# Python imports
import os
import requests
import subprocess

# Lib imports
import gi
gi.require_version('Gtk', '3.0')
gi.require_version('GtkSource', '4')
from gi.repository import Gtk
from gi.repository import GLib
from gi.repository import GtkSource

# Application imports



class OCRWindow(Gtk.Window):
    def __init__(self):
        super(OCRWindow, self).__init__()

        self.tesseract_path = f"{settings.get_home_config_path()}/tesseract-ocr.AppImage"
        self.download_url   = "https://github.com/AlexanderP/tesseract-appimage/releases/download/v5.3.3/tesseract-5.3.3-x86_64.AppImage"

        self._setup_styling()
        self._setup_signals()
        self._subscribe_to_events()
        self._load_widgets()


    def _setup_styling(self):
        self.set_title(f"Tesseract OCR")
        self.set_icon_from_file( settings.get_window_icon() )
        self.set_gravity(5)  # 5 = CENTER
        self.set_position(1) # 1 = CENTER, 4 = CENTER_ALWAYS

        self.set_default_size(480, 600)
        self.set_size_request(480, 600)


    def _setup_signals(self):
        self.connect("delete-event", self._tear_down)

    def _subscribe_to_events(self):
        event_system.subscribe("show_ocr", self._show_ocr)

    def _load_widgets(self):
        scrolled_window = Gtk.ScrolledWindow()
        box             = Gtk.Box()
        download_button = Gtk.Button(label = "Download Tesseract OCR")
        run_ocr_button  = Gtk.Button(label = "Run OCR")
        text_view       = GtkSource.View()

        download_button.set_tooltip_text("Download Tesseract OCR")
        run_ocr_button.set_tooltip_text("Run OCR")

        download_button.connect("clicked", self._download_tesseract_ocr)
        run_ocr_button.connect("clicked", self._run_ocr_button)

        box.set_orientation(Gtk.Orientation.VERTICAL)
        text_view.set_vexpand(True)
        text_view.set_show_line_numbers(True)
        ctx = scrolled_window.get_style_context()
        ctx.add_class("container-padding-5px")

        scrolled_window.add(text_view)
        box.add(download_button)
        box.add(run_ocr_button)
        box.add(scrolled_window)
        self.add(box)

        box.show_all()

        if os.path.exists(self.tesseract_path):
            download_button.hide()
        else:
            run_ocr_button.hide()
            text_view.hide()


    def _show_ocr(self):
        self.show()

    def _tear_down(self, widget = None, eve = None):
        self.hide()

        # Return True to NOT propigate call (would actually destroy window n children)
        return True

    def _download_tesseract_ocr(self, button):
        parent           = button.get_parent()
        spinner          = Gtk.Spinner.new()

        parent.add(spinner)
        GLib.idle_add(self.__download_file, self.download_url, spinner)

    @daemon_threaded
    def __download_file(self, url = None, spinner = None):
        if not url: return
        if not spinner: return
        if not url == self.download_url: return

        spinner.show()
        spinner.start()
        
        # NOTE the stream = True parameter below
        with requests.get(url, stream = True) as r:
            r.raise_for_status()

            with open(self.tesseract_path, 'wb') as f:
                for chunk in r.iter_content(chunk_size = 8192):
                    # If chunk encoded response uncomment and set chunk_size parameter to None.
                    # if chunk:
                    f.write(chunk)

        spinner.stop()

        GLib.idle_add(self.__process_dl_finished, spinner)

    def __process_dl_finished(self, spinner = None):
        if not spinner: return
        
        parent           = spinner.get_parent()
        download_button, \
        run_ocr_button,  \
        text_view,       \
        spinner          = parent.get_children()

        parent.remove(spinner)
        if os.path.exists(self.tesseract_path):
            self.__set_as_executable(self.tesseract_path)
            run_ocr_button.show()
            text_view.show()
            download_button.hide()

    def __set_as_executable(self, tesseract_path):
        if not tesseract_path: return

        os.access(tesseract_path, os.X_OK)
        try:
            command = ["chmod", "544", tesseract_path]
            with subprocess.Popen(command, stdout = subprocess.PIPE) as proc:
                result = proc.stdout.read().decode("UTF-8").strip()
        except Exception as e:
            logger.error(f"Couldn't chmod\nFile:  {properties.file_uri}")
            logger.error( repr(e) )


    def _run_ocr_button(self, button):
        active_image = event_system.emit_and_await("get_active_image_path")

        if not active_image: return

        scrolled_window = button.get_parent().get_children()[2]
        text_view = scrolled_window.get_children()[0]

        command   = [self.tesseract_path, active_image, "stdout"]
        result    = subprocess.run(command, stdout = subprocess.PIPE)
        data      = result.stdout.decode('utf-8')

        logger.debug(command)
        logger.debug(data)
        text_view.get_buffer().set_text(data, -1)