#! /bin/bash
#################################################################################
#     File Name           :     media_converter.sh
#     Created By          :     jguer
#     Creation Date       :     [2016-06-15 20:31]
#     Last Modified       :     [2016-08-17 20:54]
#     Description         :      Jguer's media defaults for conversion
#################################################################################

readonly WORK_DIR="$(dirname "$(readlink -f "$0")")"
readonly OUTPUT_FOLDER=$(date +%Y-%m-%d-%H)

# Usage Function
function usage() {
cat <<_EOT_
Usage:
  $0 -m mediatype -i extension [-d target_directory]
Description:
  Converts files to more convenient format
Options:
  -m    audio|video|pic-lossy|pic-loss
  -i    input extension
  -d    target directory
  -h    display help
_EOT_
exit 1
}

function validate_filetype() {
  local _input=$1
  local _message=$2

  count=$(find ./*."$_input" 2>/dev/null | wc -l)
  if [ "$count" = 0 ]; then
    echo "$_message" 1>&2
    exit 1
  fi
}

function validate_folder() {
  local _foldername=$1
  local _message=$2

  if [ ! -d "$_foldername" ]; then
    echo "$_message" 1>&2
    exit 1
  fi
  return 0
}


# Main
## check options and arguments
if [ $# = 0 ]; then
  usage
  exit 1
fi

if [ "$OPTIND" = 1 ]; then
  while getopts m:i:d:h OPT
  do
    case $OPT in
      m)
        readonly MEDIA=$OPTARG
        ;;
      i)
        readonly INPUT=$OPTARG
        ;;
      d)
        readonly FOLDERNAME=$OPTARG
        validate_folder "$FOLDERNAME" "No such folder: '${FOLDERNAME}'"
        ;;
      h)
        usage
        ;;
      \?)
        echo "Try to enter the h option" 1>&2
        ;;
    esac
  done
else
  echo "No installed getopts-command" 1>&2
  exit 1
fi

shift $((OPTIND - 1))

if [[ -z $MEDIA || -z $INPUT ]]; then
  echo "No specify argument(s) of -m option or -i option" 1>&2
  exit 1
fi

## main
if [ ! -z "$FOLDERNAME" ]; then
  cd "$FOLDERNAME" || exit
fi

validate_filetype "$INPUT" "No files of selected extension"

if [ ! -d "$OUTPUT_FOLDER" ]; then
  mkdir "$OUTPUT_FOLDER"
fi

i=0
echo -ne 'Progress '"$i"/"$count"' \r'
for FILE in *."$INPUT"; do
  case "$MEDIA" in
    audio)
      output="m4a"
      ffmpeg -loglevel panic -i "$FILE" -c:a aac -q:a 2 -vn "${OUTPUT_FOLDER}/${FILE/%"$INPUT"/m4a}";
      ;;
    video)
      output="mkv"
      subtitle=${FILE/%"$INPUT"/srt}
      if [ -e "$subtitle" ]; then
        ffmpeg -hide_banner -loglevel panic -i "$FILE" -f srt -i "$subtitle" -c:v libx265 -preset medium -x265-params crf=26 -c:a aac -strict experimental -b:a 128k -metadata:s:s:0 language=en "${OUTPUT_FOLDER}/${FILE/%"$INPUT"/mkv}"
      else
        ffmpeg -hide_banner -loglevel panic -i "$FILE" -c:v libx265 -preset medium -x265-params crf=28 -c:a aac -strict experimental -b:a 128k "${OUTPUT_FOLDER}/${FILE/%"$INPUT"/mkv}"
      fi
      ;;
    pic-lossy)
      output="webp"
      cwebp -quiet -q 90 "$FILE" -o "${OUTPUT_FOLDER}/${FILE/%"$INPUT"/$output}"
      ;;
    pic-loss)
      output="webp"
      cwebp -quiet -lossless "$FILE" -o "${OUTPUT_FOLDER}/${FILE/%"$INPUT"/$output}"
      ;;
    *)
      echo "Invalid Media Mode"
      ;;
  esac

  ((i++))
  echo -ne 'Progress '"$i"/"$count"' \r'
  if [ "$i" = "$count" ]; then
    echo -ne '\n'
  fi
done