Fix nearby stop grouping and location fallback

worker/nta-proxy.js

@@ -42,9 +42,9 @@ async function fetchStops(env) {
 }
 
 async function fetchDepartures(url, env, ctx) {
-  const stopId = url.searchParams.get('stopId') ?? ''
-  const stopCode = url.searchParams.get('stopCode') ?? ''
-  if (!stopId && !stopCode) {
+  const stopIds = uniqueQueryValues(url.searchParams, 'stopId')
+  const stopCodes = uniqueQueryValues(url.searchParams, 'stopCode')
+  if (!stopIds.length && !stopCodes.length) {
     return json({ departures: [], error: 'stopId or stopCode is required' }, 400)
   }
   if (!env.NTA_API_KEY) {
@@ -53,7 +53,7 @@ async function fetchDepartures(url, env, ctx) {
 
   const feed = await getTripUpdateFeed(env, ctx)
   return json({
-    departures: parseTripUpdates(feed, stopId, stopCode),
+    departures: parseTripUpdates(feed, stopIds, stopCodes),
     updatedAt: Date.now(),
   })
 }
@@ -86,9 +86,10 @@ async function getTripUpdateFeed(env, ctx) {
   return payload
 }
 
-function parseTripUpdates(payload, stopId, stopCode) {
+function parseTripUpdates(payload, stopIds, stopCodes) {
   const entities = Array.isArray(payload?.entity) ? payload.entity : []
   const departures = []
+  const stopIdSet = new Set([...stopIds, ...stopCodes])
 
   for (const entity of entities) {
     const tripUpdate = entity.tripUpdate || entity.trip_update || {}
@@ -99,7 +100,7 @@ function parseTripUpdates(payload, stopId, stopCode) {
 
     for (const update of updates) {
       const updateStopId = update.stopId || update.stop_id
-      if (updateStopId !== stopId && updateStopId !== stopCode) {
+      if (!stopIdSet.has(updateStopId)) {
         continue
       }
 
@@ -131,6 +132,10 @@ function parseTripUpdates(payload, stopId, stopCode) {
   return departures.sort((a, b) => a.dueMinutes - b.dueMinutes).slice(0, 40)
 }
 
+function uniqueQueryValues(params, key) {
+  return [...new Set(params.getAll(key).flatMap((value) => value.split(',')).map((value) => value.trim()).filter(Boolean))]
+}
+
 function json(body, status = 200, headers = {}) {
   return new Response(JSON.stringify(body), {
     status,