import os
import sys
import traceback
import subprocess

def clearScreen():
	os.system('cls' if os.name == 'nt' else 'clear')

def convertFilesInImport():
	for filename in os.listdir('input'):
		print(f"{getInputPath()}{filename}")
		frame_rate_string = getFrameRate(f"{getInputPath()}{filename}")
		width = int(getWidth(f"{getInputPath()}{filename}"))
		height = int(getHeight(f"{getInputPath()}{filename}"))
		frame_rate = eval(frame_rate_string)
		print(f"Frame rate is: {frame_rate}")
		print(f"Width is: {width}")
		print(f"Height is: {height}")
		if width > height:
			bitrate = getRecommendedBitrateSetting(width,frame_rate)
		else:
			bitrate = getRecommendedBitrateSetting(height,frame_rate)
		print(f"Recommended bitrate: {bitrate}")
		current_bitrate = int(getBitrate(f"{getInputPath()}{filename}"))
		if current_bitrate < bitrate:
			print(f"Current bitrate of {current_bitrate} is less than recommended. Using {current_bitrate}")

		print("Converting now...")
		#os.path.splitext(filename)[0] gets ride of file extension 
		#yadiff is for deinterlace

		#Windows and Linux have different nulls. Windows null and Linux /dev/null
		FNULL = open(os.devnull, 'w')
		ffmpegcmd_nvidia = getFfmpegExe() + " -i " + getInputPath() + filename + " -vf yadif -b " + str(bitrate) + " -minrate " + str(bitrate) + " -maxrate " + str(bitrate) + " -bufsize " + str(bitrate) + " -vcodec h264_nvenc " + getAudioSetting() + " -y " + getOutputPath() + os.path.splitext(filename)[0] + ".mp4"
		
		# shell=True is not safe but needs used because I do not comma separate the commmand like:
		# ["ffmpeg.exe", "-i", "etc"]
		process = subprocess.Popen(ffmpegcmd_nvidia, stdout=FNULL, stderr=FNULL, shell=True)
		process.communicate()[0]
		if process.returncode != 0:
			print("Using Nvidia gpu failed... Trying Intel.")
			ffmpegcmd_intel = ffmpegcmd_nvidia.replace("h264_nvenc", "h264_qsv")
		else:
			continue
		process = subprocess.Popen(ffmpegcmd_intel, stdout=FNULL, stderr=FNULL, shell=True)
		process.communicate()[0]
		if process.returncode != 0:
			print("Using Intel gpu failed... Trying CPU.")
			ffmpegcmd = ffmpegcmd_nvidia.replace("h264_qsv", "h264")
		else:
			continue
		process = subprocess.Popen(ffmpegcmd, stdout=FNULL, stderr=FNULL, shell=True)
		process.communicate()[0]
		if process.returncode != 0:
			raise Exception('There was an error running ffmpeg.')

def getFrameRate(file):
	ffprobe_args = "-v 0 -of csv=p=0 -select_streams v:0 -show_entries stream=r_frame_rate"
	ffprobe_exe = getFfprobeExe()
	ffprobe_command = f"{ffprobe_exe} {ffprobe_args} {file}"
	# popen then .read() allows setting stdout to a variable
	return os.popen(ffprobe_command).read()

def getWidth(file):
	ffprobe_args = "-v 0 -of csv=p=0 -select_streams v:0 -show_entries stream=width"
	ffprobe_exe = getFfprobeExe()
	ffprobe_command = f"{ffprobe_exe} {ffprobe_args} {file}"
	# popen then .read() allows setting stdout to a variable
	return os.popen(ffprobe_command).read()

def getHeight(file):
	ffprobe_args = "-v 0 -of csv=p=0 -select_streams v:0 -show_entries stream=height"
	ffprobe_exe = getFfprobeExe()
	ffprobe_command = f"{ffprobe_exe} {ffprobe_args} {file}"
	# popen then .read() allows setting stdout to a variable
	return os.popen(ffprobe_command).read()

def getBitrate(file):
	ffprobe_args = "-v 0 -of csv=p=0 -select_streams v:0 -show_entries stream=bit_rate"
	ffprobe_exe = getFfprobeExe()
	ffprobe_command = f"{ffprobe_exe} {ffprobe_args} {file}"
	# popen then .read() allows setting stdout to a variable
	return os.popen(ffprobe_command).read()

def getFfmpegPath():
	if(sys.platform == "win32"):
		return "ffmpeg\\windows"
	elif(sys.platform == "darwin"):
		return "ffmpeg/osx"
	else:
		# Linux sys.platform returns 'linux'
		returnErrorAndExit("Your os is not supported. Try using Windows or OSX")

def getFfmpegExe():
	path = getFfmpegPath()
	if(sys.platform == "win32"):
		return f"{path}\\ffmpeg.exe"
	else:
		return f"{path}/ffmpeg"

def getFfprobeExe():
	path = getFfmpegPath()
	if(sys.platform == "win32"):
		return f"{path}\\ffprobe.exe"
	else:
		return f"{path}/ffprobe"

def getOutputPath():
	if(sys.platform == "win32"):
		return "output\\"
	else:
		return "output/"

def getInputPath():
	if(sys.platform == "win32"):
		return "input\\"
	else:
		return "input/"

# def askForResolution():
# 	inputresolution = "0"
# 	while(inputresolution != "1" and inputresolution != "2" and inputresolution != "3" and inputresolution != "4" and inputresolution != "5" and inputresolution != "6" and inputresolution != "7" and inputresolution != "8"):
# 		clearScreen()
# 		print("Tell me about your source video.")
# 		print("1. 4k at a slow frame rate (24, 25, 30)")
# 		print("2. 1080p at a slow frame rate (24, 25, 30)")
# 		print("3. 720p at a slow frame rate (24, 25, 30)")
# 		print("4. 480p at a slow frame rate (24, 25, 30)")
# 		print("5. 4k at a fast frame rate (48, 50, 60)")
# 		print("6. 1080p at a fast frame rate (48, 50, 60)")
# 		print("7. 720p at a fast frame rate (48, 50, 60)")
# 		print("8. 480p at a fast frame rate (48, 50, 60)")
# 		inputresolution = input("Please enter a number from above: ")
# 	return inputresolution

def askForAudioOutput():
	audioOutput = "0"
	while(audioOutput != "1" and audioOutput != "2" and audioOutput != "3" and audioOutput != "4"):
		clearScreen()
		print("Tell me what you would like your audio to output as.")
		print("1. For no audio")
		print("2. For Mono audio")
		print("3. For Stereo audio")
		print("4. For 5.1 audio")
		audioOutput = input("Please enter a number from above: ")
	return audioOutput

def getRecommendedBitrateSetting(longest_side,frame_rate):
	# Bitrates recommended from YouTube: https://support.google.com/youtube/answer/1722171?hl=en
	if frame_rate <= 30:
		if longest_side > 1920:
			# 4k size
			# 40,000k bitrate
			return 40000000
		elif longest_side > 1280:
			# 1080p size
			# 8000k bitrate
			return 8000000
		elif longest_side > 852:
			# 720p size
			# 5000k bitrate
			return 5000000
		else:
			# 480p size
			# 2500k bitrate
			return 2500000
	else:
		if longest_side > 1920:
			# 4k size
			# 55,000k bitrate
			return 55000000
		elif longest_side > 1280:
			# 1080p size
			# 12,000k bitrate
			return 12000000
		elif longest_side > 852:
			# 720p size
			# 7500k bitrate
			return 7500000
		else:
			# 480p size
			# 4000k bitrate
			return 4000000

def getAudioSetting():
	if(audio == "1"):
		return " -an"
	elif(audio == "2"):
		return " -ab 128k"
	elif(audio == "3"):
		return " -ab 384k"
	elif(audio == "4"):
		return " -ab 512k"


def returnErrorAndExit(message):
	input(message)
	sys.exit(1)

#Run Program
try:
	# resolution = askForResolution()
	audio = askForAudioOutput()
	convertFilesInImport()
	input("Done. Press enter to exit.")
except Exception:
    print(traceback.print_exc())
    input("Press enter to exit.")
    sys.exit(1)