refactor: 拆分前言后记节点 - 提取nodes/foreword.node.ts

server/src/modules/book-generator/nodes/foreword.node.ts

@@ -0,0 +1,47 @@
+/**
+ * 前言后记节点
+ */
+
+import { GraphState } from '../graph';
+import { bookStore } from '../book-generator.store';
+import { callLLMWithMessages } from '../../../services/llm';
+import { FOREWORD_SYSTEM_PROMPT, AFTERWORD_SYSTEM_PROMPT } from '../prompts/templates';
+import { PROGRESS } from '../utils';
+
+/**
+ * 前言生成节点
+ */
+export async function writeForewordNode(state: typeof GraphState.State): Promise<Partial<typeof GraphState.State>> {
+  console.log('[LangGraph] 生成前言, bookId:', state.bookId);
+  try {
+    const messages = [
+      { role: 'system' as const, content: FOREWORD_SYSTEM_PROMPT },
+      { role: 'user' as const, content: `请为《${state.topic}》撰写前言。` },
+    ];
+    const foreword = await callLLMWithMessages(messages);
+    await bookStore.update(state.bookId, { foreword, progress: PROGRESS.FOREWORD_DONE });
+    return { progress: PROGRESS.FOREWORD_DONE };
+  } catch (error) {
+    console.error('[LangGraph] 前言生成失败:', error);
+    return { progress: PROGRESS.FOREWORD_DONE };
+  }
+}
+
+/**
+ * 后记生成节点
+ */
+export async function writeAfterwordNode(state: typeof GraphState.State): Promise<Partial<typeof GraphState.State>> {
+  console.log('[LangGraph] 生成后记, bookId:', state.bookId);
+  try {
+    const messages = [
+      { role: 'system' as const, content: AFTERWORD_SYSTEM_PROMPT },
+      { role: 'user' as const, content: `请为《${state.topic}》撰写后记。` },
+    ];
+    const afterword = await callLLMWithMessages(messages);
+    await bookStore.update(state.bookId, { afterword });
+    return { finished: true, progress: PROGRESS.AFTERWORD_DONE };
+  } catch (error) {
+    console.error('[LangGraph] 后记生成失败:', error);
+    return { finished: true, progress: PROGRESS.AFTERWORD_DONE };
+  }
+}