import pytest
from unittest.mock import patch, AsyncMock, MagicMock
from httpx import AsyncClient, ASGITransport
from sqlalchemy.exc import SQLAlchemyError

from app.main import app
from app.models import KolVideo
from app.api.v1.export import set_export_data, get_export_data


class TestErrorHandling:
    """Tests for error handling scenarios."""

    @pytest.fixture
    async def client(self, override_get_db):
        """Create test client with dependency override."""
        transport = ASGITransport(app=app)
        async with AsyncClient(transport=transport, base_url="http://test") as ac:
            yield ac

    @pytest.fixture
    async def seed_data(self, test_session, sample_video_data):
        """Seed test data."""
        data = sample_video_data.copy()
        data["item_id"] = "error_test_001"
        data["star_id"] = "error_star_001"
        video = KolVideo(**data)
        test_session.add(video)
        await test_session.commit()
        return video

    # Query API error handling tests

    @patch("app.api.v1.query.query_videos")
    @patch("app.api.v1.query.get_brand_names", new_callable=AsyncMock)
    async def test_query_database_error(
        self, mock_brand, mock_query, client
    ):
        """Test query returns error on database failure."""
        mock_brand.return_value = {}
        mock_query.side_effect = SQLAlchemyError("Database connection failed")

        response = await client.post(
            "/api/v1/query",
            json={"type": "star_id", "values": ["test_id"]},
        )
        assert response.status_code == 200
        data = response.json()
        assert data["success"] is False
        assert "数据库连接失败" in data["error"]

    @patch("app.api.v1.query.get_brand_names", new_callable=AsyncMock)
    async def test_query_brand_api_failure_fallback(
        self, mock_brand, client, test_session, seed_data
    ):
        """Test query continues with fallback when brand API fails."""
        mock_brand.side_effect = Exception("Brand API timeout")

        response = await client.post(
            "/api/v1/query",
            json={"type": "star_id", "values": ["error_star_001"]},
        )
        assert response.status_code == 200
        data = response.json()
        # Should still succeed, brand name falls back to brand_id
        assert data["success"] is True
        assert data["total"] >= 0

    @patch("app.api.v1.query.query_videos")
    @patch("app.api.v1.query.get_brand_names", new_callable=AsyncMock)
    async def test_query_generic_error(
        self, mock_brand, mock_query, client
    ):
        """Test query returns error on unexpected exception."""
        mock_brand.return_value = {}
        mock_query.side_effect = Exception("Unexpected error")

        response = await client.post(
            "/api/v1/query",
            json={"type": "star_id", "values": ["test_id"]},
        )
        assert response.status_code == 200
        data = response.json()
        assert data["success"] is False
        assert "Unexpected error" in data["error"]

    # Export API error handling tests

    async def test_export_no_data_error(self, client):
        """Test export returns error when no data is cached."""
        # Clear cached data
        set_export_data([])

        response = await client.get("/api/v1/export?format=xlsx")
        assert response.status_code == 400
        data = response.json()
        assert data["success"] is False
        assert "无数据可导出" in data["error"]

    async def test_export_with_data_success(self, client, sample_video_data):
        """Test export succeeds when data is cached."""
        # Set cached data
        set_export_data([sample_video_data])

        response = await client.get("/api/v1/export?format=xlsx")
        assert response.status_code == 200
        assert "application/vnd.openxmlformats" in response.headers["content-type"]

    async def test_export_csv_with_data_success(self, client, sample_video_data):
        """Test CSV export succeeds when data is cached."""
        set_export_data([sample_video_data])

        response = await client.get("/api/v1/export?format=csv")
        assert response.status_code == 200
        assert "text/csv" in response.headers["content-type"]

    @patch("app.api.v1.export.generate_excel")
    async def test_export_generation_error(
        self, mock_generate, client, sample_video_data
    ):
        """Test export returns error when file generation fails."""
        mock_generate.side_effect = Exception("Excel generation failed")
        set_export_data([sample_video_data])

        response = await client.get("/api/v1/export?format=xlsx")
        assert response.status_code == 500
        data = response.json()
        assert data["success"] is False
        assert "导出失败" in data["error"]

    # Input validation tests

    async def test_query_validation_empty_values(self, client):
        """Test query returns 422 for empty values."""
        response = await client.post(
            "/api/v1/query",
            json={"type": "star_id", "values": []},
        )
        assert response.status_code == 422

    async def test_query_validation_invalid_type(self, client):
        """Test query returns 422 for invalid query type."""
        response = await client.post(
            "/api/v1/query",
            json={"type": "invalid_type", "values": ["test"]},
        )
        assert response.status_code == 422

    async def test_query_validation_missing_type(self, client):
        """Test query returns 422 for missing type field."""
        response = await client.post(
            "/api/v1/query",
            json={"values": ["test"]},
        )
        assert response.status_code == 422

    async def test_query_validation_missing_values(self, client):
        """Test query returns 422 for missing values field."""
        response = await client.post(
            "/api/v1/query",
            json={"type": "star_id"},
        )
        assert response.status_code == 422