#!/usr/bin/env python3
import ffmpeg
import sys
from more_itertools import chunked

ins = sys.argv[1:-1]
out = sys.argv[-1]

# pure grid
#subs = [ffmpeg.input(f).video.filter('subtitles', filename=f).filter('scale',384,216) for f in ins]
#hstacks = [ffmpeg.filter(chunk, 'hstack', inputs=5) for chunk in chunked(subs, 5)]
#vstack = ffmpeg.filter(hstacks, 'vstack', inputs=len(hstacks))
#audio = ffmpeg.filter([ffmpeg.input(f).audio for f in ins], 'amix', inputs=len(ins))

columns = 3
horiz = 1920 / columns
vert = 1080 / columns
subs = [ffmpeg.input(f).video.filter('subtitles', filename=f).filter('scale',horiz,vert) for f in ins]
hstacks = [ffmpeg.filter(chunk, 'hstack', inputs=columns) for chunk in chunked(subs, columns)]
vstack = ffmpeg.filter(hstacks, 'vstack', inputs=len(hstacks))
audio = [ffmpeg.input(f).audio for f in ins]

opts = {
        'c:v': 'libx264',
        'preset': 'veryfast',
        'tune': 'animation',
        'movflags': 'faststart',
        'crf': '28',
        'c:a': 'aac',
        'b:a': '160k',
        'ac': '1',
        #'t': '60'
        }
ffmpeg.output(vstack, *audio, out, **opts).run()