Iirolta saatu

src/utils.ts

@@ -0,0 +1,33 @@
+export function haversineDistance(lat1: number, lon1: number, lat2: number, lon2: number): number {
+  const R = 6371e3; // Earth radius in meters
+  const φ1 = (lat1 * Math.PI) / 180;
+  const φ2 = (lat2 * Math.PI) / 180;
+  const Δφ = ((lat2 - lat1) * Math.PI) / 180;
+  const Δλ = ((lon2 - lon1) * Math.PI) / 180;
+
+  const a =
+    Math.sin(Δφ / 2) * Math.sin(Δφ / 2) +
+    Math.cos(φ1) * Math.cos(φ2) * Math.sin(Δλ / 2) * Math.sin(Δλ / 2);
+  const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
+
+  return R * c; // Distance in meters
+}
+
+export async function reverseGeocode(lat: number, lon: number): Promise<string | undefined> {
+  try {
+    const response = await fetch(
+      `https://nominatim.openstreetmap.org/reverse?format=json&lat=${lat}&lon=${lon}&zoom=14&addressdetails=1`,
+      {
+        headers: {
+          'Accept-Language': 'en,fi'
+        }
+      }
+    );
+    if (!response.ok) return undefined;
+    const data = await response.json();
+    return data.display_name || data.name || undefined;
+  } catch (error) {
+    console.error('Geocoding failed:', error);
+    return undefined;
+  }
+}