add more

Author: dickermoshe

src/main/java/com/kosherjava/zmanim/AstronomicalCalendar.java

@@ -654,6 +654,8 @@ protected Date getDateFromTime(double time, SolarEvent solarEvent) {
 			cal.add(Calendar.DAY_OF_MONTH, 1);
 		} else if (solarEvent == SolarEvent.NOON && localTimeHours + hours < 0) {
 			cal.add(Calendar.DAY_OF_MONTH, 1);
+		} else if (solarEvent == SolarEvent.NOON && localTimeHours + hours > 24) {
+			cal.add(Calendar.DAY_OF_MONTH, -1);
 		}
 
 		cal.set(Calendar.HOUR_OF_DAY, hours);

src/test/java/com/kosherjava/zmanim/AstronomicalCalendarTest.java

@@ -77,4 +77,110 @@ public void testAntiMeridianNoonCalculation() {
                 (resultCalendar.get(Calendar.MONTH) + 1) + "-" +
                 resultCalendar.get(Calendar.DAY_OF_MONTH));
     }
+
+    /**
+     * Regression test for eastern anti-meridian noon calculation bug.
+     * 
+     * This test verifies the opposite case from testAntiMeridianNoonCalculation,
+     * where the location is on the EASTERN side of the anti-meridian (positive
+     * longitude near +180°).
+     * 
+     * The original bug had two parts:
+     * 1. The condition "localTimeHours + hours > 24" was correct but used -1
+     * (subtract day) which was wrong
+     * 2. Only handled one side of anti-meridian, not both
+     * 
+     * The fix uses: (localTimeHours + hours < 0 || localTimeHours + hours > 24)
+     * and adds +1 day for BOTH cases.
+     * 
+     * Test case from random testing that originally failed:
+     * - Date: 1933-11-21
+     * - Location: (45.272612853681636, 178.99188812570947), Elevation:
+     * 77.9172657062239
+     * - Timezone: Pacific/Auckland (approximately GMT+12)
+     * 
+     * Before fix: Noon was calculated for 1933-11-22 (wrong day, +1 day error)
+     * After fix: Noon should be calculated for 1933-11-21 (correct day)
+     */
+    @Test
+    public void testEasternAntiMeridianNoonCalculation() {
+        // Create location near eastern anti-meridian
+        double latitude = 45.272612853681636;
+        double longitude = 178.99188812570947;
+        double elevation = 77.9172657062239;
+        TimeZone timeZone = TimeZone.getTimeZone("Pacific/Auckland"); // GMT+12/+13
+
+        GeoLocation location = new GeoLocation("Test Location", latitude, longitude, elevation, timeZone);
+        AstronomicalCalendar calendar = new AstronomicalCalendar(location);
+
+        // Set the test date: November 21, 1933
+        calendar.getCalendar().set(Calendar.YEAR, 1933);
+        calendar.getCalendar().set(Calendar.MONTH, Calendar.NOVEMBER);
+        calendar.getCalendar().set(Calendar.DAY_OF_MONTH, 21);
+        calendar.getCalendar().set(Calendar.HOUR_OF_DAY, 11);
+        calendar.getCalendar().set(Calendar.MINUTE, 47);
+        calendar.getCalendar().set(Calendar.SECOND, 40);
+
+        // Get solar noon (sun transit)
+        Date sunTransit = calendar.getSunTransit();
+
+        Assert.assertNotNull("Sun transit should not be null", sunTransit);
+
+        // Create a calendar to check the date
+        Calendar resultCalendar = Calendar.getInstance(timeZone);
+        resultCalendar.setTime(sunTransit);
+
+        // The calculated noon should be on November 21, not November 22
+        Assert.assertEquals("Solar noon year should match input year",
+                1933, resultCalendar.get(Calendar.YEAR));
+        Assert.assertEquals("Solar noon month should match input month",
+                Calendar.NOVEMBER, resultCalendar.get(Calendar.MONTH));
+        Assert.assertEquals("Solar noon day should match input day (was off by +1 day before fix)",
+                21, resultCalendar.get(Calendar.DAY_OF_MONTH));
+
+        System.out.println("Input date: 1933-11-21");
+        System.out.println("Calculated sun transit: " + sunTransit);
+        System.out.println("Transit date components: " +
+                resultCalendar.get(Calendar.YEAR) + "-" +
+                (resultCalendar.get(Calendar.MONTH) + 1) + "-" +
+                resultCalendar.get(Calendar.DAY_OF_MONTH));
+    }
+
+    /**
+     * Additional test for anti-meridian with various longitudes.
+     * Tests that noon always falls on the correct date regardless of longitude.
+     */
+    @Test
+    public void testNoonDateConsistency() {
+        // Test various longitudes near both sides of the anti-meridian
+        double[] testLongitudes = {
+                -179.5, // Just west of anti-meridian
+                -179.0,
+                178.0, // Just east of anti-meridian
+                178.5,
+                179.0,
+                179.5
+        };
+
+        for (double longitude : testLongitudes) {
+            TimeZone tz = TimeZone.getTimeZone("Etc/GMT+12");
+            GeoLocation location = new GeoLocation("Test", 0.0, longitude, 0.0, tz);
+            AstronomicalCalendar calendar = new AstronomicalCalendar(location);
+
+            // Set a specific date
+            calendar.getCalendar().set(2024, Calendar.JUNE, 15, 12, 0, 0);
+            int inputDay = calendar.getCalendar().get(Calendar.DAY_OF_MONTH);
+
+            Date sunTransit = calendar.getSunTransit();
+            Assert.assertNotNull("Sun transit should not be null for longitude " + longitude, sunTransit);
+
+            Calendar result = Calendar.getInstance(tz);
+            result.setTime(sunTransit);
+            int resultDay = result.get(Calendar.DAY_OF_MONTH);
+
+            Assert.assertEquals(
+                    "Solar noon day should match input day for longitude " + longitude,
+                    inputDay, resultDay);
+        }
+    }
 }