import type { NextRequest } from 'next/server'
// 尝试加载根目录的可移植部署变量文件（不会覆盖已存在的真实环境变量）
try {
  // 动态引入，避免打包期间出错
  const { loadPortableEnvIfPresent } = require('./configLoader')
  if (typeof loadPortableEnvIfPresent === 'function') {
    loadPortableEnvIfPresent()
  }
} catch {}

export function resolveBaseUrl(req?: NextRequest): string {
  const appPublicUrl = process.env.APP_PUBLIC_URL
  const nextAuthUrl = process.env.NEXTAUTH_URL
  const isLocal = (url?: string | null) => !!url && /localhost|127\.0\.0\.1/i.test(url)

  if (appPublicUrl && !isLocal(appPublicUrl)) return appPublicUrl

  if (req) {
    const forwardedProto = req.headers.get('x-forwarded-proto')
    const forwardedHost = req.headers.get('x-forwarded-host')
    const originHeader = req.headers.get('origin')
    const host = req.headers.get('host')
    const headerBase =
      (forwardedHost && `${forwardedProto || 'http'}://${forwardedHost}`) ||
      (originHeader && !isLocal(originHeader) ? originHeader : null) ||
      (host ? `http://${host}` : null)
    if (headerBase) return headerBase
  }

  if (nextAuthUrl && !isLocal(nextAuthUrl)) return nextAuthUrl
  return 'http://localhost:3000'
}

export const defaultLogos = {
  // 后台默认使用内置静态资源；如需自定义，可通过环境变量覆盖
  // 当前仓库不再内置公共 Logo 资源；若未配置则走文字占位
  header: process.env.DEFAULT_HEADER_LOGO_URL || '',
  login: process.env.DEFAULT_LOGIN_LOGO_URL || '',
}

export const publicDefaults = {
  // 前端默认 Logo，与后端 defaultLogos 保持一致，方便通过 env 统一覆盖
  header: process.env.NEXT_PUBLIC_DEFAULT_HEADER_LOGO_URL || '',
  login: process.env.NEXT_PUBLIC_DEFAULT_LOGIN_LOGO_URL || '',
  intranetUrl: process.env.NEXT_PUBLIC_INTRANET_URL || '',
}

export function buildAbsoluteUrl(path: string, req?: NextRequest): string {
  const base = resolveBaseUrl(req)
  // 确保 base 不为空，避免返回 "http://"
  if (!base || base === 'http://' || base === 'https://') {
    return path.startsWith('http://') || path.startsWith('https://') 
      ? path 
      : `http://localhost:3000${path.startsWith('/') ? path : `/${path}`}`
  }
  if (!path) return base
  if (path.startsWith('http://') || path.startsWith('https://')) return path
  return `${base}${path.startsWith('/') ? path : `/${path}`}`
}

// Feature flags (can be overridden via SystemSettings in future)
export const featureFlags = {
  aiEditEnabled: (process.env.AI_EDIT_ENABLED || 'false').toLowerCase() === 'true',
  tunnelEnabled: (process.env.TUNNEL_ENABLED || 'false').toLowerCase() === 'true',
}