"""
Central place for flags, variables, small utilities etc. that determine
how Tk is used throughout IDLE.
"""

import tkinter


# Should IDLE use themed-Tk widgets (ttk)?
# Callers can set to False to force non-ttk widgets even when ttk is present.
using_ttk = False

# What windowing system are we using?
windowing_system = None     # will be set to 'aqua', 'win32', or 'x11'

# Do we need to include a Sizegrip widget? Yes on some older systems.
need_sizegrip = False

# Cursor to use to indicate clickable things, like links - usually a hand
clickable_cursor = None


class Spinbox(tkinter.Spinbox):
    """
    A ttk::spinbox was added in Tk 8.5.9; use it if present, otherwise
    use a spinbox. Note the two have different options and methods, so this
    only works for the basics.
    """
    def __init__(self, master=None, cnf={}, **kw):
        hasTtkSpinbox = master and master.tk.call('info', 'commands',
                                                  'ttk::spinbox')
        base = 'ttk::spinbox' if hasTtkSpinbox else 'spinbox'
        Widget.__init__(self, master, base, cnf, kw)


# Initialization our common variables; we need to start up a temporary
# Tk instance to do so

root = tkinter.Tk()     # If this fails, no meaningful recovery

try:
    from tkinter import ttk
    b = tkinter.ttk.Button(root)
    using_ttk = True
except Exception:
    pass

windowing_system = root.call('tk', 'windowingsystem')

clickable_cursor = 'pointinghand' if windowing_system == 'aqua' else 'hand2'

if windowing_system == 'aqua':
    import platform
    v, _, _ = platform.mac_ver()
    major, minor = v.split('.')[:2]
    if (int(major) == 10 and int(minor) < 7):
        need_sizegrip = True

root.after_idle(root.destroy)   # 'after' avoids some background errors