cleanup

subscriptionMap.ts

@@ -0,0 +1,50 @@
+import { WS } from "./index";
+
+export class SubscriptionMap {
+  private channelsPerClient = new Map<WS, Set<string>>();
+  private clientsPerChannel = new Map<string, Set<WS>>();
+
+  // prepare
+  private prepareChannelSet(ws: WS) {
+    if (this.channelsPerClient.has(ws)) return;
+    this.channelsPerClient.set(ws, new Set());
+  }
+
+  private prepareClientSet(channel: string) {
+    if (this.clientsPerChannel.has(channel)) return;
+    this.clientsPerChannel.set(channel, new Set());
+  }
+
+  // utility
+  getChannelList(ws: WS) {
+    return this.channelsPerClient.get(ws);
+  }
+
+  getClientList(channel: string) {
+    return this.clientsPerChannel.get(channel);
+  }
+
+  // modifications
+  set(ws: WS, channel: string) {
+    this.prepareChannelSet(ws);
+    this.prepareClientSet(channel);
+
+    this.getChannelList(ws)?.add(channel);
+    this.getClientList(channel)?.add(ws);
+  }
+
+  delete(ws: WS, channel: string) {
+    const channelList = this.getChannelList(ws);
+    const clientList = this.getClientList(channel);
+
+    channelList?.delete(channel);
+    if (channelList?.size == 0) {
+      this.channelsPerClient.delete(ws);
+    }
+
+    clientList?.delete(ws);
+    if (clientList?.size == 0) {
+      this.clientsPerChannel.delete(channel);
+    }
+  }
+}