import copy
import platform
import socket
import sys
import threading
import types
from errno import ECONNREFUSED
from typing import Any
from unittest import mock
from unittest.mock import call, patch

import pytest
import redis
from redis import ConnectionPool, Redis
from redis._parsers import _HiredisParser, _RESP2Parser, _RESP3Parser
from redis.backoff import NoBackoff
from redis.cache import (
    CacheConfig,
    CacheEntry,
    CacheEntryStatus,
    CacheInterface,
    CacheKey,
    DefaultCache,
    LRUPolicy,
)
from redis.connection import (
    CacheProxyConnection,
    Connection,
    SSLConnection,
    UnixDomainSocketConnection,
    parse_url,
)
from redis.credentials import UsernamePasswordCredentialProvider
from redis.exceptions import ConnectionError, InvalidResponse, RedisError, 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, match=f"Protocol Error: {raw!r}"):
            parser.read_response()


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

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

    # and call it
    from redis.commands import RedisModuleCommands

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

    # d = {'hello': 'world!'}
    # mod = j(r)
    # 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_non_retryable_error(self):
        """Test that the _connect function is not being retried in case of a non-retryable error"""
        with patch.object(Connection, "_connect") as _connect:
            _connect.side_effect = RedisError("")
            conn = Connection(retry_on_timeout=True, retry=Retry(NoBackoff(), 2))
            with pytest.raises(RedisError):
                conn.connect()
            assert _connect.call_count == 1
            self.clear(conn)

    def test_connect_with_retries(self):
        """
        Validate that retries occur for the entire connect+handshake flow when OSError
        happens during the handshake phase.
        """
        with patch.object(socket.socket, "sendall") as sendall:
            sendall.side_effect = OSError(ECONNREFUSED)
            conn = Connection(retry_on_timeout=True, retry=Retry(NoBackoff(), 2))
            with pytest.raises(ConnectionError):
                conn.connect()
            # the handshake commands are the failing ones
            # validate that we don't execute too many commands on each retry
            # 3 retries --> 3 commands
            assert sendall.call_count == 3

    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, match="Timeout connecting to server"):
            conn.connect()
        assert conn._connect.call_count == 1
        self.clear(conn)


@pytest.mark.onlynoncluster
@pytest.mark.parametrize(
    "parser_class",
    [_RESP2Parser, _RESP3Parser, _HiredisParser],
    ids=["RESP2Parser", "RESP3Parser", "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, _RESP2Parser) or isinstance(conn._parser, _RESP3Parser):
        conn._parser._buffer._sock = mock_socket
    else:
        conn._parser._sock = mock_socket
    for i in range(100):
        try:
            response = conn.read_response(disconnect_on_error=False)
            break
        except MockSocket.TestError:
            pass

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


@pytest.mark.onlynoncluster
@pytest.mark.parametrize(
    "Class",
    [
        Connection,
        SSLConnection,
        UnixDomainSocketConnection,
    ],
)
def test_pack_command(Class):
    """
    This test verifies that the pack_command works
    on all supported connections. #2581
    """
    cmd = (
        "HSET",
        "foo",
        "key",
        "value1",
        b"key_b",
        b"bytes str",
        b"key_i",
        67,
        "key_f",
        3.14159265359,
    )
    expected = (
        b"*10\r\n$4\r\nHSET\r\n$3\r\nfoo\r\n$3\r\nkey\r\n$6\r\nvalue1\r\n"
        b"$5\r\nkey_b\r\n$9\r\nbytes str\r\n$5\r\nkey_i\r\n$2\r\n67\r\n$5"
        b"\r\nkey_f\r\n$13\r\n3.14159265359\r\n"
    )

    actual = Class().pack_command(*cmd)[0]
    assert actual == expected, f"actual = {actual}, expected = {expected}"


@pytest.mark.onlynoncluster
def test_create_single_connection_client_from_url():
    client = redis.Redis.from_url(
        "redis://localhost:6379/0?", single_connection_client=True
    )
    assert client.connection is not None


@pytest.mark.parametrize("from_url", (True, False), ids=("from_url", "from_args"))
def test_pool_auto_close(request, from_url):
    """Verify that basic Redis instances have auto_close_connection_pool set to True"""

    url: str = request.config.getoption("--redis-url")
    url_args = parse_url(url)

    def get_redis_connection():
        if from_url:
            return Redis.from_url(url)
        return Redis(**url_args)

    r1 = get_redis_connection()
    assert r1.auto_close_connection_pool is True
    r1.close()


@pytest.mark.skipif(sys.version_info == (3, 9), reason="Flacky test on Python 3.9")
@pytest.mark.parametrize("from_url", (True, False), ids=("from_url", "from_args"))
def test_redis_connection_pool(request, from_url):
    """Verify that basic Redis instances using `connection_pool`
    have auto_close_connection_pool set to False"""

    url: str = request.config.getoption("--redis-url")
    url_args = parse_url(url)

    pool = None

    def get_redis_connection():
        nonlocal pool
        if from_url:
            pool = ConnectionPool.from_url(url)
        else:
            pool = ConnectionPool(**url_args)
        return Redis(connection_pool=pool)

    called = 0

    def mock_disconnect(_):
        nonlocal called
        called += 1

    with patch.object(ConnectionPool, "disconnect", mock_disconnect):
        with get_redis_connection() as r1:
            assert r1.auto_close_connection_pool is False

    assert called == 0
    pool.disconnect()


@pytest.mark.parametrize("from_url", (True, False), ids=("from_url", "from_args"))
def test_redis_from_pool(request, from_url):
    """Verify that basic Redis instances created using `from_pool()`
    have auto_close_connection_pool set to True"""

    url: str = request.config.getoption("--redis-url")
    url_args = parse_url(url)

    pool = None

    def get_redis_connection():
        nonlocal pool
        if from_url:
            pool = ConnectionPool.from_url(url)
        else:
            pool = ConnectionPool(**url_args)
        return Redis.from_pool(pool)

    called = 0

    def mock_disconnect(_):
        nonlocal called
        called += 1

    with patch.object(ConnectionPool, "disconnect", mock_disconnect):
        with get_redis_connection() as r1:
            assert r1.auto_close_connection_pool is True

    assert called == 1
    pool.disconnect()


@pytest.mark.parametrize(
    "conn, error, expected_message",
    [
        (SSLConnection(), OSError(), "Error connecting to localhost:6379."),
        (SSLConnection(), OSError(12), "Error 12 connecting to localhost:6379."),
        (
            SSLConnection(),
            OSError(12, "Some Error"),
            "Error 12 connecting to localhost:6379. Some Error.",
        ),
        (
            UnixDomainSocketConnection(path="unix:///tmp/redis.sock"),
            OSError(),
            "Error connecting to unix:///tmp/redis.sock.",
        ),
        (
            UnixDomainSocketConnection(path="unix:///tmp/redis.sock"),
            OSError(12),
            "Error 12 connecting to unix:///tmp/redis.sock.",
        ),
        (
            UnixDomainSocketConnection(path="unix:///tmp/redis.sock"),
            OSError(12, "Some Error"),
            "Error 12 connecting to unix:///tmp/redis.sock. Some Error.",
        ),
    ],
)
def test_format_error_message(conn, error, expected_message):
    """Test that the _error_message function formats errors correctly"""
    error_message = conn._error_message(error)
    assert error_message == expected_message


def test_network_connection_failure():
    # Match only the stable part of the error message across OS
    exp_err = rf"Error {ECONNREFUSED} connecting to localhost:9999\."
    with pytest.raises(ConnectionError, match=exp_err):
        redis = Redis(port=9999)
        redis.set("a", "b")


@pytest.mark.skipif(
    not hasattr(socket, "AF_UNIX"),
    reason="Unix domain sockets not supported on this platform",
)
def test_unix_socket_connection_failure():
    exp_err = "Error 2 connecting to unix:///tmp/a.sock. No such file or directory."
    with pytest.raises(ConnectionError, match=exp_err):
        redis = Redis(unix_socket_path="unix:///tmp/a.sock")
        redis.set("a", "b")


class TestUnitConnectionPool:
    @pytest.mark.parametrize(
        "max_conn", (-1, "str"), ids=("non-positive", "wrong type")
    )
    def test_throws_error_on_incorrect_max_connections(self, max_conn):
        with pytest.raises(
            ValueError, match='"max_connections" must be a positive integer'
        ):
            ConnectionPool(
                max_connections=max_conn,
            )

    def test_throws_error_on_cache_enable_in_resp2(self):
        with pytest.raises(
            RedisError, match="Client caching is only supported with RESP version 3"
        ):
            ConnectionPool(protocol=2, cache_config=CacheConfig())

    def test_throws_error_on_incorrect_cache_implementation(self):
        with pytest.raises(ValueError, match="Cache must implement CacheInterface"):
            ConnectionPool(protocol=3, cache="wrong")

    def test_returns_custom_cache_implementation(self, mock_cache):
        connection_pool = ConnectionPool(protocol=3, cache=mock_cache)

        assert mock_cache == connection_pool.cache
        connection_pool.disconnect()

    def test_creates_cache_with_custom_cache_factory(
        self, mock_cache_factory, mock_cache
    ):
        mock_cache_factory.get_cache.return_value = mock_cache

        connection_pool = ConnectionPool(
            protocol=3,
            cache_config=CacheConfig(max_size=5),
            cache_factory=mock_cache_factory,
        )

        assert connection_pool.cache == mock_cache
        connection_pool.disconnect()

    def test_creates_cache_with_given_configuration(self, mock_cache):
        connection_pool = ConnectionPool(
            protocol=3, cache_config=CacheConfig(max_size=100)
        )

        assert isinstance(connection_pool.cache, CacheInterface)
        assert connection_pool.cache.config.get_max_size() == 100
        assert isinstance(connection_pool.cache.eviction_policy, LRUPolicy)
        connection_pool.disconnect()

    def test_make_connection_proxy_connection_on_given_cache(self):
        connection_pool = ConnectionPool(protocol=3, cache_config=CacheConfig())

        assert isinstance(connection_pool.make_connection(), CacheProxyConnection)
        connection_pool.disconnect()


class TestUnitCacheProxyConnection:
    def test_clears_cache_on_disconnect(self, mock_connection, cache_conf):
        cache = DefaultCache(CacheConfig(max_size=10))
        cache_key = CacheKey(
            command="GET", redis_keys=("foo",), redis_args=("GET", "foo")
        )

        cache.set(
            CacheEntry(
                cache_key=cache_key,
                cache_value=b"bar",
                status=CacheEntryStatus.VALID,
                connection_ref=mock_connection,
            )
        )
        assert cache.get(cache_key).cache_value == b"bar"

        mock_connection.disconnect.return_value = None
        mock_connection.retry = "mock"
        mock_connection.host = "mock"
        mock_connection.port = "mock"
        mock_connection.credential_provider = UsernamePasswordCredentialProvider()

        proxy_connection = CacheProxyConnection(
            mock_connection, cache, threading.RLock()
        )
        proxy_connection.disconnect()

        assert len(cache.collection) == 0

    @pytest.mark.skipif(
        platform.python_implementation() == "PyPy",
        reason="Pypy doesn't support side_effect",
    )
    def test_read_response_returns_cached_reply(self, mock_cache, mock_connection):
        mock_connection.retry = "mock"
        mock_connection.host = "mock"
        mock_connection.port = "mock"
        mock_connection.credential_provider = UsernamePasswordCredentialProvider()

        mock_cache.is_cachable.return_value = True
        mock_cache.get.side_effect = [
            None,
            None,
            CacheEntry(
                cache_key=CacheKey(
                    command="GET", redis_keys=("foo",), redis_args=("GET", "foo")
                ),
                cache_value=CacheProxyConnection.DUMMY_CACHE_VALUE,
                status=CacheEntryStatus.IN_PROGRESS,
                connection_ref=mock_connection,
            ),
            CacheEntry(
                cache_key=CacheKey(
                    command="GET", redis_keys=("foo",), redis_args=("GET", "foo")
                ),
                cache_value=b"bar",
                status=CacheEntryStatus.VALID,
                connection_ref=mock_connection,
            ),
            CacheEntry(
                cache_key=CacheKey(
                    command="GET", redis_keys=("foo",), redis_args=("GET", "foo")
                ),
                cache_value=b"bar",
                status=CacheEntryStatus.VALID,
                connection_ref=mock_connection,
            ),
            CacheEntry(
                cache_key=CacheKey(
                    command="GET", redis_keys=("foo",), redis_args=("GET", "foo")
                ),
                cache_value=b"bar",
                status=CacheEntryStatus.VALID,
                connection_ref=mock_connection,
            ),
        ]
        mock_connection.send_command.return_value = Any
        mock_connection.read_response.return_value = b"bar"
        mock_connection.can_read.return_value = False

        proxy_connection = CacheProxyConnection(
            mock_connection, mock_cache, threading.RLock()
        )
        proxy_connection.send_command(*["GET", "foo"], **{"keys": ["foo"]})
        assert proxy_connection.read_response() == b"bar"
        assert proxy_connection._current_command_cache_key is None
        assert proxy_connection.read_response() == b"bar"

        mock_cache.set.assert_has_calls(
            [
                call(
                    CacheEntry(
                        cache_key=CacheKey(
                            command="GET",
                            redis_keys=("foo",),
                            redis_args=("GET", "foo"),
                        ),
                        cache_value=CacheProxyConnection.DUMMY_CACHE_VALUE,
                        status=CacheEntryStatus.IN_PROGRESS,
                        connection_ref=mock_connection,
                    )
                ),
                call(
                    CacheEntry(
                        cache_key=CacheKey(
                            command="GET",
                            redis_keys=("foo",),
                            redis_args=("GET", "foo"),
                        ),
                        cache_value=b"bar",
                        status=CacheEntryStatus.VALID,
                        connection_ref=mock_connection,
                    )
                ),
            ]
        )

        mock_cache.get.assert_has_calls(
            [
                call(
                    CacheKey(
                        command="GET", redis_keys=("foo",), redis_args=("GET", "foo")
                    )
                ),
                call(
                    CacheKey(
                        command="GET", redis_keys=("foo",), redis_args=("GET", "foo")
                    )
                ),
                call(
                    CacheKey(
                        command="GET", redis_keys=("foo",), redis_args=("GET", "foo")
                    )
                ),
            ]
        )

    @pytest.mark.skipif(
        platform.python_implementation() == "PyPy",
        reason="Pypy doesn't support side_effect",
    )
    def test_triggers_invalidation_processing_on_another_connection(
        self, mock_cache, mock_connection
    ):
        mock_connection.retry = "mock"
        mock_connection.host = "mock"
        mock_connection.port = "mock"
        mock_connection.credential_provider = UsernamePasswordCredentialProvider()

        another_conn = copy.deepcopy(mock_connection)
        another_conn.can_read.side_effect = [True, False]
        another_conn.read_response.return_value = None
        cache_entry = CacheEntry(
            cache_key=CacheKey(
                command="GET", redis_keys=("foo",), redis_args=("GET", "foo")
            ),
            cache_value=b"bar",
            status=CacheEntryStatus.VALID,
            connection_ref=another_conn,
        )
        mock_cache.is_cachable.return_value = True
        mock_cache.get.return_value = cache_entry
        mock_connection.can_read.return_value = False

        proxy_connection = CacheProxyConnection(
            mock_connection, mock_cache, threading.RLock()
        )
        proxy_connection.send_command(*["GET", "foo"], **{"keys": ["foo"]})

        assert proxy_connection.read_response() == b"bar"
        assert another_conn.can_read.call_count == 2
        another_conn.read_response.assert_called_once()
