# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.


from twisted.trial import unittest
from twisted.protocols import loopback
from twisted.protocols import basic
from twisted.internet import protocol, abstract

import StringIO

class BufferingServer(protocol.Protocol):
buffer = ''
def dataReceived(self, data):
self.buffer += data

class FileSendingClient(protocol.Protocol):
def __init__(self, f):
self.f = f

def connectionMade(self):
s = basic.FileSender()
d = s.beginFileTransfer(self.f, self.transport, lambda x: x)
d.addCallback(lambda r: self.transport.loseConnection())

class FileSenderTestCase(unittest.TestCase):
def testSendingFile(self):
testStr = 'xyz' * 100 + 'abc' * 100 + '123' * 100
s = BufferingServer()
c = FileSendingClient(StringIO.StringIO(testStr))

d = loopback.loopbackTCP(s, c)
d.addCallback(lambda x : self.assertEqual(s.buffer, testStr))
return d

def testSendingEmptyFile(self):
fileSender = basic.FileSender()
consumer = abstract.FileDescriptor()
consumer.connected = 1
emptyFile = StringIO.StringIO('')

d = fileSender.beginFileTransfer(emptyFile, consumer, lambda x: x)

# The producer will be immediately exhausted, and so immediately
# unregistered
self.assertEqual(consumer.producer, None)

# Which means the Deferred from FileSender should have been called
self.failUnless(d.called,
'producer unregistered with deferred being called')