refactor: unify reply dispatch across providers

src/auto-reply/reply/reply-dispatcher.ts

@@ -0,0 +1,99 @@
+import { stripHeartbeatToken } from "../heartbeat.js";
+import { HEARTBEAT_TOKEN, SILENT_REPLY_TOKEN } from "../tokens.js";
+import type { ReplyPayload } from "../types.js";
+
+export type ReplyDispatchKind = "tool" | "block" | "final";
+
+type ReplyDispatchErrorHandler = (
+  err: unknown,
+  info: { kind: ReplyDispatchKind },
+) => void;
+
+type ReplyDispatchDeliverer = (
+  payload: ReplyPayload,
+  info: { kind: ReplyDispatchKind },
+) => Promise<void>;
+
+export type ReplyDispatcherOptions = {
+  deliver: ReplyDispatchDeliverer;
+  responsePrefix?: string;
+  onHeartbeatStrip?: () => void;
+  onError?: ReplyDispatchErrorHandler;
+};
+
+type ReplyDispatcher = {
+  sendToolResult: (payload: ReplyPayload) => boolean;
+  sendBlockReply: (payload: ReplyPayload) => boolean;
+  sendFinalReply: (payload: ReplyPayload) => boolean;
+  waitForIdle: () => Promise<void>;
+  getQueuedCounts: () => Record<ReplyDispatchKind, number>;
+};
+
+function normalizeReplyPayload(
+  payload: ReplyPayload,
+  opts: Pick<ReplyDispatcherOptions, "responsePrefix" | "onHeartbeatStrip">,
+): ReplyPayload | null {
+  const hasMedia = Boolean(
+    payload.mediaUrl || (payload.mediaUrls?.length ?? 0) > 0,
+  );
+  const trimmed = payload.text?.trim() ?? "";
+  if (!trimmed && !hasMedia) return null;
+
+  // Avoid sending the explicit silent token when no media is attached.
+  if (trimmed === SILENT_REPLY_TOKEN && !hasMedia) return null;
+
+  let text = payload.text ?? undefined;
+  if (text && !trimmed) {
+    // Keep empty text when media exists so media-only replies still send.
+    text = "";
+  }
+  if (text?.includes(HEARTBEAT_TOKEN)) {
+    const stripped = stripHeartbeatToken(text, { mode: "message" });
+    if (stripped.didStrip) opts.onHeartbeatStrip?.();
+    if (stripped.shouldSkip && !hasMedia) return null;
+    text = stripped.text;
+  }
+
+  if (
+    opts.responsePrefix &&
+    text &&
+    text.trim() !== HEARTBEAT_TOKEN &&
+    !text.startsWith(opts.responsePrefix)
+  ) {
+    text = `${opts.responsePrefix} ${text}`;
+  }
+
+  return { ...payload, text };
+}
+
+export function createReplyDispatcher(
+  options: ReplyDispatcherOptions,
+): ReplyDispatcher {
+  let sendChain: Promise<void> = Promise.resolve();
+  // Serialize outbound replies to preserve tool/block/final order.
+  const queuedCounts: Record<ReplyDispatchKind, number> = {
+    tool: 0,
+    block: 0,
+    final: 0,
+  };
+
+  const enqueue = (kind: ReplyDispatchKind, payload: ReplyPayload) => {
+    const normalized = normalizeReplyPayload(payload, options);
+    if (!normalized) return false;
+    queuedCounts[kind] += 1;
+    sendChain = sendChain
+      .then(() => options.deliver(normalized, { kind }))
+      .catch((err) => {
+        options.onError?.(err, { kind });
+      });
+    return true;
+  };
+
+  return {
+    sendToolResult: (payload) => enqueue("tool", payload),
+    sendBlockReply: (payload) => enqueue("block", payload),
+    sendFinalReply: (payload) => enqueue("final", payload),
+    waitForIdle: () => sendChain,
+    getQueuedCounts: () => ({ ...queuedCounts }),
+  };
+}