import base64
import io
import mock

from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives.asymmetric import rsa
from cryptography.hazmat.primitives import serialization
from twisted.internet import defer
from twisted.python.failure import Failure

from lbrynet.p2p.client.ClientRequest import ClientRequest
from lbrynet.p2p.Error import RequestCanceledError
from lbrynet.p2p import BlobAvailability
from lbrynet.blob.EncryptedFileManager import EncryptedFileManager
from lbrynet.dht.node import Node as RealNode
from lbrynet.extras.daemon import ExchangeRateManager as ERM, conf

KB = 2**10
PUBLIC_EXPONENT = 65537  # http://www.daemonology.net/blog/2009-06-11-cryptographic-right-answers.html


def decode_rsa_key(pem_key):
    decoded = base64.b64decode(''.join(pem_key.splitlines()[1:-1]))
    return serialization.load_der_public_key(decoded, default_backend())


class FakeLBRYFile:
    def __init__(self, blob_manager, stream_info_manager, stream_hash, uri="fake_uri"):
        self.blob_manager = blob_manager
        self.stream_info_manager = stream_info_manager
        self.stream_hash = stream_hash
        self.file_name = 'fake_lbry_file'


class Node(RealNode):
    def joinNetwork(self, known_node_addresses=None):
        return defer.succeed(None)

    def stop(self):
        return defer.succeed(None)

    def start(self, known_node_addresses=None):
        return self.joinNetwork(known_node_addresses)


class FakeNetwork:
    @staticmethod
    def get_local_height():
        return 1

    @staticmethod
    def get_server_height():
        return 1


class BTCLBCFeed(ERM.MarketFeed):
    def __init__(self):
        ERM.MarketFeed.__init__(
            self,
            "BTCLBC",
            "market name",
            "derp.com",
            None,
            0.0
        )


class USDBTCFeed(ERM.MarketFeed):
    def __init__(self):
        ERM.MarketFeed.__init__(
            self,
            "USDBTC",
            "market name",
            "derp.com",
            None,
            0.0
        )


class ExchangeRateManager(ERM.ExchangeRateManager):
    def __init__(self, market_feeds, rates):
        self.market_feeds = market_feeds
        for feed in self.market_feeds:
            feed.rate = ERM.ExchangeRate(
                feed.market, rates[feed.market]['spot'], rates[feed.market]['ts'])


class PointTraderKeyExchanger:

    def __init__(self, wallet):
        self.wallet = wallet
        self._protocols = []

    def send_next_request(self, peer, protocol):
        if not protocol in self._protocols:
            r = ClientRequest({'public_key': self.wallet.encoded_public_key.decode()},
                              'public_key')
            d = protocol.add_request(r)
            d.addCallback(self._handle_exchange_response, peer, r, protocol)
            d.addErrback(self._request_failed, peer)
            self._protocols.append(protocol)
            return defer.succeed(True)
        else:
            return defer.succeed(False)

    def _handle_exchange_response(self, response_dict, peer, request, protocol):
        assert request.response_identifier in response_dict, \
            "Expected %s in dict but did not get it" % request.response_identifier
        assert protocol in self._protocols, "Responding protocol is not in our list of protocols"
        peer_pub_key = response_dict[request.response_identifier]
        self.wallet.set_public_key_for_peer(peer, peer_pub_key)
        return True

    def _request_failed(self, err, peer):
        if not err.check(RequestCanceledError):
            return err


class PointTraderKeyQueryHandlerFactory:

    def __init__(self, wallet):
        self.wallet = wallet

    def build_query_handler(self):
        q_h = PointTraderKeyQueryHandler(self.wallet)
        return q_h

    def get_primary_query_identifier(self):
        return 'public_key'

    def get_description(self):
        return ("Point Trader Address - an address for receiving payments on the "
                "point trader testing network")


class PointTraderKeyQueryHandler:

    def __init__(self, wallet):
        self.wallet = wallet
        self.query_identifiers = ['public_key']
        self.public_key = None
        self.peer = None

    def register_with_request_handler(self, request_handler, peer):
        self.peer = peer
        request_handler.register_query_handler(self, self.query_identifiers)

    def handle_queries(self, queries):
        if self.query_identifiers[0] in queries:
            new_encoded_pub_key = queries[self.query_identifiers[0]]
            try:
                decode_rsa_key(new_encoded_pub_key)
            except (ValueError, TypeError, IndexError):
                value_error = ValueError(f"Client sent an invalid public key: {new_encoded_pub_key}")
                return defer.fail(Failure(value_error))
            self.public_key = new_encoded_pub_key
            self.wallet.set_public_key_for_peer(self.peer, self.public_key)
            fields = {'public_key': self.wallet.encoded_public_key.decode()}
            return defer.succeed(fields)
        if self.public_key is None:
            return defer.fail(Failure(ValueError("Expected but did not receive a public key")))
        else:
            return defer.succeed({})


class Wallet:
    def __init__(self):
        self.private_key = rsa.generate_private_key(public_exponent=PUBLIC_EXPONENT,
                                                    key_size=1024, backend=default_backend())
        self.encoded_public_key = self.private_key.public_key().public_bytes(serialization.Encoding.PEM,
                                                                             serialization.PublicFormat.PKCS1)
        self._config = None
        self.network = None
        self.wallet = None
        self.is_first_run = False
        self.printed_retrieving_headers = False
        self._start_check = None
        self._catch_up_check = None
        self._caught_up_counter = 0
        self._lag_counter = 0
        self.blocks_behind = 0
        self.catchup_progress = 0
        self.max_behind = 0

    def start(self):
        return defer.succeed(True)

    def stop(self):
        return defer.succeed(True)

    def get_info_exchanger(self):
        return PointTraderKeyExchanger(self)

    def update_peer_address(self, peer, address):
        pass

    def get_wallet_info_query_handler_factory(self):
        return PointTraderKeyQueryHandlerFactory(self)

    def get_unused_address_for_peer(self, peer):
        return defer.succeed("bDtL6qriyimxz71DSYjojTBsm6cpM1bqmj")

    def reserve_points(self, *args):
        return True

    def cancel_point_reservation(self, *args):
        pass

    def send_points(self, *args):
        return defer.succeed(True)

    def add_expected_payment(self, *args):
        pass

    def get_balance(self):
        return defer.succeed(1000)

    def set_public_key_for_peer(self, peer, public_key):
        pass

    def get_claim_metadata_for_sd_hash(self, sd_hash):
        return "fakeuri", "aa04a949348f9f094d503e5816f0cfb57ee68a22f6d08d149217d071243e0377", 1

    def get_claimid(self, name, txid=None, nout=None):
        return "aa04a949348f9f094d503e5816f0cfb57ee68a22f6d08d149217d071243e0378"


class PeerFinder:
    def __init__(self, start_port, peer_manager, num_peers):
        self.start_port = start_port
        self.peer_manager = peer_manager
        self.num_peers = num_peers
        self.count = 0

    def find_peers_for_blob(self, h, filter_self=False):
        peer_port = self.start_port + self.count
        self.count += 1
        if self.count >= self.num_peers:
            self.count = 0
        return defer.succeed([self.peer_manager.get_peer("127.0.0.1", peer_port)])

    def run_manage_loop(self):
        pass

    def stop(self):
        pass


class Announcer:
    def __init__(self, *args):
        pass

    def hash_queue_size(self):
        return 0

    def immediate_announce(self, *args):
        pass

    def start(self):
        pass

    def stop(self):
        pass


class GenFile(io.RawIOBase):
    def __init__(self, size, pattern):
        io.RawIOBase.__init__(self)
        self.size = size
        self.pattern = pattern
        self.read_so_far = 0
        self.buff = b''
        self.last_offset = 0
        self.name = "."

    def readable(self):
        return True

    def writable(self):
        return False

    def read(self, n=-1):
        if n > -1:
            bytes_to_read = min(n, self.size - self.read_so_far)
        else:
            bytes_to_read = self.size - self.read_so_far
        output, self.buff = self.buff[:bytes_to_read], self.buff[bytes_to_read:]
        bytes_to_read -= len(output)
        while bytes_to_read > 0:
            self.buff = self._generate_chunk()
            new_output, self.buff = self.buff[:bytes_to_read], self.buff[bytes_to_read:]
            bytes_to_read -= len(new_output)
            output += new_output
        self.read_so_far += len(output)
        return output

    def readall(self):
        return self.read()

    def _generate_chunk(self, size=KB):
        output = self.pattern[self.last_offset:self.last_offset + size]
        n_left = size - len(output)
        whole_patterns = n_left // len(self.pattern)
        output += self.pattern * whole_patterns
        self.last_offset = size - len(output)
        output += self.pattern[:self.last_offset]
        return output


class BlobAvailabilityTracker(BlobAvailability.BlobAvailabilityTracker):
    """
    Class to track peer counts for known blobs, and to discover new popular blobs

    Attributes:
        availability (dict): dictionary of peers for known blobs
    """

    def __init__(self, blob_manager=None, peer_finder=None, dht_node=None):
        self.availability = {
            '91dc64cf1ff42e20d627b033ad5e4c3a4a96856ed8a6e3fb'
            '4cd5fa1cfba4bf72eefd325f579db92f45f4355550ace8e7': ['1.2.3.4'],
            'b2e48bb4c88cf46b76adf0d47a72389fae0cd1f19ed27dc5'
            '09138c99509a25423a4cef788d571dca7988e1dca69e6fa0': ['1.2.3.4', '1.2.3.4'],
            '6af95cd062b4a179576997ef1054c9d2120f8592eea045e9'
            '667bea411d520262cd5a47b137eabb7a7871f5f8a79c92dd':
                ['1.2.3.4', '1.2.3.4', '1.2.3.4'],
            '6d8017aba362e5c5d0046625a039513419810a0397d72831'
            '8c328a5cc5d96efb589fbca0728e54fe5adbf87e9545ee07':
                ['1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4'],
            '5a450b416275da4bdff604ee7b58eaedc7913c5005b7184f'
            'c3bc5ef0b1add00613587f54217c91097fc039ed9eace9dd':
                ['1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4'],
            'd7c82e6cac093b3f16107d2ae2b2c75424f1fcad2c7fbdbe'
            '66e4a13c0b6bd27b67b3a29c403b82279ab0f7c1c48d6787':
                ['1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4'],
            '9dbda74a472a2e5861a5d18197aeba0f5de67c67e401124c'
            '243d2f0f41edf01d7a26aeb0b5fc9bf47f6361e0f0968e2c':
                ['1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4'],
            '8c70d5e2f5c3a6085006198e5192d157a125d92e73787944'
            '72007a61947992768926513fc10924785bdb1761df3c37e6':
                ['1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4',
                 '1.2.3.4'],
            'f99d24cd50d4bfd77c2598bfbeeb8415bf0feef21200bdf0'
            'b8fbbde7751a77b7a2c68e09c25465a2f40fba8eecb0b4e0':
                ['1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4',
                 '1.2.3.4', '1.2.3.4'],
            'c84aa1fd8f5009f7c4e71e444e40d95610abc1480834f835'
            'eefb267287aeb10025880a3ce22580db8c6d92efb5bc0c9c':
                ['1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4', '1.2.3.4',
                 '1.2.3.4', '1.2.3.4', '1.2.3.4'],
        }
        self._blob_manager = None
        self._peer_finder = PeerFinder(11223, 11224, 2)
        self._dht_node = None
        self._check_popular = None
        self._check_mine = None
        self._set_mean_peers()

    def start(self):
        pass

    def stop(self):
        pass


# The components below viz. FakeWallet, FakeSession, FakeFileManager are just for testing Component Manager's
# startup and stop
class FakeComponent:
    depends_on = []
    component_name = None

    def __init__(self, component_manager):
        self.component_manager = component_manager
        self._running = False

    @property
    def running(self):
        return self._running

    def start(self):
        raise NotImplementedError  # Override

    def stop(self):
        return defer.succeed(None)

    @property
    def component(self):
        return self

    @defer.inlineCallbacks
    def _setup(self):
        result = yield defer.maybeDeferred(self.start)
        self._running = True
        defer.returnValue(result)

    @defer.inlineCallbacks
    def _stop(self):
        result = yield defer.maybeDeferred(self.stop)
        self._running = False
        defer.returnValue(result)

    def __lt__(self, other):
        return self.component_name < other.component_name


class FakeDelayedWallet(FakeComponent):
    component_name = "wallet"
    depends_on = []

    def start(self):
        return defer.succeed(True)

    def stop(self):
        d = defer.Deferred()
        self.component_manager.reactor.callLater(1, d.callback, True)
        return d


class FakeDelayedBlobManager(FakeComponent):
    component_name = "blob_manager"
    depends_on = [FakeDelayedWallet.component_name]

    def start(self):
        d = defer.Deferred()
        self.component_manager.reactor.callLater(1, d.callback, True)
        return d

    def stop(self):
        d = defer.Deferred()
        self.component_manager.reactor.callLater(1, d.callback, True)
        return d


class FakeDelayedFileManager(FakeComponent):
    component_name = "file_manager"
    depends_on = [FakeDelayedBlobManager.component_name]

    def start(self):
        d = defer.Deferred()
        self.component_manager.reactor.callLater(1, d.callback, True)
        return d

    def stop(self):
        return defer.succeed(True)


class FakeFileManager(FakeComponent):
    component_name = "file_manager"
    depends_on = []

    @property
    def component(self):
        return mock.Mock(spec=EncryptedFileManager)

    def start(self):
        return defer.succeed(True)

    def stop(self):
        pass

    def get_status(self):
        return {}


create_stream_sd_file = {
    'stream_name': '746573745f66696c65',
    'blobs': [
        {
            'length': 2097152,
            'blob_num': 0,
            'blob_hash': 'dc4708f76a5e7af0f1cae0ee96b824e2ed9250c9346c093b'
                         '441f0a20d3607c17948b6fcfb4bc62020fe5286693d08586',
            'iv': '30303030303030303030303030303031'
        },
        {
            'length': 2097152,
            'blob_num': 1,
            'blob_hash': 'f4067522c1b49432a2a679512e3917144317caa1abba0c04'
                         '1e0cd2cf9f635d4cf127ce1824fa04189b63916174951f70',
            'iv': '30303030303030303030303030303032'
        },
        {
            'length': 1015056,
            'blob_num': 2,
            'blob_hash': '305486c434260484fcb2968ce0e963b72f81ba56c11b08b1'
                         'af0789b55b44d78422600f9a38e3cf4f2e9569897e5646a9',
            'iv': '30303030303030303030303030303033'
        },
        {'length': 0, 'blob_num': 3, 'iv': '30303030303030303030303030303034'}
    ],
    'stream_type': 'lbryfile',
    'key': '30313233343536373031323334353637',
    'suggested_file_name': '746573745f66696c65',
    'stream_hash': '6d27fbe10c86d81aacfb897c7a426d0a2214f5a299455a6d'
                   '315c0f998c4b3545c2dc60906122d94653c23b1898229e3f'
}


def mock_conf_settings(obj, settings={}):
    conf.settings = None
    settings.setdefault('download_mirrors', [])
    conf.initialize_settings(False)
    original_settings = conf.settings
    conf.settings = conf.Config(conf.FIXED_SETTINGS, conf.ADJUSTABLE_SETTINGS)
    conf.settings.installation_id = conf.settings.get_installation_id()
    conf.settings.node_id = conf.settings.get_node_id()
    conf.settings.update(settings)

    def _reset_settings():
        conf.settings = original_settings

    obj.addCleanup(_reset_settings)