#!/usr/bin/python
''' handle gui button related commands.'''

import ri_tk
import ri_seq
import ri_widget

def quit():
    ''' correspond to quit button '''
    ri_tk.quit()

def previous():
    ''' correspond to previous button '''
    if 'current_window' in dir(ri_tk):
        ri_tk.kill_widget(ri_tk.current_window)

    wid_name = ri_seq.previous()
    if wid_name is not None:
        ri_tk.display_widget(ri_widget.Widget.dict[wid_name])

def next():
    ''' correspond to next button '''
    if 'current_window' in dir(ri_tk):
        ri_tk.kill_widget(ri_tk.current_window)

    wid_name = ri_seq.next()
    if wid_name is not None:
        ri_tk.display_widget(ri_widget.Widget.dict[wid_name])