#!/usr/bin/python
# Convert mp3 file(s) to ogg file(s)
# This 'script' uses subprocess to call lame (or ffmpeg) to decode
#  mp3 files into wav files, then oggenc to encode the wav files into
#  ogg files.
# - preserves (easy)id3 tags
# - upgraded to use parallelpython
# TODO: try using gstreamer? recurse through subdirs?
# TODO: exception handling is very messy atm
 
#from mutagen.mp3 import MP3
#from mutagen import File
#from mutagen.easyid3 import EasyID3
import mutagen, mutagen.mp3, mutagen.easyid3
import sys, os, subprocess, optparse
from optparse import OptionParser as OP
#from glob import glob
 
 
op = OP()
op.add_option('-q','--quality',dest='q',type="float",
        help='Ogg quality setting. (defautl: %default)',default=2,metavar='N')
op.add_option('-Q','--quiet',action="store_true",dest="quiet",default=False)
op.add_option('-v','--verbose',action="store_false",dest="quiet")
#op.add_option('-r',action="store_true",dest='recurse',default=False,help='Recurse through subdirectories (NI)')
op.add_option('-d','--directory',help='Move ogg files to specified directory.')
op.add_option('--ffmpeg',action="store_true",default=False,help='Use ffmpeg instead of lame, may help if mp3 has errors.')
op.add_option('-p','--parallel',action='store_true',default=False,help='Use parallelpython to utilize SMP.')
#op.add_option('-g','--gst',action='store_true',default=False,help='Use gstreamer to transcode. (NI)')
op.add_option('-r','--raw',action='store_true',default=False,help='Decode to raw PCM instead of wav (to exceed 2gb limit).')
op.add_option('-o','--options',type="string",help='Pass extra options to oggenc (like rate/channels for raw pcm)',default='')
op.add_option('-t','--transcode',action='store_true',default=False,help='Use ffmpeg\'s transcoding (vorbis) instead of an intermediate wav.  Implies --ffmpeg')
 
def convert(file, cmd, ops):
    """
        This function converts the specified mp3 file, using the specified
        subprocess command, and puts it in the specified directory.
        @file - mp3 filename
        @cmd  - subprocess command (generated below)
        @ops  - optparse Values() class
    """
    oggfile = file[:-3]+'ogg'
    if ops.directory:
        oggfile = os.path.join(ops.directory,oggfile)
 
    print 'Converting "%s" to "%s"...' % (file,oggfile)
    ret = subprocess.call(cmd % (file, oggfile), shell=True)
    if ret < 0:
        print >>sys.stderr, 'Error processing "%s"->: ' % (file,oggfile), -ret
        exit()
 
    # copy tags if mp3
    if file[-3:] == 'mp3':
        # copy tags 
        print 'Copying tags from "%s" to "%s"...' % (file, oggfile)
        mp3 = mutagen.mp3.MP3(file, ID3=mutagen.easyid3.EasyID3)
        ogg = mutagen.File(oggfile)
        ogg.update(mp3)
        ogg.save()
    
    return oggfile
 
def done(*args):
    """
        This function just prints a message when a parallel task finishes.
    """
    print 'Task finished: "%s"' % args[0]
 
#******##******##******# START #******##******##******#
 
# Parse Args
(ops, args) = op.parse_args()
 
files = args
 
# If pp is desired, see if it is available
if ops.parallel:
    try:
        import pp
        js = pp.Server(secret='paw')
        jt = pp.Template(js, convert, (optparse._repr,), # fix for Values() _repr function in pworker
            ('subprocess','os','mutagen','mutagen.mp3','mutagen.easyid3','optparse'), callback=done)
    except Exception, e:
        print 'Could not start pp, reverting to serial: ',e
        ops.parallel = False
 
# default subprocess commands
#cmd = ['lame --decode ','oggenc -q%.1f ' % ops.q]
 
if ops.q < 0 or ops.q > 10:
    print 'Error: Expecting 0 < q < 10.'
    exit()
 
if ops.parallel:
    ops.quiet = True # can't see output anyway...
if ops.transcode:
    ops.ffmpeg = True
quiet = ''
if ops.quiet:
    quiet = ' --quiet '
    ops.options += ' -Q '
 
# generate subprocess command
if ops.ffmpeg:
    if ops.transcode:
        cmd = 'ffmpeg -i "%s" -acodec libvorbis -aq' + ' %02d ' % (ops.q*10) + '"%s"'   # can be vorbis or libvorbis, on debian/buntu libvorbis doesn't seem to work...
    else:
        if ops.raw:         # oggenc expects 16b little endian, not sure what signed/unsiged has to do with anything
            cmd = 'ffmpeg -i "%s" -f s16le - | oggenc -r - ' +ops.options+ '-q%02.1f' % (ops.q) + ' -o "%s"'
        else:  
            cmd = 'ffmpeg -i "%s" -f wav - | oggenc - ' +ops.options+ '-q%02.1f' % (ops.q) + ' -o "%s"'
else:
    if ops.raw:
        cmd = 'lame '+quiet+' --decode -t "%s" - | oggenc -r - ' +ops.options+ '-q%02.1f' % (ops.q) + ' -o "%s"'
    else:
        cmd = 'lame '+quiet+' --decode "%s" - | oggenc - ' +ops.options+ '-q%02.1f' % (ops.q) + ' -o "%s"'
 
 
 
# If directory doesn't exist, create it
if ops.directory:
    if not os.path.isdir(ops.directory):
        try:
            os.mkdir(ops.directory)
        except Exception, e:
            print 'Error: could not create directory %s :' % ops.directory, e
            exit()
 
            
 
for file in files:
    if file[-3:] == 'mp3' or ops.ffmpeg:
        try:
            if ops.parallel:
                jt.submit(file, cmd, ops)
            else:
                convert(file, cmd, ops)
        except Exception, e:
            print >> sys.stderr, 'Execution failed: ',e
            exit()
            
    
if ops.parallel:
    js.wait()
    js.print_stats()