Add error handling for moon position calculation

index.html

@@ -364,58 +364,60 @@
         }
 
         function getMoonPosition(now, moonTimes) {
-            var rise = moonTimes.rise;
+            try {
-            var set = moonTimes.set;
+                var rise = moonTimes.rise;
+                var set = moonTimes.set;
 
-            if (!rise || !set) {
+                if (!rise || !set) {
-                return { point: pointOnCircle(now, MOON_ORBIT_RADIUS), isVisible: false };
+                    return { point: pointOnCircle(now, MOON_ORBIT_RADIUS), isVisible: false };
-            }
-
-            // Determine if moon is visible (above horizon)
-            var isVisible;
-            if (rise <= set) {
-                isVisible = (now >= rise && now <= set);
-            } else {
-                isVisible = (now >= rise || now <= set);
-            }
-
-            if (!isVisible) {
-                // Below horizon - position based on current time (grayed out)
-                return { point: pointOnCircle(now, MOON_ORBIT_RADIUS), isVisible: false };
-            }
-
-            // Above horizon - interpolate between moonrise and moonset
-            var riseAngle = angleForTime(rise);
-            var setAngle = angleForTime(set);
-
-            // Calculate the angular difference (could be negative if crossing midnight)
-            var diff = setAngle - riseAngle;
-            // Normalize so we take the "shorter" path that matches the moon arc
-            if (diff > Math.PI) diff -= 2 * Math.PI;
-            if (diff < -Math.PI) diff += 2 * Math.PI;
-
-            // Calculate progress (0 at rise, 1 at set)
-            var progress;
-            if (rise <= set) {
-                progress = (now.getTime() - rise.getTime()) / (set.getTime() - rise.getTime());
-            } else {
-                if (now >= rise) {
-                    var endMs = set.getTime() + 24 * 3600 * 1000;
-                    progress = (now.getTime() - rise.getTime()) / (endMs - rise.getTime());
-                } else {
-                    progress = (now.getTime() + 24 * 3600 * 1000 - rise.getTime()) /
-                               (set.getTime() + 24 * 3600 * 1000 - rise.getTime());
                 }
-            }
 
-            var moonAngle = riseAngle + diff * progress;
+                // Determine if moon is visible (above horizon)
-            return {
+                var isVisible;
-                point: {
+                if (rise <= set) {
-                    x: 100 + Math.cos(moonAngle) * MOON_ORBIT_RADIUS,
+                    isVisible = (now >= rise && now <= set);
-                    y: 100 + Math.sin(moonAngle) * MOON_ORBIT_RADIUS
+                } else {
-                },
+                    isVisible = (now >= rise || now <= set);
-                isVisible: true
+                }
-            };
+
+                if (!isVisible) {
+                    return { point: pointOnCircle(now, MOON_ORBIT_RADIUS), isVisible: false };
+                }
+
+                // Above horizon - interpolate between moonrise and moonset
+                var riseAngle = angleForTime(rise);
+                var setAngle = angleForTime(set);
+
+                // Calculate the angular difference (could be negative if crossing midnight)
+                var diff = setAngle - riseAngle;
+                if (diff > Math.PI) diff -= 2 * Math.PI;
+                if (diff < -Math.PI) diff += 2 * Math.PI;
+
+                // Calculate progress (0 at rise, 1 at set)
+                var progress;
+                if (rise <= set) {
+                    progress = (now.getTime() - rise.getTime()) / (set.getTime() - rise.getTime());
+                } else {
+                    if (now >= rise) {
+                        var endMs = set.getTime() + 24 * 3600 * 1000;
+                        progress = (now.getTime() - rise.getTime()) / (endMs - rise.getTime());
+                    } else {
+                        progress = (now.getTime() + 24 * 3600 * 1000 - rise.getTime()) /
+                                   (set.getTime() + 24 * 3600 * 1000 - rise.getTime());
+                    }
+                }
+
+                var moonAngle = riseAngle + diff * progress;
+                return {
+                    point: {
+                        x: 100 + Math.cos(moonAngle) * MOON_ORBIT_RADIUS,
+                        y: 100 + Math.sin(moonAngle) * MOON_ORBIT_RADIUS
+                    },
+                    isVisible: true
+                };
+            } catch (e) {
+                return { point: pointOnCircle(now, MOON_ORBIT_RADIUS), isVisible: false };
+            }
         }
 
         function renderMoonPhaseIcon(phase) {
@@ -538,8 +540,15 @@
 
             // Moon position - interpolated between moonrise and moonset on the orbit
             var moonPos = getMoonPosition(now, moonTimes);
-            rpgMoon.setAttribute('transform', 'translate(' + moonPos.point.x + ', ' + moonPos.point.y + ')');
+            if (!moonPos || !moonPos.point || isNaN(moonPos.point.x) || isNaN(moonPos.point.y)) {
-            rpgMoon.setAttribute('opacity', moonPos.isVisible ? '1' : '0.35');
+                // Fallback to current time position
+                var fallbackP = pointOnCircle(now, MOON_ORBIT_RADIUS);
+                rpgMoon.setAttribute('transform', 'translate(' + fallbackP.x + ', ' + fallbackP.y + ')');
+                rpgMoon.setAttribute('opacity', '0.35');
+            } else {
+                rpgMoon.setAttribute('transform', 'translate(' + moonPos.point.x + ', ' + moonPos.point.y + ')');
+                rpgMoon.setAttribute('opacity', moonPos.isVisible ? '1' : '0.35');
+            }
 
             // Sun rise/set arrows
             var srP = pointOnCircle(sunTimes.sunrise, SUN_ORBIT_RADIUS);