#!/bin/bash
# $Id: audiocd-write,v 1.4 2003/07/05 03:07:51 nturner Exp $
#
# audio2cd - make an audio cd from a directory of mp3 or ogg files
#
#            created 04-05-2001 by Tim Winter <invierno@wpi.edu>
#            hacked on by Nathaniel Turner <nturner@no-really.net>
#   
# Depends: mpg123, ogg123, sox, cdrecord
#
# Usage:
#   audio2cd [--keep-temps|--del-temps] [DIR] [TEMP_DIR]
#   
set -e 

function main {

    # Set defaults
    BURN_AS_ROOT=
    KEEP_TEMPFILES=0
    TEST_ONLY=0
    MP3_DECODER=mpg123
    OGG_DECODER=ogg123
    TEMP_PREFIX="/var/tmp/audio2cd-`id -un`-"

    # Read configuration file, if it exists
    if [ -f "/etc/audio2cd.conf" ]; then
        source "/etc/audio2cd.conf"
    fi

    # Read command line parameters
    noMoreParams=0
    while [ "$noMoreParams" = 0 ]; do
        case "$1" in
            --keep-temps|-k)
                shift
                KEEP_TEMPFILES=1
                ;;
            --del-temps|-d)
                shift
                KEEP_TEMPFILES=0
                ;;
            --test-only|-t)
                shift
                TEST_ONLY=1
                ;;
            *)
                noMoreParams=1
                ;;
        esac
    done
    if [ "$1" ]; then 
        srcDir="$1"
    else
        srcDir=`pwd`
    fi
    tmpDir="$TEMP_PREFIX$(basename "$srcDir")"

    # blank line for readability
    echo

    # Verify that source directory exists
    if [ -d "$srcDir" ]; then
        if [ -L "$srcDir" ]; then
            srcDir="$srcDir/."
        fi
        echo "Audio files will be read from '$srcDir'."
        tracks=`find "$srcDir" -maxdepth 1 '(' -name "*.mp3" -o -name "*.ogg" ')' \
                -printf '%f\n' | sort`
        if [ -z "$tracks" ]; then
            echo "Error: The selected directory contains no mp3 or ogg files."
            return 1
        fi
        echo "The audio CD will contain the following tracks:"
        echo "$tracks"
    else
        echo "Error: '$srcDir' is not a directory."
        echo "USAGE: $(basename $0) [sourceDir]"
        return 1
    fi

    # Output some info about the specified options
    if [ "$TEST_ONLY" = 1 ]; then
        echo "This is just a test; a CD will not be written."
    fi
    if [ "$KEEP_TEMPFILES" = 1 ]; then
        echo "Decoded wav files will be retained in $tmpDir."
    else
        echo "Decoded wav files will be deleted after successfully burning the CD."
    fi

    # Create temp directory if it doesn't exist
    if [ ! -d "$tmpDir" ]; then
        mkdir -p "$tmpDir"
    fi

    # Decode compressed audio in $srcDir to wav files in $tmpDir
    decodeFiles "$srcDir" "$tmpDir" || return 1

    # Calculate the total size of the wav files to 
    # make sure they will fit on the CD
    #SIZE=`du -bsS --exclude=*.mp3 "$tmpDir" | awk '{print $1;}'`
    SIZEMB=`du -hsS --exclude=*.mp3 "$tmpDir" | awk '{print $1;}'`
    echo "Total size of .wav files: $SIZEMB"
    echo "Writing CD:"
    cd "$tmpDir" || echo "unable to enter $tmpDir"

    if [ "$TEST_ONLY" = 1 ]; then
        echo "This is a just a test, so not actually burning the CD."
    else
        $BURN_AS_ROOT cdrecord -v -dao -eject -pad -audio *.wav
    fi

    if [ "$PIPESTATUS" = 0 ]; then
        echo "CD successfully written."
        if [ "$KEEP_TEMPFILES" = 1 ]; then
            echo "Leaving temp files in $tmpDir."
        else
            echo -n "Removing temporary files... "
            rm -f "$tmpDir"/*.wav && rmdir "$tmpDir" && echo OK
        fi
    else
        echo "Error: Something went wrong while trying to write the CD."
        return 1
    fi
}

function decodeFiles {
    srcDir="$1"
    tmpDir="$2"

    # For each audio file in $srcDir, make an appropriately formatted wav file
    # in $tmpDir (44.1 kHz, stereo) by decoding and filtering through sox
    find "$srcDir" -maxdepth 1 -name "*.mp3" -o -name "*.ogg" \
            | sort | while read f; do
        f=$(basename "$f")
        if [ ! -f "$tmpDir/$f.wav" ]; then
            case "$f" in
                *.mp3)
                    echo -n "Decoding: $f (using $MP3_DECODER) ... "
                    nice $MP3_DECODER -q -s -r 44100 "$srcDir/$f" \
                            | nice sox -t raw -r 44100 -c 2 -w -s - \
                                   -r 44100 -c 2 -t wav -w -s "$tmpDir/$f.wav" || return 1
                    ;;
                *.ogg)
                    echo -n "Decoding: $f (using $OGG_DECODER) ... "
                    nice $OGG_DECODER -q -d au -f - "$srcDir/$f" 2>/dev/null\
                            | nice sox -t au - \
                                    -r 44100 -c 2 -t wav -w -s "$tmpDir/$f.wav" || return 1
                    ;;
            esac
            if [ "${PIPESTATUS[1]}" = 0 ]; then
                echo "OK"
            else
                echo "Error."
                if [ -f "$tmpDir/$f.wav" ]; then
                    rm "$tmpDir/$f.wav" && \
                    echo "Removed partly decoded tempfile."
                fi
                return 1
            fi
        else
            echo "Using existing wav file for $f."
        fi
    done
}

main "$@"