#!/usr/bin/python

# Joe Gillotti - 3/28/2014

import os
import re
import glob
import sys
import subprocess

torrents = '/srv/media/torrents'
rar = '/usr/bin/rar'
extensions = ('mkv', 'mp4', 'mpg', 'avi', 'm4v', 'wmv')
dryRun = '--dry' in sys.argv

if not os.path.exists(rar):
  print 'Rar not found'
  sys.exit(1)

toExtract = []

for root, dirs, files in os.walk(torrents):
  for fn in files:
    if fn.split('.')[-1] != 'rar':
      continue

    path = os.path.join(root, fn)
    base = fn[:-4]

    if not os.path.exists(os.path.join(root, base+'.r01')):
      continue

    try:
      proc = subprocess.Popen([rar, 'l', path], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
      out = proc.communicate()
    except OSError as e:
      print 'Failed listing rar contents for {0}: {1}'.format(fn, e)
      continue

    # Likely needlessly complex but whatever. Also don't care about files
    # with spaces in their names
    listParsing = False
    destFile = None
    for line in out[0].split('\n'):
      line = line.strip()
      if line == '-'*79:
        if listParsing:
          break
        listParsing = True

      if listParsing:
        name = line.split(' ')[0]
        if name.split('.')[-1] in extensions:
          destFile = name
          break

    if destFile is None:
      continue

    result = os.path.join(root, name)

    if not os.path.exists(result):
      toExtract.append(os.path.join(root, fn))

# Extracting after the fact as os.chdir'ing inside os.walk breaks things
for path in toExtract:
      folder = os.path.dirname(path)
      base = os.path.basename(path)
      print 'Extracting {0}...'.format(base)
      
      if dryRun:
        continue

      try:
        os.chdir(folder)
      except OSError as e:
        print 'Failed cding into {0}: {1}'.format(folder, e)

      try:
        subprocess.Popen([rar, 'x', base]).wait()
      except OSError as e:
        print 'Failed extracting {0}: {1}'.format(base, e)