#!/usr/bin/ruby
#
# Copyright (C) 2007 - Mike Rowehl - mike@rowehl.com
#
# Takes a mail message sent by the Ultimate Voice Recorder app for Nokia S60
# devices and convert it into MP3 format.  The assumed input format is amr.
# The transcoded file is checked into a subversion repository.
#
# This work is placed in the public domain:
# http://creativecommons.org/licenses/publicdomain/
#

require 'pathname'
require 'rubygems'
require 'rmail'
require 'base64'


module CmdRunner
  def lsys( cmd )
    system( cmd + " > /dev/null 2>&1" )
  end
end


class VoiceRecorderEmail
  include CmdRunner
  attr_reader :filename, :body, :date, :time, :mp3

  def initialize( text )
    @msg = RMail::Parser.read( text )

    @msg.each_part { |part|
      if part.header.include?( 'Content-Disposition' )
        cd = part.header['Content-Disposition']
	fileinfo = cd.match( /filename="([^"]+)"/ )
	if fileinfo
	  @filename = fileinfo[1]
	  @body = part.body
          matches = @filename.match( /Memo_(........)_(......)/ )
	  @date = matches[1]
	  @time = matches[2]
	end
      end
    }
  end

  def date_time
    @date + '_' + @time
  end

  def raw_amr
    Base64.decode64( @body )
  end

  def convert_to_mp3
    amr_converter = '/home/mike/src/amr/c-code/decoder'
    wav_tool = '/usr/bin/sox'
    mp3_tool = '/usr/local/bin/lame'

    amr_name = "/tmp/#{$$}_#{date_time}.amr"
    raw_name = "/tmp/#{$$}_#{date_time}.raw"
    wav_name = "/tmp/#{$$}_#{date_time}.wav"
    mp3_name = "/tmp/#{$$}_#{date_time}.mp3"

    decode_cmd = "#{amr_converter} #{amr_name} #{raw_name}"
    wav_cmd = "#{wav_tool} -r 8000 -w -c 1 -s #{raw_name} -w -c 1 #{wav_name}"
    mp3_cmd = "#{mp3_tool} #{wav_name} #{mp3_name} --silent"

    amr_file = File.new( amr_name, 'w+' )
    amr_file.write( raw_amr )
    amr_file.close

    # print decode_cmd + "\n"
    lsys( decode_cmd )
    # print wav_cmd + "\n"
    lsys( wav_cmd )
    # print mp3_cmd + "\n"
    lsys( mp3_cmd )

    mp3_file = File.open( mp3_name )
    @mp3 = mp3_file.read
    mp3_file.close

    File.unlink( amr_name, raw_name, wav_name, mp3_name )

    true
  end
end


class SubversionSandbox
  include CmdRunner

  def initialize( date )
    @sandbox_root = '/home/mike/rowehl'
    @relative_path = 'personal/audio'
    audio_path = File.join( @sandbox_root, @relative_path );
    @date = date
    @dir = Pathname.new( File.join( audio_path, date ) )
  end

  def add_recording( time, mp3 )
    Dir.chdir( @sandbox_root )

    day_path = File.join( @relative_path, @date )
    day_dir = Pathname.new( day_path )
    note_path = File.join( day_path, time + '.mp3' )
    note_file = Pathname.new( note_path )

    if ! day_dir.exist?
      day_dir.mkdir
      svn_dir_add = "svn add #{day_path}"
      # print svn_dir_add + "\n"
      lsys( svn_dir_add )
    end

    if note_file.exist?
      return
    end

    file = File.new( note_path, 'w+' )
    file.write( mp3 )
    file.close

    svn_add = "svn add #{note_path}"
    # print svn_add + "\n"
    lsys( svn_add )
    svn_ci = "svn ci -m \"Adding audio note #{@date} #{time}\""
    # print svn_ci + "\n"
    lsys( svn_ci )
  end
end


raw_email = $stdin.read()

vre = VoiceRecorderEmail.new( raw_email )
date = vre.date
time = vre.time
# print "#{date} #{time}\n"
if vre.convert_to_mp3
  repos = SubversionSandbox.new( date )
  repos.add_recording( time, vre.mp3 )
end