(disabled=False)
    
def show_comp():
    global window
    global computer_cards
    global computer_value
    window["cc"].update(F"Dealer cards: {computer_cards}")
    window["cv"].update(F"The value of the dealers cards: {computer_value}")


def check_win():
    global player_value
    if player_value >= 21:
        stand()

def results():
    global player_value
    global computer_value
    global window
    global player_money
    global bet
    global count
    global event
    global end
    end = 0
    bet = int(bet)
    if player_value > 21:
        player_money -= bet
        window['results'].update(F"You lost ${bet} and now have {player_money}.")
    elif computer_value > 21:
        player_money += bet
        window['results'].update(F"You won ${bet} and now have {player_money}!")
    else:
        if player_value > computer_value:
            player_money += bet
            window['results'].update(F"You won ${bet} and now have {player_money}!")
        elif player_value == computer_value:
            window['results'].update("You tied, so you got your bet back.")
        else:
            player_money -= bet
            window['results'].update(F"You lost ${bet} and now have {player_money}.")
    window['Deal'].update(disabled=True)  # Disable the "Deal" button
    window['Stand'].update(disabled=True)  # Disable the "Stand" button
    # if player_money == 0:
    #     window["restart"].update("You're out of money. Bye!")
    #     button_swap(window, "Deal", "Quit")
    #     window["Stand"].update(visible=False)

    # else:
    window["restart"].update("Play again?")
    button_swap(window, "Deal", "Yes")
    button_swap(window, "Stand", "No")
    window["intro"].update(F"Your current money: ${player_money}")
    
def end_game():
    global player_value
    global computer_value
    global window
    global player_money
    global bet
    global count
    show_comp()
    results()
    count += 1
    print(count)

def stand():
    global player_value
    global computer_value
    global window
    global player_money
    global bet
    global count
    if player_value <= 21:
        while computer_value < player_value:
            comp_deal()
    end_game()
            

start_game()

layout1 = [
    [sg.Text("Welcome to blackjack!")],
    [sg.Text(F"Your cards: {player_cards}", key='pc')],
    [sg.Text(F"The value of your cards: {player_value}", key='pv')],
    [sg.Text(F"Dealer cards: [{computer_cards[0]}, ---]", key="cc")],
    [sg.Text("", key="cv")],
    [sg.Text("", key="results")],
    [sg.Text("", key="restart")],
    [sg.Button("Deal"), sg.Button("Stand"),
     sg.Button("Yes", visible=False, disabled=False), sg.Button("No", visible=False, disabled=False)]
]

def update_layout():
    global window
    window['pc'].update(F"Your cards: {player_cards}")
    window['pv'].update(F"The value of your cards: {player_value}")
    window['cc'].update(F"Dealer cards: [{computer_cards[0]}, ---]")
    window['cv'].update("")
    window['results'].update("")
    window["restart"].update('')
    button_swap(window, "Yes", "Deal")
    button_swap(window, "No", "Stand")


def error_trap(num):
    global window
    global player_money
    result = True
    try:
        int(num)
    except ValueError:
        window["error"].update("Number not entered. Please try again.")
        return False
    if int(num) > player_money:
        window["error"].update("You don't have that much money. Please try again.")
        result = False
    elif int(num) <= 0:
        window["error"].update("Please input actual money.")
    return result
    

layout2 = [
    [sg.Text(F"Your current money: ${player_money}", key="intro")],
    [sg.Text("How much would you like to bet on this round?")],
    [sg.InputText("50", key="money")],
    [sg.Text("", key="error")],
    [sg.Button("Start"), sg.Button("Quit")]
]

layout = [[sg.Column(layout1, visible=False, key="-COL1-"), sg.Column(layout2, visible=True, key="-COL2-")]] 

window = sg.Window("the box", layout)

while True:

    event, values = window.read()
    check_win()

    if event == "Deal":
        deal()
        window['pc'].update(F"Your cards: {player_cards}")
        window['pv'].update(F"The value of your cards: {player_value}")
        check_win()
        
        
    elif event == "Stand":
        stand()
         

    elif event == "Yes":
        window['-COL1-'].update(visible=False)
        window['-COL2-'].update(visible=True)

    elif event == "Start":
        bet = window["money"].get()
        i = error_trap(bet)
        if i == True:
            window['-COL2-'].update(visible=False)
            window['-COL1-'].update(visible=True)
            if count != 0:
                start_game()
                update_layout()

window.close()

I can't seem to figure out why if the player wins, they win their money twice, or if they lose, they lose their money twice. The second charge happens whenever the player says 'yes' or 'no' to play again.

Answer 1

In the main loop, You call check_win() unconditionally. You also call stand() to handle an event. However, one of the main things check_win() does is to also call stand().

def check_win():
    global player_value
    if player_value >= 21:
        stand()

The method stand() calls end_game() which calls results(). The method results() then updates player_money.

The net effect is that there are situations where there are ultimately multiple calls to the method that updates the player ballance.