import { writeFileSync, existsSync, mkdirSync } from 'fs'
import { join, extname } from 'path'
import { requireAdmin } from '../../utils/auth.js'

// 允许的图片类型
const ALLOWED_TYPES = ['image/jpeg', 'image/png', 'image/webp', 'image/gif', 'image/svg+xml']
const MAX_SIZE = 10 * 1024 * 1024 // 10MB

export default defineEventHandler(async (event) => {
  requireAdmin(event)

  const formData = await readMultipartFormData(event)
  if (!formData || !formData.length) {
    throw createError({ statusCode: 422, message: '请选择要上传的文件' })
  }

  const results = []

  for (const file of formData) {
    if (!file.filename || !file.data) continue

    // 校验文件类型
    const mimeType = file.type || ''
    if (!ALLOWED_TYPES.includes(mimeType)) {
      throw createError({ statusCode: 422, message: `不支持的文件类型: ${mimeType}，仅支持 JPG/PNG/WebP/GIF/SVG` })
    }

    // 校验文件大小
    if (file.data.length > MAX_SIZE) {
      throw createError({ statusCode: 422, message: `文件过大，最大 10MB` })
    }

    // 生成文件名: 时间戳-原始文件名
    // 只保留 ASCII 字母数字下划线短横，中文/特殊字符一律去掉，避免 URL 编码与静态服务文件名不一致导致 404
    const ext = extname(file.filename).toLowerCase()
    const stripped = file.filename
      .replace(ext, '')
      .replace(/[^a-zA-Z0-9_-]/g, '')
      .slice(0, 30)
    const safeName = stripped || 'img'
    const fileName = `${Date.now()}-${safeName}${ext}`

    // 按年月分目录
    const now = new Date()
    const subDir = `${now.getFullYear()}${String(now.getMonth() + 1).padStart(2, '0')}`
    const uploadDir = join(process.cwd(), 'public', 'uploads', subDir)

    if (!existsSync(uploadDir)) {
      mkdirSync(uploadDir, { recursive: true })
    }

    const filePath = join(uploadDir, fileName)
    writeFileSync(filePath, file.data)

    const url = `/uploads/${subDir}/${fileName}`
    results.push({ url, name: file.filename, size: file.data.length })
  }

  return { success: true, files: results }
})