import asyncio
import json
import smtplib
from unittest.mock import AsyncMock, MagicMock

import allure
import pytest

import src.messaging.rabbitmq_client as rabbitmq_client_module
from src.messaging.consumers.consumers import ResetEmailConsumer, WelcomeEmailConsumer
from src.messaging.rabbitmq_client import RabbitMQClient


@pytest.mark.unit
class TestRabbitMQClient:

    @pytest.mark.parametrize("",[
        pytest.param(id="Connect_retries_then_succeeds")
    ])
    async def test_connect_retries_then_succeeds(self, monkeypatch):
        
        with allure.step("Mocking connection to the rabbitmq"):
            fake_connection = MagicMock()
            fake_connection.is_closed = False
            fake_connection.channel = AsyncMock(return_value=MagicMock())
            
            mock_connect = AsyncMock(
                side_effect=[ConnectionError(), ConnectionError(), fake_connection]
            )
            monkeypatch.setattr(rabbitmq_client_module.aio_pika, "connect_robust", mock_connect)
            monkeypatch.setattr(asyncio, "sleep", AsyncMock())  # чтобы не ждать реально

        with allure.step("Test client connection"):
            client = RabbitMQClient()
            await client.connect()

            assert mock_connect.await_count == 3
            assert client.connection is fake_connection


    @pytest.mark.parametrize("",[
        pytest.param(id="test_connect_gives_up_after_5_attempts")
    ])
    async def test_connect_gives_up_after_5_attempts(self, monkeypatch):
        
        with allure.step("Mocking connection to the rabbitmq"):
            mock_connect = AsyncMock(side_effect=ConnectionError("still down"))
            monkeypatch.setattr(rabbitmq_client_module.aio_pika, "connect_robust", mock_connect)
            monkeypatch.setattr(asyncio, "sleep", AsyncMock())

        with allure.step("Test client connection"):
            client = RabbitMQClient()

        with pytest.raises(ConnectionError):
            await client.connect()

        assert mock_connect.await_count == 5


    @pytest.mark.parametrize("",[
        pytest.param(id="test_get_channel_negative")
    ])
    async def test_get_channel_negative(self, monkeypatch)->None:
        
        with allure.step("Mocking connection to the rabbitmq"):
            fake_connection = MagicMock()
            fake_connection.is_closed = False
            fake_connection.channel = AsyncMock(return_value=None)
        
            mock_connect = AsyncMock(return_value=fake_connection)
            monkeypatch.setattr(rabbitmq_client_module.aio_pika, "connect_robust", mock_connect)
            
        with allure.step("Test client connection"):
            client = RabbitMQClient()
            
        with pytest.raises(RuntimeError):
            await client.get_channel()


    @pytest.mark.parametrize("",[
        pytest.param(id="test_get_channel_positive")
    ])
    async def test_get_channel_positive(self, monkeypatch)->None:
        
        with allure.step("Mocking connection to the rabbitmq"):
            
            fake_connection = MagicMock()
            fake_connection.is_closed = False
            fake_connection.channel = AsyncMock(return_value=MagicMock())
            
            mock_connect = AsyncMock(return_value=fake_connection)
            monkeypatch.setattr(rabbitmq_client_module.aio_pika, "connect_robust", mock_connect)
            
        with allure.step("Test client connection"):
            client = RabbitMQClient()
            await client.get_channel()
        
        assert client.channel is fake_connection.channel.return_value
    
def make_fake_message(body: dict, routing_key: str = "email.welcome") -> MagicMock:
    """Строим 'фальшивое' RabbitMQ-сообщение вручную, без реального брокера."""
    message = MagicMock()
    message.body = json.dumps(body).encode()
    message.routing_key = routing_key
    message.nack = AsyncMock()  # запоминает, вызвали ли nack и с какими аргументами

    # message.process(...) в реальном aio_pika — async context manager,
    # поэтому нужен объект с асинхронными __aenter__/__aexit__.
    process_cm = MagicMock()
    process_cm.__aenter__ = AsyncMock(return_value=None)
    process_cm.__aexit__ = AsyncMock(return_value=False)
    message.process = MagicMock(return_value=process_cm)
    return message


@pytest.mark.unit
class TestEmailConsumers:
    
    @pytest.mark.parametrize("",[
        pytest.param(id="test_start_consuming_negative")
    ])
    async def test_start_consuming_negative(self, monkeypatch)->None:
        
        with allure.step("Mocking connection to the rabbitmq"):
            consumer = WelcomeEmailConsumer()
            consumer.setup=AsyncMock()
            
        with allure.step("Test client connection"), pytest.raises(RuntimeError):
            await consumer.start_consuming()
        
        
    @pytest.mark.parametrize("error", [
        pytest.param(smtplib.SMTPServerDisconnected(), id="smtplib.SMTPServerDisconnected"),
        pytest.param(smtplib.SMTPConnectError(421, "Service not available"), id="smtplib.SMTPConnectError"),
        pytest.param(TimeoutError(), id="TimeoutError"),
        pytest.param(ConnectionRefusedError(), id="ConnectionRefusedError"),
    ])
    async def test_process_message_transient_errors_requeue(self, error) -> None:
        consumer = WelcomeEmailConsumer()
        consumer.daemon.send_email = AsyncMock(side_effect=error)

        message = make_fake_message({"email": "user@example.com"})
        await consumer.process_message(message)

        message.nack.assert_awaited_once_with(requeue=True)


    @pytest.mark.parametrize("",[
        pytest.param(id="test_process_message_positive")
    ])
    async def test_process_message_positive(self) -> None:

        with allure.step("Mocking dependencies"):
            consumer = WelcomeEmailConsumer()
            consumer.daemon.send_email = AsyncMock()

        with allure.step("Test process_message"):
            message = make_fake_message({"email": "user@example.com"})
            await consumer.process_message(message)

        consumer.daemon.send_email.assert_awaited_once_with("user@example.com")
        message.nack.assert_not_called()


@pytest.mark.unit
class TestResetEmailConsumer:

    @pytest.mark.parametrize("",[
        pytest.param(id="test_reset_start_consuming_negative")
    ])
    async def test_start_consuming_negative(self, monkeypatch) -> None:

        with allure.step("Mocking connection to the rabbitmq"):
            consumer = ResetEmailConsumer()
            consumer.setup = AsyncMock()

        with allure.step("Test client connection"), pytest.raises(RuntimeError):
            await consumer.start_consuming()


    @pytest.mark.parametrize("error", [
        pytest.param(smtplib.SMTPServerDisconnected(), id="smtplib.SMTPServerDisconnected"),
        pytest.param(smtplib.SMTPConnectError(421, "Service not available"), id="smtplib.SMTPConnectError"),
        pytest.param(TimeoutError(), id="TimeoutError"),
        pytest.param(ConnectionRefusedError(), id="ConnectionRefusedError"),
    ])
    async def test_process_message_transient_errors_requeue(self, error) -> None:
        consumer = ResetEmailConsumer()
        consumer.daemon.send_email = AsyncMock(side_effect=error)

        message = make_fake_message(
            {"email": "user@example.com", "temp_password": "Temp1234!"},
            routing_key="email.reset",
        )
        await consumer.process_message(message)

        message.nack.assert_awaited_once_with(requeue=True)


    @pytest.mark.parametrize("",[
        pytest.param(id="test_reset_process_message_permanent_error_goes_to_dlq")
    ])
    async def test_process_message_permanent_error_goes_to_dlq(self) -> None:
        consumer = ResetEmailConsumer()
        consumer.daemon.send_email = AsyncMock(side_effect=ValueError("bad payload"))

        message = make_fake_message(
            {"email": "user@example.com", "temp_password": "Temp1234!"},
            routing_key="email.reset",
        )
        await consumer.process_message(message)

        message.nack.assert_awaited_once_with(requeue=False)


    @pytest.mark.parametrize("",[
        pytest.param(id="test_reset_process_message_positive")
    ])
    async def test_process_message_positive(self) -> None:

        with allure.step("Mocking dependencies"):
            consumer = ResetEmailConsumer()
            consumer.daemon.send_email = AsyncMock()

        with allure.step("Test process_message"):
            message = make_fake_message(
                {"email": "user@example.com", "temp_password": "Temp1234!"},
                routing_key="email.reset",
            )
            await consumer.process_message(message)

        consumer.daemon.send_email.assert_awaited_once_with("user@example.com", "Temp1234!")
        message.nack.assert_not_called()