#!/usr/bin/env python3
# -*- encoding: utf-8 -*-

import json
import tkinter
import traceback
from io import BytesIO
from pathlib import Path
from typing import Optional

from PIL import Image, ImageTk

millisamount = 10

AnyInt = Optional[int]


class MainApp(tkinter.Tk):
    def __init__(self):
        super().__init__()
        self.geometry('500x500')
        self.known_width = 500
        self.known_height = 500
        self.resizable(width=True, height=True)
        self.photo = Image.new('RGB', (256, 256), (0, 0, 0))
        self.display_photo = self.photo.copy()
        self.image = ImageTk.PhotoImage(self.display_photo)
        self.frame = tkinter.Frame(self)
        self.frame.pack(fill=tkinter.BOTH, expand=tkinter.YES)
        self.panel = tkinter.Label(self.frame)
        self.panel.pack(fill=tkinter.BOTH, expand=tkinter.YES)
        self.panel.bind('<Configure>', self._resize_image)
        self.panel.configure(image=self.image)
        self.update()
        self._resize_image2()
        self.update()

    def _resize_image(self, event):
        self.known_width = event.width
        self.known_height = event.height
        self._resize_image2()

    def _resize_image2(self):
        size_tuple = (self.known_width, self.known_height)
        self.display_photo = self.photo.copy()
        self.display_photo.thumbnail(size_tuple)
        if self.display_photo is None:
            self.display_photo = self.photo
        self.image = ImageTk.PhotoImage(self.display_photo)
        self.panel.configure(image=self.image)

    def update_image(self, image, windowTile=None):
        if windowTile is not None:
            self.winfo_toplevel().title(str(windowTile))
        self.photo = image
        self._resize_image2()
        self.update()


def updateImage(tk: MainApp, old_fpp_modified: AnyInt):
    try:
        file_path_path = Path('latest_image_download.txt')
        new_fpp_modified = None
        try:
            st = file_path_path.stat()
            new_fpp_modified = st.st_mtime_ns
        except BaseException:
            pass
        tk.after(millisamount, updateImage, tk, new_fpp_modified)
        if old_fpp_modified != new_fpp_modified:
            file_path = None
            info_path = None
            file = None
            info = None
            try:
                fpp = file_path_path.read_text()
                file_path = Path(fpp)
                info_path = Path(fpp+'.json')
                file = file_path.read_bytes()
                info = json.loads(info_path.read_text())
            except BaseException:
                pass
            if file is not None and info is not None:
                try:
                    tk.update_image(
                        Image.open(BytesIO(file)),
                        info.get('url', str(file_path).split('/', 1)[-1])
                    )
                except BaseException:
                    print()
                    print("Exception on entry %r" % file_path)
                    traceback.print_exc()
        if (old_fpp_modified is not None and new_fpp_modified is None):
            tk.destroy()
    except BaseException:
        print()
        traceback.print_exc()
        tk.destroy()


def main():
    tk = MainApp()
    tk.after(1, updateImage, tk, None)
    tk.mainloop()


if __name__ == '__main__':
    main()