Fix training plan generation flow

server/routers.ts

@@ -8,6 +8,50 @@ import { invokeLLM } from "./_core/llm";
 import { storagePut } from "./storage";
 import * as db from "./db";
 import { nanoid } from "nanoid";
+import {
+  normalizeAdjustedPlanResponse,
+  normalizeTrainingPlanResponse,
+} from "./trainingPlan";
+
+async function invokeStructuredPlan<T>(params: {
+  baseMessages: Array<{ role: "system" | "user"; content: string }>;
+  responseFormat: {
+    type: "json_schema";
+    json_schema: {
+      name: string;
+      strict: true;
+      schema: Record<string, unknown>;
+    };
+  };
+  parse: (content: unknown) => T;
+}) {
+  let lastError: unknown;
+
+  for (let attempt = 0; attempt < 3; attempt++) {
+    const retryHint =
+      attempt === 0 || !(lastError instanceof Error)
+        ? []
+        : [{
+            role: "user" as const,
+            content:
+              `上一次输出无法被系统解析，错误是：${lastError.message}。` +
+              "请只返回一个合法、完整、可解析的 JSON 对象，不要包含额外说明、注释或 Markdown 代码块。",
+          }];
+
+    const response = await invokeLLM({
+      messages: [...params.baseMessages, ...retryHint],
+      response_format: params.responseFormat,
+    });
+
+    try {
+      return params.parse(response.choices[0]?.message?.content);
+    } catch (error) {
+      lastError = error;
+    }
+  }
+
+  throw lastError instanceof Error ? lastError : new Error("Failed to parse structured LLM response");
+}
 
 export const appRouter = router({
   system: systemRouter,
@@ -85,12 +129,12 @@ ${recentScores.length > 0 ? `- 用户最近的分析数据: ${JSON.stringify(rec
 
 请返回JSON格式，包含每天的训练内容。`;
 
-        const response = await invokeLLM({
-          messages: [
+        const parsed = await invokeStructuredPlan({
+          baseMessages: [
             { role: "system", content: "你是网球训练计划生成器。返回严格的JSON格式。" },
             { role: "user", content: prompt },
           ],
-          response_format: {
+          responseFormat: {
             type: "json_schema",
             json_schema: {
               name: "training_plan",
@@ -123,12 +167,12 @@ ${recentScores.length > 0 ? `- 用户最近的分析数据: ${JSON.stringify(rec
               },
             },
           },
+          parse: (content) => normalizeTrainingPlanResponse({
+            content,
+            fallbackTitle: `${input.durationDays}天训练计划`,
+          }),
         });
 
-        const content = response.choices[0]?.message?.content;
-        const parsed = typeof content === "string" ? JSON.parse(content) : null;
-        if (!parsed) throw new Error("Failed to generate training plan");
-
         const planId = await db.createTrainingPlan({
           userId: user.id,
           title: parsed.title,
@@ -173,12 +217,12 @@ ${recentScores.length > 0 ? `- 用户最近的分析数据: ${JSON.stringify(rec
 
 请根据分析结果调整训练计划，增加针对薄弱环节的训练，返回与原计划相同格式的JSON。`;
 
-        const response = await invokeLLM({
-          messages: [
-            { role: "system", content: "你是网球评分生成器。返回严格的JSON格式。" },
+        const parsed = await invokeStructuredPlan({
+          baseMessages: [
+            { role: "system", content: "你是网球训练计划调整器。返回严格的JSON格式。" },
             { role: "user", content: prompt },
           ],
-          response_format: {
+          responseFormat: {
             type: "json_schema",
             json_schema: {
               name: "adjusted_plan",
@@ -212,12 +256,12 @@ ${recentScores.length > 0 ? `- 用户最近的分析数据: ${JSON.stringify(rec
               },
             },
           },
+          parse: (content) => normalizeAdjustedPlanResponse({
+            content,
+            fallbackTitle: currentPlan.title,
+          }),
         });
 
-        const content = response.choices[0]?.message?.content;
-        const parsed = typeof content === "string" ? JSON.parse(content) : null;
-        if (!parsed) throw new Error("Failed to adjust plan");
-
         await db.updateTrainingPlan(input.planId, {
           exercises: parsed.exercises,
           adjustmentNotes: parsed.adjustmentNotes,