feat: 完善日月食与月掩几何链路并扩展历法接口

- 新增日月食中心带、偏食带、阴影足迹、等时线、食分线及升落边界计算，支持极区与混合食拓扑 - 新增日食单时刻阴影求解器、站心状态查询、批量采样和 ΔT 覆盖接口 - 重构恒星与行星月掩路径，补充有限盘面接触、站心修正、掩带宽度、极区投影及升落边界 - 扩展 SVG 与 GeoJSON 输出，支持详细面板、全球/极区/地球投影、边界闭合、时间标记和拓扑签名 - 扩展日月食候选搜索、局地搜索、沙罗序列预计算与范围外推，补充系列锚点和成员一致性校验 - 补齐古历纪年、儒略历独有闰日、多公历候选、历法改革跨日及精确日期运算接口 - 优化 ΔT、章动、恒星时、月球地平线、事件根搜索和本地星历缓存，降低重复计算开销并提升边界稳定
2026-09-17 12:27:40 +08:00
parent 9ee2163cc7
commit 2bf8478639
428 changed files with 85981 additions and 7998 deletions
@@ -0,0 +1,100 @@
+package geojson_test
+
+import (
+	"encoding/json"
+	"math"
+	"testing"
+	"time"
+
+	"b612.me/astro/eclipse"
+	"b612.me/astro/geojson"
+	"b612.me/astro/internal/geodata"
+)
+
+func TestMarshalSolarEclipsePolarTwoLimitBandUsesSimpleFaces(t *testing.T) {
+	for _, sample := range []struct {
+		date        time.Time
+		centralStep time.Duration
+	}{
+		{time.Date(767, time.April, 3, 0, 0, 0, 0, time.UTC), 5 * time.Minute},
+		{time.Date(767, time.April, 3, 0, 0, 0, 0, time.UTC), time.Minute},
+		{time.Date(2981, time.October, 19, 0, 0, 0, 0, time.UTC), 5 * time.Minute},
+		{time.Date(2981, time.October, 19, 0, 0, 0, 0, time.UTC), time.Minute},
+	} {
+		t.Run(sample.date.Format("2006-01-02")+"/"+sample.centralStep.String(), func(t *testing.T) {
+			date := sample.date
+			partial, ok := eclipse.SolarEclipsePartialFootprints(date, eclipse.SolarEclipsePartialFootprintOptions{
+				Step: 5 * time.Minute, BoundaryPoints: 96, CentralShadowStep: 5 * time.Minute,
+				MagnitudeValues: []float64{0.2, 0.4, 0.6, 0.8, 1},
+			})
+			if !ok {
+				t.Fatal("expected solar eclipse footprints")
+			}
+			central, ok := eclipse.SolarEclipseCentralPath(date, eclipse.SolarEclipsePathOptions{
+				Step: sample.centralStep, TargetSpacingKM: 500,
+			})
+			if !ok {
+				t.Fatal("expected central path")
+			}
+			data, err := geojson.MarshalSolarEclipse(partial, &central)
+			if err != nil {
+				t.Fatalf("MarshalSolarEclipse: %v", err)
+			}
+			collection := decodeCollection(t, data)
+			band := featureWithRole(t, collection, "central-band")
+			assertClosedMultiPolygon(t, band)
+			var polygons [][][][]float64
+			if err := json.Unmarshal(band.Geometry.Coordinates, &polygons); err != nil {
+				t.Fatalf("decode central-band: %v", err)
+			}
+			if len(polygons) == 0 {
+				t.Fatal("polar central-band has no polygon")
+			}
+			for polygonIndex, polygon := range polygons {
+				if len(polygon) == 0 {
+					t.Fatalf("polygon %d has no exterior ring", polygonIndex)
+				}
+				ring := polygon[0]
+				for first := 0; first+1 < len(ring); first++ {
+					for second := first + 2; second+1 < len(ring); second++ {
+						if first == 0 && second+1 == len(ring)-1 {
+							continue
+						}
+						if polarAntimeridianFragmentEdge(ring[first], ring[first+1]) ||
+							polarAntimeridianFragmentEdge(ring[second], ring[second+1]) {
+							continue
+						}
+						if geoJSONSegmentsCross(ring[first], ring[first+1], ring[second], ring[second+1]) {
+							t.Fatalf("polygon %d self-intersects between edges %d and %d", polygonIndex, first, second)
+						}
+					}
+				}
+			}
+			rings := geoJSONMultiPolygonOuterRings(t, band)
+			paths := make([][]geodata.GeoPoint, 0, len(central.CenterLine))
+			for _, series := range [][]eclipse.SolarEclipsePathPoint{
+				central.NorthernLimit, central.SouthernLimit, central.CenterLine,
+			} {
+				for _, point := range series {
+					// Cross-section limits near the limb can have local greatest
+					// below the horizon; they are not visible-band witnesses.
+					local, ok := eclipse.GeometricLocalSolarEclipseOnDate(date, point.Longitude, point.Latitude, 0)
+					if ok && local.VisibleAtGreatest && local.Type != eclipse.SolarEclipsePartial {
+						paths = append(paths, []geodata.GeoPoint{{Longitude: point.Longitude, Latitude: point.Latitude}})
+					}
+				}
+			}
+			if len(paths) == 0 {
+				t.Fatal("missing independently verified visible witnesses")
+			}
+			if miss := geodata.SphericalPolygonsPathMissDistanceKM(rings, paths, false); miss > 2 {
+				t.Fatalf("central-band misses source path by %.3f km", miss)
+			}
+		})
+	}
+}
+
+func polarAntimeridianFragmentEdge(first, second []float64) bool {
+	return len(first) >= 2 && len(second) >= 2 &&
+		(math.Abs(first[0]) == 180 || math.Abs(second[0]) == 180)
+}