From f007b72d94563be1803c97cfcb717bfe65a8e5cf Mon Sep 17 00:00:00 2001
From: Brendan Chen <me@bchen.dev>
Date: Thu, 27 Mar 2025 10:19:00 -0700
Subject: [PATCH] add code for in-memory notification repository

---
 .../schedulers/ETANotificationScheduler.ts    |  5 --
 .../InMemoryNotificationRepository.ts         | 65 +++++++++++++++++--
 src/repositories/NotificationRepository.ts    |  2 +-
 3 files changed, 61 insertions(+), 11 deletions(-)

diff --git a/src/notifications/schedulers/ETANotificationScheduler.ts b/src/notifications/schedulers/ETANotificationScheduler.ts
index 0319cf7..385d350 100644
--- a/src/notifications/schedulers/ETANotificationScheduler.ts
+++ b/src/notifications/schedulers/ETANotificationScheduler.ts
@@ -16,11 +16,6 @@ export class ETANotificationScheduler {
     this.sendEtaNotificationImmediately = this.sendEtaNotificationImmediately.bind(this);
     this.etaSubscriberCallback = this.etaSubscriberCallback.bind(this);
     this.sendEtaNotificationImmediatelyIfSecondsRemainingBelowThreshold = this.sendEtaNotificationImmediatelyIfSecondsRemainingBelowThreshold.bind(this);
-    this.scheduleNotification = this.scheduleNotification.bind(this);
-    this.cancelNotificationIfExists = this.cancelNotificationIfExists.bind(this);
-    this.isNotificationScheduled = this.isNotificationScheduled.bind(this);
-    this.getSecondsThresholdForScheduledNotification = this.getSecondsThresholdForScheduledNotification.bind(this);
-    this.getAllScheduledNotificationsForDevice = this.getAllScheduledNotificationsForDevice.bind(this);
   }
 
   /**
diff --git a/src/repositories/InMemoryNotificationRepository.ts b/src/repositories/InMemoryNotificationRepository.ts
index c660ca7..db6e9bc 100644
--- a/src/repositories/InMemoryNotificationRepository.ts
+++ b/src/repositories/InMemoryNotificationRepository.ts
@@ -1,19 +1,74 @@
 import { NotificationLookupArguments, NotificationRepository, ScheduledNotification } from "./NotificationRepository";
+import { TupleKey } from "../types/TupleKey";
+
+type DeviceIdSecondsThresholdAssociation = { [key: string]: number };
 
 export class InMemoryNotificationRepository implements NotificationRepository {
+  /**
+   * An object of device ID arrays to deliver notifications to.
+   * The key should be a combination of the shuttle ID and
+   * stop ID, which can be generated using `TupleKey`.
+   * The value is a dictionary of the device ID to the stored seconds threshold.
+   * @private
+   */
+  private deviceIdsToDeliverTo: { [key: string]: DeviceIdSecondsThresholdAssociation } = {}
+
   async getAllNotificationsForShuttleAndStopId(shuttleId: string, stopId: string) {
-    return [];
+    const tuple = new TupleKey(shuttleId, stopId);
+    if (this.deviceIdsToDeliverTo[tuple.toString()] === undefined) {
+      return [];
+    }
+
+    return Object.keys(this.deviceIdsToDeliverTo[tuple.toString()])
+      .map((deviceId) => {
+        return {
+          shuttleId,
+          stopId,
+          deviceId,
+          secondsThreshold: this.deviceIdsToDeliverTo[tuple.toString()][deviceId]
+        }
+      });
   }
 
-  async getSecondsThresholdForNotificationIfExists(lookupArguments: NotificationLookupArguments) {
-    return 0;
+  async getSecondsThresholdForNotificationIfExists({
+    shuttleId,
+    stopId,
+    deviceId
+  }: NotificationLookupArguments) {
+    const tuple = new TupleKey(shuttleId, stopId);
+    if (this.deviceIdsToDeliverTo[tuple.toString()] === undefined) {
+      return null;
+    }
+    return this.deviceIdsToDeliverTo[tuple.toString()][deviceId];
   }
 
-  async addOrUpdateNotification(notification: ScheduledNotification) {
+  async addOrUpdateNotification({
+    shuttleId,
+    stopId,
+    deviceId,
+    secondsThreshold
+  }: ScheduledNotification) {
+    const tuple = new TupleKey(shuttleId, stopId);
+    if (this.deviceIdsToDeliverTo[tuple.toString()] === undefined) {
+      this.deviceIdsToDeliverTo[tuple.toString()] = {};
+    }
 
+    this.deviceIdsToDeliverTo[tuple.toString()][deviceId] = secondsThreshold;
   }
 
-  async deleteNotificationIfExists(lookupArguments: NotificationLookupArguments) {
+  async deleteNotificationIfExists({
+    deviceId,
+    shuttleId,
+    stopId
+  }: NotificationLookupArguments) {
+    const tupleKey = new TupleKey(shuttleId, stopId);
+    if (
+      this.deviceIdsToDeliverTo[tupleKey.toString()] === undefined
+      || !(deviceId in this.deviceIdsToDeliverTo[tupleKey.toString()])
+    ) {
+      return;
+    }
 
+    delete this.deviceIdsToDeliverTo[tupleKey.toString()][deviceId];
   }
 }
diff --git a/src/repositories/NotificationRepository.ts b/src/repositories/NotificationRepository.ts
index 3787f3d..343497e 100644
--- a/src/repositories/NotificationRepository.ts
+++ b/src/repositories/NotificationRepository.ts
@@ -16,7 +16,7 @@ export interface ScheduledNotification extends NotificationLookupArguments {
 
 export interface NotificationRepository {
   getAllNotificationsForShuttleAndStopId(shuttleId: string, stopId: string): Promise<ScheduledNotification[]>;
-  getSecondsThresholdForNotificationIfExists(lookupArguments: NotificationLookupArguments): Promise<number>;
+  getSecondsThresholdForNotificationIfExists(lookupArguments: NotificationLookupArguments): Promise<number | null>;
   addOrUpdateNotification(notification: ScheduledNotification): Promise<void>;
   deleteNotificationIfExists(lookupArguments: NotificationLookupArguments): Promise<void>;
 }