refactor: extract shared utility functions to eliminate duplication

frontend/src/App.tsx

@@ -22,6 +22,7 @@ import { getCached, setCached, invalidateAll as invalidateListingCache } from '@
 import { setOnUnauthorized } from '@/services/apiClient';
 import { clearPasskeyUser } from './auth/passkeyService';
 import { poiMetricPropertyName, injectPoiMetricProperty } from '@/utils/poiUtils';
+import { isTerminalStatus } from '@/utils/taskUtils';
 import { useTaskProgress } from '@/hooks/useTaskProgress';
 import { useDecisions } from '@/hooks/useDecisions';
 import { useIsMobile } from '@/hooks/use-mobile';
@@ -30,10 +31,6 @@ import { SwipeReviewMode } from './components/SwipeReviewMode';
 import { FavoritesView } from './components/FavoritesView';
 import { ListingDetailSheet } from './components/ListingDetailSheet';
 
-function isTerminalStatus(status: string): boolean {
-  return status === 'SUCCESS' || status === 'FAILURE' || status === 'REVOKED';
-}
-
 function App() {
   const [listingData, setListingData] = useState<GeoJSONFeatureCollection | null>(null);
   const [user, setUser] = useState<AuthUser | null>(null);

frontend/src/components/ListingDetail.tsx

@@ -2,12 +2,7 @@ import { ExternalLink, Heart, X, Bed, Maximize2, PoundSterling, Building, Clock,
 import { Button } from './ui/button';
 import { PhotoCarousel } from './PhotoCarousel';
 import type { ListingDetailData, DecisionType, POIDistanceInfo } from '@/types';
-
-function formatDate(value: string): string {
-    const date = new Date(value);
-    if (isNaN(date.getTime())) return value;
-    return date.toLocaleDateString('en-GB', { day: 'numeric', month: 'short', year: 'numeric' });
-}
+import { formatDate, formatDuration } from '@/utils/format';
 
 interface ListingDetailProps {
   detail: ListingDetailData;
@@ -15,14 +10,6 @@ interface ListingDetailProps {
   onClearDecision: () => void;
 }
 
-function formatDuration(seconds: number): string {
-  const minutes = Math.round(seconds / 60);
-  if (minutes < 60) return `${minutes}m`;
-  const hours = Math.floor(minutes / 60);
-  const mins = minutes % 60;
-  return mins > 0 ? `${hours}h${mins}m` : `${hours}h`;
-}
-
 function TravelModeIcon({ mode }: { mode: string }) {
   switch (mode) {
     case 'WALK': return <Footprints className="h-3 w-3" />;

frontend/src/components/MobileBottomSheet.tsx

@@ -4,6 +4,7 @@ import { MapPin, PoundSterling } from 'lucide-react';
 import { SwipeableCardRow } from './SwipeableCardRow';
 import { ListView } from './ListView';
 import type { GeoJSONFeatureCollection, PropertyProperties, PropertyFeature } from '@/types';
+import { formatCurrency } from '@/utils/format';
 
 interface MobileBottomSheetProps {
     listingData: GeoJSONFeatureCollection | null;
@@ -14,11 +15,6 @@ interface MobileBottomSheetProps {
     onSnapChange?: (snap: string | number | null) => void;
 }
 
-function formatCurrency(value: number): string {
-    if (value >= 1000) return `£${(value / 1000).toFixed(1)}k`;
-    return `£${Math.round(value)}`;
-}
-
 export function MobileBottomSheet({
     listingData,
     onPropertyClick,

frontend/src/components/PropertyCard.tsx

@@ -3,20 +3,7 @@ import useEmblaCarousel from 'embla-carousel-react';
 import { ExternalLink, Bed, Maximize2, PoundSterling, Clock, Building, Footprints, Bike, Train } from 'lucide-react';
 import { Button } from './ui/button';
 import type { PropertyProperties, POIDistanceInfo, POI } from '@/types';
-
-function formatDate(value: string): string {
-    const date = new Date(value);
-    if (isNaN(date.getTime())) return value;
-    return date.toLocaleDateString('en-GB', { day: 'numeric', month: 'short', year: 'numeric' });
-}
-
-function formatDuration(seconds: number): string {
-    const minutes = Math.round(seconds / 60);
-    if (minutes < 60) return `${minutes}m`;
-    const hours = Math.floor(minutes / 60);
-    const mins = minutes % 60;
-    return mins > 0 ? `${hours}h${mins}m` : `${hours}h`;
-}
+import { formatDate, formatDuration } from '@/utils/format';
 
 function TravelModeIcon({ mode }: { mode: string }) {
     switch (mode) {

frontend/src/components/StatsBar.tsx

@@ -1,6 +1,7 @@
 import { BarChart3, MapPin, PoundSterling, Maximize2, List, Map as MapIcon, Heart } from 'lucide-react';
 import { Button } from './ui/button';
 import type { GeoJSONFeatureCollection, PropertyFeature } from '@/types';
+import { formatCurrency } from '@/utils/format';
 
 export type ViewMode = 'map' | 'list' | 'split' | 'saved';
 
@@ -53,13 +54,6 @@ function calculateStats(data: GeoJSONFeatureCollection | null): ListingStats {
     return { count, avgPrice, avgPricePerSqm, avgSize };
 }
 
-function formatCurrency(value: number): string {
-    if (value >= 1000) {
-        return `£${(value / 1000).toFixed(1)}k`;
-    }
-    return `£${Math.round(value)}`;
-}
-
 export function StatsBar({ listingData, viewMode, onViewModeChange, likedCount = 0 }: StatsBarProps) {
     const stats = calculateStats(listingData);
 

frontend/src/components/TaskIndicator.tsx

@@ -4,6 +4,7 @@ import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from './ui/t
 import { Button } from './ui/button';
 import { Loader2, CheckCircle2, XCircle, X, Trash2 } from 'lucide-react';
 import { TaskProgressDrawer } from './TaskProgressDrawer';
+import { isTerminalStatus, taskStateToResult } from '@/utils/taskUtils';
 
 interface TaskIndicatorProps {
     tasks: Record<string, TaskState>;
@@ -14,37 +15,6 @@ interface TaskIndicatorProps {
     onTaskCompleted?: () => void;
 }
 
-/** Convert a TaskState into a TaskResult (for the drawer). */
-function taskStateToResult(ts: TaskState): TaskResult {
-    return {
-        progress: ts.progress ?? 0,
-        processed: ts.processed,
-        total: ts.total,
-        phase: ts.phase,
-        message: ts.message,
-        subqueries_probed: ts.subqueries_probed,
-        subqueries_initial: ts.subqueries_initial,
-        estimated_results: ts.estimated_results,
-        subqueries_total: ts.subqueries_total,
-        subqueries_completed: ts.subqueries_completed,
-        ids_collected: ts.ids_collected,
-        pages_fetched: ts.pages_fetched,
-        fetching_done: ts.fetching_done,
-        details_fetched: ts.details_fetched,
-        images_downloaded: ts.images_downloaded,
-        ocr_completed: ts.ocr_completed,
-        failed: ts.failed,
-        elapsed_seconds: ts.elapsed_seconds,
-        rate_per_second: ts.rate_per_second,
-        eta_seconds: ts.eta_seconds,
-        logs: ts.logs,
-    };
-}
-
-function isTerminalStatus(status: string): boolean {
-    return status === 'SUCCESS' || status === 'FAILURE' || status === 'REVOKED';
-}
-
 export function TaskIndicator({
     tasks,
     activeTaskId,

frontend/src/components/TaskProgressDrawer.tsx

@@ -11,6 +11,7 @@ import { Button } from './ui/button';
 import { CheckCircle2, Circle, Loader2, XCircle, MapPin, Search } from 'lucide-react';
 import { useEffect, useRef, useMemo } from 'react';
 import { useIsMobile } from '@/hooks/use-mobile';
+import { isTerminalStatus, taskStateToResult } from '@/utils/taskUtils';
 
 interface TaskProgressDrawerProps {
     open: boolean;
@@ -62,10 +63,6 @@ function taskTypeIcon(type: 'scrape' | 'poi' | 'task') {
     }
 }
 
-function isTerminalStatus(status: string): boolean {
-    return status === 'SUCCESS' || status === 'FAILURE' || status === 'REVOKED';
-}
-
 function getPhaseIndex(phase: TaskPhase | undefined): number {
     if (!phase) return -1;
     if (phase === 'splitting_complete') return 1;
@@ -324,33 +321,6 @@ function LogViewer({ logs }: { logs: string[] }) {
     );
 }
 
-/** Convert TaskState → TaskResult for existing phase detail components. */
-function taskStateToResult(ts: TaskState): TaskResult {
-    return {
-        progress: ts.progress ?? 0,
-        processed: ts.processed,
-        total: ts.total,
-        phase: ts.phase,
-        message: ts.message,
-        subqueries_probed: ts.subqueries_probed,
-        subqueries_initial: ts.subqueries_initial,
-        estimated_results: ts.estimated_results,
-        subqueries_total: ts.subqueries_total,
-        subqueries_completed: ts.subqueries_completed,
-        ids_collected: ts.ids_collected,
-        pages_fetched: ts.pages_fetched,
-        fetching_done: ts.fetching_done,
-        details_fetched: ts.details_fetched,
-        images_downloaded: ts.images_downloaded,
-        ocr_completed: ts.ocr_completed,
-        failed: ts.failed,
-        elapsed_seconds: ts.elapsed_seconds,
-        rate_per_second: ts.rate_per_second,
-        eta_seconds: ts.eta_seconds,
-        logs: ts.logs,
-    };
-}
-
 function TaskTabBar({
     tasks,
     selectedTaskId,

frontend/src/hooks/useTaskProgress.ts

@@ -3,6 +3,7 @@ import type { AuthUser } from '@/auth/types';
 import type { TaskState, TaskStatusResponse, WSMessage } from '@/types';
 import { WS_TASKS_PATH } from '@/constants';
 import { fetchTasksForUser, fetchTaskStatus } from '@/services';
+import { isTerminalStatus } from '@/utils/taskUtils';
 
 const KEEPALIVE_MS = 30_000;
 const MAX_RECONNECT_DELAY_MS = 30_000;
@@ -14,10 +15,6 @@ function wsUrl(token: string): string {
   return `${proto}://${window.location.host}${WS_TASKS_PATH}?token=${encodeURIComponent(token)}`;
 }
 
-function isTerminalStatus(status: string): boolean {
-  return status === 'SUCCESS' || status === 'FAILURE' || status === 'REVOKED';
-}
-
 /** Convert an HTTP TaskStatusResponse into the canonical TaskState shape. */
 function httpResponseToTaskState(resp: TaskStatusResponse): TaskState {
   const state: TaskState = {

frontend/src/utils/format.ts

@@ -0,0 +1,37 @@
+/**
+ * Shared formatting utility functions.
+ *
+ * Consolidates duplicated formatters that were previously defined inline in
+ * PropertyCard, ListingDetail, MobileBottomSheet, and StatsBar.
+ */
+
+/** Format a number as a compact GBP string, e.g. "£1.2k" or "£950". */
+export function formatCurrency(value: number): string {
+    if (value >= 1000) return `£${(value / 1000).toFixed(1)}k`;
+    return `£${Math.round(value)}`;
+}
+
+/** Format a duration in seconds as a human-readable string, e.g. "12m" or "1h30m". */
+export function formatDuration(seconds: number): string {
+    const minutes = Math.round(seconds / 60);
+    if (minutes < 60) return `${minutes}m`;
+    const hours = Math.floor(minutes / 60);
+    const mins = minutes % 60;
+    return mins > 0 ? `${hours}h${mins}m` : `${hours}h`;
+}
+
+/** Format an ISO date string as a localised short date (e.g. "3 Jan 2025"). */
+export function formatDate(value: string): string {
+    const date = new Date(value);
+    if (isNaN(date.getTime())) return value;
+    return date.toLocaleDateString('en-GB', { day: 'numeric', month: 'short', year: 'numeric' });
+}
+
+/**
+ * Compute the price per square metre as a formatted string, e.g. "£4,500/m²".
+ * Returns null when square metres data is unavailable.
+ */
+export function formatPricePerSqm(price: number, sqm: number | null | undefined): string | null {
+    if (sqm == null || sqm <= 0) return null;
+    return `£${Math.round(price / sqm).toLocaleString()}/m²`;
+}

frontend/src/utils/taskUtils.ts

@@ -0,0 +1,40 @@
+/**
+ * Shared task-related utility functions.
+ *
+ * Consolidates helpers that were duplicated across App.tsx, TaskIndicator.tsx,
+ * TaskProgressDrawer.tsx, and useTaskProgress.ts.
+ */
+
+import type { TaskState, TaskResult } from '@/types';
+
+/** Returns true when the status represents a terminal (finished) task state. */
+export function isTerminalStatus(status: string): boolean {
+    return status === 'SUCCESS' || status === 'FAILURE' || status === 'REVOKED';
+}
+
+/** Convert a TaskState into a TaskResult (for the drawer). */
+export function taskStateToResult(ts: TaskState): TaskResult {
+    return {
+        progress: ts.progress ?? 0,
+        processed: ts.processed,
+        total: ts.total,
+        phase: ts.phase,
+        message: ts.message,
+        subqueries_probed: ts.subqueries_probed,
+        subqueries_initial: ts.subqueries_initial,
+        estimated_results: ts.estimated_results,
+        subqueries_total: ts.subqueries_total,
+        subqueries_completed: ts.subqueries_completed,
+        ids_collected: ts.ids_collected,
+        pages_fetched: ts.pages_fetched,
+        fetching_done: ts.fetching_done,
+        details_fetched: ts.details_fetched,
+        images_downloaded: ts.images_downloaded,
+        ocr_completed: ts.ocr_completed,
+        failed: ts.failed,
+        elapsed_seconds: ts.elapsed_seconds,
+        rate_per_second: ts.rate_per_second,
+        eta_seconds: ts.eta_seconds,
+        logs: ts.logs,
+    };
+}