feat: 完善时标与天象几何计算并扩展输出接口

- 新增时标、ΔT 模型、质心时间与 UT1 支持 - 改进日月食、月掩、行星事件及路径边界计算 - 完善恒星三维自行与动态距离传播 - 扩展 SVG、GeoJSON、KML 输出与底层距离换算工具 - 整理中英文手册、示例资源及回归测试
2026-09-23 18:55:12 +08:00
parent 1f31a9b5b5
commit 16c62a97d5
503 changed files with 33290 additions and 9471 deletions
@@ -0,0 +1,176 @@
+package svg
+
+import (
+	"encoding/xml"
+	"io"
+	"math"
+	"strconv"
+	"strings"
+	"testing"
+	"time"
+
+	"b612.me/astro/internal/svgchart"
+)
+
+// 本地月掩页脚契约：方向说明与补充说明（含时标声明）都排在可用宽度内，同一块各行宽度接近，
+// 不留孤立短尾行，且显示时区的偏移只写一次。
+
+const (
+	localOccultationFooterDirectionFill = "#4f595b"
+	localOccultationFooterNoteFill      = "#747c7d"
+)
+
+type localOccultationFooterText struct {
+	fill     string
+	fontSize float64
+	value    string
+}
+
+func localOccultationFooterTexts(t *testing.T, diagram string) []localOccultationFooterText {
+	t.Helper()
+	decoder := xml.NewDecoder(strings.NewReader(diagram))
+	texts := []localOccultationFooterText{}
+	for {
+		token, err := decoder.Token()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			t.Fatalf("decode SVG: %v", err)
+		}
+		element, ok := token.(xml.StartElement)
+		if !ok || element.Name.Local != "text" {
+			continue
+		}
+		text := localOccultationFooterText{}
+		for _, attribute := range element.Attr {
+			switch attribute.Name.Local {
+			case "fill":
+				text.fill = attribute.Value
+			case "font-size":
+				text.fontSize, _ = strconv.ParseFloat(attribute.Value, 64)
+			}
+		}
+		if text.fill != localOccultationFooterDirectionFill && text.fill != localOccultationFooterNoteFill {
+			continue
+		}
+		var content string
+		if err := decoder.DecodeElement(&content, &element); err != nil {
+			t.Fatalf("decode text element: %v", err)
+		}
+		text.value = content
+		texts = append(texts, text)
+	}
+	return texts
+}
+
+func localOccultationFooterWidths(lines []localOccultationFooterText) ([]string, []float64) {
+	values := make([]string, 0, len(lines))
+	widths := make([]float64, 0, len(lines))
+	for _, line := range lines {
+		values = append(values, line.value)
+		widths = append(widths, svgchart.EstimatedTextWidth(line.value, line.fontSize))
+	}
+	return values, widths
+}
+
+func localOccultationFooterSpread(lines []localOccultationFooterText) float64 {
+	_, widths := localOccultationFooterWidths(lines)
+	minimum, maximum := widths[0], widths[0]
+	for _, width := range widths {
+		minimum = math.Min(minimum, width)
+		maximum = math.Max(maximum, width)
+	}
+	return maximum / minimum
+}
+
+func localOccultationFooterGroup(lines []localOccultationFooterText, fill string) []localOccultationFooterText {
+	group := []localOccultationFooterText{}
+	for _, line := range lines {
+		if line.fill == fill {
+			group = append(group, line)
+		}
+	}
+	return group
+}
+
+// 说明块各行的最大最小宽度比不得超过 15%，整块最短行不得短于最长行的 60%（旧实现里时标声明独占的短尾行只有 25%~47%）。
+func TestLocalOccultationFooterLinesAreEven(t *testing.T) {
+	location := time.FixedZone("UTC+08:00", 8*3600)
+	const width, height = 920, 720
+	for _, language := range []string{"zh", "en"} {
+		star, err := LocalStarOccultationSVG(localHR4799Occultation(t), hr4799StarCoordinate(), LocalStarOccultationSVGOptions{
+			Language: language, Location: location, Width: width, Height: height,
+		})
+		if err != nil {
+			t.Fatalf("star %s: %v", language, err)
+		}
+		planet, err := LocalPlanetOccultationSVG(localSaturnOccultation(t), LocalPlanetOccultationSVGOptions{
+			Language: language, Location: location, Width: width, Height: height,
+		})
+		if err != nil {
+			t.Fatalf("planet %s: %v", language, err)
+		}
+		for name, diagram := range map[string]string{"star": star, "planet": planet} {
+			lines := localOccultationFooterTexts(t, diagram)
+			if len(lines) < 2 {
+				t.Fatalf("%s %s: footer lines = %#v, want the direction and note blocks", name, language, lines)
+			}
+			values, widths := localOccultationFooterWidths(lines)
+			for index, line := range lines {
+				if limit := float64(width) - 80; widths[index] > limit {
+					t.Fatalf("%s %s: footer line %q width %.1f exceeds %.1f", name, language, line.value, widths[index], limit)
+				}
+				if strings.Contains(line.value, "…") {
+					t.Fatalf("%s %s: default footer text is truncated: %q", name, language, line.value)
+				}
+			}
+			note := localOccultationFooterGroup(lines, localOccultationFooterNoteFill)
+			if len(note) == 0 {
+				t.Fatalf("%s %s: missing the footer note block", name, language)
+			}
+			// 说明块与方向说明行字号不同（fs9 / fs10），故按块判 1.15；整块只兜"孤尾短行"（1.60）。
+			if spread := localOccultationFooterSpread(note); spread > 1.15 {
+				t.Fatalf("%s %s: note block spread = %.3f, want <= 1.15 (%q)", name, language, spread, values)
+			}
+			if spread := localOccultationFooterSpread(lines); spread > 1.60 {
+				t.Fatalf("%s %s: footer spread = %.3f, want no orphan short line (%q)", name, language, spread, values)
+			}
+			joined := strings.Join(values, " ")
+			if zone := "显示时区"; language == "en" {
+				if !strings.Contains(joined, "shown in") {
+					t.Fatalf("%s %s: footer note lost the time zone declaration: %q", name, language, joined)
+				}
+			} else if !strings.Contains(joined, zone) {
+				t.Fatalf("%s %s: footer note lost the time zone declaration: %q", name, language, joined)
+			}
+		}
+	}
+}
+
+// 偏移型时区名（UTC+08:00）不得让时标声明写成“显示时区 UTC+08:00，UTC+08:00”。
+func TestLocalOccultationFooterNamesTheZoneOnce(t *testing.T) {
+	location := time.FixedZone("UTC+08:00", 8*3600)
+	for _, language := range []string{"zh", "en"} {
+		star, err := LocalStarOccultationSVG(localHR4799Occultation(t), hr4799StarCoordinate(), LocalStarOccultationSVGOptions{
+			Language: language, Location: location,
+		})
+		if err != nil {
+			t.Fatalf("star %s: %v", language, err)
+		}
+		planet, err := LocalPlanetOccultationSVG(localSaturnOccultation(t), LocalPlanetOccultationSVGOptions{
+			Language: language, Location: location,
+		})
+		if err != nil {
+			t.Fatalf("planet %s: %v", language, err)
+		}
+		for name, diagram := range map[string]string{"star": star, "planet": planet} {
+			note := localOccultationFooterGroup(localOccultationFooterTexts(t, diagram), localOccultationFooterNoteFill)
+			values, _ := localOccultationFooterWidths(note)
+			joined := strings.Join(values, " ")
+			if got := strings.Count(joined, "UTC+08:00"); got != 1 {
+				t.Fatalf("%s %s: footer note names UTC+08:00 %d times, want once: %q", name, language, got, joined)
+			}
+		}
+	}
+}