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

Description: This class handles all FFMPEG related
operations.

Version 1.1
"""

import os


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_path, outfile):
        self.ffmpeg_path = ffmpeg_path
        self.outfile = outfile

    def extract_frames(self, videoin, outpath):
        """Extract every frame from original videos

        This method extracts every frame from videoin
        using ffmpeg

        Arguments:
            videoin {string} -- input video path
            outpath {string} -- video output folder
        """
        os.system(
            "{} -i {} {}/extracted_%0d.png -y".format(self.ffmpeg_path, videoin, outpath))

    def extract_audio(self, videoin, outpath):
        """Strips audio tracks from videos

        This method strips audio tracks from videos
        into the output folder in aac format.

        Arguments:
            videoin {string} -- input video path
            outpath {string} -- video output folder
        """
        os.system(
            "{} -i {} -vn -acodec copy {}/output-audio.aac -y".format(self.ffmpeg_path, videoin, outpath))

    def to_vid(self, framerate, resolution, folder):
        """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
            folder {string} -- source images folder
        """
        os.system("{} -r {} -f image2 -s {} -i {}/extracted_%d.png -vcodec libx264 -crf 25 -pix_fmt yuv420p output.mp4 -y".format(
            self.ffmpeg_path, framerate, resolution, folder))

    def insert_audio_track(self, videoin, outpath):
        """Insert audio into video

        Inserts the AAC audio track stripped from
        the original video into final video.

        Arguments:
            videoin {string} -- input video path
            outpath {string} -- video output folder
        """
        os.system("{} -i {} -i {}/output-audio.aac -codec copy -shortest {} -y".format(
            self.ffmpeg_path, videoin, outpath, self.outfile))