"""LocalFactorEvaluator 单元测试。

使用 MagicMock 模拟 FactorEngine，避免依赖真实数据库。
"""

from unittest.mock import MagicMock, patch

import numpy as np
import polars as pl
import pytest

from src.factorminer.evaluation.local_engine import LocalFactorEvaluator


@pytest.fixture
def mock_engine():
    """提供 mock 的 FactorEngine 实例。"""
    with patch("src.factorminer.evaluation.local_engine.FactorEngine") as mock_cls:
        instance = MagicMock()
        mock_cls.return_value = instance
        yield instance


def test_evaluate_single(mock_engine):
    """测试单个因子计算并正确 pivot 为矩阵。"""
    mock_engine.compute.return_value = pl.DataFrame(
        {
            "ts_code": ["000001.SZ", "000001.SZ", "000002.SZ", "000002.SZ"],
            "trade_date": ["20240101", "20240102", "20240101", "20240102"],
            "alpha": [1.0, 2.0, 3.0, 4.0],
        }
    )
    evaluator = LocalFactorEvaluator("20240101", "20240102")
    result = evaluator.evaluate_single("alpha", "cs_rank(close)")

    mock_engine.add_factor.assert_called_once_with("alpha", "cs_rank(close)")
    mock_engine.compute.assert_called_once_with(["alpha"], "20240101", "20240102", None)
    mock_engine.clear.assert_called_once()

    assert result.shape == (2, 2)
    np.testing.assert_array_equal(
        result,
        np.array([[1.0, 2.0], [3.0, 4.0]], dtype=np.float64),
    )


def test_evaluate_empty_specs(mock_engine):
    """测试空 specs 直接返回空字典。"""
    evaluator = LocalFactorEvaluator("20240101", "20240102")
    result = evaluator.evaluate([])
    assert result == {}
    mock_engine.compute.assert_not_called()


def test_evaluate_batch(mock_engine):
    """测试批量计算多个因子。"""
    mock_engine.compute.return_value = pl.DataFrame(
        {
            "ts_code": ["000001.SZ", "000001.SZ", "000002.SZ", "000002.SZ"],
            "trade_date": ["20240101", "20240102", "20240101", "20240102"],
            "alpha1": [1.0, 2.0, 3.0, 4.0],
            "alpha2": [5.0, 6.0, 7.0, 8.0],
        }
    )
    evaluator = LocalFactorEvaluator("20240101", "20240102")
    result = evaluator.evaluate(
        [
            ("alpha1", "cs_rank(close)"),
            ("alpha2", "cs_rank(vol)"),
        ]
    )

    assert set(result.keys()) == {"alpha1", "alpha2"}
    np.testing.assert_array_equal(
        result["alpha1"],
        np.array([[1.0, 2.0], [3.0, 4.0]], dtype=np.float64),
    )
    np.testing.assert_array_equal(
        result["alpha2"],
        np.array([[5.0, 6.0], [7.0, 8.0]], dtype=np.float64),
    )
    mock_engine.clear.assert_called_once()


def test_evaluate_returns(mock_engine):
    """测试收益率矩阵计算。"""
    mock_engine.compute.return_value = pl.DataFrame(
        {
            "ts_code": ["000001.SZ", "000001.SZ", "000002.SZ", "000002.SZ"],
            "trade_date": ["20240101", "20240102", "20240101", "20240102"],
            "__returns": [0.01, 0.02, -0.01, 0.03],
        }
    )
    evaluator = LocalFactorEvaluator("20240101", "20240102")
    result = evaluator.evaluate_returns(periods=5)

    mock_engine.add_factor.assert_called_once_with(
        "__returns", "ts_pct_change(close, 5)"
    )
    assert result.shape == (2, 2)
    np.testing.assert_array_equal(
        result,
        np.array([[0.01, 0.02], [-0.01, 0.03]], dtype=np.float64),
    )
    mock_engine.clear.assert_called_once()


def test_evaluate_with_nan(mock_engine):
    """测试缺失值正确填充为 np.nan。"""
    mock_engine.compute.return_value = pl.DataFrame(
        {
            "ts_code": ["000001.SZ", "000001.SZ", "000002.SZ"],
            "trade_date": ["20240101", "20240102", "20240101"],
            "alpha": [1.0, 2.0, 3.0],
        }
    )
    evaluator = LocalFactorEvaluator("20240101", "20240102")
    result = evaluator.evaluate_single("alpha", "cs_rank(close)")

    assert result.shape == (2, 2)
    assert np.isnan(result[1, 1])
    assert result[0, 0] == 1.0
    assert result[0, 1] == 2.0
    assert result[1, 0] == 3.0


def test_stock_codes_filter(mock_engine):
    """测试传入股票代码列表时正确透传给 FactorEngine。"""
    mock_engine.compute.return_value = pl.DataFrame(
        {
            "ts_code": ["000001.SZ", "000001.SZ"],
            "trade_date": ["20240101", "20240102"],
            "alpha": [1.0, 2.0],
        }
    )
    evaluator = LocalFactorEvaluator("20240101", "20240102", stock_codes=["000001.SZ"])
    result = evaluator.evaluate_single("alpha", "close")

    mock_engine.compute.assert_called_once_with(
        ["alpha"], "20240101", "20240102", ["000001.SZ"]
    )
    assert result.shape == (1, 2)


def test_to_matrix_missing_factor_column(mock_engine):
    """测试 DataFrame 缺少目标因子列时抛出 ValueError。"""
    mock_engine.compute.return_value = pl.DataFrame(
        {
            "ts_code": ["000001.SZ"],
            "trade_date": ["20240101"],
        }
    )
    evaluator = LocalFactorEvaluator("20240101", "20240102")
    with pytest.raises(ValueError, match="未找到因子列 'alpha'"):
        evaluator.evaluate_single("alpha", "close")