- fix: Correct sun.TrueBo calculation, now using basic.HSunTrueBo for correct solar latitude

- fix: Rename GetSunDownTime to GetSunSetTime in basic/sun.go and update related calls/outputs
- fix: Update test cases to use new method and error constant names

- improve: Rename all DownTime/Down functions to SetTime/Set for consistency
- improve: Standardize ERR_XXX_NEVER_DOWN error constants to ERR_XXX_NEVER_SET, with ERR_XXX_NEVER_DOWN kept as compatibility alias
- improve: More standard naming for interfaces and errors to improve maintainability and readability

uranus/uranus.go

@@ -10,7 +10,9 @@ import (
 
 var (
 	ERR_URANUS_NEVER_RISE = errors.New("ERROR:极夜，天王星今日永远在地平线下！")
-	ERR_URANUS_NEVER_DOWN = errors.New("ERROR:极昼，天王星今日永远在地平线上！")
+	ERR_URANUS_NEVER_SET  = errors.New("ERROR:极昼，天王星今日永远在地平线上！")
+	// ERR_URANUS_NEVER_DOWN deprecated -- use ERR_URANUS_NEVER_SET instead
+	ERR_URANUS_NEVER_DOWN = ERR_URANUS_NEVER_SET
 )
 
 // ApparentLo 视黄经
@@ -122,7 +124,7 @@ func RiseTime(date time.Time, lon, lat, height float64, aero bool) (time.Time, e
 		err = ERR_URANUS_NEVER_RISE
 	}
 	if riseJde == -1 {
-		err = ERR_URANUS_NEVER_DOWN
+		err = ERR_URANUS_NEVER_SET
 	}
 	return basic.JDE2DateByZone(riseJde, date.Location(), true), err
 }
@@ -150,7 +152,7 @@ func DownTime(date time.Time, lon, lat, height float64, aero bool) (time.Time, e
 		err = ERR_URANUS_NEVER_RISE
 	}
 	if riseJde == -1 {
-		err = ERR_URANUS_NEVER_DOWN
+		err = ERR_URANUS_NEVER_SET
 	}
 	return basic.JDE2DateByZone(riseJde, date.Location(), true), err
 }
@@ -205,7 +207,7 @@ func LastRetrogradeToPrograde(date time.Time) time.Time {
 }
 
 // NextRetrogradeToPrograde 上次留（逆转瞬）
-//// 返回上次逆转瞬留的时间
+// // 返回上次逆转瞬留的时间
 func NextRetrogradeToPrograde(date time.Time) time.Time {
 	jde := basic.TD2UT(basic.Date2JDE(date.UTC()), true)
 	return basic.JDE2DateByZone(basic.NextUranusRetrogradeToPrograde(jde), date.Location(), false)