wav_to_flac.sh

#!/bin/sh

if [ -z "$1" ]; then
    echo "Usage: $(basename "$0") input.wav [input.wav] [...]"
    exit 0
fi

red () {
    echo "\x1B[91m$1\x1B[0m"
}

blue () {
    echo "\x1B[96m$1\x1B[0m"
}

strip_extension () {
    echo "$1" | rev | cut -f 2- -d '.' | rev
}

filesize () {
    FSIZE="$(wc -c "$1" | awk '{print $1}')"
    REDUCTION=

    if [ "$2" ]; then
        REDUCTION=", $(echo "scale=2;(1 - ${FSIZE}/$2) * 100" | bc)% reduction"
    fi

    KB=1024
    MB=1048576
    GB=1073741824
    TB=1099511627776
    PB=1125899906842624

    [ "$FSIZE" -lt $KB ] 2>/dev/null && echo "$FSIZE bytes$REDUCTION" && return
    [ "$FSIZE" -lt $MB ] 2>/dev/null && echo "$FSIZE bytes [$(echo "scale=2;$FSIZE/$KB" | bc)KiB]$REDUCTION" && return
    [ "$FSIZE" -lt $GB ] 2>/dev/null && echo "$FSIZE bytes [$(echo "scale=2;$FSIZE/$MB" | bc)MiB]$REDUCTION" && return
    [ "$FSIZE" -lt $TB ] 2>/dev/null && echo "$FSIZE bytes [$(echo "scale=2;$FSIZE/$GB" | bc)GiB]$REDUCTION" && return
    [ "$FSIZE" -lt $PB ] 2>/dev/null && echo "$FSIZE bytes [$(echo "scale=2;$FSIZE/$TB" | bc)TiB]$REDUCTION" && return
}

current_wave_file=
current_flac_file=
clean_up_and_exit () {
    echo
    if [ -e "$current_wave_file" -a -e "$current_flac_file" ]; then
        red "Cleaning up partially encoded \"$current_flac_file\""
        rm "$current_flac_file"
    fi
    exit
}
trap clean_up_and_exit SIGINT

for current_wave_file in "$@"; do
    if [ ! -e "$current_wave_file" ]; then
        red "\"$current_wave_file\" does not exist"
    elif [ "$(file --mime-type --brief "$current_wave_file")" = "audio/x-wav" ]; then
        PREVIOUS_SIZE="$(wc -c "$current_wave_file" | awk '{print $1}')"
        blue "Encoding \"$current_wave_file\"... (Before: $(filesize "$current_wave_file"))"
        current_flac_file="$(strip_extension "$current_wave_file").flac"
        flac \
                --delete-input-file \
                --keep-foreign-metadata \
                --verify \
            "$current_wave_file"
        if [ "$?" = 0 ]; then
            blue "Done! (After: $(filesize "$current_flac_file" $PREVIOUS_SIZE))"
        else
            red 'flac exited with and error!'
        fi
    else
        red "\"$current_wave_file\" not a wave file"
    fi
done