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

import json
import subprocess
import logging


def get_infos(file):
    '''
    Cette fonction extrait les informations du film à l'aide de ffprobe et les stocke
    dans un dictionnaire pour une utilisation ultérieure.

    -> http://ffmpeg.org/ffprobe.html
    '''
    v_infos = {
            'height': None,
            'width': None,
            'color_primaries': None,
            'color_space': None,
            'color_transfer': None,
            'display_aspect_ratio': None
            }
    a_infos = {}
    v_infos_cmd = f"ffprobe -v quiet -print_format json -show_format -show_streams -select_streams v {file}"
    v_infos_raw = subprocess.getoutput(v_infos_cmd)
    a_infos_cmd = f"ffprobe -v quiet -print_format json -show_format -show_streams -select_streams a {file}"
    a_infos_raw = subprocess.getoutput(a_infos_cmd)
    full_v_infos = json.loads(v_infos_raw)
    full_a_infos = json.loads(a_infos_raw)
    v_stream = full_v_infos['streams'][0]
    for prop in v_infos.keys():
        try:
            v_infos.update({prop: v_stream[prop]})
        except KeyError:
            pass
    a_infos = []
    for a_stream in full_a_infos['streams']:
        a_stream_infos = {
                'index': a_stream['index'],
                'channels': a_stream['channels']}
        a_infos.append(a_stream_infos)
    duration = subprocess.getoutput(f"ffprobe -v quiet -print_format json -show_format {file}")
    duration = json.loads(duration)
    duration = float(duration['format']['duration'])
    infos = {'duration': duration, 'video': v_infos, 'audio': a_infos}
    logging.debug("Informations du film : \n" + json.dumps(infos, indent=True))
    return infos


def is_interlaced(file, infos):
    '''
    Cette fonction detecte si la vidéo est entrelacée.
    -> https://fr.wikipedia.org/wiki/Entrelacement_(vid%C3%A9o)
    '''
    duration_tier = int(infos['duration'] / 3)
    command = f"ffmpeg -loglevel info -ss {duration_tier} -t {duration_tier} -i {file} -an -filter:v idet -f null -y /dev/null"
    result = subprocess.getoutput(command)
    for line in result.splitlines():
        if "Multi" in line:
            TFF = int(line.split('TFF:')[1].split()[0])
            BFF = int(line.split('BFF:')[1].split()[0])
            Progressive = int(line.split('Progressive:')[1].split()[0])
    try:
        pct = ((TFF + BFF) / (TFF + BFF + Progressive)) * 100
        pct = round(pct)
    except ZeroDivisionError:
        pct = 100
    if pct > 10:
        logging.debug("Vidéo entrelacée à {pct}%")
        return True
    else:
        logging.debug("Vidéo non entrelacée")
        return False


def cropping(file, infos):
    '''
    Cette fonction detecte les bandes inutiles de la vidéo
    '''
    duration_tier = int(infos['duration'] / 3)
    command = f"ffmpeg -loglevel info -i {file} -ss {duration_tier} -t {duration_tier} -an -f null -vf cropdetect -y /dev/null"
    cropsize = subprocess.getoutput(command).splitlines()[-3].split()[-1]
    logging.debug(f"Paramètre de découpe : {cropsize}")
    return cropsize


def volume_audio(file, infos):
    '''
    Cette fonction ajuste le volume vers 0dB
    '''
    volumes = {}
    for piste_audio in infos['audio']:
        piste = piste_audio['index']
        command = f"ffmpeg -loglevel info -i {file} -map 0:{piste} -af volumedetect -f null -y /dev/null"
        volumedetect = subprocess.getoutput(command)
        for line in volumedetect.splitlines():
            if "max_volume" in line:
                volume = line.split()[-2]
                volume = f"{str(-float(volume))}dB"
        logging.debug(f"Ajustement du volume de la piste {piste} : {volume}")
        volumes.update({piste: volume})
    return volumes


if __name__ == '__main__':
    import argparse
    parser = argparse.ArgumentParser()
    parser.add_argument("f_input")
    parser.add_argument("-d", "--debug", dest='debug', action='store_true')
    args = parser.parse_args()
    if args.debug:
        logging.basicConfig(format='[%(asctime)s]\n%(message)s', level=logging.DEBUG, datefmt='%d/%m/%Y %H:%M:%S')
    else:
        logging.basicConfig(format='[%(asctime)s]\n%(message)s', level=logging.INFO, datefmt='%d/%m/%Y %H:%M:%S')
    infos = get_infos(args.f_input)
    interlaced = is_interlaced(args.f_input, infos)
    cropsize = cropping(args.f_input, infos)
    volumes = volume_audio(args.f_input, infos)