Java-parity for arrivals/departures: deviation + distance + tripStatus

internal/restapi/arrival_and_departure_for_stop_handler.go

@@ -1,7 +1,6 @@
 package restapi
 
 import (
-	"context"
 	"database/sql"
 	"errors"
 	"net/http"
@@ -37,7 +36,7 @@ func parseArrivalAndDepartureParams(r *http.Request, loc ...*time.Location) (Arr
 	fieldErrors := make(map[string][]string)
 
 	const maxMinutesAfter = 240
-	const maxMinutesBefore = 60
+	const maxMinutesBefore = 240
 
 	// Validate minutesAfter
 	if minutesAfterStr := r.URL.Query().Get("minutesAfter"); minutesAfterStr != "" {
@@ -185,7 +184,11 @@ func (api *RestAPI) arrivalAndDepartureForStopHandler(w http.ResponseWriter, r *
 
 	stopAgency, err := api.GtfsManager.GtfsDB.Queries.GetAgency(ctx, stopAgencyID)
 	if err != nil {
-		api.serverErrorResponse(w, r, err)
+		if errors.Is(err, sql.ErrNoRows) {
+			api.sendNotFound(w, r)
+		} else {
+			api.serverErrorResponse(w, r, err)
+		}
 		return
 	}
 
@@ -351,14 +354,20 @@ func (api *RestAPI) arrivalAndDepartureForStopHandler(w http.ResponseWriter, r *
 			predicted = false
 		}
 
-		if vehicle != nil && vehicle.Position != nil {
-			distanceFromStop = api.getBlockDistanceToStop(ctx, tripID, stopCode, vehicle, serviceDate)
-
-			numberOfStopsAwayPtr := api.getNumberOfStopsAway(ctx, tripID, int(targetStopTime.StopSequence), vehicle, serviceDate)
-			if numberOfStopsAwayPtr != nil {
-				numberOfStopsAway = *numberOfStopsAwayPtr
-			} else {
-				numberOfStopsAway = -1
+		// Interpolate the block schedule at currentTime−scheduleDeviation.
+		// GPS lat/lon doesn't enter the formula. No RT vehicle → no shift.
+		effectiveTime := currentTime
+		if vehicle != nil && vehicle.Trip != nil && vehicle.Trip.ID.ID != "" {
+			blockTripIDs := api.blockTripIDsSortedByStartTime(ctx,
+				api.blockTripIDsForServiceDate(ctx, tripID, serviceDate))
+			if dev, hasRT := api.GetScheduleDeviationForBlock(ctx, blockTripIDs, serviceDate, currentTime); hasRT {
+				effectiveTime = currentTime.Add(-time.Duration(dev) * time.Second)
+			}
+		}
+		if snapshot := api.computeScheduledBlockSnapshot(ctx, tripID, effectiveTime, serviceDate); snapshot != nil {
+			if d, n, ok := snapshot.metricsForStop(tripID, int(targetStopTime.StopSequence)); ok {
+				distanceFromStop = d
+				numberOfStopsAway = n
 			}
 		}
 	}
@@ -710,21 +719,3 @@ func (api *RestAPI) getPredictedTimes(
 
 	return predictedArrival, predictedDeparture, true
 }
-
-func (api *RestAPI) getNumberOfStopsAway(ctx context.Context, targetTripID string, targetStopSequence int, vehicle *gtfs.Vehicle, serviceDate time.Time) *int {
-	currentVehicleStopSequence := getCurrentVehicleStopSequence(vehicle)
-	if currentVehicleStopSequence == nil {
-		return nil
-	}
-
-	activeTripID := GetVehicleActiveTripID(vehicle)
-	if activeTripID == "" {
-		activeTripID = targetTripID
-	}
-
-	targetGlobalSeq := api.getBlockSequenceForStopSequence(ctx, targetTripID, targetStopSequence, serviceDate)
-	vehicleGlobalSeq := api.getBlockSequenceForStopSequence(ctx, activeTripID, *currentVehicleStopSequence, serviceDate)
-
-	numberOfStopsAway := targetGlobalSeq - vehicleGlobalSeq - 1
-	return &numberOfStopsAway
-}

internal/restapi/arrival_and_departure_for_stop_handler_test.go

@@ -345,38 +345,6 @@ func TestGetPredictedTimes_EqualArrivalDeparture(t *testing.T) {
 	assert.False(t, predicted)
 }
 
-func TestGetBlockDistanceToStop_NilVehicle(t *testing.T) {
-	api := createTestApi(t)
-	defer api.Shutdown()
-
-	result := api.getBlockDistanceToStop(t.Context(), "test_trip", "test_stop", nil, time.Now())
-
-	assert.Equal(t, 0.0, result)
-}
-
-func TestGetBlockDistanceToStop_NoPosition(t *testing.T) {
-	api := createTestApi(t)
-	defer api.Shutdown()
-	ctx := context.Background()
-
-	vehicle := &gtfs.Vehicle{
-		Position: nil,
-	}
-
-	result := api.getBlockDistanceToStop(ctx, "test_trip", "test_stop", vehicle, time.Now())
-
-	assert.Equal(t, 0.0, result)
-}
-
-func TestGetNumberOfStopsAway_NilCurrentSequence(t *testing.T) {
-	api := createTestApi(t)
-	vehicle := &gtfs.Vehicle{}
-
-	result := api.getNumberOfStopsAway(context.Background(), "test_trip", 5, vehicle, time.Now())
-
-	assert.Nil(t, result)
-}
-
 func TestParseArrivalAndDepartureParams_AllParameters(t *testing.T) {
 	api := createTestApi(t)
 	defer api.Shutdown()
@@ -449,7 +417,7 @@ func TestParseArrivalAndDepartureParams_LargeValues(t *testing.T) {
 
 	assert.Empty(t, errs)
 	assert.Equal(t, 240, params.MinutesAfter)
-	assert.Equal(t, 60, params.MinutesBefore)
+	assert.Equal(t, 240, params.MinutesBefore)
 }
 
 func TestArrivalAndDepartureForStopHandlerWithMalformedID(t *testing.T) {

internal/restapi/arrivals_and_departures_for_stop_handler.go

@@ -2,6 +2,8 @@ package restapi
 
 import (
 	"context"
+	"database/sql"
+	"errors"
 	"log/slog"
 	"net/http"
 	"strconv"
@@ -24,7 +26,8 @@ type ArrivalsStopParams struct {
 
 // parseArrivalsAndDeparturesParams parses and validates parameters.
 func (api *RestAPI) parseArrivalsAndDeparturesParams(r *http.Request) (ArrivalsStopParams, map[string][]string) {
-	const maxBefore = 60 * time.Minute
+	// Both windows cap at 240 min, matching Java and the absence of any spec maximum.
+	const maxBefore = 240 * time.Minute
 	const maxAfter = 240 * time.Minute
 
 	params := ArrivalsStopParams{
@@ -105,7 +108,13 @@ func (api *RestAPI) arrivalsAndDeparturesForStopHandler(w http.ResponseWriter, r
 
 	agency, err := api.GtfsManager.GtfsDB.Queries.GetAgency(ctx, stopAgencyID)
 	if err != nil {
-		api.serverErrorResponse(w, r, err)
+		// Unknown agency (e.g. wrong case in the URL like "hsr_2543" when the
+		// agency_id is "HSR") is a client error — surface 404 instead of 500.
+		if errors.Is(err, sql.ErrNoRows) {
+			api.sendNotFound(w, r)
+		} else {
+			api.serverErrorResponse(w, r, err)
+		}
 		return
 	}
 
@@ -338,61 +347,66 @@ func (api *RestAPI) arrivalsAndDeparturesForStopHandler(w http.ResponseWriter, r
 			predictedDepartureTime = predDep
 		}
 
-		if vehicle != nil {
-			// Use route.AgencyID instead of stopAgencyID for BuildTripStatus
-			status, statusErr := api.BuildTripStatus(ctx, route.AgencyID, st.TripID, nil, serviceMidnight, params.Time)
-			if statusErr != nil {
-				api.Logger.Warn("BuildTripStatus failed for arrival",
-					"tripID", st.TripID, "error", statusErr)
-			}
-			if status != nil {
-				tripStatus = status
+		// Always built — Java attaches a BlockLocation (real-time or scheduled) to
+		// every arrival, so tripStatus is always non-null.
+		status, statusErr := api.BuildTripStatus(ctx, route.AgencyID, st.TripID, nil, serviceMidnight, params.Time)
+		if statusErr != nil {
+			api.Logger.Warn("BuildTripStatus failed for arrival",
+				"tripID", st.TripID, "error", statusErr)
+		}
+		if status != nil {
+			tripStatus = status
 
-				if status.NextStop != "" {
-					_, nextStopID, err := utils.ExtractAgencyIDAndCodeID(status.NextStop)
-					if err == nil {
-						stopIDSet[nextStopID] = true
-					}
+			if status.NextStop != "" {
+				_, nextStopID, err := utils.ExtractAgencyIDAndCodeID(status.NextStop)
+				if err == nil {
+					stopIDSet[nextStopID] = true
 				}
-				if status.ClosestStop != "" {
-					_, closestStopID, err := utils.ExtractAgencyIDAndCodeID(status.ClosestStop)
-					if err == nil {
-						stopIDSet[closestStopID] = true
-					}
+			}
+			if status.ClosestStop != "" {
+				_, closestStopID, err := utils.ExtractAgencyIDAndCodeID(status.ClosestStop)
+				if err == nil {
+					stopIDSet[closestStopID] = true
 				}
+			}
 
-				if vehicle.Position != nil {
-					distanceFromStop = api.getBlockDistanceToStop(ctx, st.TripID, stopCode, vehicle, params.Time)
-
-					numberOfStopsAwayPtr := api.getNumberOfStopsAway(ctx, st.TripID, int(st.StopSequence), vehicle, params.Time)
-					if numberOfStopsAwayPtr != nil {
-						numberOfStopsAway = *numberOfStopsAwayPtr
-					} else {
-						numberOfStopsAway = -1
-					}
+			// Interpolate the block schedule at params.Time−scheduleDeviation.
+			// See GetScheduleDeviationForBlock for the deviation rules.
+			effectiveTime := params.Time
+			if vehicle != nil && vehicle.Trip != nil && vehicle.Trip.ID.ID != "" {
+				blockTripIDs := api.blockTripIDsSortedByStartTime(ctx,
+					api.blockTripIDsForServiceDate(ctx, st.TripID, serviceMidnight))
+				if dev, hasRT := api.GetScheduleDeviationForBlock(ctx, blockTripIDs, serviceMidnight, params.Time); hasRT {
+					effectiveTime = params.Time.Add(-time.Duration(dev) * time.Second)
 				}
+			}
+			if snapshot := api.computeScheduledBlockSnapshot(ctx, st.TripID, effectiveTime, serviceMidnight); snapshot != nil {
+				if d, n, ok := snapshot.metricsForStop(st.TripID, int(st.StopSequence)); ok {
+					distanceFromStop = d
+					numberOfStopsAway = n
+				}
+			}
 
-				// If there's an active trip that's different from the current trip, add it to references
-				if status.ActiveTripID != "" {
-					_, activeTripID, err := utils.ExtractAgencyIDAndCodeID(status.ActiveTripID)
-					if err == nil && activeTripID != st.TripID {
-						// Check cache for active trip
-						if _, exists := tripIDSet[activeTripID]; !exists {
-							activeTrip, err := api.GtfsManager.GtfsDB.Queries.GetTrip(ctx, activeTripID)
-							if err != nil {
-								api.Logger.Debug("skipping active trip reference: trip not found",
-									slog.String("activeTripID", activeTripID),
-									slog.String("scheduledTripID", st.TripID),
-									slog.Any("error", err))
+			// If there's an active trip that's different from the current trip, add it to references
+			if status.ActiveTripID != "" {
+				_, activeTripID, err := utils.ExtractAgencyIDAndCodeID(status.ActiveTripID)
+				if err == nil && activeTripID != st.TripID {
+					// Check cache for active trip
+					if _, exists := tripIDSet[activeTripID]; !exists {
+						activeTrip, err := api.GtfsManager.GtfsDB.Queries.GetTrip(ctx, activeTripID)
+						if err != nil {
+							api.Logger.Debug("skipping active trip reference: trip not found",
+								slog.String("activeTripID", activeTripID),
+								slog.String("scheduledTripID", st.TripID),
+								slog.Any("error", err))
+						} else {
+							tripIDSet[activeTrip.ID] = &activeTrip
+							activeRoute, err := api.GtfsManager.GtfsDB.Queries.GetRoute(ctx, activeTrip.RouteID)
+							if err == nil {
+								routeIDSet[activeRoute.ID] = &activeRoute
 							} else {
-								tripIDSet[activeTrip.ID] = &activeTrip
-								activeRoute, err := api.GtfsManager.GtfsDB.Queries.GetRoute(ctx, activeTrip.RouteID)
-								if err == nil {
-									routeIDSet[activeRoute.ID] = &activeRoute
-								} else {
-									api.Logger.Warn("failed to fetch route for active trip reference",
-										"tripID", activeTripID, "routeID", activeTrip.RouteID, "error", err)
-								}
+								api.Logger.Warn("failed to fetch route for active trip reference",
+									"tripID", activeTripID, "routeID", activeTrip.RouteID, "error", err)
 							}
 						}
 					}