refactor: migrate from pnpm workspaces to single-package structure with shared types

backend/src/ingestion/youtubei.ts

@@ -0,0 +1,153 @@
+import type { ChatMessage } from '@shared/chat';
+import EventEmitter from 'eventemitter3';
+import Innertube, { UniversalCache } from 'youtubei.js';
+
+export type IngestionContext = {
+  client: Innertube;
+  liveChat: any;
+  videoId: string;
+  emitter: ChatEventEmitter;
+};
+
+export type ContinuationState = {
+  messages: ChatMessage[];
+  nextToken: string | null;
+  timeoutMs: number;
+};
+
+export type ChatEventEmitter = EventEmitter<{
+  message: (message: ChatMessage) => void;
+  error: (error: unknown) => void;
+}>;
+
+const defaultTimeout = 1500;
+
+export async function bootstrapInnertube(videoId: string): Promise<IngestionContext> {
+  if (!videoId) {
+    throw new Error('YOUTUBE_LIVE_ID is required to bootstrap Innertube');
+  }
+
+  console.log('[Ingestion] Creating Innertube client...');
+  const client = await Innertube.create({
+    cache: new UniversalCache(false)
+  });
+
+  console.log('[Ingestion] Fetching video info...');
+  const info = await client.getInfo(videoId);
+  
+  console.log('[Ingestion] Getting live chat...');
+  const liveChat = info.getLiveChat();
+
+  if (!liveChat) {
+    throw new Error('This video does not have an active live chat');
+  }
+
+  const emitter: ChatEventEmitter = new EventEmitter();
+
+  liveChat.on('chat-update', (action: any) => {
+    const normalized = normalizeAction(action);
+    if (normalized) {
+      emitter.emit('message', normalized);
+    }
+  });
+
+  liveChat.on('error', (err: unknown) => {
+    console.error('[Ingestion] Live chat error:', err);
+    emitter.emit('error', err);
+  });
+
+  console.log('[Ingestion] Starting live chat listener...');
+  liveChat.start();
+  console.log('[Ingestion] Live chat listener started');
+
+  return {
+    client,
+    liveChat,
+    videoId,
+    emitter
+  };
+}
+
+export async function fetchChatBatch(
+  ctx: IngestionContext,
+  options?: { windowMs?: number }
+): Promise<ContinuationState> {
+  const windowMs = options?.windowMs ?? defaultTimeout;
+  const collected: ChatMessage[] = [];
+
+  const listener = (message: ChatMessage) => {
+    collected.push(message);
+  };
+
+  ctx.emitter.on('message', listener);
+
+  await delay(windowMs);
+
+  ctx.emitter.off('message', listener);
+
+  return {
+    messages: collected,
+    nextToken: ctx.liveChat?.continuation?.token ?? null,
+    timeoutMs: ctx.liveChat?.continuation?.timeout_ms ?? defaultTimeout
+  };
+}
+
+function resolveMessageText(item: any): string {
+  if (!item?.message) return '';
+
+  if (typeof item.message === 'string') {
+    return item.message;
+  }
+
+  if (typeof item.message?.toString === 'function') {
+    return item.message.toString();
+  }
+
+  if (Array.isArray(item.message?.runs)) {
+    return item.message.runs.map((run: any) => run.text ?? '').join('');
+  }
+
+  return '';
+}
+
+function resolveTimestamp(timestamp: number | string | undefined): string {
+  if (!timestamp) {
+    return new Date().toISOString();
+  }
+
+  const numeric = typeof timestamp === 'string' ? Number(timestamp) : timestamp;
+  if (Number.isFinite(numeric)) {
+    const millis = numeric > 1e12 ? numeric / 1000 : numeric;
+    return new Date(millis).toISOString();
+  }
+
+  return new Date().toISOString();
+}
+
+function normalizeAction(action: any): ChatMessage | null {
+  if (!action || action.type !== 'AddChatItemAction') {
+    return null;
+  }
+
+  const item = action.item;
+  if (!item) return null;
+
+  if (
+    item.type === 'LiveChatTextMessage' ||
+    item.type === 'LiveChatPaidMessage' ||
+    item.type === 'LiveChatMembershipItem'
+  ) {
+    return {
+      id: String(item.id ?? item.timestamp_usec ?? Date.now()),
+      author: String(item.author?.name ?? 'Unknown'),
+      text: resolveMessageText(item),
+      publishedAt: resolveTimestamp(item.timestamp ?? item.timestamp_usec)
+    };
+  }
+
+  return null;
+}
+
+function delay(ms: number) {
+  return new Promise((resolve) => setTimeout(resolve, ms));
+}