#!/bin/.sh
# vim: set sw=4 ts=4 sts=4 et :

clean() {
    echo "$1" | sed \
        -e "s/’/'/g" \
        -e 's/?//g' \
        -e 's@ / @ _ @g' \
        -e 's@/@-@g' \
        -e 's/: / - /g' \
        -e 's/:/-/g' \
        -e 's/\.\+$//'
}

convert() {
    unset src dst cover
    src="${1}"
    dst="${2}"

    cover="${src%/*}/folder.jpg"

    mkdir -p "${dst%/*}"
    echo "${dst}" >> /tmp/modified.txt
    printf 'Converting %s to %s ...\n' "${src##*/}" "${dst##*/}"
    ffmpeg \
        -loglevel warning \
        -i "${src}" \
        -vn \
        -ar 44100 \
        -ac 2 \
        -b:a 256k \
        "${dst}" \
        < /dev/null \
        || return $?
    if [ -f "${cover}" ]; then
        printf 'Embedding %s in %s ...\n' "${cover##*/}" "${dst##*/}"
        ffmpeg \
            -loglevel warning \
            -i "${dst}" \
            -i "${cover}" \
            -c copy \
            -map 0:0 \
            -map 1:0 \
            -id3v2_version 3 \
            -metadata:s:v title='Album Cover' \
            -metadata:s:v comment='Cover (Front)' \
            "${dst%.mp3}.new.mp3" \
            < /dev/null \
            || return $?
        mv "${dst%.mp3}.new.mp3" "${dst}"
    fi
}

rm -f /tmp/modified.txt
cd ~/.homeshare
find Music -name '*.flac' -printf '%T@%p\n' \
    | sed -E 's/^([0-9]+)(\.[0-9]+)(.*)/\1\3/' \
    | sort -t '' -k2 \
    > /tmp/music.txt
while IFS='' read timestamp filename; do
    album=$(metaflac --show-tag=album "${filename}" | sed 's/^album=//')
    albumartist=$(metaflac --show-tag=albumartist "${filename}" \
        | sed 's/^albumartist=//' \
        | head -n1)
    artist=$(metaflac --show-tag=artist "${filename}" \
        | sed 's/^artist=//' \
        | head -n1)
    discnumber=$(metaflac --show-tag=discnumber "${filename}" \
        | sed 's/^discnumber=//')
    disctotal=$(metaflac --show-tag=disctotal "${filename}" \
        | sed 's/^disctotal=//')
    tracknumber=$(metaflac --show-tag=tracknumber "${filename}" \
        | sed 's/^tracknumber=//')
    title=$(metaflac --show-tag=title "${filename}" | sed 's/^title=//')
    if [ -n "${disctotal}" ] || [ "${discnumber:-0}" -gt 0 ]; then
        newfilename=$(printf \
            '%s - %s Disc %d/%02d %s - %s.mp3' \
            "$(clean "${albumartist:-${artist}}")" \
            "$(clean "${album}")" \
            "${discnumber:-1}" \
            "${tracknumber:-0}" \
            "$(clean "${artist}")" \
            "$(clean "${title}")"
        )
    else
        newfilename=$(printf \
            '%s - %s/%02d %s - %s.mp3' \
            "$(clean "${albumartist:-${artist}}")" \
            "$(clean "${album}")" \
            "${tracknumber:-0}" \
            "$(clean "${artist}")" \
            "$(clean "${title}")"
        )
    fi
    if [ ! -f "TRUCKMUSIC/${newfilename}" ]; then
        convert "${filename}" "TRUCKMUSIC/${newfilename}"
    else
        newtimestamp=$(stat -c %Y "TRUCKMUSIC/${newfilename}")
        if [ "${timestamp}" -gt "${newtimestamp}" ]; then
            convert "${filename}" "TRUCKMUSIC/${newfilename}"
        fi
    fi
done < /tmp/music.txt