import multer from 'multer';
import fs from 'node:fs';
import path from 'node:path';
import { callNodeListener } from 'h3';
import { R } from '#server/utils/response';

// 类型定义
interface IFile {
  name: string;
  url: string;   // 前端可直接访问的 URL
  path: string;  // 服务器存储路径
  mimeType: string;
  size: number;
}

export default defineWrappedResponseHandler(async (event) => {
  try {
    // 存储目录
    const uploadDir = path.join(process.cwd(), 'public/assets');

    // 自动创建目录
    if (!fs.existsSync(uploadDir)) {
      fs.mkdirSync(uploadDir, { recursive: true });
    }

    // 配置存储
    const storage = multer.diskStorage({
      destination: uploadDir,
      filename: (req, file, cb) => {
        // 生成唯一文件名：时间戳 + 原始文件名（安全处理）
        const uniqueSuffix = Date.now() + '-' + Math.round(Math.random() * 1e9);
        // 获取文件后缀
        const ext = path.extname(file.originalname).toLowerCase();
        // 干净的文件名（只保留字母数字）
        const baseName = path.basename(file.originalname, ext).replace(/[^a-z0-9]/gi, '-');
        // 最终文件名（带后缀）
        const filename = `${uniqueSuffix}-${baseName}${ext}`;
        cb(null, filename);
      },
    });

    // 上传配置
    const upload = multer({
      storage,
      limits: {
        fileSize: 5 * 1024 * 1024, // 5MB 限制
      },
      fileFilter: (req, file, cb) => {
        const allowedTypes = ['image/png', 'image/jpeg', 'image/jpg', 'image/webp'];
        if (allowedTypes.includes(file.mimetype)) {
          cb(null, true);
        } else {
          cb(new Error('只支持 PNG/JPG/WebP 格式图片'));
        }
      },
    });

    // 执行上传（最多 10 个文件）
    await callNodeListener(
      // @ts-expect-error Nuxt 类型兼容
      upload.array('file', 10),
      event.node.req,
      event.node.res
    );

    // 获取上传后的文件
    // @ts-expect-error
    const uploadedFiles = event.node.req.files || [];

    if (!Array.isArray(uploadedFiles) || uploadedFiles.length === 0) {
      throw createError({ statusCode: 400, statusMessage: '请选择要上传的图片' });
    }

    // 格式化返回数据（与 `public` 静态中间件路径一致：`/public/assets/...`）
    const result: IFile[] = uploadedFiles.map((file: { originalname: string; filename: string; path: string; mimetype: string; size: number }) => ({
      name: file.originalname,
      url: `/public/assets/${file.filename}`,
      path: file.path,
      mimeType: file.mimetype,
      size: file.size,
    }));

    return R.success({ files: result });
  } catch (err: unknown) {
    console.error('上传失败:', err);
    if (err && typeof err === 'object' && 'statusCode' in err) {
      throw err;
    }
    const msg = err instanceof Error ? err.message : '上传失败';
    throw createError({ statusCode: 400, statusMessage: msg });
  }
});