#!/usr/bin/env python

# User details
# Add the url to your feed
feed_url = "http://yourrssfeed/here.xml"
down_path = "/path/to/download/torrents/"
logs_path = "/root/.config/gettorrentsbyrss/"

hist = logs_path + "rss-hist.txt"   # Location of history file
inc  = logs_path + "rss-inc.txt"    # Location of incoming links file
diff = logs_path + "rss-diff.txt"   # Location of difference file.
evnt = down_path + "errorlog.txt"   # Location of simple log

# Transmission RPC details
# Fill in your transmission details below
USER = 'Your_RPC_Login_Here'        # Username
PASS = 'Enter_RPC_password_here'    # Password
HOST = 'localhost'                  # The remote host
PORT = '9091'                       # The same port as used by the server

# ------------------------------------------------------------------------------
# DO NOT MODIFY BELOW THIS LINE UNLESS YOU KNOW WHAT YOU ARE DOING!!
# ------------------------------------------------------------------------------

print "[i] Init libraries.."

# Import some needed libraries
import feedparser
import difflib
import urllib
import urllib2
import transmissionrpc
import datetime, time
import os, sys

# Prepare for logging ----------------------------------------------------------
d = os.path.dirname(evnt)
if not os.path.exists(d):
    os.makedirs(d)
if not os.path.exists(evnt):
    file(evnt, 'w').close()
evntlog = open(evnt, 'a+b')
now = time.strftime("%Y-%m-%d %H:%M:%S", time.localtime())
# ------------------------------------------------------------------------------

evntlog.write(now + " : Script startrn")

print "[i] Connect to the transmission RPC server.."

# Use contents of diff file and add them to transmission via the rpc
try:
   # Connect to the transmission RPC server
   tc = transmissionrpc.Client(HOST, port=PORT, user=USER, password=PASS)
   tc.session_stats()
except:
   print "[Fatal] Transmission error, check config or transmission library (root# easy_install transmissionrpc)"
   evntlog.write(now + " : [Fatal] Transmission errorrn")
   evntlog.close()
   sys.exit(1)

print "[i] Check for log/history/diff files.."

if not os.path.exists(down_path):
    os.makedirs(down_path)

# Create the log files if they do not exist. This will prevent read/write errors later on
d = os.path.dirname(hist)
if not os.path.exists(d):
    os.makedirs(d)
if not os.path.exists(hist):
    file(hist, 'w').close()

d = os.path.dirname(inc)
if not os.path.exists(d):
    os.makedirs(d)
if not os.path.exists(inc):
    file(inc, 'w').close()

d = os.path.dirname(diff)
if not os.path.exists(d):
    os.makedirs(d)
if not os.path.exists(diff):
    file(diff, 'w').close()

print "[i] Parse the feed url.."

# Parse the feed url given in the user details section.
feed = feedparser.parse(feed_url)
# Strip all the unnecessary data and grab the links
with open(inc, 'w+') as incoming_file:
        for post in feed.entries:
                incoming_file.write(post.link + "n")
                #post.title
                #post.link
                #post.comments
                #post.pubDate

print "[i] Check the incoming file against the history.."

# Check the incoming file against the history file. If there is a differece, write it to the diff file.
def build_set(inc):
    # A set stores a collection of unique items.  Both adding items and searching for them
    # are quick, so it's perfect for this application.
    found = set()

    with open(inc) as incoming:
        for line in incoming:
            # [:2] gives us the first two elements of the list.
            # Tuples, unlike lists, cannot be changed, which is a requirement for anything
            # being stored in a set.
            found.add(tuple(sorted(line.split()[:2])))

    return found

set_more = build_set(inc)
set_del = build_set(hist)

with open(diff, 'w+') as difference:
   # Using with to open files ensures that they are properly closed, even if the code
   # raises an exception.

   for res in (set_more - set_del):
      # The - computes the elements in set_more not in set_del.
      difference.write(" ".join(res) + "n")


# Open the diff file and add the contents (links) to transmission
f = open(diff)
for line in iter(f):
   try:
      # Add torrents to transmission via the rpc
      print "   [t] Add task: " + line.strip()
      #time.sleep(5)
      tc.add_torrent(line, download_dir=down_path)
   except transmissionrpc.TransmissionError as error:
      print "   [Error] " + error.message + "rn"
      now = time.strftime("%Y-%m-%d %H:%M:%S", time.localtime())
      evntlog.write(now + " : " + error.message + " (" + line.strip() + ")n")
      pass
f.close()

print "[i] Move contents of diff file and append to history file.."

# Move contents of diff file and append to history file, then reset diff file
# Open diff file, read contents then close file
diff_file = open(diff, "r")
diff_data = diff_file.read()
diff_file.close()
# Open history file and appaend diff file data
hist_file = open(hist, "a")
hist_file.write(diff_data)
hist_file.close()

print "[i] Finishing.."

# Now we have finished with the diff and inc files, we open them, write in nothing and resave the file
open(diff, 'w').close()
open(inc, 'w').close()
evntlog.close()

print "[i] Complete"