#!/usr/bin/env python
# -*- coding: utf-8 -*-


"""
cue script that gets called by liquidsoap if a file in the playlist
gives orders to cue (in/out). eg:
cue_file:cue_in=120.0,cue_out=110.0:annotate:***

params:  path_to_file, cue_in [float, seconds], cue_out [float, sseconds]
returns: path to the cued temp-file

examples:
calling: ./cue_file.py /storage/pypo/cache/2010-06-25-15-05-00/35.mp3 10 120.095
returns: /tmp/lstf_UwDKcEngvF

One thing to mention here:
The way pypo (ab)uses liquidsoap can bring in some unwanted effects. liquidsoap 
is built in a way that it tries to collect the needed files to playout in advance.
we 'force' liquidsoap to immediately start playing a newly loaded list, so ls has
no time to prepare the files. If a file is played without cues, this does not afect
the playout too much. My testing on a lame VM added a delay of +/- 10ms.

If the first file in  a playlist is cued, the "mp3cut" command takes time to execute.
On the same VM this takes an additional 200ms for an average size mp3-file.
So the playout will start a bit delayed. This should not be a too big issue, but
think about this behaviour if you eg access the files via network (nas) as the reading
of files could take some time as well.

So maybe we should think about a different implementation. One way would be to do the
cueing during playlist preparation, so all the files would be pre-cut when they are 
passed to liquidsoap. 
Additionally this would allow to run an unpathed version of ls.

"""

import sys
import shutil
import random
import string
import time
from datetime import timedelta
import os

from mutagen.mp3 import MP3
import mad

TEMP_DIR = '/tmp/';


sys.stderr.write('\n** starting mp3 cutter **\n\n')

try: src = sys.argv[1]
except Exception, e: 
    sys.stderr.write('No file givien. sorry.\n')
    sys.exit()

try: cue_in = float(sys.argv[2])
except Exception, e: 
    cue_in = float(0)
    pass

try: cue_out = float(sys.argv[3])
except Exception, e:
    cue_out = float(0)
    pass

sys.stderr.write('in: %s - out: %s file: %s \n' % (cue_in, cue_out, src))
dst = TEMP_DIR + 'lstf_' + "".join( [random.choice(string.letters) for i in xrange(10)] )

# get length of track
"""
madlib is not accurate enough to get the duration. (only goes to seconds, no ms)
so it is not suitable for relative offsets (eg "play until 10s before the end")
it anyway wuld be better to provide this script with absolute times, like
play from 23.234 to 323.321
"""
# madlib
#mf = mad.MadFile(src)
#dur = float(float(mf.total_time())/1000)

# mutagen
audio = MP3(src)
dur = round(audio.info.length, 3)


sys.stderr.write('duration: ' + str(dur) + '\n')

cue_out = round(float(dur) - cue_out, 3)

str_cue_in = str(timedelta(seconds=cue_in)).replace(".", "+") # hh:mm:ss+mss, eg 00:00:20+000
str_cue_out = str(timedelta(seconds=cue_out)).replace(".", "+") #

"""
now a bit a hackish part, don't know how to do this better...
need to cut the digits after the "+"

"""
ts = str_cue_in.split("+")
try:
    if len(ts[1]) == 6:
        ts[1] = ts[1][0:3]
        str_cue_in = "%s+%s" % (ts[0], ts[1])
except Exception, e:
    pass

ts = str_cue_out.split("+")
try:
    if len(ts[1]) == 6:
        ts[1] = ts[1][0:3]
        str_cue_out = "%s+%s" % (ts[0], ts[1])
except Exception, e:
    pass

#sys.stderr.write(str(timedelta(seconds=cue_in)).replace(".", "+") + '\n\n')
sys.stderr.write('in:       ' + str_cue_in + '\n')
sys.stderr.write('abs:      ' + str(str_cue_out) + '\n\n')

command = 'mp3cut -o %s -t %s-%s %s' % (dst, str_cue_in, str_cue_out, src);

sys.stderr.write(command + '\n\n\n')
os.system(command + ' >/dev/null')
#shutil.copy2(src, dst)

print dst + "\n";