Add repeater region discover

frontend/src/App.tsx

@@ -159,6 +159,9 @@ export function App() {
     meshDiscovery,
     meshDiscoveryLoadingTarget,
     handleDiscoverMesh,
+    regionDiscovery,
+    regionDiscoveryLoading,
+    handleDiscoverRegions,
     handleHealthRefresh,
   } = useRadioControl();
 
@@ -707,6 +710,9 @@ export function App() {
     meshDiscovery,
     meshDiscoveryLoadingTarget,
     onDiscoverMesh: handleDiscoverMesh,
+    regionDiscovery,
+    regionDiscoveryLoading,
+    onDiscoverRegions: handleDiscoverRegions,
     onHealthRefresh: handleHealthRefresh,
     onRefreshAppSettings: fetchAppSettings,
     blockedKeys: appSettings?.blocked_keys,

frontend/src/api.ts

@@ -19,6 +19,7 @@ import type {
   RadioConfig,
   RadioConfigUpdate,
   RadioDiscoveryResponse,
+  RadioRegionDiscoveryResponse,
   RadioTraceHopRequest,
   RadioTraceResponse,
   RadioDiscoveryTarget,
@@ -115,6 +116,11 @@ export const api = {
       method: 'POST',
       body: JSON.stringify({ target }),
     }),
+  discoverRegions: (publicKeys?: string[]) =>
+    fetchJson<RadioRegionDiscoveryResponse>('/radio/discover-regions', {
+      method: 'POST',
+      body: JSON.stringify(publicKeys && publicKeys.length > 0 ? { public_keys: publicKeys } : {}),
+    }),
   requestRadioTrace: (hopHashBytes: 1 | 2 | 4, hops: RadioTraceHopRequest[]) =>
     fetchJson<RadioTraceResponse>('/radio/trace', {
       method: 'POST',

frontend/src/components/SettingsModal.tsx

@@ -10,6 +10,7 @@ import type {
   RadioConfigUpdate,
   RadioDiscoveryResponse,
   RadioDiscoveryTarget,
+  RadioRegionDiscoveryResponse,
 } from '../types';
 import type { LocalLabel } from '../utils/localLabel';
 import {
@@ -43,6 +44,9 @@ interface SettingsModalBaseProps {
   meshDiscovery: RadioDiscoveryResponse | null;
   meshDiscoveryLoadingTarget: RadioDiscoveryTarget | null;
   onDiscoverMesh: (target: RadioDiscoveryTarget) => Promise<void>;
+  regionDiscovery: RadioRegionDiscoveryResponse | null;
+  regionDiscoveryLoading: boolean;
+  onDiscoverRegions: (publicKeys?: string[]) => Promise<void>;
   onHealthRefresh: () => Promise<void>;
   onRefreshAppSettings: () => Promise<void>;
   onLocalLabelChange?: (label: LocalLabel) => void;
@@ -83,6 +87,9 @@ export function SettingsModal(props: SettingsModalProps) {
     meshDiscovery,
     meshDiscoveryLoadingTarget,
     onDiscoverMesh,
+    regionDiscovery,
+    regionDiscoveryLoading,
+    onDiscoverRegions,
     onHealthRefresh,
     onRefreshAppSettings,
     onLocalLabelChange,
@@ -218,6 +225,9 @@ export function SettingsModal(props: SettingsModalProps) {
                 meshDiscovery={meshDiscovery}
                 meshDiscoveryLoadingTarget={meshDiscoveryLoadingTarget}
                 onDiscoverMesh={onDiscoverMesh}
+                regionDiscovery={regionDiscovery}
+                regionDiscoveryLoading={regionDiscoveryLoading}
+                onDiscoverRegions={onDiscoverRegions}
                 onClose={onClose}
                 className={sectionContentClass}
               />

frontend/src/components/settings/SettingsRadioSection.tsx

@@ -26,6 +26,7 @@ import type {
   RadioConfigUpdate,
   RadioDiscoveryResponse,
   RadioDiscoveryTarget,
+  RadioRegionDiscoveryResponse,
   RadioStatsSnapshot,
 } from '../../types';
 
@@ -151,6 +152,9 @@ export function SettingsRadioSection({
   meshDiscovery,
   meshDiscoveryLoadingTarget,
   onDiscoverMesh,
+  regionDiscovery,
+  regionDiscoveryLoading,
+  onDiscoverRegions,
   onClose,
   className,
 }: {
@@ -168,6 +172,9 @@ export function SettingsRadioSection({
   meshDiscovery: RadioDiscoveryResponse | null;
   meshDiscoveryLoadingTarget: RadioDiscoveryTarget | null;
   onDiscoverMesh: (target: RadioDiscoveryTarget) => Promise<void>;
+  regionDiscovery: RadioRegionDiscoveryResponse | null;
+  regionDiscoveryLoading: boolean;
+  onDiscoverRegions: (publicKeys?: string[]) => Promise<void>;
   onClose: () => void;
   className?: string;
 }) {
@@ -478,6 +485,34 @@ export function SettingsRadioSection({
     }
   };
 
+  const handleDiscoverRegions = async () => {
+    // Prefer repeaters from the most recent mesh-discovery sweep (they just
+    // answered, so they're likely in range for the direct-routed regions
+    // request); otherwise let the backend pick recent repeater contacts.
+    const discoveredRepeaterKeys = (meshDiscovery?.results ?? [])
+      .filter((r) => r.node_type === 'repeater')
+      .map((r) => r.public_key);
+    await onDiscoverRegions(discoveredRepeaterKeys);
+  };
+
+  const handleAddDiscoveredRegions = () => {
+    if (!regionDiscovery || regionDiscovery.regions.length === 0) return;
+    const existing = knownRegions
+      .split('\n')
+      .map((s) => s.trim())
+      .filter(Boolean);
+    const seen = new Set(existing.map((s) => s.toLowerCase()));
+    const additions = regionDiscovery.regions.filter((r) => !seen.has(r.toLowerCase()));
+    if (additions.length === 0) {
+      toast.info('All discovered regions are already listed');
+      return;
+    }
+    setKnownRegions([...existing, ...additions].join('\n'));
+    toast.success(
+      `Added ${additions.length} region${additions.length === 1 ? '' : 's'} — review and Save Messaging Settings`
+    );
+  };
+
   const importInputRef = useRef<HTMLInputElement>(null);
   const [keyImportDialogOpen, setKeyImportDialogOpen] = useState(false);
   const pendingImportRef = useRef<Record<string, unknown> | null>(null);
@@ -1186,6 +1221,72 @@ export function SettingsRadioSection({
           label instead of a raw transport code. Saving a change re-tags existing messages whose
           original packet is still stored.
         </p>
+
+        <div className="space-y-2 rounded-md border border-input bg-muted/20 p-3">
+          <div className="flex flex-wrap items-center justify-between gap-2">
+            <span className="text-[0.625rem] uppercase tracking-wider text-muted-foreground font-medium">
+              Discover regions from repeaters
+            </span>
+            <Button
+              type="button"
+              variant="outline"
+              size="sm"
+              onClick={handleDiscoverRegions}
+              disabled={regionDiscoveryLoading || !health?.radio_connected}
+            >
+              {regionDiscoveryLoading ? 'Asking repeaters...' : 'Discover Regions'}
+            </Button>
+          </div>
+          <p className="text-[0.8125rem] text-muted-foreground">
+            Asks nearby repeaters which regions they flood, so you can populate the list above. Uses
+            repeaters from your last mesh discovery sweep when available, otherwise your most
+            recently seen repeaters. Only repeaters in direct range answer, and this only reveals
+            flood-allowed regions (not blocked ones).
+          </p>
+          {!health?.radio_connected && (
+            <p className="text-sm text-destructive">Radio not connected</p>
+          )}
+          {regionDiscovery && (
+            <div className="space-y-2">
+              <p className="text-sm font-medium">
+                {regionDiscovery.repeaters_answered}/{regionDiscovery.repeaters_queried} repeater
+                {regionDiscovery.repeaters_queried === 1 ? '' : 's'} answered
+                {regionDiscovery.regions.length > 0
+                  ? ` — ${regionDiscovery.regions.length} region${regionDiscovery.regions.length === 1 ? '' : 's'} found`
+                  : ''}
+              </p>
+              {regionDiscovery.regions.length > 0 ? (
+                <>
+                  <div className="flex flex-wrap gap-1.5">
+                    {regionDiscovery.regions.map((region) => (
+                      <span
+                        key={region}
+                        className="text-[0.625rem] uppercase tracking-wider px-1.5 py-0.5 rounded bg-primary/10 font-mono"
+                      >
+                        {region}
+                      </span>
+                    ))}
+                  </div>
+                  <Button
+                    type="button"
+                    variant="outline"
+                    size="sm"
+                    onClick={handleAddDiscoveredRegions}
+                    className="border-success/50 text-success hover:bg-success/10"
+                  >
+                    Add to Known Regions
+                  </Button>
+                </>
+              ) : (
+                regionDiscovery.repeaters_queried > 0 && (
+                  <p className="text-sm text-muted-foreground">
+                    No flood-allowed regions were reported.
+                  </p>
+                )
+              )}
+            </div>
+          )}
+        </div>
       </div>
 
       <div className="space-y-2">

frontend/src/hooks/useRadioControl.ts

@@ -9,6 +9,7 @@ import type {
   RadioConfigUpdate,
   RadioDiscoveryResponse,
   RadioDiscoveryTarget,
+  RadioRegionDiscoveryResponse,
 } from '../types';
 
 export function useRadioControl() {
@@ -17,6 +18,8 @@ export function useRadioControl() {
   const [meshDiscovery, setMeshDiscovery] = useState<RadioDiscoveryResponse | null>(null);
   const [meshDiscoveryLoadingTarget, setMeshDiscoveryLoadingTarget] =
     useState<RadioDiscoveryTarget | null>(null);
+  const [regionDiscovery, setRegionDiscovery] = useState<RadioRegionDiscoveryResponse | null>(null);
+  const [regionDiscoveryLoading, setRegionDiscoveryLoading] = useState(false);
 
   const prevHealthRef = useRef<HealthStatus | null>(null);
   const rebootPollTokenRef = useRef(0);
@@ -127,6 +130,32 @@ export function useRadioControl() {
     }
   }, []);
 
+  const handleDiscoverRegions = useCallback(async (publicKeys?: string[]) => {
+    setRegionDiscoveryLoading(true);
+    try {
+      const data = await api.discoverRegions(publicKeys);
+      setRegionDiscovery(data);
+      if (data.repeaters_queried === 0) {
+        toast.info('No repeaters available to query for regions');
+      } else if (data.regions.length === 0) {
+        toast.info(
+          `No regions reported (${data.repeaters_answered}/${data.repeaters_queried} repeaters answered)`
+        );
+      } else {
+        toast.success(
+          `Found ${data.regions.length} region${data.regions.length === 1 ? '' : 's'} from ${data.repeaters_answered}/${data.repeaters_queried} repeaters`
+        );
+      }
+    } catch (err) {
+      console.error('Failed to discover regions:', err);
+      toast.error('Failed to discover regions', {
+        description: err instanceof Error ? err.message : 'Check radio connection',
+      });
+    } finally {
+      setRegionDiscoveryLoading(false);
+    }
+  }, []);
+
   const handleHealthRefresh = useCallback(async () => {
     try {
       const data = await api.getHealth();
@@ -152,6 +181,9 @@ export function useRadioControl() {
     meshDiscovery,
     meshDiscoveryLoadingTarget,
     handleDiscoverMesh,
+    regionDiscovery,
+    regionDiscoveryLoading,
+    handleDiscoverRegions,
     handleHealthRefresh,
   };
 }

frontend/src/test/settingsModal.test.tsx

@@ -12,6 +12,7 @@ import type {
   RadioConfigUpdate,
   RadioDiscoveryResponse,
   RadioDiscoveryTarget,
+  RadioRegionDiscoveryResponse,
   StatisticsResponse,
 } from '../types';
 import type { SettingsSection } from '../components/settings/settingsConstants';
@@ -93,6 +94,7 @@ function renderModal(overrides?: {
   meshDiscovery?: RadioDiscoveryResponse | null;
   meshDiscoveryLoadingTarget?: RadioDiscoveryTarget | null;
   onDiscoverMesh?: (target: RadioDiscoveryTarget) => Promise<void>;
+  regionDiscovery?: RadioRegionDiscoveryResponse | null;
   contacts?: Contact[];
   trackedTelemetryRepeaters?: string[];
   open?: boolean;
@@ -113,6 +115,7 @@ function renderModal(overrides?: {
   const onReconnect = overrides?.onReconnect ?? vi.fn(async () => {});
   const onAdvertise = overrides?.onAdvertise ?? vi.fn(async (_mode: RadioAdvertMode) => {});
   const onDiscoverMesh = overrides?.onDiscoverMesh ?? vi.fn(async () => {});
+  const onDiscoverRegions = vi.fn(async () => {});
 
   const commonProps = {
     open: overrides?.open ?? true,
@@ -131,6 +134,9 @@ function renderModal(overrides?: {
     meshDiscovery: overrides?.meshDiscovery ?? null,
     meshDiscoveryLoadingTarget: overrides?.meshDiscoveryLoadingTarget ?? null,
     onDiscoverMesh,
+    regionDiscovery: overrides?.regionDiscovery ?? null,
+    regionDiscoveryLoading: false,
+    onDiscoverRegions,
     onHealthRefresh: vi.fn(async () => {}),
     onRefreshAppSettings,
     contacts: overrides?.contacts,
@@ -158,6 +164,7 @@ function renderModal(overrides?: {
     onReconnect,
     onAdvertise,
     onDiscoverMesh,
+    onDiscoverRegions,
     view,
   };
 }
@@ -335,6 +342,67 @@ describe('SettingsModal', () => {
     expect(screen.getByText('8s listen window')).toBeInTheDocument();
   });
 
+  it('discovers regions using repeaters from the last mesh sweep', async () => {
+    const { onDiscoverRegions } = renderModal({
+      meshDiscovery: {
+        target: 'all',
+        duration_seconds: 8,
+        results: [
+          {
+            public_key: '11'.repeat(32),
+            name: 'RPT-A',
+            node_type: 'repeater',
+            heard_count: 1,
+            local_snr: 5,
+            local_rssi: -100,
+            remote_snr: 3,
+          },
+          {
+            public_key: '22'.repeat(32),
+            name: 'Sensor',
+            node_type: 'sensor',
+            heard_count: 1,
+            local_snr: 5,
+            local_rssi: -100,
+            remote_snr: 3,
+          },
+        ],
+      },
+    });
+    openRadioSection();
+
+    fireEvent.click(screen.getByRole('button', { name: 'Discover Regions' }));
+
+    // Only the repeater's key is passed, not the sensor's.
+    await waitFor(() => {
+      expect(onDiscoverRegions).toHaveBeenCalledWith(['11'.repeat(32)]);
+    });
+  });
+
+  it('adds discovered regions to the known-regions field', () => {
+    renderModal({
+      regionDiscovery: {
+        repeaters_queried: 2,
+        repeaters_answered: 2,
+        regions: ['nl-gr', 'de-by'],
+        results: [],
+      },
+    });
+    openRadioSection();
+
+    expect(screen.getByText('2/2 repeaters answered — 2 regions found')).toBeInTheDocument();
+
+    const knownRegions = screen.getByLabelText(
+      'Known Regions (for decoding)'
+    ) as HTMLTextAreaElement;
+    fireEvent.change(knownRegions, { target: { value: 'nl-gr' } });
+
+    fireEvent.click(screen.getByRole('button', { name: 'Add to Known Regions' }));
+
+    // Existing 'nl-gr' preserved, only the new 'de-by' appended.
+    expect(knownRegions.value).toBe('nl-gr\nde-by');
+  });
+
   it('saves advert location source through radio config save', async () => {
     const { onSave } = renderModal();
     openRadioSection();

frontend/src/types.ts

@@ -54,6 +54,21 @@ export interface RadioDiscoveryResponse {
   results: RadioDiscoveryResult[];
 }
 
+export interface RadioRegionDiscoveryRepeater {
+  public_key: string;
+  name: string | null;
+  answered: boolean;
+  regions: string[];
+}
+
+export interface RadioRegionDiscoveryResponse {
+  repeaters_queried: number;
+  repeaters_answered: number;
+  /** Deduplicated union of flood-allowed region names across all repeaters. */
+  regions: string[];
+  results: RadioRegionDiscoveryRepeater[];
+}
+
 export type RadioAdvertMode = 'flood' | 'zero_hop';
 
 export interface FanoutStatusEntry {