feat(search): compose Google and Photon through an explicit provider service

src/search/google.js

@@ -0,0 +1,66 @@
+/** Normalize a Google forward-geocode result without leaking its address shape. */
+export function normalizeGooglePlace(result) {
+  const lat = result?.geometry?.location?.lat;
+  const lng = result?.geometry?.location?.lng;
+  if (
+    !Number.isFinite(lat) ||
+    !Number.isFinite(lng) ||
+    Math.abs(lat) > 90 ||
+    Math.abs(lng) > 180
+  )
+    return null;
+  const types = Array.isArray(result.types) ? result.types : [];
+  const resultTypes = new Set(types.map((type) => String(type).toLowerCase()));
+  const components = Array.isArray(result.address_components)
+    ? result.address_components
+    : [];
+  // Address-only landmark results must retain the requested landmark identity.
+  const canonical = components.find(
+    (component) =>
+      Array.isArray(component.types) &&
+      component.types.some(
+        (type) =>
+          type !== 'political' && resultTypes.has(String(type).toLowerCase()),
+      ),
+  );
+  return {
+    lat,
+    lng,
+    name: canonical?.long_name || '',
+    label: result.formatted_address || '',
+    types,
+    viewport: result.geometry.bounds || result.geometry.viewport || null,
+  };
+}
+
+/** Construct Google geocoding with caller-owned transport and key selection. */
+export function createGoogleGeocoder({ request }) {
+  return {
+    async geocode(query, { bias = null, signal } = {}) {
+      signal?.throwIfAborted();
+      try {
+        const response = await request(query, { bias, signal });
+        signal?.throwIfAborted();
+        // An unconfigured provider did not contribute a negative verdict.
+        if (!response) return { place: null, answered: true };
+        if (response.ok === false) return { place: null, answered: false };
+        const data = await response.json();
+        signal?.throwIfAborted();
+        if (
+          data?.status === 'ZERO_RESULTS' &&
+          Array.isArray(data.results) &&
+          data.results.length === 0
+        )
+          return { place: null, answered: true };
+        const place =
+          data?.status === 'OK'
+            ? normalizeGooglePlace(data.results?.[0])
+            : null;
+        return { place, answered: Boolean(place) };
+      } catch {
+        signal?.throwIfAborted();
+        return { place: null, answered: false };
+      }
+    },
+  };
+}