"""tests/test_analysis.py —— 空间分析单元测试。"""

import pytest
import geopandas as gpd
from shapely.geometry import Point, Polygon

from geo_tools.analysis.spatial_ops import overlay, select_by_location
from geo_tools.analysis.stats import area_weighted_mean, count_by_polygon, summarize_attributes


class TestOverlay:
    def test_intersection(self, sample_multi_polygon_gdf):
        poly_a = sample_multi_polygon_gdf.iloc[[0]].copy()
        poly_b = sample_multi_polygon_gdf.iloc[[1]].copy()
        result = overlay(poly_a, poly_b, how="intersection")
        assert len(result) >= 1
        assert result.geometry.is_valid.all()

    def test_union(self, sample_multi_polygon_gdf):
        poly_a = sample_multi_polygon_gdf.iloc[[0]].copy()
        poly_b = sample_multi_polygon_gdf.iloc[[1]].copy()
        result = overlay(poly_a, poly_b, how="union", keep_geom_type=False)
        assert result.geometry.is_valid.all()


class TestSelectByLocation:
    def test_select_points_in_polygon(self, sample_points_gdf, sample_polygon_gdf):
        # polygon 覆盖华北区，应选中 北京 点
        result = select_by_location(sample_points_gdf, sample_polygon_gdf, predicate="intersects")
        assert len(result) >= 1

    def test_select_within(self, sample_points_gdf, sample_polygon_gdf):
        result = select_by_location(sample_points_gdf, sample_polygon_gdf, predicate="within")
        assert len(result) >= 0  # 可能有点在边界上


class TestAreaWeightedMean:
    def test_global_weighted_mean(self, sample_multi_polygon_gdf):
        result = area_weighted_mean(sample_multi_polygon_gdf, value_col="value")
        assert "area_weighted_mean" in result.index
        assert result["area_weighted_mean"] > 0

    def test_grouped_weighted_mean(self, sample_multi_polygon_gdf):
        gdf = sample_multi_polygon_gdf.copy()
        gdf["group"] = ["A", "B"]
        result = area_weighted_mean(gdf, value_col="value", group_col="group")
        assert "area_weighted_mean" in result.columns
        assert len(result) == 2


class TestSummarizeAttributes:
    def test_basic_summary(self, sample_points_gdf):
        result = summarize_attributes(sample_points_gdf, columns=["value"])
        assert "column" in result.columns
        assert "mean" in result.columns

    def test_grouped_summary(self, sample_points_gdf):
        gdf = sample_points_gdf.copy()
        gdf["group"] = ["北方", "东部", "南方"]
        result = summarize_attributes(gdf, columns=["value"], group_col="group")
        # 每组一行
        assert len(result) == 3


class TestCountByPolygon:
    def test_count_points_in_polygons(self, sample_points_gdf, sample_polygon_gdf):
        result = count_by_polygon(sample_points_gdf, sample_polygon_gdf)
        assert "point_count" in result.columns
        assert result["point_count"].dtype.kind == "i"  # 整数

    def test_polygon_with_no_points(self):
        # 南海中的 polygon，不含任何点
        poly = Polygon([(115, 10), (120, 10), (120, 15), (115, 15)])
        polygons = gpd.GeoDataFrame({"id": [1]}, geometry=[poly], crs="EPSG:4326")
        points = gpd.GeoDataFrame(
            geometry=[Point(116.4, 39.9)],  # 北京，不在 polygon 内
            crs="EPSG:4326",
        )
        result = count_by_polygon(points, polygons)
        assert result["point_count"].iloc[0] == 0