import os
import shutil

from twisted.internet import defer, threads, error
from twisted.trial import unittest

from lbrynet import conf
from lbrynet import lbryfile
from lbrynet import reflector
from lbrynet.core import BlobManager
from lbrynet.core import PeerManager
from lbrynet.core import RateLimiter
from lbrynet.core import Session
from lbrynet.core import StreamDescriptor
from lbrynet.lbryfile import EncryptedFileMetadataManager
from lbrynet.lbryfile.client import EncryptedFileOptions
from lbrynet.lbryfilemanager import EncryptedFileCreator
from lbrynet.lbryfilemanager import EncryptedFileManager

from tests import mocks


class TestReflector(unittest.TestCase):
    def setUp(self):
        self.session = None
        self.stream_info_manager = None
        self.lbry_file_manager = None
        self.server_blob_manager = None
        self.reflector_port = None
        self.addCleanup(self.take_down_env)

    def take_down_env(self):
        d = defer.succeed(True)
        if self.lbry_file_manager is not None:
            d.addCallback(lambda _: self.lbry_file_manager.stop())
        if self.session is not None:
            d.addCallback(lambda _: self.session.shut_down())
        if self.stream_info_manager is not None:
            d.addCallback(lambda _: self.stream_info_manager.stop())
        if self.server_blob_manager is not None:
            d.addCallback(lambda _: self.server_blob_manager.stop())
        if self.reflector_port is not None:
            d.addCallback(lambda _: self.reflector_port.stopListening())

        def delete_test_env():
            try:
                shutil.rmtree('client')
            except:
                raise unittest.SkipTest("TODO: fix this for windows")

        d.addCallback(lambda _: threads.deferToThread(delete_test_env))
        d.addErrback(lambda err: str(err))
        return d

    def test_reflector(self):
        wallet = mocks.Wallet()
        peer_manager = PeerManager.PeerManager()
        peer_finder = mocks.PeerFinder(5553, peer_manager, 2)
        hash_announcer = mocks.Announcer()
        rate_limiter = RateLimiter.DummyRateLimiter()
        sd_identifier = StreamDescriptor.StreamDescriptorIdentifier()

        self.expected_blobs = [
            (
                'dc4708f76a5e7af0f1cae0ee96b824e2ed9250c9346c093b'
                '441f0a20d3607c17948b6fcfb4bc62020fe5286693d08586',
                2097152
            ),
            (
                'f4067522c1b49432a2a679512e3917144317caa1abba0c04'
                '1e0cd2cf9f635d4cf127ce1824fa04189b63916174951f70',
                2097152
            ),
            (
                '305486c434260484fcb2968ce0e963b72f81ba56c11b08b1'
                'af0789b55b44d78422600f9a38e3cf4f2e9569897e5646a9',
                1015056
            ),
        ]

        db_dir = "client"
        os.mkdir(db_dir)

        self.session = Session.Session(
            conf.MIN_BLOB_DATA_PAYMENT_RATE,
            db_dir=db_dir,
            lbryid="abcd",
            peer_finder=peer_finder,
            hash_announcer=hash_announcer,
            blob_dir=None,
            peer_port=5553,
            use_upnp=False,
            rate_limiter=rate_limiter,
            wallet=wallet
        )

        self.stream_info_manager = EncryptedFileMetadataManager.TempEncryptedFileMetadataManager()

        self.lbry_file_manager = EncryptedFileManager.EncryptedFileManager(
            self.session, self.stream_info_manager, sd_identifier)

        self.server_blob_manager = BlobManager.TempBlobManager(hash_announcer)

        d = self.session.setup()
        d.addCallback(lambda _: self.stream_info_manager.setup())
        d.addCallback(lambda _: EncryptedFileOptions.add_lbry_file_to_sd_identifier(sd_identifier))
        d.addCallback(lambda _: self.lbry_file_manager.setup())
        d.addCallback(lambda _: self.server_blob_manager.setup())

        def verify_equal(sd_info):
            self.assertEqual(mocks.create_stream_sd_file, sd_info)

        def save_sd_blob_hash(sd_hash):
            self.expected_blobs.append((sd_hash, 923))

        def verify_stream_descriptor_file(stream_hash):
            d = lbryfile.get_sd_info(self.lbry_file_manager.stream_info_manager, stream_hash, True)
            d.addCallback(verify_equal)
            d.addCallback(
                lambda _: lbryfile.publish_sd_blob(
                    self.lbry_file_manager.stream_info_manager,
                    self.session.blob_manager, stream_hash
                )
            )
            d.addCallback(save_sd_blob_hash)
            d.addCallback(lambda _: stream_hash)
            return d

        def create_stream():
            test_file = mocks.GenFile(5209343, b''.join([chr(i + 3) for i in xrange(0, 64, 6)]))
            d = EncryptedFileCreator.create_lbry_file(
                self.session,
                self.lbry_file_manager,
                "test_file",
                test_file,
                key="0123456701234567",
                iv_generator=iv_generator()
            )
            return d

        def start_server():
            server_factory = reflector.ServerFactory(peer_manager, self.server_blob_manager)
            from twisted.internet import reactor
            port = 8943
            while self.reflector_port is None:
                try:
                    self.reflector_port = reactor.listenTCP(port, server_factory)
                except error.CannotListenError:
                    port += 1
            return defer.succeed(port)

        def send_to_server(port, stream_hash):
            factory = reflector.ClientFactory(
                self.session.blob_manager,
                self.stream_info_manager,
                stream_hash
            )

            from twisted.internet import reactor
            reactor.connectTCP('localhost', port, factory)
            return factory.finished_deferred

        def verify_blob_completed(blob, blob_size):
            self.assertTrue(blob.is_validated())
            self.assertEqual(blob_size, blob.length)

        def verify_have_blob(blob_hash, blob_size):
            d = self.server_blob_manager.get_blob(blob_hash, True)
            d.addCallback(lambda blob: verify_blob_completed(blob, blob_size))
            return d

        def verify_data_on_reflector():
            check_blob_ds = []
            for blob_hash, blob_size in self.expected_blobs:
                check_blob_ds.append(verify_have_blob(blob_hash, blob_size))
            return defer.DeferredList(check_blob_ds)

        def upload_to_reflector(stream_hash):
            d = start_server()
            d.addCallback(lambda port: send_to_server(port, stream_hash))
            d.addCallback(lambda _: verify_data_on_reflector())
            return d

        d.addCallback(lambda _: create_stream())
        d.addCallback(verify_stream_descriptor_file)
        d.addCallback(upload_to_reflector)
        return d


def iv_generator():
    iv = 0
    while True:
        iv += 1
        yield "%016d" % iv
