#! /usr/bin/env python3

import youtube_dl
import json
import ffmpeg
import subprocess
import glob
import sys
import argparse
import os

def generate_thumbnail(in_filename, out_filename, time, height):
    try:
        (
            ffmpeg
            .input(in_filename, ss=time)
            .filter('scale', -2, height)
            .output(out_filename, vframes=1)
            .overwrite_output()
            .run(capture_stdout=True, capture_stderr=True)
        )
    except ffmpeg.Error as e:
        print(e.stderr.decode(), file=sys.stderr)
        sys.exit(1)

# setting width and height from hardcoded defaults -> configured defaults -> clip
def getDimensions(config, clip):
	h = config['height'] if 'height' in config else 480 
	w = config['width'] if 'width' in config else -2
	if 'scale' in clip:
		h = clip['scale']['h'] if 'h' in clip['scale'] else h
		w = clip['scale']['w'] if 'w' in clip['scale'] else w

	return h, w


config = {
	'vcodec': "vp9",
	'acodec': "libopus",
	'height': 480,
	'quality': "best",
}


argParser = argparse.ArgumentParser()

jsonFileName = sys.argv[1]

clipDict = {}
with open(jsonFileName) as jf:
	clipDict = json.load(jf)

ydl_opts = {"outtmpl": "%(id)s"}

for clip in clipDict:
	# create the directories so ffmpeg doesn't complain
	try:
		outputDir = os.path.dirname(clip['target'])
		os.makedirs(outputDir)
	except:
		print(f"Couldn't create {outputDir}")

	infoDict = None
	with youtube_dl.YoutubeDL(ydl_opts) as ydl:
		infoDict = ydl.extract_info(clip['source'], download=False)
		ydl.download([clip['source']])
		
	if infoDict is not None:
		# @todo This is a very bad hack because the outtmpl options doesn't seem to be working if the file gets reencoded
		inputFilename = glob.glob(infoDict['id']+"*")[0]

		# generate preview image for the video
		if 'poster' in clip:
			generate_thumbnail(inputFilename, os.path.splitext(clip['target'])[0]+".jpg", clip['poster']['timeIndex'], h )

		kwArgs = {}
		if 'from' in clip:
			kwArgs['ss'] = clip['from']
		if 'to' in clip:
			kwArgs['to'] = clip['to']

		stream = ffmpeg.input( inputFilename, **kwArgs)

		video, audio = stream.video, stream.audio

		if 'crop' in clip:
			stream = ffmpeg.filter(stream, 
				"crop",
				x=clip['crop']['x'],
				y=clip['crop']['y'],
				w=clip['crop']['w'],
				h=clip['crop']['h']
			)

		h, w = getDimensions(config, clip)

		stream = ffmpeg.output(stream, 
			clip['target'], 
			vcodec=config['vcodec'], 
			**{
				# "an":None,
				"y":None, 
				"pass":"1", 
				# "b:v":"276k", "minrate":"138k", "maxrate":"400k", # x360
				"b:v":"512k", "minrate":"256k", "maxrate":"742k", # x480 LQ
				# "b:v":"750k", "minrate":"375k", "maxrate":"1088k", # x480 MQ
				"quality": config['quality'] if 'quality' in config else "best", 
			}
		)
		try:
			ffmpeg.run(stream)
		except:
			print(infoDict)


		if 'from' in clip and 'to' in clip:
			stream = ffmpeg.input(
				glob.glob(infoDict['id']+"*")[0], 
				ss=clip['from'], 
				to=clip['to'], 
			)
		else:
			stream = ffmpeg.input(
				glob.glob(infoDict['id']+"*")[0]
			)
		if 'crop' in clip:
			stream = ffmpeg.filter(stream, 
				"crop",
				x=clip['crop']['x'],
				y=clip['crop']['y'],
				w=clip['crop']['w'],
				h=clip['crop']['h']
			)

		h, w = getDimensions(config, clip)

		stream = ffmpeg.output(stream, audio, 
			clip['target'], 
			vcodec=config['vcodec'], 
			**{
				# "an":None,
				"y":None, 
				"pass":"2", 
				# "b:v":"276k", "minrate":"138k", "maxrate":"400k", # x360
				"b:v":"512k", "minrate":"256k", "maxrate":"742k", # x480 LQ
				# "b:v":"750k", "minrate":"375k", "maxrate":"1088k", # x480 MQ
				"quality": config['quality'] if 'quality' in config else "best", 
				"acodec": config['acodec'],
			}
		)
		try:
			ffmpeg.run(stream)
		except:
			print(infoDict)
		
		exit(-1)