bob

users = [{'user': "Bob", 'pass': "Bobbo1980"}, {'user': "Jim", 'pass': "JimmyBest"}]



#encryption
def encryption():
    charin = input(">")
    num = ord(charin)
    num += 3
    print(chr(num))

encryption()







#add a new user
def new_user():
    decision = ''
    user = ''
    password = ''
    userlist = []
    while decision == '':
        decision = input("Do you want to add a new user?('y' or 'n')")
        if decision == 'n':
            return False
        if decision == 'y':
            print("Enter a name for the new user: ")
            user = input()
            for n in range(0, len(users)):
                if user == users[n]['user']:
                    print("Username taken")
                    decision = ''
                    break
                else:
                    password = password_change()
                users.append({'user': user, 'pass': password})
                print("User sucusfully added.")
                print(users)
                return True





        else:
            print("enter 'y' for yes  and 'n' for no")
            decision = ''




#changing password
def password_change():
    password = ''
    passwordcorrect = False
    repeat = False
    rep = ''
    capitals = 0
    lowers = 0
    while passwordcorrect == False:
        password = input("Enter a new password: ")
        for n in password:
            if n in "PYFGCRLAOEUIDHTNSQJKXBMWVZ":
                capitals += 1
            if n  in "pyfgcrlaoeuidhtnsqjkxbmwvz":
                lowers += 1
        if capitals >= 1 and lowers >= 1 and len(password) >= 8:
            passwordcorrect = True
            print ("Valid passowrd")
            while repeat == False:
                rep = input("repeat password: ")
                if rep == password:
                    repeat = True
                    print("Password susussfully changed")
                    break

        else:
            print("Make sure your password has at least one capital, one lower-case and is at least 8 char long.")
            capitals = 0
            lowers = 0
            passwordcorrect = False
    return password


#change and return password
def change(string):
    password = ''
    while password != string:

        password = input("Enter your old password: ")
        if password == string:
            print("Success")
            return password_change()
        else:
            password = ''
            print("Password is incorect. Try again. ")


#log in
def log_in():
    user = ''
    password = ''
    chang = ''
    while user == '':
        user = input("Enter username: ")
        for n in range(0, len(users)):
            if users[n]['user'] == user:
                print("User in database! Enter password for " + user + ": ")
                while  password == '':
                    password = input("password: ")
                    if password == users[n]['pass']:
                        print("Loged in.")
                        while chang != 'y' or chang != 'n':
                            print("Do you want to change password?('y' or 'n')")
                            chang = input()
                            if chang == 'y':
                                users[n]['pass'] = change(users[n]['pass'])
                                print("New password of a user: " + users[n]['user'] + " is " + users[n]['pass'])
                                break
                            if chang == 'n':
                                print("Quiting to menu...")
                                main()


                    else:
                        print("Incorrect password")
                        password = ''

                break
        else:
            print("No user with such a name")
            if new_user() == False:
                user = ''
                print("Enter an existing username")
            else:
                user = ''

#main menu
def main():
    choice = 0
    print("Welcome! Select action: ")

    while choice == 0:

        print("    1. Log in")
        print("    2. Add a user")
        print("    3. List users")
        try:
            choice = int(input())
            if choice == 1:
                log_in()
            if choice == 2:
                new_user()
                choice = 0
            if choice == 3:
                for n in range(0,len(users)):
                    print(users[n]['user'])
                    choice = 0


        except ValueError:
            print("Invalid input. Try again.")
            choice = 0




main()