# Written by Bram Cohen
# see LICENSE.txt for license information
 
from zurllib import urlopen
from urlparse import urlparse
from BT1.btformats import check_message
from BT1.Choker import Choker
from BT1.Storage import Storage
from BT1.StorageWrapper import StorageWrapper
from BT1.FileSelector import FileSelector
from BT1.Uploader import Upload
from BT1.Downloader import Downloader
from BT1.HTTPDownloader import HTTPDownloader
from BT1.Connecter import Connecter
from RateLimiter import RateLimiter
from BT1.Encrypter import Encoder
from RawServer import RawServer, autodetect_ipv6, autodetect_socket_style
from BT1.Rerequester import Rerequester
from BT1.DownloaderFeedback import DownloaderFeedback
from RateMeasure import RateMeasure
from CurrentRateMeasure import Measure
from BT1.PiecePicker import PiecePicker
from BT1.Statistics import Statistics
from ConfigDir import ConfigDir
from bencode import bencode, bdecode
from natpunch import UPnP_test
from hashlib import sha1
from os import path, makedirs, listdir
from parseargs import parseargs, formatDefinitions, defaultargs
from socket import error as socketerror
from random import seed
from threading import Thread, Event
from clock import clock
from BTcrypto import CRYPTO_OK
from __init__ import createPeerID
 
try:
    True
except:
    True = 1
    False = 0
 
defaults = [
    ('max_uploads', 7,
        "the maximum number of uploads to allow at once."),
    ('keepalive_interval', 120.0,
        'number of seconds to pause between sending keepalives'),
    ('download_slice_size', 2 ** 14,
        "How many bytes to query for per request."),
    ('upload_unit_size', 1460,
        "when limiting upload rate, how many bytes to send at a time"),
    ('request_backlog', 10,
        "maximum number of requests to keep in a single pipe at once."),
    ('max_message_length', 2 ** 23,
        "maximum length prefix encoding you'll accept over the wire - larger values get the connection dropped."),
    ('ip', '',
        "ip to report you have to the tracker."),
    ('minport', 10000, 'minimum port to listen on, counts up if unavailable'),
    ('maxport', 60000, 'maximum port to listen on'),
    ('random_port', 1, 'whether to choose randomly inside the port range ' +
        'instead of counting up linearly'),
    ('responsefile', '',
        'file the server response was stored in, alternative to url'),
    ('url', '',
        'url to get file from, alternative to responsefile'),
    ('crypto_allowed', int(CRYPTO_OK),
        'whether to allow the client to accept encrypted connections'),
    ('crypto_only', 0,
        'whether to only create or allow encrypted connections'),
    ('crypto_stealth', 0,
        'whether to prevent all non-encrypted connection attempts; ' +
        'will result in an effectively firewalled state on older trackers'),
    ('selector_enabled', 1,
        'whether to enable the file selector and fast resume function'),
    ('expire_cache_data', 10,
        'the number of days after which you wish to expire old cache data ' +
        '(0 = disabled)'),
    ('priority', '',
        'a list of file priorities separated by commas, must be one per file, ' +
        '0 = highest, 1 = normal, 2 = lowest, -1 = download disabled'),
    ('saveas', '',
        'local file name to save the file as, null indicates query user'),
    ('timeout', 300.0,
        'time to wait between closing sockets which nothing has been received on'),
    ('timeout_check_interval', 60.0,
        'time to wait between checking if any connections have timed out'),
    ('max_slice_length', 2 ** 17,
        "maximum length slice to send to peers, larger requests are ignored"),
    ('max_rate_period', 20.0,
        "maximum amount of time to guess the current rate estimate represents"),
    ('bind', '', 
        'comma-separated list of ips/hostnames to bind to locally'),
#    ('ipv6_enabled', autodetect_ipv6(),
    ('ipv6_enabled', 0,
         'allow the client to connect to peers via IPv6'),
    ('ipv6_binds_v4', autodetect_socket_style(),
        "set if an IPv6 server socket won't also field IPv4 connections"),
    ('upnp_nat_access', 1,
        'attempt to autoconfigure a UPnP router to forward a server port ' +
        '(0 = disabled, 1 = mode 1 [fast], 2 = mode 2 [slow])'),
    ('upload_rate_fudge', 5.0, 
        'time equivalent of writing to kernel-level TCP buffer, for rate adjustment'),
    ('tcp_ack_fudge', 0.03,
        'how much TCP ACK download overhead to add to upload rate calculations ' +
        '(0 = disabled)'),
    ('display_interval', .5,
        'time between updates of displayed information'),
    ('rerequest_interval', 5 * 60,
        'time to wait between requesting more peers'),
    ('min_peers', 20, 
        'minimum number of peers to not do rerequesting'),
    ('http_timeout', 60, 
        'number of seconds to wait before assuming that an http connection has timed out'),
    ('max_initiate', 40,
        'number of peers at which to stop initiating new connections'),
    ('check_hashes', 1,
        'whether to check hashes on disk'),
    ('max_upload_rate', 0,
        'maximum kB/s to upload at (0 = no limit, -1 = automatic)'),
    ('max_download_rate', 0,
        'maximum kB/s to download at (0 = no limit)'),
    ('alloc_type', 'normal',
        'allocation type (may be normal, background, pre-allocate or sparse)'),
    ('alloc_rate', 2.0,
        'rate (in MiB/s) to allocate space at using background allocation'),
    ('buffer_reads', 1,
        'whether to buffer disk reads'),
    ('write_buffer_size', 4,
        'the maximum amount of space to use for buffering disk writes ' +
        '(in megabytes, 0 = disabled)'),
    ('breakup_seed_bitfield', 1,
        'sends an incomplete bitfield and then fills with have messages, '
        'in order to get around stupid ISP manipulation'),
    ('snub_time', 30.0,
        "seconds to wait for data to come in over a connection before assuming it's semi-permanently choked"),
    ('spew', 0,
        "whether to display diagnostic info to stdout"),
    ('rarest_first_cutoff', 2,
        "number of downloads at which to switch from random to rarest first"),
    ('rarest_first_priority_cutoff', 5,
        'the number of peers which need to have a piece before other partials take priority over rarest first'),
    ('min_uploads', 4,
        "the number of uploads to fill out to with extra optimistic unchokes"),
    ('max_files_open', 50,
        'the maximum number of files to keep open at a time, 0 means no limit'),
    ('round_robin_period', 30,
        "the number of seconds between the client's switching upload targets"),
    ('super_seeder', 0,
        "whether to use special upload-efficiency-maximizing routines (only for dedicated seeds)"),
    ('security', 1,
        "whether to enable extra security features intended to prevent abuse"),
    ('max_connections', 0,
        "the absolute maximum number of peers to connect with (0 = no limit)"),
    ('auto_kick', 1,
        "whether to allow the client to automatically kick/ban peers that send bad data"),
    ('double_check', 1,
        "whether to double-check data being written to the disk for errors (may increase CPU load)"),
    ('triple_check', 0,
        "whether to thoroughly check data being written to the disk (may slow disk access)"),
    ('lock_files', 1,
        "whether to lock files the client is working with"),
    ('lock_while_reading', 0,
        "whether to lock access to files being read"),
    ('auto_flush', 0,
        "minutes between automatic flushes to disk (0 = disabled)"),
    ('dedicated_seed_id', '',
        "code to send to tracker identifying as a dedicated seed"),
    ]
 
argslistheader = 'Arguments are:\n\n'
 
 
def _failfunc(x):
    print x
 
# old-style downloader
def download(params, filefunc, statusfunc, finfunc, errorfunc, doneflag, cols,
             pathFunc = None, presets = {}, exchandler = None,
             failed = _failfunc, paramfunc = None):
 
    try:
        config = parse_params(params, presets)
    except ValueError, e:
        failed('error: ' + str(e) + '\nrun with no args for parameter explanations')
        return
    if not config:
        errorfunc(get_usage())
        return
 
    myid = createPeerID()
    seed(myid)
 
    rawserver = RawServer(doneflag, config['timeout_check_interval'],
                          config['timeout'], ipv6_enable = config['ipv6_enabled'],
                          failfunc = failed, errorfunc = exchandler)
 
    upnp_type = UPnP_test(config['upnp_nat_access'])
    try:
        listen_port = rawserver.find_and_bind(config['minport'], config['maxport'],
                        config['bind'], ipv6_socket_style = config['ipv6_binds_v4'],
                        upnp = upnp_type, randomizer = config['random_port'])
    except socketerror, e:
        failed("Couldn't listen - " + str(e))
        return
 
    response = get_response(config['responsefile'], config['url'], failed)
    if not response:
        return
 
    infohash = sha1(bencode(response['info'])).digest()
 
    d = BT1Download(statusfunc, finfunc, errorfunc, exchandler, doneflag,
                    config, response, infohash, myid, rawserver, listen_port)
 
    if not d.saveAs(filefunc):
        return
 
    if pathFunc:
        pathFunc(d.getFilename())
 
    hashcheck = d.initFiles(old_style = True)
    if not hashcheck:
        return
    if not hashcheck():
        return
    if not d.startEngine():
        return
    d.startRerequester()
    d.autoStats()
 
    statusfunc(activity = 'connecting to peers')
 
    if paramfunc:
        paramfunc({ 'max_upload_rate' : d.setUploadRate,  # change_max_upload_rate(<int KiB/sec>)
                    'max_uploads': d.setConns, # change_max_uploads(<int max uploads>)
                    'listen_port' : listen_port, # int
                    'peer_id' : myid, # string
                    'info_hash' : infohash, # string
                    'start_connection' : d._startConnection, # start_connection((<string ip>, <int port>), <peer id>)
                    })
 
    rawserver.listen_forever(d.getPortHandler())
 
    d.shutdown()
 
 
def parse_params(params, presets = {}):
    if len(params) == 0:
        return None
    config, args = parseargs(params, defaults, 0, 1, presets = presets)
    if args:
        if config['responsefile'] or config['url']:
            raise ValueError,'must have responsefile or url as arg or parameter, not both'
        if path.isfile(args[0]):
            config['responsefile'] = args[0]
        else:
            try:
                urlparse(args[0])
            except:
                raise ValueError, 'bad filename or url'
            config['url'] = args[0]
    elif (config['responsefile'] == '') == (config['url'] == ''):
        raise ValueError, 'need responsefile or url, must have one, cannot have both'
    return config
 
 
def get_usage(defaults = defaults, cols = 100, presets = {}):
    return (argslistheader + formatDefinitions(defaults, cols, presets))
 
 
def get_response(file, url, errorfunc):
    try:
        if file:
            h = open(file, 'rb')
            try:
                line = h.read(10)   # quick test to see if responsefile contains a dict
                front,garbage = line.split(':',1)
                assert front[0] == 'd'
                int(front[1:])
            except:
                errorfunc(file+' is not a valid responsefile')
                return None
            try:
                h.seek(0)
            except:
                try:
                    h.close()
                except:
                    pass
                h = open(file, 'rb')
        else:
            try:
                h = urlopen(url)
            except:
                errorfunc(url+' bad url')
                return None
        response = h.read()
 
    except IOError, e:
        errorfunc('problem getting response info - ' + str(e))
        return None
    try:    
        h.close()
    except:
        pass
    try:
        try:
            response = bdecode(response)
        except:
            errorfunc("warning: bad data in responsefile")
            response = bdecode(response, sloppy=1)
        check_message(response)
    except ValueError, e:
        errorfunc("got bad file info - " + str(e))
        return None
 
    return response
 
 
class BT1Download:    
    def __init__(self, statusfunc, finfunc, errorfunc, excfunc, doneflag,
                 config, response, infohash, id, rawserver, port,
                 appdataobj = None):
        self.statusfunc = statusfunc
        self.finfunc = finfunc
        self.errorfunc = errorfunc
        self.excfunc = excfunc
        self.doneflag = doneflag
        self.config = config
        self.response = response
        self.infohash = infohash
        self.myid = id
        self.rawserver = rawserver
        self.port = port
 
        self.info = self.response['info']
        self.pieces = [self.info['pieces'][x:x+20]
                       for x in xrange(0, len(self.info['pieces']), 20)]
        self.len_pieces = len(self.pieces)
        self.argslistheader = argslistheader
        self.unpauseflag = Event()
        self.unpauseflag.set()
        self.downloader = None
        self.storagewrapper = None
        self.fileselector = None
        self.super_seeding_active = False
        self.filedatflag = Event()
        self.spewflag = Event()
        self.superseedflag = Event()
        self.whenpaused = None
        self.finflag = Event()
        self.rerequest = None
        self.tcp_ack_fudge = config['tcp_ack_fudge']
 
        self.selector_enabled = config['selector_enabled']
        if appdataobj:
            self.appdataobj = appdataobj
        elif self.selector_enabled:
            self.appdataobj = ConfigDir()
            self.appdataobj.deleteOldCacheData( config['expire_cache_data'],
                                                [self.infohash] )
 
        self.excflag = self.rawserver.get_exception_flag()
        self.failed = False
        self.checking = False
        self.started = False
 
        self.picker = PiecePicker(self.len_pieces, config['rarest_first_cutoff'],
                             config['rarest_first_priority_cutoff'])
        self.choker = Choker(config, rawserver.add_task,
                             self.picker, self.finflag.isSet)
 
 
    def checkSaveLocation(self, loc):
        if self.info.has_key('length'):
            return path.exists(loc)
        for x in self.info['files']:
            if path.exists(path.join(loc, x['path'][0])):
                return True
        return False
 
 
    def saveAs(self, filefunc, pathfunc = None):
        try:
            def make(f, forcedir = False):
                if not forcedir:
                    f = path.split(f)[0]
                if f != '' and not path.exists(f):
                    makedirs(f)
 
            if self.info.has_key('length'):
                file_length = self.info['length']
                file = filefunc(self.info['name'], file_length,
                                self.config['saveas'], False)
                if file is None:
                    return None
                make(file)
                files = [(file, file_length)]
            else:
                file_length = 0L
                for x in self.info['files']:
                    file_length += x['length']
                file = filefunc(self.info['name'], file_length,
                                self.config['saveas'], True)
                if file is None:
                    return None
 
                # if this path exists, and no files from the info dict exist, we assume it's a new download and 
                # the user wants to create a new directory with the default name
                existing = 0
                if path.exists(file):
                    if not path.isdir(file):
                        self.errorfunc(file + 'is not a dir')
                        return None
                    if len(listdir(file)) > 0:  # if it's not empty
                        for x in self.info['files']:
                            if path.exists(path.join(file, x['path'][0])):
                                existing = 1
                        if not existing:
                            file = path.join(file, self.info['name'])
                            if path.exists(file) and not path.isdir(file):
                                if file[-8:] == '.torrent':
                                    file = file[:-8]
                                if path.exists(file) and not path.isdir(file):
                                    self.errorfunc("Can't create dir - " + self.info['name'])
                                    return None
                make(file, True)
 
                # alert the UI to any possible change in path
                if pathfunc != None:
                    pathfunc(file)
 
                files = []
                for x in self.info['files']:
                    n = file
                    for i in x['path']:
                        n = path.join(n, i)
                    files.append((n, x['length']))
                    make(n)
        except OSError, e:
            self.errorfunc("Couldn't allocate dir - " + str(e))
            return None
 
        self.filename = file
        self.files = files
        self.datalength = file_length
 
        return file
 
 
    def getFilename(self):
        return self.filename
 
 
    def _finished(self):
        self.finflag.set()
        try:
            self.storage.set_readonly()
        except (IOError, OSError), e:
            self.errorfunc('trouble setting readonly at end - ' + str(e))
        if self.superseedflag.isSet():
            self._set_super_seed()
        self.choker.set_round_robin_period(
            max( self.config['round_robin_period'],
                 self.config['round_robin_period'] *
                                     self.info['piece length'] / 200000 ) )
        self.rerequest_complete()
        self.finfunc()
 
    def _data_flunked(self, amount, index):
        self.ratemeasure_datarejected(amount)
        if not self.doneflag.isSet():
            self.errorfunc('piece %d failed hash check, re-downloading it' % index)
 
    def _failed(self, reason):
        self.failed = True
        self.doneflag.set()
        if reason is not None:
            self.errorfunc(reason)
 
 
    def initFiles(self, old_style = False, statusfunc = None):
        if self.doneflag.isSet():
            return None
        if not statusfunc:
            statusfunc = self.statusfunc
 
        disabled_files = None
        if self.selector_enabled:
            self.priority = self.config['priority']
            if self.priority:
                try:
                    self.priority = self.priority.split(',')
                    assert len(self.priority) == len(self.files)
                    self.priority = [int(p) for p in self.priority]
                    for p in self.priority:
                        assert p >= -1
                        assert p <= 2
                except:
                    self.errorfunc('bad priority list given, ignored')
                    self.priority = None
 
            data = self.appdataobj.getTorrentData(self.infohash)
            try:
                d = data['resume data']['priority']
                assert len(d) == len(self.files)
                disabled_files = [x == -1 for x in d]
            except:
                try:
                    disabled_files = [x == -1 for x in self.priority]
                except:
                    pass
 
        try:
            try:
                self.storage = Storage(self.files, self.info['piece length'],
                                       self.doneflag, self.config, disabled_files)
            except IOError, e:
                self.errorfunc('trouble accessing files - ' + str(e))
                return None
            if self.doneflag.isSet():
                return None
 
            self.storagewrapper = StorageWrapper(self.storage, self.config['download_slice_size'],
                self.pieces, self.info['piece length'], self._finished, self._failed,
                statusfunc, self.doneflag, self.config['check_hashes'],
                self._data_flunked, self.rawserver.add_task,
                self.config, self.unpauseflag)
 
        except ValueError, e:
            self._failed('bad data - ' + str(e))
        except IOError, e:
            self._failed('IOError - ' + str(e))
        if self.doneflag.isSet():
            return None
 
        if self.selector_enabled:
            self.fileselector = FileSelector(self.files, self.info['piece length'],
                                             self.appdataobj.getPieceDir(self.infohash),
                                             self.storage, self.storagewrapper,
                                             self.rawserver.add_task,
                                             self._failed)
            if data:
                data = data.get('resume data')
                if data:
                    self.fileselector.unpickle(data)
 
        self.checking = True
        if old_style:
            return self.storagewrapper.old_style_init()
        return self.storagewrapper.initialize
 
 
    def getCachedTorrentData(self):
        return self.appdataobj.getTorrentData(self.infohash)
 
 
    def _make_upload(self, connection, ratelimiter, totalup):
        return Upload(connection, ratelimiter, totalup,
                      self.choker, self.storagewrapper, self.picker,
                      self.config)
 
    def _kick_peer(self, connection):
        def k(connection = connection):
            connection.close()
        self.rawserver.add_task(k,0)
 
    def _ban_peer(self, ip):
        self.encoder_ban(ip)
 
    def _received_raw_data(self, x):
        if self.tcp_ack_fudge:
            x = int(x*self.tcp_ack_fudge)
            self.ratelimiter.adjust_sent(x)
 
    def _received_data(self, x):
        self.downmeasure.update_rate(x)
        self.ratemeasure.data_came_in(x)
 
    def _received_http_data(self, x):
        self.downmeasure.update_rate(x)
        self.ratemeasure.data_came_in(x)
        self.downloader.external_data_received(x)
 
    def _cancelfunc(self, pieces):
        self.downloader.cancel_piece_download(pieces)
        self.httpdownloader.cancel_piece_download(pieces)
    def _reqmorefunc(self, pieces):
        self.downloader.requeue_piece_download(pieces)
 
    def startEngine(self, ratelimiter = None, statusfunc = None):
        if self.doneflag.isSet():
            return False
        if not statusfunc:
            statusfunc = self.statusfunc
 
        self.checking = False
 
        if not CRYPTO_OK:
            if self.config['crypto_allowed']:
                self.errorfunc('warning - crypto library not installed')
            self.config['crypto_allowed'] = 0
            self.config['crypto_only'] = 0
            self.config['crypto_stealth'] = 0
 
        for i in xrange(self.len_pieces):
            if self.storagewrapper.do_I_have(i):
                self.picker.complete(i)
        self.upmeasure = Measure(self.config['max_rate_period'],
                            self.config['upload_rate_fudge'])
        self.downmeasure = Measure(self.config['max_rate_period'])
 
        if ratelimiter:
            self.ratelimiter = ratelimiter
        else:
            self.ratelimiter = RateLimiter(self.rawserver.add_task,
                                           self.config['upload_unit_size'],
                                           self.setConns)
            self.ratelimiter.set_upload_rate(self.config['max_upload_rate'])
 
        self.ratemeasure = RateMeasure()
        self.ratemeasure_datarejected = self.ratemeasure.data_rejected
 
        self.downloader = Downloader(self.storagewrapper, self.picker,
            self.config['request_backlog'], self.config['max_rate_period'],
            self.len_pieces, self.config['download_slice_size'],
            self._received_data, self.config['snub_time'], self.config['auto_kick'],
            self._kick_peer, self._ban_peer)
        self.downloader.set_download_rate(self.config['max_download_rate'])
        self.connecter = Connecter(self._make_upload, self.downloader, self.choker,
                            self.len_pieces, self.upmeasure, self.config,
                            self.ratelimiter, self.rawserver.add_task)
        self.encoder = Encoder(self.connecter, self.rawserver,
            self.myid, self.config['max_message_length'], self.rawserver.add_task,
            self.config['keepalive_interval'], self.infohash,
            self._received_raw_data, self.config)
        self.encoder_ban = self.encoder.ban
 
        self.httpdownloader = HTTPDownloader(self.storagewrapper, self.picker,
            self.rawserver, self.finflag, self.errorfunc, self.downloader,
            self.config['max_rate_period'], self.infohash, self._received_http_data,
            self.connecter.got_piece)
        if self.response.has_key('httpseeds') and not self.finflag.isSet():
            for u in self.response['httpseeds']:
                self.httpdownloader.make_download(u)
 
        if self.selector_enabled:
            self.fileselector.tie_in(self.picker, self._cancelfunc,
                    self._reqmorefunc, self.rerequest_ondownloadmore)
            if self.priority:
                self.fileselector.set_priorities_now(self.priority)
            self.appdataobj.deleteTorrentData(self.infohash)
                                # erase old data once you've started modifying it
 
        if self.config['super_seeder']:
            self.set_super_seed()
 
        self.started = True
        return True
 
 
    def rerequest_complete(self):
        if self.rerequest:
            self.rerequest.announce(1)
 
    def rerequest_stopped(self):
        if self.rerequest:
            self.rerequest.announce(2)
 
    def rerequest_lastfailed(self):
        if self.rerequest:
            return self.rerequest.last_failed
        return False
 
    def rerequest_ondownloadmore(self):
        if self.rerequest:
            self.rerequest.hit()
 
    def startRerequester(self, seededfunc = None, force_rapid_update = False):
        if self.response.has_key('announce-list'):
            trackerlist = self.response['announce-list']
        else:
            trackerlist = [[self.response['announce']]]
 
        self.rerequest = Rerequester(self.port, self.myid, self.infohash, 
            trackerlist, self.config, 
            self.rawserver.add_task, self.rawserver.add_task,
            self.errorfunc, self.excfunc,
            self.encoder.start_connections,
            self.connecter.how_many_connections, 
            self.storagewrapper.get_amount_left, 
            self.upmeasure.get_total, self.downmeasure.get_total,
            self.upmeasure.get_rate, self.downmeasure.get_rate,
            self.doneflag, self.unpauseflag, seededfunc, force_rapid_update )
 
        self.rerequest.start()
 
 
    def _init_stats(self):
        self.statistics = Statistics(self.upmeasure, self.downmeasure,
                    self.connecter, self.httpdownloader, self.ratelimiter,
                    self.rerequest_lastfailed, self.filedatflag)
        if self.info.has_key('files'):
            self.statistics.set_dirstats(self.files, self.info['piece length'])
        if self.config['spew']:
            self.spewflag.set()
 
    def autoStats(self, displayfunc = None):
        if not displayfunc:
            displayfunc = self.statusfunc
 
        self._init_stats()
        DownloaderFeedback(self.choker, self.httpdownloader, self.rawserver.add_task,
            self.upmeasure.get_rate, self.downmeasure.get_rate,
            self.ratemeasure, self.storagewrapper.get_stats,
            self.datalength, self.finflag, self.spewflag, self.statistics,
            displayfunc, self.config['display_interval'])
 
    def startStats(self):
        self._init_stats()
        d = DownloaderFeedback(self.choker, self.httpdownloader, self.rawserver.add_task,
            self.upmeasure.get_rate, self.downmeasure.get_rate,
            self.ratemeasure, self.storagewrapper.get_stats,
            self.datalength, self.finflag, self.spewflag, self.statistics)
        return d.gather
 
 
    def getPortHandler(self):
        return self.encoder
 
 
    def shutdown(self, torrentdata = {}):
        if self.checking or self.started:
            self.storagewrapper.sync()
            self.storage.close()
            self.rerequest_stopped()
        if self.fileselector and self.started:
            if not self.failed:
                self.fileselector.finish()
                torrentdata['resume data'] = self.fileselector.pickle()
            try:
                self.appdataobj.writeTorrentData(self.infohash,torrentdata)
            except:
                self.appdataobj.deleteTorrentData(self.infohash) # clear it
        return not self.failed and not self.excflag.isSet()
        # if returns false, you may wish to auto-restart the torrent
 
 
    def setUploadRate(self, rate):
        try:
            def s(self = self, rate = rate):
                self.config['max_upload_rate'] = rate
                self.ratelimiter.set_upload_rate(rate)
            self.rawserver.add_task(s)
        except AttributeError:
            pass
 
    def setConns(self, conns, conns2 = None):
        if not conns2:
            conns2 = conns
        try:
            def s(self = self, conns = conns, conns2 = conns2):
                self.config['min_uploads'] = conns
                self.config['max_uploads'] = conns2
                if (conns > 30):
                    self.config['max_initiate'] = conns + 10
            self.rawserver.add_task(s)
        except AttributeError:
            pass
 
    def setDownloadRate(self, rate):
        try:
            def s(self = self, rate = rate):
                self.config['max_download_rate'] = rate
                self.downloader.set_download_rate(rate)
            self.rawserver.add_task(s)
        except AttributeError:
            pass
 
    def startConnection(self, ip, port, id):
        self.encoder._start_connection((ip, port), id)
 
    def _startConnection(self, ipandport, id):
        self.encoder._start_connection(ipandport, id)
 
    def setInitiate(self, initiate):
        try:
            def s(self = self, initiate = initiate):
                self.config['max_initiate'] = initiate
            self.rawserver.add_task(s)
        except AttributeError:
            pass
 
    def getConfig(self):
        return self.config
 
    def getDefaults(self):
        return defaultargs(defaults)
 
    def getUsageText(self):
        return self.argslistheader
 
    def reannounce(self, special = None):
        try:
            def r(self = self, special = special):
                if special is None:
                    self.rerequest.announce()
                else:
                    self.rerequest.announce(specialurl = special)
            self.rawserver.add_task(r)
        except AttributeError:
            pass
 
    def getResponse(self):
        try:
            return self.response
        except:
            return None
 
    def Pause(self):
        if not self.storagewrapper:
            return False
        self.unpauseflag.clear()
        self.rawserver.add_task(self.onPause)
        return True
 
    def onPause(self):
        self.whenpaused = clock()
        if not self.downloader:
            return
        self.downloader.pause(True)
        self.encoder.pause(True)
        self.choker.pause(True)
 
    def Unpause(self):
        self.unpauseflag.set()
        self.rawserver.add_task(self.onUnpause)
 
    def onUnpause(self):
        if not self.downloader:
            return
        self.downloader.pause(False)
        self.encoder.pause(False)
        self.choker.pause(False)
        if self.rerequest and self.whenpaused and clock()-self.whenpaused > 60:
            self.rerequest.announce(3)      # rerequest automatically if paused for >60 seconds
 
    def set_super_seed(self):
        try:
            self.superseedflag.set()
            def s(self = self):
                if self.finflag.isSet():
                    self._set_super_seed()
            self.rawserver.add_task(s)
        except AttributeError:
            pass
 
    def _set_super_seed(self):
        if not self.super_seeding_active:
            self.super_seeding_active = True
            self.errorfunc('        ** SUPER-SEED OPERATION ACTIVE **\n' +
                           '  please set Max uploads so each peer gets 6-8 kB/s')
            def s(self = self):
                self.downloader.set_super_seed()
                self.choker.set_super_seed()
            self.rawserver.add_task(s)
            if self.finflag.isSet():        # mode started when already finished
                def r(self = self):
                    self.rerequest.announce(3)  # so after kicking everyone off, reannounce
                self.rawserver.add_task(r)
 
    def am_I_finished(self):
        return self.finflag.isSet()
 
    def get_transfer_stats(self):
        return self.upmeasure.get_total(), self.downmeasure.get_total()