#!/usr/bin/python3

# The MIT License (MIT)
#
# Copyright © 2020-2025 pacman64
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the “Software”), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.


# countdown.pyw [minutes...]
#
# Show a small window with a live second-by-second countdown you can
# change/restart any time using the slider control. When not given a
# number, the default first duration to count down from is 20 minutes.
#
# Keyboard shortcuts:
#
#   esc         ->  quit
#   right arrow ->  restart countdown using 1 more minute
#   left arrow  ->  restart countdown using 1 fewer minute


from sys import argv
from typing import Any
from datetime import datetime
from tkinter import Tk, Label, Scale, TOP, BOTTOM, HORIZONTAL


minutes = 20  # how many minutes to count down from
timer = ''  # timer id to allow cancelling
start = datetime.now()  # to determine the time left every second

# handle optional cmd-line arg to change default countdown minutes
if len(argv) > 1:
    try:
        n = int(argv[1])
        if n > 0:
            minutes = n
    except Exception:
        pass


def check_key(event: Any) -> None:
    char: str = event.char
    # quit when esc key is pressed
    if char != '' and ord(char) == 27:
        win.quit()


def restart():
    global timer, minutes, start
    # don't force main window on top while a countdown is happening
    win.attributes('-topmost', False)

    m = 0
    try:
        m = float(input.get())
    except Exception:
        m = 20
    minutes = m

    if timer != '':
        win.after_cancel(timer)
    start = datetime.now()
    tick()


def tick() -> None:
    global timer
    diff = datetime.now() - start
    sl = 60 * minutes - diff.total_seconds()  # seconds left

    if sl < 0:
        # ensure main window is showing when countdown is over
        win.attributes('-topmost', True)
        output.configure(text='done')
        # returning prevents any further scheduled callback
        return

    output.configure(text=f'{int(sl/60):02d}:{int(sl%60):02d}')
    timer = win.after(1000, tick)


win = Tk()
win.title('Countdown')
win.resizable(False, False)
win.bind('<KeyPress>', check_key)

input = Scale(win, from_=1, to=90, orient=HORIZONTAL)
input.configure(command=lambda _: restart())
input.pack(side=TOP, padx=5)
input.set(minutes)
input.focus()

font = ('Lucida Console', 72)
output = Label(text='', font=font)
output.pack(side=BOTTOM, padx=10, pady=5)
tick()

win.mainloop()