From 3885fd52fefc3167524aacd6268ed518cd3269df Mon Sep 17 00:00:00 2001
From: Viktor Barzin <viktorbarzin@meta.com>
Date: Sun, 22 Feb 2026 13:29:35 +0000
Subject: [PATCH] Add bulk POI distances endpoint for decoupled loading

New GET /api/poi/distances/bulk returns all POI distances keyed by
listing ID, allowing the frontend to fetch distances separately
from the listing stream and keep the stream on the cached path.
---
 api/poi_routes.py                   | 36 +++++++++++++++++++++++++++++
 frontend/src/services/index.ts      |  2 +-
 frontend/src/services/poiService.ts |  9 ++++++++
 3 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/api/poi_routes.py b/api/poi_routes.py
index eb74841..8d2c256 100644
--- a/api/poi_routes.py
+++ b/api/poi_routes.py
@@ -172,6 +172,42 @@ async def calculate_distances(
     return {"task_id": result.task_id or "", "message": result.message}
 
 
+@poi_router.get("/distances/bulk")
+async def get_bulk_distances(
+    user: Annotated[User, Depends(get_current_user)],
+    listing_type: ListingType = ListingType.RENT,
+) -> dict[int, list[POIDistanceResponse]]:
+    """Get all POI distances for the current user, keyed by listing ID."""
+    user_id = _get_user_id(user)
+    repo = POIRepository(engine)
+    pois = {p.id: p for p in poi_service.get_user_pois(repo, user_id)}
+    if not pois:
+        return {}
+
+    from repositories.listing_repository import ListingRepository
+    from database import engine as db_engine
+    listing_repo = ListingRepository(db_engine)
+    all_ids = list(listing_repo.get_listing_ids(listing_type))
+    if not all_ids:
+        return {}
+
+    distances = repo.get_distances_for_listings(all_ids, listing_type, user_id)
+
+    result: dict[int, list[POIDistanceResponse]] = {}
+    for d in distances:
+        poi_name = pois[d.poi_id].name if d.poi_id in pois else "Unknown"
+        result.setdefault(d.listing_id, []).append(
+            POIDistanceResponse(
+                poi_id=d.poi_id,
+                poi_name=poi_name,
+                travel_mode=d.travel_mode,
+                duration_seconds=d.duration_seconds,
+                distance_meters=d.distance_meters,
+            )
+        )
+    return result
+
+
 @poi_router.get("/distances")
 async def get_distances(
     user: Annotated[User, Depends(get_current_user)],
diff --git a/frontend/src/services/index.ts b/frontend/src/services/index.ts
index a081b7d..e3b11e0 100644
--- a/frontend/src/services/index.ts
+++ b/frontend/src/services/index.ts
@@ -4,6 +4,6 @@ export { fetchListingGeoJSON, refreshListings } from './listingService';
 export { streamListingGeoJSON, type StreamingProgress } from './streamingService';
 export { fetchTasksForUser, fetchTaskStatus, cancelTask, clearAllTasks, type CancelTaskResponse, type ClearAllTasksResponse } from './taskService';
 export { checkBackendHealth, type HealthStatus, type HealthCheckResult } from './healthService';
-export { fetchUserPOIs, createPOI, updatePOI, deletePOI, triggerPOICalculation, fetchPOIDistances } from './poiService';
+export { fetchUserPOIs, createPOI, updatePOI, deletePOI, triggerPOICalculation, fetchPOIDistances, fetchBulkPOIDistances } from './poiService';
 export { fetchDecisions, setDecision, clearDecision } from './decisionService';
 export { fetchListingDetail } from './listingDetailService';
diff --git a/frontend/src/services/poiService.ts b/frontend/src/services/poiService.ts
index 7529735..187f244 100644
--- a/frontend/src/services/poiService.ts
+++ b/frontend/src/services/poiService.ts
@@ -62,3 +62,12 @@ export async function fetchPOIDistances(
     },
   });
 }
+
+export async function fetchBulkPOIDistances(
+  user: AuthUser,
+  listingType: 'RENT' | 'BUY' = 'RENT'
+): Promise<Record<number, POIDistanceInfo[]>> {
+  return apiRequest<Record<number, POIDistanceInfo[]>>(user, '/api/poi/distances/bulk', {
+    params: { listing_type: listingType },
+  });
+}