#1234 is the pin number, if you type any other number it will return you to beginning

BALANCE =0

def get_balance():
    see = raw_input("Enter 'y' for yes or 'n' for no: ")
    if (see == "Y") or (see == "y"):
        print ("Current balance: " + str(BALANCE))
    else:
        return
    
def deposit():
    global BALANCE
    Amount = input("Enter amount to deposit: ")
    print ("Amount to be deposited:" , Amount)
    
    print ("Before balance :", BALANCE)
    BALANCE = Amount + BALANCE
    print ("After balance :", BALANCE)
    

def withdraw():
    global BALANCE
    Amount = input("Enter amount to withdraw: ")
    print ("Amount to be withdraw:" , Amount)
    
    print ("Before balance :", BALANCE)
    if(Amount>BALANCE):
        BALANCE =BALANCE - Amount
    else:
        BALANCE =Amount-BALANCE
   
    print ("After balance :", BALANCE)
   

def verify_pin(pin):
    if pin == 1234:
        print("Log in Successful")
        return True
    else:
        
        while(pin != 1234):
            print "It's not confirmed, please try again."
            pin = int(raw_input("Please enter your account pin number: "))
            if (pin ==1234):
                print("Log in Successful")
                return True
            

def show_instructions():
    """
    This function shows the instruction to the user how to operate the program.     [PURPOSE]
    """
    print"Type any of the following alphabet now for the following operation."
    print"'b' for Balance"
    print"'d' for Deposit"
    print"'w' for Withdraw"
    print"'q' for Quit"


def end():
    print("Thank you for Banking with Bank of Temple, goodbye!")
    exit()

    
def main():
    pinCheck = False
    print ("Hello, welcome to Bank of Temple!")
    pin = int(raw_input("Please enter your account pin number: "))
    pinCheck = verify_pin(pin)
    show_instructions()
    choice=raw_input("Enter your choice :")
    while(pinCheck):
        
        while (choice=='b' or choice=='B'):
            print"Are you sure that you want to see your account balance?"
            get_balance()
            show_instructions()
            choice=raw_input("Enter your choice :")
        while (choice=='d' or choice=='D'):
            print"Are you sure you want to deposit money?"
            deposit()
            show_instructions()
            choice=raw_input("Enter your choice :")
        while (choice=='w' or choice=='W'):
            print"Are you sure you want to withdraw money?"
            withdraw()
            show_instructions()
            choice=raw_input("Enter your choice :")
        while (choice=='q' or choice=='Q'):
            print"YOU WANT TO QUIT"
            confirm = raw_input("If you agree, enter 'y' if not enter 'n': ")
            if confirm == 'y':
                end()
            elif confirm == 'n':
                show_instructions()
                choice=raw_input("Enter your choice :")
       
#IF YOU TYPE ANY OTHER "LETTER" THEN THE CODE WILL BREAK! WE WANTED IT LIKE THIS 
#SO THAT, LIKE A REAL COMPUTER SYSTEM, IF IT WERE A COMPUTER/HACKER THEY WOULD BE 
#LOCKED OUT OF THE PROGRAM   
        

main()