#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Name: FFMPEG Class
Author: K4YT3X
Date Created: Feb 24, 2018
Last Modified: March 9, 2019

Description: This class handles all FFMPEG related
operations.
"""
from avalon_framework import Avalon
import json
import subprocess


class Ffmpeg:
    """This class communicates with ffmpeg

    This class deals with ffmpeg. It handles extracitng
    frames, stripping audio, converting images into videos
    and inserting audio tracks to videos.
    """

    def __init__(self, ffmpeg_settings):
        self.ffmpeg_settings = ffmpeg_settings
        self._parse_settings()
    
    def _parse_settings(self):
        """ Parse ffmpeg settings
        """
        self.ffmpeg_path = self.ffmpeg_settings['ffmpeg_path']
        # Add a forward slash to directory if not present
        # otherwise there will be a format error
        if self.ffmpeg_path[-1] != '/' and self.ffmpeg_path[-1] != '\\':
            self.ffmpeg_path = '{}/'.format(self.ffmpeg_path)

        self.ffmpeg_binary = '\"{}ffmpeg.exe\"'.format(self.ffmpeg_path)
        self.ffmpeg_hwaccel = self.ffmpeg_settings['ffmpeg_hwaccel']
        self.extra_arguments = self.ffmpeg_settings['extra_arguments']

    def get_video_info(self, input_video):
        """ Gets input video information

        This method reads input video information
        using ffprobe in dictionary.

        Arguments:
            input_video {string} -- input video file path

        Returns:
            dictionary -- JSON text of input video information
        """
        execute = '\"{}ffprobe.exe\" -v quiet -print_format json -show_format -show_streams \"{}\"'.format(self.ffmpeg_path, input_video)
        Avalon.debug_info('Executing: {}'.format(execute))
        json_str = subprocess.check_output(execute)
        return json.loads(json_str.decode('utf-8'))

    def extract_frames(self, input_video, extracted_frames):
        """Extract every frame from original videos

        This method extracts every frame from videoin
        using ffmpeg

        Arguments:
            input_video {string} -- input video path
            extracted_frames {string} -- video output folder
        """
        execute = '{} -i \"{}\" \"{}\"\\extracted_%0d.png -y {}'.format(
            self.ffmpeg_binary, input_video, extracted_frames, ' '.join(self.extra_arguments))
        Avalon.debug_info('Executing: {}'.format(execute))
        subprocess.run(execute, shell=True, check=True)

    def convert_video(self, framerate, resolution, upscaled_frames):
        """Converts images into videos

        This method converts a set of images into a
        video.

        Arguments:
            framerate {float} -- target video framerate
            resolution {string} -- target video resolution
            upscaled_frames {string} -- source images folder
        """
        execute = '{} -r {} -f image2 -s {} -i \"{}\"\\extracted_%d.png -vcodec libx264 -crf 25 -pix_fmt yuv420p \"{}\"\\no_audio.mp4 -y {}'.format(
            self.ffmpeg_binary, framerate, resolution, upscaled_frames, upscaled_frames, ' '.join(self.extra_arguments))
        Avalon.debug_info('Executing: {}'.format(execute))
        subprocess.run(execute, shell=True, check=True)

    def migrate_audio_tracks_subtitles(self, input_video, output_video, upscaled_frames):
        """ Migrates audio tracks and subtitles from input video to output video

        Arguments:
            input_video {string} -- input video file path
            output_video {string} -- output video file path
            upscaled_frames {string} -- directory containing upscaled frames
        """
        execute = '{} -i \"{}\"\\no_audio.mp4 -i \"{}\" -map 0:v:0? -map 1? -c copy -map -1:v? \"{}\" -y {}'.format(
            self.ffmpeg_binary, upscaled_frames, input_video, output_video, ' '.join(self.extra_arguments))
        # execute = '{} -i \"{}\"\\no_audio.mp4 -i \"{}\" -c:a copy -c:v copy -c:s copy -map 0:v? -map 1:a? -map 1:s? \"{}\" -y {}'.format(
            # self.ffmpeg_binary, upscaled_frames, input_video, output_video, ' '.join(self.ffmpeg_arguments))
        Avalon.debug_info('Executing: {}'.format(execute))
        subprocess.run(execute, shell=True, check=True)