#!/bin/bash

ffmpeg="$(command -v ffmpeg)"
dest="/home/zefie/downloads/manual"
ext=mkv # output ext
fps=24 # video fps for tuning
olddir="old" # where source files go when we are done (relative to $workdir)
outdir="zefie" # where new files go when we are done (relative to $workdir)
baddir="bad" # where files with decode errors end up (relative)
ffmpeg_avg_br=5M
ffmpeg_buf=8M
ffmpeg_max_br=12M
ffmpeg_aud_opts=(-b:a 320k)
ffmpeg_mov_avg_br=10M
ffmpeg_mov_buf=10M
ffmpeg_mov_max_br=20M
ffmpeg_mov_aud_opts=("${ffmpeg_aud_opts[@]}")

vcodec=hevc
acodec=aac
ffmpeg_threads=4
preset=hq
twopass=true
errchk=1
delete=1
use_nvidia=1 # comment/unset to disable
use_nvidia_encoder=1 # ignored if use_nvidia unset
use_nvidia_decoder=1 # ignored if use_nvidia unset

REPLACE=( \
	"H.264|HEVC" \
	"x264|HEVC" \
	"NTb|zefie" \
	"QOQ|zefie" \
	"DDP5.1|AAC5.1" \
	"DD+2.0|AAC2.0" \
)


# end config


ffmpeg_opts=()
processed_count=0
FILES=()

if [ "${1}" == "movie" ]; then
	echo " [!!!] Executing in movie mode, using higher bitrates."
	ffmpeg_avg_br="${ffmpeg_mov_avg_br}";
	ffmpeg_buf="${ffmpeg_mov_buf}";
	ffmpeg_max_br="${ffmpeg_mov_max_br}";
	ffmpeg_aud_opts=("${ffmpeg_mov_aud_opts[@]}")
	shift;
fi

if [ "${1}" == "noerr" ]; then
	echo " [!!!] Executing in noerr mode, ffmpeg will NOT fail on minor errors!"
	errchk=
	shift;
fi

if [ "${1}" == "nomove" ]; then
	echo " [!!!] Executing in nomove mode, will not move failed files to ${baddir} !"
	nomove=1
	shift;
fi

if [ "${1}" == "nodel" ]; then
	echo " [!!!] Executing in old mode, will not delete files, will place them in ${olddir}"
	delete=
	shift;
fi

if [ -z "${1}" ] || [ ! -d "${1}" ]; then
	if [ ! -z "${1}" ] && [ -f "${1}" ]; then
		workdir="$(realpath "$(dirname "${1}")")"
		singlefile="$(realpath "${1}")"
		echo " [***] Single File Mode: ${singlefile} ..."
	else
		workdir="$(realpath "${PWD}")"
	fi
else
	workdir="$(realpath "${1}")"
fi

echo " [***] Working in ${workdir} ..."

if [ -z "${delete}" ]; then
	olddir="${workdir}/${olddir}";
fi
outdir="${workdir}/${outdir}"
baddir="${workdir}/${baddir}"


function detect_hw_encoder() {
	if [ -e "/dev/nvidia0" ] && [ ! -z "${use_nvidia}" ] && [ ! -z "${use_nvidia_encoder}" ]; then
		case "${vcodec}" in
				hevc)
					echo hevc_nvenc;
					;;
				h264)
					echo h264_nvenc;
					;;
				*)
					echo "${vcodec}";
					;;
		esac
	else
		case "${vcodec}" in
				hevc)
					echo libx265;
					;;
				h264)
					echo libx264;
					;;
				*)
					echo "${vcodec}";
					;;
		esac
	fi
}


function detect_hw_decoder() {
	local codec_data codec_res;
	codec_data="$(mediainfo --Inform="Video;%Format%" "${1}")"
	if [ -e "/dev/nvidia0" ] && [ ! -z "${use_nvidia}" ] && [ ! -z "${use_nvidia_decoder}" ]; then
		case "${codec_data}" in
					AVC)
						echo " [***] Using NVidia Accelerated H.264 Decoder" 1>&2
						codec_res=(-hwaccel cuvid -c:v h264_cuvid);
						;;
					HEVC)
						echo " [***] Using NVidia Accelerated HEVC Decoder" 1>&2
						codec_res=(-hwaccel cuvid -c:v henc_cuvid);
						;;
					MJPEG)
						echo " [***] Using NVidia Accelerated MJPEG Decoder" 1>&2
						codec_res=(-hwaccel cuvid -c:v mjpeg_cuvid);
						;;
					MPEG1)
						echo " [***] Using NVidia Accelerated MPEG1 Decoder" 1>&2
						codec_res=(-hwaccel cuvid -c:v mpeg1_cuvid);
						;;
					MPEG2)
						echo " [***] Using NVidia Accelerated MPEG2 Decoder" 1>&2
						codec_res=(-hwaccel cuvid -c:v mpeg2_cuvid);
						;;
					MPEG4)
						echo " [***] Using NVidia Accelerated MPEG4 Decoder" 1>&2
						codec_res=(-hwaccel cuvid -c:v mpeg4_cuvid);
						;;
					VC1)
						echo " [***] Using NVidia Accelerated VC1 Decoder" 1>&2
						codec_res=(-hwaccel cuvid -c:v vc1_cuvid);
						;;
					VP8)
						echo " [***] Using NVidia Accelerated VP8 Decoder" 1>&2
						codec_res=(-hwaccel cuvid -c:v vp8_cuvid);
						;;
					VP9)
						echo " [***] Using NVidia Accelerated VP9 Decoder" 1>&2
						codec_res=(-hwaccel cuvid -c:v vp9_cuvid);
						;;
					*)
						echo " [***] Using Software Video Decoder" 1>&2
						codec_res=();
						;;
		esac
	else
		echo " [***] Using Software Video Decoder" 1>&2
		codec_res=();
	fi
	echo "${codec_res[@]}"
}


function prepare_ffmpeg_opts() {
	local cuvid_dec ffmpeg_opts_in ffmpeg_opts_qual ffmpeg_opts_out codec ffmpeg_opts_audio_out ffmpeg_opts_in_generic;

	ffmpeg_opts_audio_out=(-c:a "${acodec}" "${ffmpeg_aud_opts[@]}")
	ffmpeg_opts_in_generic=(-y -loglevel warning -stats -threads "${ffmpeg_threads}")
	if [ ! -z "${errchk}" ]; then
		ffmpeg_opts_in_generic=("${ffmpeg_opts_in_generic[@]}" -xerror)
	fi


	codec=$(detect_hw_encoder);
	# shellcheck disable=SC2207
	cuvid_dec=($(detect_hw_decoder "${1}"));
	if [ "${codec}" = "hevc_nvenc" ]; then
		echo " [***] Using NVidia Accelerated HEVC Encoder" 1>&2
		ffmpeg_opts_in=("${ffmpeg_opts_in_generic[@]}" "${cuvid_dec[@]}")
		ffmpeg_opts_qual=(-preset "${preset}" -profile:v main -level:v 5.1 -2pass "${twopass}" -tier high -rc:v vbr_hq -b:v "${ffmpeg_avg_br}" -maxrate:v "${ffmpeg_max_br}" -bufsize:v "${ffmpeg_buf}" -g $((fps * 10)) -map 0 -movflags use_metadata_tags -movflags faststart)
		ffmpeg_opts_out=("${ffmpeg_opts_audio_out[@]}" -c:v "${codec}" "${ffmpeg_opts_qual[@]}" -f matroska)
	fi

	if [ "${codec}" = "libx265" ]; then
		echo " [***] Using Software x265 Encoder" 1>&2
		ffmpeg_opts_in=("${ffmpeg_opts_in_generic[@]}" "${cuvid_dec[@]}")
		ffmpeg_opts_qual=(-preset "${preset}" -tune grain -x265-params "'-no-scenecut=1:-2pass=${twopass}:-rc=vbr_hq:-rc-lookahead=${fps}:-surfaces=56'" -b:v "${ffmpeg_avg_br}" -maxrate:v "${ffmpeg_max_br}" -bufsize:v "${ffmpeg_buf}" -g $((fps * 10)) -map 0 -movflags use_metadata_tags -movflags faststart)
		ffmpeg_opts_out=("${ffmpeg_opts_audio_out[@]}" -c:v "${codec}" "${ffmpeg_opts_qual[@]}" -f matroska)
	fi
	ffmpeg_opts=("${ffmpeg_opts_in[@]}" -i "${1}" "${ffmpeg_opts_out[@]}" "${2}")
}

zcmd() {
	while [ ! -z "${1}" ]; do
		case "${1}" in
				silent)
					local SILENT=1;
					shift
					;;
				errchk)
					local ERRCHK=1;
					shift
					;;
				*)
					break;
					;;
		esac
	done

	if [ -z ${SILENT} ]; then
		echo " [***] Executing: ${*}"
	fi

	"${@}";
	local RES=$?
	if [ ${RES} != 0 ] && [ ! -z ${ERRCHK} ]; then
			echo "exiting with error ${RES}"
			exit "${RES}"
	fi
	return ${RES}
}


function process_file() {
	local fname res;
	if [ -z "${ext}" ]; then
		ext="$(echo "${f}" | rev | cut -d'.' -f1 | rev)"
	fi
	fname="$(basename "${f}" | rev | cut -d'.' -f2- | rev)"


	# renaming for output
	for rep in "${REPLACE[@]}"; do
		rep1=$(echo "${rep}" | cut -d'|' -f1)
		rep2=$(echo "${rep}" | cut -d'|' -f2)
		# shellcheck disable=SC2001
		fname="$(echo "${fname}" | sed "s|${rep1}|${rep2}|")"
		unset rep1 rep2;
	done

	if [ ! -d "${outdir}" ]; then
		zcmd errchk mkdir "${outdir}"
	fi

    # shellcheck disable=SC2207
	prepare_ffmpeg_opts "${1}" "${outdir}/${fname}.${ext}"
	zcmd "${ffmpeg}" "${ffmpeg_opts[@]}"
	res=$?
	if [ ${res} -eq 0 ] && [ -f "${outdir}/${fname}.${ext}" ]; then
		if [ -z "${delete}" ]; then
			if [ ! -d "${olddir}" ]; then
				zcmd errchk mkdir "${olddir}"
			fi
			zcmd errchk mv -v "${f}" "${olddir}/$(basename "${f}")"
		else
			zcmd errchk rm -v "${f}"
		fi
		if [ ! -z "${dest}" ] && [ ! -z "${errchk}" ]; then
			# move to dest, if defined, and if not running in noerr mode
			mv -v "${outdir}/${fname}.${ext}" "$(realpath "${dest}")/${fname}.${ext}"
		fi
    else
		if [ "${res}" -ne 255 ]; then
			echo " [!!!] errors while encoding ${f}!"
			if [ -z "${nomove}" ]; then
				if [ ! -d "${baddir}" ]; then
					zcmd errchk mkdir "${baddir}"
				fi
				echo "      Moving ${f} to ${baddir} ..."
				zcmd silent errchk mv "${f}" "${baddir}/$(basename "${f}")"
			fi
			echo "      Removing incomplete encoding at ${outdir}/${fname}.${ext} ..."
			zcmd silent rm -f "${outdir}/${fname}.${ext}"
		else
			echo "exiting with error ${res}"
			exit ${res}
		fi
	fi
	processed_count=$((processed_count+1))
}


if [ -z "${singlefile}" ]; then
	while IFS= read -r -d '' file; do
		if [ -f "${file}" ]; then
			if [ "$(echo "${file}" | grep 'zefie\.' -c)" -eq 0 ]; then
				FILES=("${FILES[@]}" "${file}")
			fi
		fi
	done < <(find "${workdir}" -maxdepth 1 -regextype posix-extended -regex '.*\.(mp4|mkv)' -print0);
else
	FILES=("${singlefile}")
fi

if [ "${#FILES[@]}" -gt 0 ]; then
	if [ -z "${singlefile}" ]; then
		# shellcheck disable=SC2207
		IFS=$'\n' sorted=($(sort <<<"${FILES[*]}")); unset IFS;
		FILES=("${sorted[@]}")
		unset sorted;
		echo -n " [***] Found ${#FILES[@]} file"
		if [ "${#FILES[@]}" -ne 1 ]; then
			echo -n "s";
		fi
		echo " ... processing now."
	fi

	for f in "${FILES[@]}"; do
			echo " [***] Processing ${f} (file $((processed_count+1)) of ${#FILES[@]}, $((${#FILES[@]}-processed_count-1)) remaining) ..."
			process_file "${f}"
	done
else
	echo " [!!!] Did not find any files :("
	exit 1
fi