/**
 * LangGraph 书籍生成 - API 路由
 * 支持书籍创建时的预估显示
 */

import Router from '@koa/router';
import { Context } from 'koa';
import { langGraphGenerator, getScaleConfig } from './index';
import { queueService, QueueType } from '../../services/queue.service';
import { bookStore } from './book-generator.store';
import { estimateBookWords, estimateAudioMinutesFromWords, checkBookGenerationQuota } from '../subscription/subscription.service';
import { optionalAuth } from '../../middleware/auth';
import { getAllBookTypes, getDetectableTypes, getBookTypeConfig, BOOK_TYPE_CONFIG, DETECTABLE_TYPES } from './book-type-config';
import { callLLMWithMessages, ChatMessage } from '../../services/llm';
import { createVideoProjectFromBook, generateVideoForProject } from '../video-generator/video-generator.service';

// 开发环境测试用户ID
const TEST_USER_ID = '1';

const router = new Router();

/**
 * GET /api/book-generator/langgraph/estimate
 * 获取书籍规模预估信息
 */
router.get('/estimate', async (ctx: Context) => {
  const { scale, userId } = ctx.query as { scale?: string; userId?: string };
  
  if (!scale) {
    ctx.status = 400;
    ctx.body = { code: 1, message: '请提供书籍规模' };
    return;
  }

  const scaleConfig = getScaleConfig(scale);
  const avgWords = Math.round((scaleConfig.wordRange.min + scaleConfig.wordRange.max) / 2);
  const audioMinutes = estimateAudioMinutesFromWords(avgWords);
  const estimatedChapters = Math.round((scaleConfig.chapterRange.min + scaleConfig.chapterRange.max) / 2);

  const result: any = {
    scale,
    scaleConfig,
    audioMinutes: {
      min: estimateAudioMinutesFromWords(scaleConfig.wordRange.min),
      max: estimateAudioMinutesFromWords(scaleConfig.wordRange.max),
      avg: audioMinutes
    },
    estimatedChapters
  };
  
  // 如果提供了 userId，同时检查用户配额
  if (userId) {
    const quotaCheck = await checkBookGenerationQuota(parseInt(userId), scale);
    result.quotaCheck = quotaCheck;
  }
  
  ctx.body = {
    code: 0,
    message: 'success',
    data: result
  };
});

/**
 * GET /api/book-generator/langgraph/book-types
 * 获取所有书籍类型配置（供前端显示）
 */
router.get('/book-types', async (ctx: Context) => {
  const types = getAllBookTypes().map(t => ({
    key: t.key,
    label: t.label,
    description: t.description,
    chapters: t.chapters,
    totalWords: t.totalWords,
    chapterWords: t.chapterWords,
    sectionWords: t.sectionWords,
    structureFormat: t.structureFormat,
    readingDifficulty: t.readingDifficulty,
    isShortArticle: t.isShortArticle,
  }));

  ctx.body = {
    code: 0,
    message: 'success',
    data: types,
  };
});

/**
 * POST /api/book-generator/langgraph/detect-book-type
 * AI 自动检测书籍类型
 */
router.post('/detect-book-type', async (ctx: Context) => {
  const { title, description } = ctx.request.body as {
    title?: string;
    description?: string;
  };

  if (!title) {
    ctx.status = 400;
    ctx.body = { code: 1, message: '请提供书籍标题' };
    return;
  }

  const detectableTypes = DETECTABLE_TYPES;

  // 构建类型特征描述，帮助 AI 分类
  const typeDescriptions = detectableTypes.map(key => {
    const t = BOOK_TYPE_CONFIG[key];
    return `- ${t.key}: ${t.description}，${t.chapters.min}-${t.chapters.max}章，总字数${t.totalWords.min}-${t.totalWords.max}字，每章约${t.chapterWords}字，结构形式：${t.structureFormat}，阅读难度：${t.readingDifficulty}`;
  }).join('\n');

  const messages: ChatMessage[] = [
    {
      role: 'system',
      content: `你是一位专业的图书分类编辑。根据用户提供的标题和描述，判断这本书最可能属于以下哪种类型：

可选类型：
${typeDescriptions}

## 分类规则
1. 分析标题中的关键词（如"科普""青少年""专业""小说"等）
2. 分析描述中的目标读者、写作风格、内容深度
3. 匹配最符合的类型

## 输出格式
必须返回 JSON，不要包含 markdown 代码块标记：
{
  "detectedType": "类型 key",
  "confidence": 0.85,
  "reasoning": "分类理由，1-2句话"
}

confidence 是 0-1 的数值，表示置信程度。`,
    },
    {
      role: 'user',
      content: `标题：《${title}》\n描述：${description || '无'}`,
    },
  ];

  try {
    const response = await callLLMWithMessages(messages);
    const parsed = parseDetectResult(response);

    if (!parsed) {
      // 降级到关键词匹配
      const fallback = keywordFallback(title, description || '');
      ctx.body = {
        code: 0,
        message: 'success',
        data: {
          detectedType: fallback.detectedType,
          confidence: 0.5,
          reasoning: '基于关键词匹配（AI 解析失败，使用降级策略）',
          config: getBookTypeConfig(fallback.detectedType),
        },
      };
      return;
    }

    ctx.body = {
      code: 0,
      message: 'success',
      data: {
        detectedType: parsed.detectedType,
        confidence: parsed.confidence,
        reasoning: parsed.reasoning,
        config: getBookTypeConfig(parsed.detectedType),
      },
    };
  } catch (error: any) {
    // 最终降级：关键词匹配
    const fallback = keywordFallback(title, description || '');
    ctx.body = {
      code: 0,
      message: 'success',
      data: {
        detectedType: fallback.detectedType,
        confidence: 0.3,
        reasoning: 'LLM 调用失败，使用关键词匹配降级',
        config: getBookTypeConfig(fallback.detectedType),
      },
    };
  }
});

function parseDetectResult(text: string): { detectedType: string; confidence: number; reasoning: string } | null {
  try {
    const match = text.match(/\{[\s\S]*\}/);
    if (!match) return null;
    const data = JSON.parse(match[0]);
    if (!data.detectedType) return null;
    // 验证类型是否有效
    if (!DETECTABLE_TYPES.includes(data.detectedType)) {
      // 尝试模糊匹配
      const found = DETECTABLE_TYPES.find(t => data.detectedType.includes(t) || t.includes(data.detectedType));
      if (!found) return null;
      data.detectedType = found;
    }
    return {
      detectedType: data.detectedType,
      confidence: Math.min(1, Math.max(0, data.confidence || 0.5)),
      reasoning: data.reasoning || '',
    };
  } catch {
    return null;
  }
}

function keywordFallback(title: string, description: string): { detectedType: string } {
  const text = `${title} ${description}`.toLowerCase();

  if (text.includes('小说') || text.includes('故事') || text.includes('fiction')) {
    if (text.includes('网络') || text.includes('连载') || text.includes('修仙') || text.includes('穿越')) {
      return { detectedType: '网络小说' };
    }
    return { detectedType: '现代出版长篇小说' };
  }
  if (text.includes('科普') || text.includes('经管') || text.includes('畅销') || text.includes('通俗')) {
    return { detectedType: '科普经管畅销书' };
  }
  if (text.includes('专业') || text.includes('大学') || text.includes('研究生') || text.includes('算法') || text.includes('操作系统') || text.includes('数据库')) {
    return { detectedType: '大学专业教材' };
  }
  if (text.includes('中小学') || text.includes('初中') || text.includes('高中') || text.includes('青少年') || text.includes('儿童')) {
    return { detectedType: '中小学课本' };
  }
  if (text.includes('古典') || text.includes('章回') || text.includes('名著') || text.includes('红楼') || text.includes('西游') || text.includes('三国') || text.includes('水浒')) {
    return { detectedType: '古典名著' };
  }

  return { detectedType: '中小学课本' }; // 默认
}

/**
 * AI 自动检测书籍类型（后端静默调用，前端无感知）
 */
async function autoDetectBookType(title: string, description: string): Promise<string> {
  const detectableTypes = DETECTABLE_TYPES;
  const typeDescriptions = detectableTypes.map(key => {
    const t = BOOK_TYPE_CONFIG[key];
    return `- ${t.key}: ${t.description}，${t.chapters.min}-${t.chapters.max}章，总字数${t.totalWords.min}-${t.totalWords.max}字`;
  }).join('\n');

  const messages: ChatMessage[] = [
    {
      role: 'system',
      content: `你是一位专业的图书分类编辑。根据标题和描述，判断书籍属于以下哪种类型：

可选类型：
${typeDescriptions}

分类规则：
1. 分析标题中的关键词（如"科普""青少年""专业""小说"等）
2. 分析描述中的目标读者、写作风格、内容深度
3. 匹配最符合的类型

输出格式：只返回类型 key，不要其他内容。`,
    },
    {
      role: 'user',
      content: `标题：《${title}》\n描述：${description}`,
    },
  ];

  try {
    const response = await callLLMWithMessages(messages);
    const trimmed = response.trim();
    if (detectableTypes.includes(trimmed)) return trimmed;
    const found = detectableTypes.find(t => trimmed.includes(t) || t.includes(trimmed));
    if (found) return found;
    return keywordFallback(title, description).detectedType;
  } catch {
    return keywordFallback(title, description).detectedType;
  }
}

/**
 * POST /api/book-generator/langgraph/books
 * 使用 LangGraph 创建并生成书籍（异步，自动生成大纲和内容）
 * AI 根据标题+描述自动判断书籍类型
 */
router.post('/books', async (ctx: Context) => {
  try {
    const body = ctx.request.body as {
      title: string;
      description: string;
      bookScale?: string;
      generateForeword?: boolean;
      generateAfterword?: boolean;
    };

    if (!body.title || !body.description) {
      ctx.status = 400;
      ctx.body = { code: 1, message: '书名和描述不能为空' };
      return;
    }

    // AI 自动检测书籍类型（如果前端传了 bookScale 则用前端的，否则自动检测）
    let bookScale = body.bookScale;
    if (!bookScale) {
      const detectResult = await autoDetectBookType(body.title, body.description);
      bookScale = detectResult;
      console.log(`[LangGraph] AI 自动检测类型: ${body.title} -> ${bookScale}`);
    }

    // 创建书籍（预估章节数，实际数量由AI根据字数范围分析后确定）
    const scaleConfig = getScaleConfig(bookScale);
    const estimatedChapters = Math.round((scaleConfig.chapterRange.min + scaleConfig.chapterRange.max) / 2);
    const book = await bookStore.create({
      title: body.title,
      description: body.description,
      bookScale: bookScale,
      totalChapters: estimatedChapters,
    });

    // 尝试将生成任务加入队列（队列只是为了改善用户体验）
    try {
      const jobId = await queueService.addBookGenerationTask({
        bookId: book.id,
        topic: body.description,
        bookScale,
      });
      console.log(`[LangGraph] 生成任务已加入队列: bookId=${book.id}, jobId=${jobId}`);
      
      ctx.body = {
        code: 0,
        message: '书籍创建成功，生成已开始（队列模式）',
        data: {
          book,
          jobId,
          status: 'generating',
          mode: 'queue',
        },
      };
    } catch (queueError) {
      // 队列失败时，降级为同步执行（确保核心业务不受影响）
      console.warn(`[LangGraph] 队列不可用，降级为同步执行: bookId=${book.id}`, queueError);
      
      try {
        // 同步调用生成器，等待完成
        await langGraphGenerator.generate(book.id.toString(), body.description, bookScale);
        
        console.log(`[LangGraph] 同步执行完成: bookId=${book.id}`);
        
        ctx.body = {
          code: 0,
          message: '书籍创建成功，生成已完成（同步模式）',
          data: {
            book,
            status: 'completed',
            mode: 'sync',
          },
        };
      } catch (generateError) {
        // 生成失败，更新书籍状态
        console.error(`[LangGraph] 同步执行失败: bookId=${book.id}`, generateError);
        await bookStore.update(book.id.toString(), {
          status: 'failed',
          errorMsg: generateError instanceof Error ? generateError.message : '生成失败',
        });
        
        ctx.body = {
          code: 0,
          message: '书籍创建成功，但生成失败',
          data: {
            book,
            status: 'failed',
            mode: 'sync',
            error: generateError instanceof Error ? generateError.message : '生成失败',
          },
        };
      }
    }
  } catch (error) {
    console.error('启动失败:', error);
    ctx.status = 500;
    ctx.body = {
      code: 1,
      message: error instanceof Error ? error.message : '启动失败',
    };
  }
});

/**
 * GET /api/book-generator/langgraph/books
 * 获取书籍列表
 * 返回：公开的书籍（有公开音频）+ 当前用户自己的书籍
 * 注意：此接口已废弃，请使用 /public-books 或 /my-books
 */
router.get('/books', optionalAuth, async (ctx: Context) => {
  try {
    const userId = ctx.state.user?.userId;
    const userIdNum = userId ? parseInt(userId as string) : undefined;
    
    // 获取公开书籍（有公开音频的书籍）
    const publicBooks = await bookStore.getPublicBooks();
    
    // 如果用户已登录，获取用户自己的书籍
    let userBooks: any[] = [];
    if (userIdNum) {
      userBooks = await bookStore.getAllByUser(userIdNum, false);
    }
    
    // 合并并去重（按 id）
    const bookMap = new Map<string, any>();
    publicBooks.forEach(b => bookMap.set(b.id, b));
    userBooks.forEach(b => {
      if (!bookMap.has(b.id)) {
        bookMap.set(b.id, b);
      }
    });
    
    const books = Array.from(bookMap.values());
    
    ctx.body = { code: 0, message: 'success', data: { books } };
  } catch (error) {
    console.error('查询失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '查询失败' };
  }
});

/**
 * GET /api/book-generator/langgraph/public-books
 * 获取公开书籍列表（首页专用）
 * 只返回有公开音频的书籍
 */
router.get('/public-books', async (ctx: Context) => {
  try {
    const publicBooks = await bookStore.getPublicBooks();
    ctx.body = { code: 0, message: 'success', data: { books: publicBooks } };
  } catch (error) {
    console.error('查询公开书籍失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '查询失败' };
  }
});

/**
 * GET /api/book-generator/langgraph/my-books
 * 获取当前用户自己的书籍列表（管理页专用）
 * 只返回当前用户创建的书籍
 */
router.get('/my-books', optionalAuth, async (ctx: Context) => {
  try {
    const userId = ctx.state.user?.userId;
    if (!userId) {
      ctx.status = 401;
      ctx.body = { code: 1, message: '请先登录' };
      return;
    }
    
    const userBooks = await bookStore.getAllByUser(parseInt(userId as string), false);
    ctx.body = { code: 0, message: 'success', data: { books: userBooks } };
  } catch (error) {
    console.error('查询用户书籍失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '查询失败' };
  }
});

/**
 * PUT /api/book-generator/langgraph/books/:id/publish
 * 切换书籍公开状态
 */
router.put('/books/:id/publish', optionalAuth, async (ctx: Context) => {
  try {
    const bookId = ctx.params.id;
    const newStatus = await bookStore.togglePublish(bookId);
    ctx.body = { 
      code: 0, 
      message: 'success', 
      data: { isPublished: newStatus } 
    };
  } catch (error) {
    console.error('切换发布状态失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '操作失败' };
  }
});

/**
 * GET /api/book-generator/langgraph/books/:id
 * 获取书籍详情
 * 支持公开过滤：?filterPublic=true&userId=1
 */
router.get('/books/:id', optionalAuth, async (ctx: Context) => {
  try {
    const bookId = ctx.params.id as string;
    const userId = ctx.state.user?.userId || TEST_USER_ID;
    const filterPublic = ctx.query.filterPublic === 'true';
    
    const book = await bookStore.getById(bookId, filterPublic, parseInt(userId as string));

    if (!book) {
      ctx.status = 404;
      ctx.body = { code: 1, message: '书籍不存在' };
      return;
    }

    ctx.body = { code: 0, message: 'success', data: { book } };
  } catch (error) {
    console.error('查询失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '查询失败' };
  }
});

/**
 * GET /api/book-generator/langgraph/books/:id/progress
 * 获取书籍生成进度
 */
router.get('/books/:id/progress', async (ctx: Context) => {
  try {
    const bookId = ctx.params.id as string;
    const book = await bookStore.getById(bookId);

    if (!book) {
      ctx.status = 404;
      ctx.body = { code: 1, message: '书籍不存在' };
      return;
    }

    // 计算实际进度（基于章节完成情况）
    const completedChapters = book.chapters.filter((c) => c.status === 'completed').length;
    const totalChapters = book.outline?.chapters?.length || book.totalChapters || 0;

    // 如果有大纲，使用大纲章节数计算进度
    let progress = book.progress;
    if (totalChapters > 0 && book.status !== 'completed') {
      progress = Math.round((completedChapters / totalChapters) * 100);
    }

    ctx.body = {
      code: 0,
      message: 'success',
      data: {
        bookId,
        status: book.status,
        progress,
        completedChapters,
        totalChapters,
      },
    };
  } catch (error) {
    console.error('查询进度失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '查询失败' };
  }
});

/**
 * DELETE /api/book-generator/langgraph/books/:id
 * 删除书籍
 */
router.delete('/books/:id', async (ctx: Context) => {
  try {
    const bookId = ctx.params.id as string;
    await bookStore.delete(bookId);
    ctx.body = { code: 0, message: '删除成功' };
  } catch (error) {
    console.error('删除失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '删除失败' };
  }
});

/**
 * POST /api/book-generator/langgraph/books/:id/generate
 * 对已有书籍使用 LangGraph 生成
 */
router.post('/books/:id/generate', async (ctx: Context) => {
  try {
    const bookId = ctx.params.id as string;
    console.log(`[LangGraph Generate] 收到请求 bookId=${bookId}`);
    
    const body = (ctx.request.body || {}) as { bookScale?: string };
    const book = await bookStore.getById(bookId);
    console.log(`[LangGraph Generate] book对象:`, book ? '存在' : 'null');

    if (!book) {
      ctx.status = 404;
      ctx.body = { code: 1, message: '书籍不存在' };
      return;
    }

    // 防止重复生成：如果书籍正在生成中，拒绝请求
    if (book.status === 'generating') {
      console.log(`[LangGraph Generate] 书籍正在生成中，拒绝重复请求 bookId=${bookId}`);
      ctx.status = 400;
      ctx.body = { 
        code: 1, 
        message: '书籍正在生成中，请勿重复提交',
        data: {
          bookId,
          status: book.status,
          progress: book.progress,
        }
      };
      return;
    }

    // 优先使用请求传入的 scale，否则使用书籍保存的 scale，最后默认标准教程
    const bookScale = body.bookScale || book.bookScale || '标准教程';

    // 尝试将生成任务加入队列（队列只是为了改善用户体验）
    try {
      const jobId = await queueService.addBookGenerationTask({
        bookId,
        topic: book.description,
        bookScale,
      });
      
      console.log(`[LangGraph] 生成任务已加入队列: bookId=${bookId}, jobId=${jobId}`);
      
      ctx.body = {
        code: 0,
        message: 'LangGraph 生成任务已启动（队列模式）',
        data: {
          bookId,
          jobId,
          status: 'queued',
          mode: 'queue',
        },
      };
    } catch (queueError) {
      // 队列失败时，降级为同步执行（确保核心业务不受影响）
      console.warn(`[LangGraph] 队列不可用，降级为同步执行: bookId=${bookId}`, queueError);
      
      try {
        // 同步调用生成器，等待完成
        await langGraphGenerator.generate(bookId, book.description, bookScale);
        
        console.log(`[LangGraph] 同步执行完成: bookId=${bookId}`);
        
        ctx.body = {
          code: 0,
          message: 'LangGraph 生成任务已完成（同步模式）',
          data: {
            bookId,
            status: 'completed',
            mode: 'sync',
          },
        };
      } catch (generateError) {
        // 生成失败，更新书籍状态
        console.error(`[LangGraph] 同步执行失败: bookId=${bookId}`, generateError);
        await bookStore.update(bookId, {
          status: 'failed',
          errorMsg: generateError instanceof Error ? generateError.message : '生成失败',
        });
        
        ctx.body = {
          code: 0,
          message: 'LangGraph 生成任务失败',
          data: {
            bookId,
            status: 'failed',
            mode: 'sync',
            error: generateError instanceof Error ? generateError.message : '生成失败',
          },
        };
      }
    }
  } catch (error) {
    console.error('启动失败:', error);
    ctx.status = 500;
    ctx.body = {
      code: 1,
      message: error instanceof Error ? error.message : '启动失败',
    };
  }
});

/**
 * POST /api/book-generator/langgraph/books/:id/audio
 * 批量生成书籍所有小节的音频
 */
router.post('/books/:id/audio', async (ctx: Context) => {
  try {
    const bookId = ctx.params.id as string;
    const { voiceId = 'cherry' } = ctx.request.body as { voiceId?: string };

    const book = await bookStore.getById(bookId);
    if (!book) {
      ctx.status = 404;
      ctx.body = { code: 1, message: '书籍不存在' };
      return;
    }

    // 获取所有小节 (level=3)
    const chapters = await bookStore.getChapterTree(bookId);
    const subsections = chapters.filter((c: any) => c.level === 3);

    // 检查内容状态
    const subsectionsWithContent = subsections.filter((c: any) => c.content && c.contentStatus === 'completed');

    if (subsections.length === 0) {
      ctx.body = { code: 1, message: '没有小节' };
      return;
    }

    if (subsectionsWithContent.length === 0) {
      ctx.body = { 
        code: 1, 
        message: '没有内容生成完成的小节，请先生成内容',
        data: {
          totalSubsections: subsections.length,
          completedSubsections: 0,
        }
      };
      return;
    }

    if (subsections.length !== subsectionsWithContent.length) {
      console.log(`[Audio] 书籍 ${bookId} 共有 ${subsections.length} 个小节，其中 ${subsectionsWithContent.length} 个内容已生成完成`);
    }

    // 异步生成所有小节音频
    for (const sub of subsectionsWithContent) {
      bookStore.generateChapterAudioById(sub.id, book.userId || 1).catch(err => {
        console.error(`[Audio] 小节${sub.number}音频生成失败:`, err);
      });
    }

    ctx.body = {
      code: 0,
      message: '音频生成任务已启动',
      data: {
        totalSubsections: subsectionsWithContent.length,
        taskId: `audio_${bookId}_${Date.now()}`,
      },
    };
  } catch (error) {
    console.error('音频生成失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '音频生成失败' };
  }
});

/**
 * GET /api/book-generator/langgraph/books/:id/failed-chapters
 * 获取生成失败的小节列表
 */
router.get('/books/:id/failed-chapters', async (ctx: Context) => {
  try {
    const bookId = ctx.params.id as string;
    const book = await bookStore.getById(bookId);
    if (!book) {
      ctx.status = 404;
      ctx.body = { code: 1, message: '书籍不存在' };
      return;
    }

    // 获取所有失败的小节
    const chapters = await bookStore.getChapterTree(bookId);
    const failedSubsections = chapters.filter(c => c.status === 'failed');

    ctx.body = {
      code: 0,
      message: 'success',
      data: {
        bookId,
        failedCount: failedSubsections.length,
        failedChapters: failedSubsections.map(c => ({
          id: c.id,
          number: c.number,
          title: c.title,
          level: c.level,
          errorMsg: c.errorMsg,
          parentId: c.parentId,
        })),
      },
    };
  } catch (error) {
    console.error('获取失败小节失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '获取失败' };
  }
});

/**
 * POST /api/book-generator/langgraph/books/:id/resume
 * 从断点处继续生成（重试失败的小节）
 */
router.post('/books/:id/resume', async (ctx: Context) => {
  try {
    const bookId = ctx.params.id as string;
    const book = await bookStore.getById(bookId);
    if (!book) {
      ctx.status = 404;
      ctx.body = { code: 1, message: '书籍不存在' };
      return;
    }

    if (book.status === 'completed') {
      ctx.body = { code: 1, message: '书籍已生成完成，无需继续' };
      return;
    }

    // 获取失败的小节
    const chapters = await bookStore.getChapterTree(bookId);
    const failedSubsections = chapters.filter(c => c.status === 'failed');

    if (failedSubsections.length === 0) {
      ctx.body = { code: 1, message: '没有失败的小节需要重试' };
      return;
    }

    // 重置失败小节的状态为 pending
    for (const sub of failedSubsections) {
      await bookStore.updateChapterById(sub.id, {
        status: 'pending',
        errorMsg: null,
        content: null,
      });
    }

    // 将续生成任务加入队列
    const jobId = await queueService.addBookGenerationTask({
      bookId,
      topic: book.description || book.title,
      bookScale: book.bookScale || '标准教程',
    });
    
    console.log(`[LangGraph] 续生成任务已加入队列: bookId=${bookId}, jobId=${jobId}`);

    ctx.body = {
      code: 0,
      message: `已重启生成，将重试 ${failedSubsections.length} 个失败的小节`,
      data: {
        bookId,
        retryCount: failedSubsections.length,
        status: 'resuming',
      },
    };
  } catch (error) {
    console.error('继续生成失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '继续生成失败' };
  }
});

/**
 * POST /api/book-generator/langgraph/books/:id/retry-chapter
 * 单独重试某个失败的小节
 */
router.post('/books/:id/retry-chapter', async (ctx: Context) => {
  try {
    const bookId = ctx.params.id as string;
    const { chapterId } = ctx.request.body as { chapterId: number };

    if (!chapterId) {
      ctx.status = 400;
      ctx.body = { code: 1, message: '请提供章节 ID' };
      return;
    }

    // 获取所有章节查找指定的章节
    const chapters = await bookStore.getChapterTree(bookId);
    const chapter = chapters.find(c => c.id === chapterId);
    if (!chapter) {
      ctx.status = 404;
      ctx.body = { code: 1, message: '章节不存在' };
      return;
    }

    // 重置章节状态
    await bookStore.updateChapterById(chapterId, {
      status: 'pending',
      errorMsg: null,
      content: null,
    });

    ctx.body = {
      code: 0,
      message: '章节已重置为待生成状态',
      data: { chapterId },
    };
  } catch (error) {
    console.error('重试章节失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '重试失败' };
  }
});

/**
 * POST /api/book-generator/langgraph/books/:id/videos
 * 批量生成书籍所有章节视频
 */
router.post('/books/:id/videos', async (ctx: Context) => {
  try {
    const bookId = ctx.params.id as string;
    const book = await bookStore.getById(bookId);
    
    if (!book) {
      ctx.status = 404;
      ctx.body = { code: 1, message: '书籍不存在' };
      return;
    }

    // 获取所有小节 (level=3)
    const chapters = await bookStore.getChapterTree(bookId);
    const subsections = chapters.filter((c: any) => c.level === 3);

    // 过滤出有音频的小节（audioUrl存在且不为空）
    const subsectionsWithAudio = subsections.filter((c: any) => c.audioUrl && c.audioUrl !== '');

    if (subsections.length === 0) {
      ctx.body = { code: 1, message: '没有小节' };
      return;
    }

    if (subsectionsWithAudio.length === 0) {
      ctx.body = { 
        code: 1, 
        message: '没有音频生成完成的小节，请先生成音频',
        data: {
          totalSubsections: subsections.length,
          audioCompletedSubsections: 0,
        }
      };
      return;
    }

    if (subsections.length !== subsectionsWithAudio.length) {
      console.log(`[Video] 书籍 ${bookId} 共有 ${subsections.length} 个小节，其中 ${subsectionsWithAudio.length} 个音频已生成完成`);
    }

    // 异步生成所有章节视频
    const taskId = `video_${bookId}_${Date.now()}`;
    console.log(`[Video] 开始批量生成视频: bookId=${bookId}, taskId=${taskId}, 总数=${subsectionsWithAudio.length}`);

    for (const sub of subsectionsWithAudio) {
      // 异步处理每个章节的视频生成
      (async () => {
        try {
          console.log(`[Video] 开始生成章节 ${sub.number} 的视频: ${sub.title}`);
          
          // 从书籍章节创建视频项目
          const project = await createVideoProjectFromBook(
            parseInt(bookId),
            sub.id,
            book.userId || 1
          );

          if (!project) {
            console.error(`[Video] 章节 ${sub.number} 视频项目创建失败`);
            return;
          }

          console.log(`[Video] 章节 ${sub.number} 视频项目创建成功: projectId=${project.id}`);

          // 生成视频
          const result = await generateVideoForProject(project.id);

          if (result.success && result.outputUrl) {
            // 更新章节的视频URL
            await bookStore.updateChapterById(sub.id, {
              videoUrl: result.outputUrl,
              videoDuration: result.duration,
            });
            console.log(`[Video] 章节 ${sub.number} 视频生成成功: ${result.outputUrl}`);
          } else {
            console.error(`[Video] 章节 ${sub.number} 视频生成失败:`, result.error);
          }
        } catch (error) {
          console.error(`[Video] 章节 ${sub.number} 视频生成异常:`, error);
        }
      })();
    }

    ctx.body = {
      code: 0,
      message: '视频生成任务已启动',
      data: {
        taskId,
        totalChapters: subsectionsWithAudio.length,
        totalSubsections: subsections.length,
      },
    };
  } catch (error) {
    console.error('批量生成视频失败:', error);
    ctx.status = 500;
    ctx.body = { code: 1, message: error instanceof Error ? error.message : '批量生成视频失败' };
  }
});

export default router;