#!/bin/env python3
import datetime
from tkinter import Tk, CENTER, Label
import click
import typing as t


class DateTime(click.DateTime):
    def _try_to_convert_date(self, value: t.Any, format: str) -> t.Optional[datetime]:
        try:
            if format == SECONDS and value[-1] == "s":
                return datetime.datetime.now() + datetime.timedelta(seconds=int(value[1:-1]))
            if format == MINUTES and value[-1] == "m":
                return datetime.datetime.now() + datetime.timedelta(minutes=int(value[1:-1]))
            if format == HOURS:
                return datetime.datetime.combine(
                    datetime.datetime.now().date(),
                    datetime.datetime.strptime(value, format).time()
                )
            return datetime.datetime.strptime(value, format)
        except ValueError:
            return None


SECONDS = '+%Ms'
MINUTES = '+%Mm'
HOURS = '%H:%M'
DATETIME_FORMAT = ['%Y-%m-%d', '%Y-%m-%dT%H:%M:%S', '%Y-%m-%d %H:%M:%S', '%Y-%m-%d %H:%M', HOURS, MINUTES, SECONDS]


@click.command()
@click.argument("enddate", type=DateTime(formats=DATETIME_FORMAT))
def main(enddate):
    root = Tk()
    root.geometry("300x100+200+200")
    root.configure(background="#000")
    tlbl = Label(root, text="", font=("Arial", -100), fg="#fff", bg="#000")
    tlbl.pack()
    tlbl.place(relx=.5, rely=.5, anchor=CENTER)

    def deltaStr(t):
        days, remainder = divmod(t.total_seconds(), 60 * 60 * 24)
        hours, remainder = divmod(remainder, 3600)
        minutes, seconds = divmod(remainder, 60)
        if days == 0:
            if hours == 0:
                if minutes == 0:
                    return f"{int(seconds):02d}"
                return f"{int(minutes):02d}:{int(seconds):02d}"
            return f"{int(hours):02d}:{int(minutes):02d}:{int(seconds):02d}"
        return f"{int(days):02d}:{int(hours):02d}:{int(minutes):02d}:{int(seconds):02d}"

    def resize(_):
        ratio = root.winfo_width() / 1920
        tlbl.configure(font=('Chicago', int(ratio * -200)))

    def update():
        delta = enddate - datetime.datetime.now()
        if delta.total_seconds() < 0:
            tlbl.configure(text="Now")
            tlbl.config(fg="red")
        else:
            tlbl.configure(text=deltaStr(delta))
        root.after(1000, update)

    root.bind("<Configure>", resize)
    root.bind("<Escape>", lambda x: root.destroy())
    root.after(1, update)
    root.wm_attributes('-type', 'splash')
    root.mainloop()


if __name__ == "__main__":
    main()