"""Load and execute ArContext configuration."""

"""
This program is free software: you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation, either version 3 of the License, or (at your option) any later
version.
This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with
this program. If not, see <https://www.gnu.org/licenses/>.
"""

__author__ = "Théo de la Hogue"
__credits__ = []
__copyright__ = "Copyright 2023, Ecole Nationale de l'Aviation Civile (ENAC)"
__license__ = "GPLv3"

import argparse
import logging
import json
import contextlib
import time
import os
import stat

from . import load
from .ArFeatures import ArCamera, ArContext, PostProcessingContext, LiveProcessingContext
from .utils.UtilsFeatures import print_progress_bar

import cv2

# Manage arguments
parser = argparse.ArgumentParser(description=__doc__.split('-')[0])
parser.add_argument('context_file', metavar='CONTEXT_FILE', type=str, help='JSON context filepath')
parser.add_argument('-v', '--verbose', action='store_true', default=False, help='enable verbose mode to print information in console')
parser.add_argument('-p', '--pipe_path', metavar='PIPE_PATH', type=str, default=None, help='enable pipe communication to execute external commands')
parser.add_argument('-x', '--display', metavar='DISPLAY', nargs="+", type=int, default=[1920, 1080], help='adapt windows to display dimension')
parser.add_argument('--no-window', action='store_true', default=False, help='disable window mode')

args = parser.parse_args()

# Manage logging
logging.basicConfig(format='%(levelname)s: %(message)s', level=logging.DEBUG if args.verbose else logging.INFO)

# Manage pipe communication
if args.pipe_path is not None:

	# Create FIFO
	if not os.path.exists(args.pipe_path):

		os.mkfifo(args.pipe_path)

	# Open the fifo in non-blocking mode or it will stalls until someone opens it for writting
	pipe_file = os.open(args.pipe_path, os.O_RDONLY | os.O_NONBLOCK)

	logging.info('%s pipe opened', args.pipe_path)

def display(name, image, factor):
	"""Adapt image to display dimension."""

	display_size = tuple(args.display)
	height, width, _ = image.shape
	image_ratio = width/height

	new_image_size = (int(display_size[1] * factor * image_ratio), int(display_size[1] * factor))

	cv2.imshow(name, cv2.resize(image, dsize=new_image_size, interpolation=cv2.INTER_LINEAR))

# Load context from JSON file
with load(args.context_file) as context:

	# Loaded object must be a subclass of ArContext
	if not issubclass(type(context), ArContext):

		raise TypeError('Loaded object is not a subclass of ArContext')

	if args.verbose:

		print(context)

	if not args.no_window:

		# Create a window to display context
		cv2.namedWindow(context.name, cv2.WINDOW_AUTOSIZE)

	# Assess processing time
	start_time = time.time()

	# Waiting for 'ctrl+C' interruption
	with contextlib.suppress(KeyboardInterrupt), os.fdopen(pipe_file) if args.pipe_path is not None else contextlib.nullcontext() as pipe:

		# Visualization loop
		while context.is_running():

			# Read message from pipe if required
			if args.pipe_path is not None:

				try:

					message = pipe.read().rstrip('\n')

					if message:

						logging.info('%s pipe received: %s', args.pipe_path, message)

						exec(message)

				except Exception as e:

					logging.error('%s', e)

			# Window mode on
			if not args.no_window:

				# Display context
				display(context.name, context.image(), 0.75)

				# Head-mounted eye tracker case: display environment frames image
				if issubclass(type(context.pipeline), ArCamera):

					for scene_frame in context.pipeline.scene_frames():

						display(scene_frame.name, scene_frame.image(), 0.5)

				# Key interaction
				key_pressed = cv2.waitKey(40)

				# Esc: close window
				if key_pressed == 27:

					raise KeyboardInterrupt()

				# Space bar: pause/resume pipeline processing
				if key_pressed == 32:

					if context.is_paused():

						context.resume()

					else:

						context.pause()

				# Enter: start calibration
				if key_pressed == 13:

					if issubclass(type(context), LiveProcessingContext):

						context.calibrate()

			# Window mode off
			else:

				if issubclass(type(context), PostProcessingContext):

					prefix = f'Progression'
					suffix = f'| {int(context.progression*context.duration * 1e-3)}s in {int(time.time()-start_time)}s'

					look_time, look_freq = context.process_gaze_position_performance()
					suffix += f' | Look {look_time:.2f}ms at {look_freq}Hz'

					if issubclass(type(context.pipeline), ArCamera):

						watch_time, watch_freq = context.process_camera_image_performance()
						suffix += f' | Watch {int(watch_time)}ms at {watch_freq}Hz'

					# Clear old longer print
					suffix += '   '

					print_progress_bar(context.progression, 1., prefix = prefix, suffix = suffix, length = 50)

				# Wait one second
				time.sleep(1)

	# Stop frame display
	cv2.destroyAllWindows()

	# Manage pipe communication
	if args.pipe_path is not None:

		# Remove pipe
		if os.path.exists(args.pipe_path):

			os.remove(args.pipe_path)

			logging.info('%s pipe closed', args.pipe_path)