treewatch.py

#!/usr/bin/env python3

from argparse import ArgumentParser
from pathlib import Path
from textwrap import indent
import curses
import unicodedata

FOLDER_OPEN = unicodedata.lookup('Open File Folder')
FOLDER_CLOSED = unicodedata.lookup('File Folder')
DOCUMENT = unicodedata.lookup('Page Facing Up')
PAD = '    '
PREPAD = '  '

def exit_on_ctrl_c(f):
    'Decorator to nicely exit on Control-C'
    def f_inner(*args, **kargs):
        try:
            f(*args, **kargs)
        except KeyboardInterrupt:
            pass
    return f_inner

def python_tree(directory, level, current=0):
    'Make a unicode tree'
    results = ''
    for f in sorted(directory.iterdir()):
        results += PAD
        results +=  DOCUMENT if not f.is_dir() else FOLDER_OPEN if current < level else FOLDER_CLOSED
        results += f' {f.name}\n'
        if f.is_dir() and current < level:
            results += indent(python_tree(f, level, current+1), PAD)
    return results


parser = ArgumentParser(description='Watch for files')
parser.add_argument('-L', type=int, default=1,
                    help='Depth to print')
args = parser.parse_args()

@curses.wrapper
@exit_on_ctrl_c
def main(stdscr):
    curses.halfdelay(5) # 5/10 of a second refresh
    while(True):
        stdscr.clear()
        stdscr.addstr(1, 0, PREPAD + FOLDER_OPEN + ' ' + Path('.').resolve().name)
        stdscr.addstr(2, 0, indent(python_tree(Path('.'), args.L), PREPAD))
        
        stdscr.addstr(curses.LINES - 2, 0, "Press a number or arrow keys to change levels shown.")
        stdscr.addstr(curses.LINES - 1, 0, "Press any other key or Control-C to exit.")

        try:
            new_l = stdscr.getkey()
            if new_l in ('KEY_UP', 'KEY_LEFT'):
                new_l = max(args.L - 1, 0)
            elif new_l in ('KEY_DOWN', 'KEY_RIGHT'):
                new_l = args.L + 1
            args.L = int(new_l)
        except curses.error:
            pass
        except ValueError:
            return