#!/bin/bash

IFS="
"

usage() {
	echo "Usage:"
	echo "  $0 [-n #] <dir>"
	echo ""
	echo "  -n <N>     Quality 1..10 (default: 3.0"
	echo ""
	echo "Example:"
	echo "  ~/bin/prepare_audio.sh ; rm ./*.(ogg|mp3) ; mv smalleroggs/* . ; rm -r smalleroggs"
}

QUALITY="3.0"

while getopts n:h opt ; do
	case "$opt" in
		-)   break ;;
		[hH]) usage ; exit ;;
		n)    QUALITY=$OPTARG ;;
	esac
done
shift $((OPTIND - 1))

DIR="$(pwd)"
if [ -d "$1" ] ; then
	DIR="$1"
fi

mkdir -p "$DIR/smalleroggs"
TMP="$(mktemp)"

find "$DIR" -maxdepth 1 -iname '*.ogg' -o -iname '*.mp3' -o -iname '*.flac'|while read -r FILE ; do
	NAME=$( basename "$FILE" )
	echo "Processing \"$NAME\"..."
	case $FILE in 
		*\.ogg)
			oggdec "$FILE" -o "$TMP"
			oggenc -q "$QUALITY" -o "$DIR/smalleroggs/$NAME" "$TMP"
			if [ $? -eq 0 ] ; then
				vorbiscomment -l "$FILE" | vorbiscomment -w -c /dev/stdin "$DIR/smalleroggs/$NAME"
			fi
			;;
		*\.mp3)
			mp32ogg --quality "$QUALITY" "$FILE"
			mv "${FILE/.mp3/.ogg}" "$DIR/smalleroggs"
			;;
		*\.flac)
			oggenc -q "$QUALITY" -o "$DIR/smalleroggs/${NAME/.flac/.ogg}" "$FILE"
			;;
		*)
			echo "don’t know how to handle '$FILE'..."
			;;
	esac
done

rm "$TMP"