import uuid
from datetime import UTC, datetime
from unittest.mock import AsyncMock, MagicMock, patch

import pytest
import pytest_asyncio
from httpx import ASGITransport, AsyncClient
from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
from sqlalchemy.pool import StaticPool

from app.database import Base
from app.main import app
from app.models.user import User
from app.api.deps import get_current_user, get_db
from app.services.auth import hash_password
from app.services.ai_engine.base import AIQueryResult, EngineType


@pytest_asyncio.fixture
async def async_engine():
    engine = create_async_engine(
        "sqlite+aiosqlite:///:memory:",
        connect_args={"check_same_thread": False},
        poolclass=StaticPool,
    )
    async with engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)
    yield engine
    await engine.dispose()


@pytest_asyncio.fixture
async def async_session(async_engine):
    async_session_maker = async_sessionmaker(
        async_engine,
        class_=AsyncSession,
        expire_on_commit=False,
        autoflush=False,
        autocommit=False,
    )
    async with async_session_maker() as session:
        yield session


@pytest_asyncio.fixture
async def test_user(async_session):
    user = User(
        id=uuid.uuid4(),
        email="test@example.com",
        password_hash=hash_password("Test@123456"),
        name="Test User",
        plan="free",
        max_queries=5,
        is_active=True,
        email_verified=True,
    )
    async_session.add(user)
    await async_session.commit()
    await async_session.refresh(user)
    return user


@pytest_asyncio.fixture
async def async_client(async_session, test_user):
    async def override_get_db():
        yield async_session

    async def override_get_current_user():
        return test_user

    app.dependency_overrides[get_db] = override_get_db
    app.dependency_overrides[get_current_user] = override_get_current_user

    transport = ASGITransport(app=app)
    async with AsyncClient(transport=transport, base_url="http://test") as client:
        yield client

    app.dependency_overrides.clear()


def _make_result(
    engine_type: EngineType,
    query: str = "best insurance",
    has_brand: bool = False,
    has_competitor: bool = False,
) -> AIQueryResult:
    return AIQueryResult(
        engine_type=engine_type,
        query=query,
        raw_response="BrandX is a great insurance company",
        citations=[],
        has_brand_citation=has_brand,
        has_competitor_citation=has_competitor,
        brand_context="BrandX is great" if has_brand else None,
        competitor_contexts=["CompY is ok"] if has_competitor else [],
        response_time_ms=150,
        timestamp=datetime.now(UTC),
    )


class TestSingleQueryEndpoint:
    @pytest.mark.asyncio
    async def test_query_single_engine(self, async_client):
        mock_result = _make_result(EngineType.CHATGPT, has_brand=True)
        with patch("app.api.ai_engines.get_batch_service") as mock_get_service:
            mock_service = AsyncMock()
            mock_service.query_single.return_value = mock_result
            mock_get_service.return_value = mock_service

            response = await async_client.post(
                "/api/v1/ai-engines/query",
                json={
                    "engine": "chatgpt",
                    "query": "best insurance",
                    "brand_name": "BrandX",
                    "competitor_names": ["CompY"],
                },
            )

        assert response.status_code == 200
        data = response.json()
        assert data["engine_type"] == "chatgpt"
        assert data["has_brand_citation"] is True
        assert data["query"] == "best insurance"


class TestBatchQueryEndpoint:
    @pytest.mark.asyncio
    async def test_query_batch_parallel(self, async_client):
        r1 = _make_result(EngineType.CHATGPT, has_brand=True)
        r2 = _make_result(EngineType.PERPLEXITY, has_brand=False, has_competitor=True)
        with patch("app.api.ai_engines.get_batch_service") as mock_get_service:
            mock_service = AsyncMock()
            mock_service.query_batch.return_value = [r1, r2]
            mock_service.calculate_citation_rate = MagicMock(return_value={
                "total_engines": 2,
                "brand_citation_count": 1,
                "brand_citation_rate": 0.5,
                "competitor_citation_count": 1,
                "competitor_citation_rate": 0.5,
            })
            mock_get_service.return_value = mock_service

            response = await async_client.post(
                "/api/v1/ai-engines/query-batch",
                json={
                    "engines": ["chatgpt", "perplexity"],
                    "query": "best insurance",
                    "brand_name": "BrandX",
                    "competitor_names": ["CompY"],
                },
            )

        assert response.status_code == 200
        data = response.json()
        assert "results" in data
        assert "citation_rate" in data
        assert len(data["results"]) == 2
        assert data["citation_rate"]["brand_citation_rate"] == 0.5


class TestGetResultsEndpoint:
    @pytest.mark.asyncio
    async def test_get_results(self, async_client):
        r1 = _make_result(EngineType.CHATGPT, has_brand=True)
        r2 = _make_result(EngineType.KIMI, has_brand=False)
        with patch("app.api.ai_engines.get_batch_service") as mock_get_service:
            mock_service = AsyncMock()
            mock_service.query_batch.return_value = [r1, r2]
            mock_service.calculate_citation_rate = MagicMock(return_value={
                "total_engines": 2,
                "brand_citation_count": 1,
                "brand_citation_rate": 0.5,
                "competitor_citation_count": 0,
                "competitor_citation_rate": 0.0,
            })
            mock_get_service.return_value = mock_service

            response = await async_client.get(
                "/api/v1/ai-engines/results",
                params={
                    "engines": "chatgpt,kimi",
                    "query": "best insurance",
                    "brand_name": "BrandX",
                },
            )

        assert response.status_code == 200
        data = response.json()
        assert "results" in data
        assert "citation_rate" in data


class TestUnauthorizedAccess:
    @pytest.mark.asyncio
    async def test_unauthorized_returns_401(self, async_session):
        async def override_get_db():
            yield async_session

        app.dependency_overrides[get_db] = override_get_db

        transport = ASGITransport(app=app)
        async with AsyncClient(transport=transport, base_url="http://test") as client:
            headers = {"Authorization": "Bearer invalid_token"}
            response = await client.post(
                "/api/v1/ai-engines/query",
                json={
                    "engine": "chatgpt",
                    "query": "test",
                    "brand_name": "BrandX",
                },
                headers=headers,
            )
            assert response.status_code == 401

        app.dependency_overrides.clear()