Remove messageCollection from Conversation model

ts/util/MessageController.ts

@@ -0,0 +1,113 @@
+// Copyright 2019-2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { MessageModel } from '../models/messages';
+
+const SECOND = 1000;
+const MINUTE = SECOND * 60;
+const FIVE_MINUTES = MINUTE * 5;
+const HOUR = MINUTE * 60;
+
+type LookupItemType = {
+  timestamp: number;
+  message: MessageModel;
+};
+type LookupType = Record<string, LookupItemType>;
+
+export class MessageController {
+  private messageLookup: LookupType = Object.create(null);
+
+  private msgIDsBySender = new Map<string, string>();
+
+  private msgIDsBySentAt = new Map<number, string>();
+
+  static install(): MessageController {
+    const instance = new MessageController();
+    window.MessageController = instance;
+
+    instance.startCleanupInterval();
+    return instance;
+  }
+
+  register(id: string, message: MessageModel): MessageModel {
+    if (!id || !message) {
+      return message;
+    }
+
+    const existing = this.messageLookup[id];
+    if (existing) {
+      this.messageLookup[id] = {
+        message: existing.message,
+        timestamp: Date.now(),
+      };
+      return existing.message;
+    }
+
+    this.messageLookup[id] = {
+      message,
+      timestamp: Date.now(),
+    };
+
+    this.msgIDsBySentAt.set(message.get('sent_at'), id);
+    this.msgIDsBySender.set(message.getSenderIdentifier(), id);
+
+    return message;
+  }
+
+  unregister(id: string): void {
+    const { message } = this.messageLookup[id] || {};
+    if (message) {
+      this.msgIDsBySender.delete(message.getSenderIdentifier());
+      this.msgIDsBySentAt.delete(message.get('sent_at'));
+    }
+    delete this.messageLookup[id];
+  }
+
+  cleanup(): void {
+    const messages = Object.values(this.messageLookup);
+    const now = Date.now();
+
+    for (let i = 0, max = messages.length; i < max; i += 1) {
+      const { message, timestamp } = messages[i];
+      const conversation = message.getConversation();
+
+      const state = window.reduxStore.getState();
+      const selectedId = state?.conversations?.selectedConversationId;
+      const inActiveConversation =
+        conversation && selectedId && conversation.id === selectedId;
+
+      if (now - timestamp > FIVE_MINUTES && !inActiveConversation) {
+        this.unregister(message.id);
+      }
+    }
+  }
+
+  getById(id: string): MessageModel | undefined {
+    const existing = this.messageLookup[id];
+    return existing && existing.message ? existing.message : undefined;
+  }
+
+  findBySentAt(sentAt: number): MessageModel | undefined {
+    const id = this.msgIDsBySentAt.get(sentAt);
+    if (!id) {
+      return undefined;
+    }
+    return this.getById(id);
+  }
+
+  findBySender(sender: string): MessageModel | undefined {
+    const id = this.msgIDsBySender.get(sender);
+    if (!id) {
+      return undefined;
+    }
+    return this.getById(id);
+  }
+
+  _get(): LookupType {
+    return this.messageLookup;
+  }
+
+  startCleanupInterval(): NodeJS.Timeout | number {
+    return setInterval(this.cleanup.bind(this), HOUR);
+  }
+}