#!/bin/bash

# set shopt-options used by this shell-script
# Note, 0 (true) from shopt -q is "false" in a math context.
shopt -q globstar; globstar_set=$?
((globstar_set)) && shopt -s globstar
shopt -q extglob; extglob_set=$?
((extglob_set)) && shopt -s extglob

# return default shopt-options
function finish {
        ((globstar_set)) && shopt -u globstar
        ((extglob_set)) && shopt -u extglob
}
trap finish EXIT

print_help() {
  printf "Help: not implemented yet"
}

while getopts 'e:dh' flag; do
        case "${flag}" in
                e) extension+=("$OPTARG");;
                d) delete=true;;
                h) print_help
                exit 0;;
                *) exit 1 ;;
        esac
done

# Print available encoders
readarray -t encoders <<<$(ffmpeg -encoders -hide_banner|grep vp9)
echo "In FFMPEG verfügbare Encoder:"
for i in "${!encoders[@]}"; do
	echo "$i: ${encoders[i]}"
	#encoders[i]=$(echo ${encoders[0]} | awk '{print $2}')
done

# Choose an encoder
while :; do
	read -r -p "Choose an encoder [0]: " encoder
	[[ $encoder =~ ^[0-9]+$ ]] || { echo "Enter a valid number"; continue; }
	if ((encoder >= 0 && encoder < ${#encoders[@]})); then
		encoder=$(echo "${encoders[$encoder]}" | awk '{print $2}')
		break
	else
		echo "Not a valid encoder, try again"
	fi
done

# Choose an GPU, if encoder is GPU accelerated
# ls /sys/class/drm/renderD129/device/consumer*/consumer/ | grep supp
# lspci | grep ' VGA ' | cut -d" " -f 1 | xargs -i lspci -v -s {}
gpu="/dev/dri/renderD129"

# encoder-specific settings

# write array into string
extension="${extension[*]}"
# change separator
extension=${extension// /|}

for file in **/*.@($extension); do
	if [[ ${file: -3} == "mkv" ]]; then 
		file_out="${file%.*}2.mkv"
	else file_out="${file%.*}.mkv"; fi

	#just for testing. This will be removed in a future release
	echo "$encoder"

	#VP9_vaapi
	#there are problems with the -global_quality:v/-q:v settings only being able to make quality worse. Help is appreciated
	#not enough tested. So it is still experimental
	if [[ $encoder == "vp9_vaapi" ]]; then
		ffmpeg -hide_banner -hwaccel vaapi -vaapi_device $gpu -i "$file" -map 0 -c copy -c:v vp9_vaapi -rc_mode CQP -bf 1 -bsf:v vp9_raw_reorder,vp9_superframe -vf 'hwupload' "$file_out" &&
		if [[ "$delete" = true ]]; then rm "$file"; fi
	fi

	#VP9_qsv
	#was not able to test it. So it is still experimental
	if [[ $encoder == "vp9_qsv" ]]; then
		ffmpeg -hide_banner -hwaccel qsv -qsv_device $gpu -i "$file" -c:v vp9_qsv -vf 'hwupload' "${file%.*}.mkv" &&
		if [[ "$delete" = true ]]; then rm "$file"; fi
	fi

	#libvpx-vp9
	#...
done