Chat system refactor

packages/app/src/chat/index.ts

@@ -0,0 +1,90 @@
+import { useSyncExternalStore } from "react";
+import { Nip4ChatSystem } from "./nip4";
+import { EventKind, EventPublisher, NostrEvent, RequestBuilder, SystemInterface, UserMetadata } from "@snort/system";
+import { unwrap } from "@snort/shared";
+import { Chats } from "Cache";
+import { findTag, unixNow } from "SnortUtils";
+import { Nip29ChatSystem } from "./nip29";
+
+export enum ChatType {
+  DirectMessage = 1,
+  PublicGroupChat = 2,
+  PrivateGroupChat = 3,
+}
+
+export interface Chat {
+  type: ChatType;
+  id: string;
+  unread: number;
+  lastMessage: number;
+  messages: Array<NostrEvent>;
+  profile?: UserMetadata;
+  createMessage(msg: string, pub: EventPublisher): Promise<NostrEvent>;
+  sendMessage(ev: NostrEvent, system: SystemInterface): void | Promise<void>;
+}
+
+export interface ChatSystem {
+  /**
+   * Create a request for this system to get updates
+   */
+  subscription(id: string): RequestBuilder | undefined;
+  onEvent(evs: Array<NostrEvent>): Promise<void> | void;
+
+  listChats(): Array<Chat>;
+}
+
+export const Nip4Chats = new Nip4ChatSystem(Chats);
+export const Nip29Chats = new Nip29ChatSystem(Chats);
+
+/**
+ * Extract the P tag of the event
+ */
+export function chatTo(e: NostrEvent) {
+  if (e.kind === EventKind.DirectMessage) {
+    return unwrap(findTag(e, "p"));
+  } else if (e.kind === EventKind.SimpleChatMessage) {
+    const gt = unwrap(e.tags.find(a => a[0] === "g"));
+    return `${gt[2]}${gt[1]}`;
+  }
+  throw new Error("Not a chat message");
+}
+
+export function inChatWith(e: NostrEvent, myPk: string) {
+  if (e.pubkey === myPk) {
+    return chatTo(e);
+  } else {
+    return e.pubkey;
+  }
+}
+
+export function lastReadInChat(id: string) {
+  const k = `dm:seen:${id}`;
+  return parseInt(window.localStorage.getItem(k) ?? "0");
+}
+
+export function setLastReadIn(id: string) {
+  const now = unixNow();
+  const k = `dm:seen:${id}`;
+  window.localStorage.setItem(k, now.toString());
+}
+
+export function useNip4Chat() {
+  return useSyncExternalStore(
+    c => Nip4Chats.hook(c),
+    () => Nip4Chats.snapshot()
+  );
+}
+
+export function useNip29Chat() {
+  return useSyncExternalStore(
+    c => Nip29Chats.hook(c),
+    () => Nip29Chats.snapshot()
+  );
+}
+
+export function useChatSystem() {
+  const nip4 = useNip4Chat();
+  const nip29 = useNip29Chat();
+
+  return [...nip4, ...nip29];
+}