/**
 * 文件上传API路由
 * Handle file uploads for videos and cover images
 */
import { Router, type Request, type Response } from 'express';
import multer from 'multer';
import path from 'path';
import fs from 'fs';
import { authenticateToken } from '../middleware/auth.js';

const router = Router();

// Multer错误处理中间件
const handleMulterError = (error: any, req: Request, res: Response, next: any) => {
  console.error('Multer错误:', error);
  
  if (error instanceof multer.MulterError) {
    switch (error.code) {
      case 'LIMIT_FILE_SIZE':
        return res.status(400).json({
          success: false,
          message: '文件大小超出限制（最大100MB）'
        });
      case 'LIMIT_FILE_COUNT':
        return res.status(400).json({
          success: false,
          message: '文件数量超出限制'
        });
      case 'LIMIT_UNEXPECTED_FILE':
        return res.status(400).json({
          success: false,
          message: '意外的文件字段'
        });
      default:
        return res.status(400).json({
          success: false,
          message: `文件上传错误: ${error.message}`
        });
    }
  }
  
  if (error.message) {
    return res.status(400).json({
      success: false,
      message: error.message
    });
  }
  
  return res.status(500).json({
    success: false,
    message: '文件上传失败'
  });
};

// 确保上传目录存在
const ensureUploadDir = (dir: string) => {
  if (!fs.existsSync(dir)) {
    fs.mkdirSync(dir, { recursive: true });
  }
};

// 配置multer用于视频文件上传
const videoStorage = multer.memoryStorage();
const videoUpload = multer({ 
  storage: videoStorage,
  limits: {
    fileSize: 100 * 1024 * 1024 // 100MB限制
  },
  fileFilter: (req, file, cb) => {
    console.log('视频文件过滤器检查，文件类型:', file.mimetype, '文件名:', file.originalname);
    
    // 获取文件扩展名
    const fileExtension = path.extname(file.originalname).toLowerCase();
    const mimeType = file.mimetype ? file.mimetype.toLowerCase() : '';
    
    // 支持的MIME类型（与前端保持一致）
    const allowedTypes = [
      // 标准视频MIME类型
      'video/mp4', 'video/mpeg', 'video/quicktime', 'video/x-msvideo',
      'video/x-ms-wmv', 'video/x-flv', 'video/webm', 'video/ogg',
      'video/3gpp', 'video/3gpp2', 'video/x-matroska', 'video/mp2t',
      'video/x-ms-asf', 'video/x-m4v', 'video/divx', 'video/xvid',
      // 应用程序类型（某些视频格式）
      'application/octet-stream', 'application/x-msvideo',
      'application/vnd.rn-realmedia', 'application/x-shockwave-flash'
    ];
    
    // 支持的文件扩展名
    const allowedExtensions = [
      '.mp4', '.webm', '.ogg', '.avi', '.mov', '.3gp', '.3g2', 
      '.wmv', '.flv', '.mkv', '.m4v', '.ts', '.asf', '.mpg', 
      '.mpeg', '.m2v', '.rmvb', '.rm', '.divx', '.xvid', 
      '.f4v', '.m2ts', '.mts', '.vob', '.dat', '.amv'
    ];
    
    // 验证逻辑：
    // 1. 扩展名匹配（优先级最高）
    // 2. MIME类型完全匹配
    // 3. MIME类型以video/开头且扩展名正确
    // 4. MIME类型为空但扩展名正确
    const isExtensionValid = allowedExtensions.includes(fileExtension);
    const isMimeTypeValid = allowedTypes.includes(mimeType);
    const isVideoMimeType = mimeType.startsWith('video/');
    
    const isValid = isExtensionValid || isMimeTypeValid || (isVideoMimeType && isExtensionValid) || (!mimeType && isExtensionValid);
    
    console.log('文件验证结果:', {
      fileExtension,
      mimeType,
      isExtensionValid,
      isMimeTypeValid,
      isVideoMimeType,
      isValid
    });
    
    if (isValid) {
      console.log('视频文件类型检查通过');
      cb(null, true);
    } else {
      console.log('视频文件类型检查失败，不支持的格式:', mimeType, '扩展名:', fileExtension);
      cb(new Error(`不支持的视频格式。文件类型: ${mimeType}, 扩展名: ${fileExtension}`));
    }
  }
});

// 配置multer用于封面图片上传
const coverStorage = multer.memoryStorage();
const coverUpload = multer({ 
  storage: coverStorage,
  limits: {
    fileSize: 10 * 1024 * 1024 // 10MB限制
  },
  fileFilter: (req, file, cb) => {
    console.log('封面图片过滤器检查，文件类型:', file.mimetype);
    const allowedTypes = ['image/jpeg', 'image/jpg', 'image/png', 'image/gif', 'image/webp'];
    if (allowedTypes.includes(file.mimetype)) {
      console.log('封面图片类型检查通过');
      cb(null, true);
    } else {
      console.log('封面图片类型检查失败，不支持的格式:', file.mimetype);
      cb(new Error('不支持的图片格式'));
    }
  }
});

/**
 * 上传视频文件
 * POST /api/upload/video
 */
router.post('/video', authenticateToken, videoUpload.single('video'), handleMulterError, async (req: Request, res: Response): Promise<void> => {
  try {
    console.log('视频文件上传请求开始');
    const file = req.file;
    
    if (!file) {
      console.log('错误: 没有视频文件');
      res.status(400).json({
        success: false,
        message: '请选择要上传的视频文件'
      });
      return;
    }

    // 生成文件名
    const timestamp = Date.now();
    const originalName = file.originalname;
    const ext = path.extname(originalName);
    const filename = `video_${timestamp}_${Math.random().toString(36).substring(2)}${ext}`;
    
    // 确保上传目录存在
    const uploadDir = path.join(process.cwd(), 'uploads', 'videos');
    ensureUploadDir(uploadDir);
    
    // 保存文件
    const filePath = path.join(uploadDir, filename);
    const relativePath = path.join('uploads', 'videos', filename).replace(/\\/g, '/');
    
    console.log('开始保存视频文件到:', filePath);
    fs.writeFileSync(filePath, file.buffer);
    console.log('视频文件保存成功');

    // 返回文件URL
    const fileUrl = `/${relativePath}`;
    
    res.status(200).json({
      success: true,
      message: '视频文件上传成功',
      data: {
        url: fileUrl,
        filename: filename,
        size: file.size,
        mimetype: file.mimetype
      }
    });
  } catch (error) {
    console.error('视频文件上传失败:', error);
    res.status(500).json({
      success: false,
      message: '视频文件上传失败'
    });
  }
});

/**
 * 上传封面图片
 * POST /api/upload/cover
 */
router.post('/cover', authenticateToken, coverUpload.single('cover'), handleMulterError, async (req: Request, res: Response): Promise<void> => {
  try {
    console.log('封面图片上传请求开始');
    const file = req.file;
    
    if (!file) {
      console.log('错误: 没有封面图片文件');
      res.status(400).json({
        success: false,
        message: '请选择要上传的封面图片'
      });
      return;
    }

    // 生成文件名
    const timestamp = Date.now();
    const originalName = file.originalname;
    const ext = path.extname(originalName);
    const filename = `cover_${timestamp}_${Math.random().toString(36).substring(2)}${ext}`;
    
    // 确保上传目录存在
    const uploadDir = path.join(process.cwd(), 'uploads', 'covers');
    ensureUploadDir(uploadDir);
    
    // 保存文件
    const filePath = path.join(uploadDir, filename);
    const relativePath = path.join('uploads', 'covers', filename).replace(/\\/g, '/');
    
    console.log('开始保存封面图片到:', filePath);
    fs.writeFileSync(filePath, file.buffer);
    console.log('封面图片保存成功');

    // 返回文件URL
    const fileUrl = `/${relativePath}`;
    
    res.status(200).json({
      success: true,
      message: '封面图片上传成功',
      data: {
        url: fileUrl,
        filename: filename,
        size: file.size,
        mimetype: file.mimetype
      }
    });
  } catch (error) {
    console.error('封面图片上传失败:', error);
    res.status(500).json({
      success: false,
      message: '封面图片上传失败'
    });
  }
});

export default router;