ms-dos.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import curses
import sys

def curses_wrapper(func, *args, **kwds):
    """Wrapper decorator that initializes curses and calls another function,
    restoring normal keyboard/screen behavior on error or exit.

    See curses.wrapper() for more info.
    """

    def decorated(*args, **kwds):

        try:
            screen = curses.initscr()
            curses.noecho()
            curses.cbreak()
            screen.keypad(1)

            try:
                curses.start_color()
            except:
                pass

            return func(screen, *args, **kwds)

        finally:
            if 'screen' in locals():
                screen.keypad(0)
                curses.echo()
                curses.nocbreak()
                curses.endwin()

    return decorated


def make_win(*args, width=2, height=2, pos_x=0, pos_y=0):
    """Wrapper to fix coordinate order in curses.newwin()"""

    # Enable "WxH" shortcut string
    if len(args) == 1 and "x" in args[0].lower():
        width, height = map(int, args[0].split("x"))

    return curses.newwin(height, width, pos_y, pos_x)


def dialog(screen, *args, title=None, message=None, shadow=True, **kwargs):
    """Build dialog boxes centered on screen

    :screen:    base screen on which to center dialog
    :title:     dialog title text
    :message:   dialog message text

    """

    # Set up window dimensions

    height          = kwargs.get("height", 8)
    width           = kwargs.get("width", 32)
    max_h, max_w    = screen.getmaxyx()
    x_offset        = (max_w - width) // 2
    y_offset        = (max_h - height) // 2

    # Draw shadow

    if shadow:
        shadow = make_win(
                *args,
                width=width,
                height=height,
                pos_x=x_offset+1,
                pos_y=y_offset+1,
                **kwargs
                )
        shadow.bkgd(" ", curses.color_pair(1))

    window = make_win(
            *args,
            width=width,
            height=height,
            pos_x=x_offset,
            pos_y=y_offset,
            **kwargs
            )

    window.bkgd(" ", curses.color_pair(3))
    window.box()

    # Place message in a subwindow for proper text wrap
    sub_win = window.derwin(height - 2, width - 2, 1, 1)

    if title:
        # Center title
        title_x_offset = (width - len(title)) // 2
        window.addstr(0, title_x_offset, title)

    if message:
        sub_win.addstr(0, 0, message)

    return window, ( shadow if shadow else None )


@curses_wrapper
def main(screen):
    """Main curses function

    :screen: screen provided by the wrapper decorator
    """

    # Setup some colors
    curses.init_pair(1, curses.COLOR_WHITE, curses.COLOR_BLACK)
    curses.init_pair(2, curses.COLOR_BLACK, curses.COLOR_BLUE)
    curses.init_pair(3, curses.COLOR_BLACK, curses.COLOR_MAGENTA)

    # Initialize screen
    screen.bkgd(" ", curses.color_pair(2))
    screen.clear()
    screen.refresh()

    win, wsh = dialog(
            screen,
            title="MS-DOS",
            message="Microsoft MS-DOS 7.10 Setup\n\nPlease wait...")

    wsh.refresh()
    win.refresh()

    screen.getkey()

    sys.exit(0)


if __name__ == "__main__":
    main()