Implement getShuttleLastStopArrival and updateShuttleLastStopArrival

src/repositories/shuttle/RedisShuttleRepository.ts

@@ -105,6 +105,7 @@ export class RedisShuttleRepository extends EventEmitter implements ShuttleGette
   private createShuttleKey = (shuttleId: string) => `shuttle:shuttle:${shuttleId}`;
   private createEtaKey = (shuttleId: string, stopId: string) => `shuttle:eta:${shuttleId}:${stopId}`;
   private createOrderedStopKey = (routeId: string, stopId: string) => `shuttle:orderedstop:${routeId}:${stopId}`;
+  private createShuttleLastStopKey = (shuttleId: string) => `shuttle:laststop:${shuttleId}`;
 
   // Helper methods for converting entities to Redis hashes
   private createRedisHashFromStop = (stop: IStop): Record<string, string> => ({
@@ -453,13 +454,25 @@ export class RedisShuttleRepository extends EventEmitter implements ShuttleGette
   }
 
   public async getShuttleLastStopArrival(shuttle: IShuttle): Promise<ShuttleStopArrival | undefined> {
-    // Get the *time* of the most recent time series entry for the key 
-    throw Error("not implemented");
+    const key = this.createShuttleLastStopKey(shuttle.id);
+    const data = await this.redisClient.hGetAll(key);
+
+    if (Object.keys(data).length === 0) {
+      return undefined;
+    }
+
+    return {
+      stopId: data.stopId,
+      timestamp: new Date(data.timestamp),
+    };
   }
 
   public async updateShuttleLastStopArrival(shuttle: IShuttle, lastStopArrival: ShuttleStopArrival) {
-    // Key: shuttleId:stopId:
-    // Value: just a marker (no numerical value)
+    const key = this.createShuttleLastStopKey(shuttle.id);
+    await this.redisClient.hSet(key, {
+      stopId: lastStopArrival.stopId,
+      timestamp: lastStopArrival.timestamp.toISOString(),
+    });
   }
 
    public async addOrUpdateStop(stop: IStop): Promise<void> {