refactor: extract gateway transcript append helper

src/gateway/server-methods/chat.ts

@@ -1,6 +1,6 @@
 import fs from "node:fs";
 import path from "node:path";
-import { CURRENT_SESSION_VERSION, SessionManager } from "@mariozechner/pi-coding-agent";
+import { CURRENT_SESSION_VERSION } from "@mariozechner/pi-coding-agent";
 import { resolveSessionAgentId } from "../../agents/agent-scope.js";
 import { resolveThinkingDefault } from "../../agents/model-selection.js";
 import { resolveAgentTimeoutMs } from "../../agents/timeout.js";
@@ -45,6 +45,7 @@ import {
 import { formatForLog } from "../ws-log.js";
 import { injectTimestamp, timestampOptsFromConfig } from "./agent-timestamp.js";
 import { normalizeRpcAttachmentsToChatAttachments } from "./attachment-normalize.js";
+import { appendInjectedAssistantMessageToTranscript } from "./chat-transcript-inject.js";
 import type { GatewayRequestContext, GatewayRequestHandlers } from "./types.js";
 
 type TranscriptAppendResult = {
@@ -54,7 +55,6 @@ type TranscriptAppendResult = {
   error?: string;
 };
 
-type AppendMessageArg = Parameters<SessionManager["appendMessage"]>[0];
 type AbortOrigin = "rpc" | "stop-command";
 
 type AbortedPartialSnapshot = {
@@ -376,55 +376,13 @@ function appendAssistantTranscriptMessage(params: {
     return { ok: true };
   }
 
-  const now = Date.now();
-  const labelPrefix = params.label ? `[${params.label}]\n\n` : "";
-  const usage = {
-    input: 0,
-    output: 0,
-    cacheRead: 0,
-    cacheWrite: 0,
-    totalTokens: 0,
-    cost: {
-      input: 0,
-      output: 0,
-      cacheRead: 0,
-      cacheWrite: 0,
-      total: 0,
-    },
-  };
-  const messageBody: AppendMessageArg & Record<string, unknown> = {
-    role: "assistant",
-    content: [{ type: "text", text: `${labelPrefix}${params.message}` }],
-    timestamp: now,
-    // Pi stopReason is a strict enum; this is not model output, but we still store it as a
-    // normal assistant message so it participates in the session parentId chain.
-    stopReason: "stop",
-    usage,
-    // Make these explicit so downstream tooling never treats this as model output.
-    api: "openai-responses",
-    provider: "openclaw",
-    model: "gateway-injected",
-    ...(params.idempotencyKey ? { idempotencyKey: params.idempotencyKey } : {}),
-    ...(params.abortMeta
-      ? {
-          openclawAbort: {
-            aborted: true,
-            origin: params.abortMeta.origin,
-            runId: params.abortMeta.runId,
-          },
-        }
-      : {}),
-  };
-
-  try {
-    // IMPORTANT: Use SessionManager so the entry is attached to the current leaf via parentId.
-    // Raw jsonl appends break the parent chain and can hide compaction summaries from context.
-    const sessionManager = SessionManager.open(transcriptPath);
-    const messageId = sessionManager.appendMessage(messageBody);
-    return { ok: true, messageId, message: messageBody };
-  } catch (err) {
-    return { ok: false, error: err instanceof Error ? err.message : String(err) };
-  }
+  return appendInjectedAssistantMessageToTranscript({
+    transcriptPath,
+    message: params.message,
+    label: params.label,
+    idempotencyKey: params.idempotencyKey,
+    abortMeta: params.abortMeta,
+  });
 }
 
 function collectSessionAbortPartials(params: {