#!/bin/sh
#
#                 mp3tocd
#                 -------
#
# Pressing an audio CD from multiple mp3-files.
#
# Script by Paul Kremer (paulkremer (AT) gmx (DOT) net)
# License: BSD artistic
#
# needs the following tools:
#  - an mp3 player which can convert to wav (mpg123 or madplay)
#  - sox (Sound eXchange), for correcting wav-files
#  - normalize, to adjust the volume of different mp3's
#  - some gnu-utilities: grep, head, cut and bash
#  - cdrecord
#
#
# The script assumes you have enough disk-space for at least
# one complete audio-cd and that the mp3-files come from
# different sources so they are being "tuned" for better
# quality. The processing with sox and the normalization should
# not be necessary with godd-quality mp3's.
#
# Speed, system load and cdrecord: I have tested this script on
# an old Pentium 100 system with 32 MB RAM, and everything went OK.
#
#Changelog:
#
# 0.1 initial release (june 2001)
# 0.2 minor feature enhancements (july 2001)
#     added command-line options, and nice output to console
#


# Configuration
# -------------
# this regexp will match all lines in a playlist which do not contain
# filenames (like comment lines)
EXCLUDE_REGEXP="^#"

CONVERTCOMMAND="madplay --quiet --output"
#CONVERTCOMMAND="mpg123 -w"
CDBURNCOMMAND="cdrecord -v dev=0,6,0 -eject speed=4 -pad -audio *.wav"

# The main code
#
#

VERSION="0.2"
function help {
   echo "$0 version $VERSION License: BSD Author: Paul Kremer"
   echo ""
   echo "Usage: `basename $0` [OPTION] -f playlist"
   echo ""
   echo "Options:"
   echo "       -b --batch       batch-mode for volumes"
   echo "       -m --mix         mix-mode for volumes"
   echo "       -h --help        displays this message"
   echo "       -f               specify a  playlist file"
   echo ""
   exit 0
}

# this function prepares the mp3-files from the playlist
# == copies them to the current directory
# the parameter for the function is the playlist filename
function playlist_prepare () {
   FNAME="bla"
   echo "  copying mp3 files..."
   let COUNTER=1
   while [ "$FNAME" != "" ]
   do
      read FNAME
      F="`echo -n "$FNAME" | grep -v "$EXCLUDE_REGEXP"`"
      if [ -f "$F" ]; then
         echo "   ... `basename "$F"`"
         cp "$F" "./$COUNTER-`basename "$F" | tr ' ' '_'`"
         let COUNTER=$COUNTER+1
      fi
   done < "${1}"
}

# converts the mp3 files to wav format
function convert_to_wav() {
   echo "  converting to wav..."
   for i in *.mp3
   do
      echo "   ... `basename $i .mp3`"
      nice $CONVERTCOMMAND `basename $i .mp3`.wav $i
      rm "$i"
   done
}

# sox fixes files with bad frequencies
function fix_bad_files() {
BADFILES=`file *.wav | grep -v 44100 | cut -f 1 -d ":"`
if [ "$BADFILES" != "" ]; then
   echo "  fixing frequencies..."
fi
while [ "$BADFILES" != "" ]
do
   BADFILE=`file *.wav | grep -v 44100 | cut -f 1 -d ":" | head -n 1`
   echo "   ...$BADFILE adjusting to 44100 Hz"
   nice sox $BADFILE -r 44100 $BADFILE.new.wav resample
   if [ "$?"  == "0" ]; then
      mv $BADFILE.new.wav $BADFILE
#     echo "  adjusted rate of $BADFILE to 44100 Hz"
   fi
   BADFILES=`file *.wav | grep -v 44100 | cut -f 1 -d ":"`
done
}

# adjust volume level
function normalize_wav() {
   echo "  normalizing volume levels, using $NORMA_MODE ..."
   nice normalize -q $NORMA_MODE *.wav
}

# burn to cd
function burn_to_cd() {
   echo ""
   echo "  starting CDDA burn process..."
   echo "   ... $CDBURNCOMMAND"
}

##################
function do_stuff() {
   echo "Using playlist \"${1}\""
   playlist_prepare "${1}"
   convert_to_wav
   fix_bad_files
   normalize_wav
   burn_to_cd
   exit 0
}


########### MAIN #################
if [ "${1}" == "-f" ]; then
   if [ -f "${2}" ]; then
      NORMA_MODE="-m"
      do_stuff "${2}"
   fi
fi
if [ "${1}" == "-m" ]; then
   NORMA_MODE="-m"
fi
if [ "${1}" == "--mix" ]; then
   NORMA_MODE="-m"
fi
if [ "${1}" == "-b" ]; then
   NORMA_MODE="-b"
fi
if [ "${1}" == "--batch" ]; then
   NORMA_MODE="-b"
fi
if [ "${2}" == "-f" ]; then
   if [ -f "${3}" ]; then
      do_stuff "${3}"
   fi
fi

if [ "a" == "a" ]; then
   help
fi