import sys
clients = ''

def add_client(client_name):
    global clients
    
    if client_name.upper() not in clients.upper():
        clients += client_name
        _add_coma()
    else:
        print("The client already exist!!")


def update_client(client_name,name_update):
    global clients
    
    if client_name.upper() in clients.upper():
        clients = clients.replace(client_name,name_update)
    else:
        print("The client not exist!!")


def search_client(client_name):
    global clients

    client_list = clients.split(',')
    for client in client_list:
        if client != client_name:
            continue
        else:
            return True


def delete_client(client_name):
    global clients
    
    if client_name.upper() in clients.upper():
        clients = clients.replace(client_name+',','')
    else:
        print("The client not exist!!")


def _add_coma():
    global clients
    clients += ','

def list_client():
    global clients
    print(clients)

def _get_client_name():
    client_name = None
    while not client_name:
        client_name =  input("What's client Name? ")
        if client_name == 'exit':
            client_name == None
            break
    if not client_name:
        sys.exit()
    return client_name



def _print_welcome():
    mesaje ="""
        WELCOME TO PLATZI VENTAS
        '*'*50
        What would you lke to do today?
        [C] Create Client
        [L] List Client
        [D] Delete Client
        [U] Update Client
        [S] Search Client
        [E] Salir
        : """
    option  = input(mesaje)
    return option

if __name__ == "__main__":
    
    active = True

    while active:

        option = _print_welcome()
        if option == 'L' or option == 'l':
            list_client()

        elif option == 'C' or option == 'c':
            name = _get_client_name()
            add_client(name)
            list_client()
        elif option == 'S' or option == 's':
            name = _get_client_name()
            found = search_client(name)
            if found:
                print('The client is in the client\'s list')
            else:
                print('The client: {} is not in our client\'s list'.format(name))

        elif option == 'U' or option == 'u':
            name = _get_client_name()
            name_update = input("What's name to update? ")
            update_client(name,name_update)
            list_client()
        elif option == 'D' or option == 'd':
            name = _get_client_name()
            delete_client(name)
            list_client()

        elif option == 'E' or option == 'e':
            active = False