import socket
import types
from unittest import mock
from unittest.mock import patch

import pytest

import redis
from redis.backoff import NoBackoff
from redis.connection import Connection, HiredisParser, PythonParser
from redis.exceptions import ConnectionError, InvalidResponse, TimeoutError
from redis.retry import Retry
from redis.utils import HIREDIS_AVAILABLE

from .conftest import skip_if_server_version_lt
from .mocks import MockSocket


@pytest.mark.skipif(HIREDIS_AVAILABLE, reason="PythonParser only")
@pytest.mark.onlynoncluster
def test_invalid_response(r):
    raw = b"x"
    parser = r.connection._parser
    with mock.patch.object(parser._buffer, "readline", return_value=raw):
        with pytest.raises(InvalidResponse) as cm:
            parser.read_response()
    assert str(cm.value) == f"Protocol Error: {raw!r}"


@skip_if_server_version_lt("4.0.0")
@pytest.mark.redismod
def test_loading_external_modules(modclient):
    def inner():
        pass

    modclient.load_external_module("myfuncname", inner)
    assert getattr(modclient, "myfuncname") == inner
    assert isinstance(getattr(modclient, "myfuncname"), types.FunctionType)

    # and call it
    from redis.commands import RedisModuleCommands

    j = RedisModuleCommands.json
    modclient.load_external_module("sometestfuncname", j)

    # d = {'hello': 'world!'}
    # mod = j(modclient)
    # mod.set("fookey", ".", d)
    # assert mod.get('fookey') == d


class TestConnection:
    def test_disconnect(self):
        conn = Connection()
        mock_sock = mock.Mock()
        conn._sock = mock_sock
        conn.disconnect()
        mock_sock.shutdown.assert_called_once()
        mock_sock.close.assert_called_once()
        assert conn._sock is None

    def test_disconnect__shutdown_OSError(self):
        """An OSError on socket shutdown will still close the socket."""
        conn = Connection()
        mock_sock = mock.Mock()
        conn._sock = mock_sock
        conn._sock.shutdown.side_effect = OSError
        conn.disconnect()
        mock_sock.shutdown.assert_called_once()
        mock_sock.close.assert_called_once()
        assert conn._sock is None

    def test_disconnect__close_OSError(self):
        """An OSError on socket close will still clear out the socket."""
        conn = Connection()
        mock_sock = mock.Mock()
        conn._sock = mock_sock
        conn._sock.close.side_effect = OSError
        conn.disconnect()
        mock_sock.shutdown.assert_called_once()
        mock_sock.close.assert_called_once()
        assert conn._sock is None

    def clear(self, conn):
        conn.retry_on_error.clear()

    def test_retry_connect_on_timeout_error(self):
        """Test that the _connect function is retried in case of a timeout"""
        conn = Connection(retry_on_timeout=True, retry=Retry(NoBackoff(), 3))
        origin_connect = conn._connect
        conn._connect = mock.Mock()

        def mock_connect():
            # connect only on the last retry
            if conn._connect.call_count <= 2:
                raise socket.timeout
            else:
                return origin_connect()

        conn._connect.side_effect = mock_connect
        conn.connect()
        assert conn._connect.call_count == 3
        self.clear(conn)

    def test_connect_without_retry_on_os_error(self):
        """Test that the _connect function is not being retried in case of a OSError"""
        with patch.object(Connection, "_connect") as _connect:
            _connect.side_effect = OSError("")
            conn = Connection(retry_on_timeout=True, retry=Retry(NoBackoff(), 2))
            with pytest.raises(ConnectionError):
                conn.connect()
            assert _connect.call_count == 1
            self.clear(conn)

    def test_connect_timeout_error_without_retry(self):
        """Test that the _connect function is not being retried if retry_on_timeout is
        set to False"""
        conn = Connection(retry_on_timeout=False)
        conn._connect = mock.Mock()
        conn._connect.side_effect = socket.timeout

        with pytest.raises(TimeoutError) as e:
            conn.connect()
        assert conn._connect.call_count == 1
        assert str(e.value) == "Timeout connecting to server"
        self.clear(conn)


@pytest.mark.onlynoncluster
@pytest.mark.parametrize(
    "parser_class", [PythonParser, HiredisParser], ids=["PythonParser", "HiredisParser"]
)
def test_connection_parse_response_resume(r: redis.Redis, parser_class):
    """
    This test verifies that the Connection parser,
    be that PythonParser or HiredisParser,
    can be interrupted at IO time and then resume parsing.
    """
    if parser_class is HiredisParser and not HIREDIS_AVAILABLE:
        pytest.skip("Hiredis not available)")
    args = dict(r.connection_pool.connection_kwargs)
    args["parser_class"] = parser_class
    conn = Connection(**args)
    conn.connect()
    message = (
        b"*3\r\n$7\r\nmessage\r\n$8\r\nchannel1\r\n"
        b"$25\r\nhi\r\nthere\r\n+how\r\nare\r\nyou\r\n"
    )
    mock_socket = MockSocket(message, interrupt_every=2)

    if isinstance(conn._parser, PythonParser):
        conn._parser._buffer._sock = mock_socket
    else:
        conn._parser._sock = mock_socket
    for i in range(100):
        try:
            response = conn.read_response()
            break
        except MockSocket.TestError:
            pass

    else:
        pytest.fail("didn't receive a response")
    assert response
    assert i > 0