// 后端 API 基础地址 - 根据环境自动切换
// 开发环境使用本地服务器，生产环境使用线上地址
const ENV_BASE_URL: Record<string, string> = {
  development: 'http://localhost:3000',
  production: 'https://api.example.com', // 部署时替换为真实域名
}

const BASE_URL = ENV_BASE_URL[process.env.NODE_ENV || 'development'] || 'http://localhost:3000'

export { BASE_URL }

interface RequestOptions {
  url: string
  method?: 'GET' | 'POST' | 'PUT' | 'DELETE'
  data?: Record<string, unknown>
  header?: Record<string, string>
}

interface ApiResponse<T = unknown> {
  code: number
  data: T
  message: string
}

/** 将下划线命名转换为驼峰命名 */
function toCamelCase(obj: any): any {
  if (obj === null || typeof obj !== 'object') return obj
  
  if (Array.isArray(obj)) {
    return obj.map(item => toCamelCase(item))
  }
  
  const result: any = {}
  for (const key in obj) {
    if (Object.prototype.hasOwnProperty.call(obj, key)) {
      const camelKey = key.replace(/_([a-z])/g, (_, letter) => letter.toUpperCase())
      result[camelKey] = toCamelCase(obj[key])
    }
  }
  return result
}

function getToken(): string {
  return uni.getStorageSync('token') || ''
}

export function request<T = unknown>(options: RequestOptions): Promise<T> {
  const { url, method = 'GET', data, header = {} } = options
  const token = getToken()

  return new Promise((resolve, reject) => {
    uni.request({
      url: `${BASE_URL}${url}`,
      method,
      data,
      header: {
        'Content-Type': 'application/json',
        ...(token ? { Authorization: `Bearer ${token}` } : {}),
        ...header,
      },
      success(res) {
        const statusCode = res.statusCode
        if (statusCode === 401) {
          uni.removeStorageSync('token')
          uni.showToast({ title: '请重新登录', icon: 'none' })
          autoLogin()
          reject(new Error('未授权'))
          return
        }
        if (statusCode >= 200 && statusCode < 300) {
          const body = res.data as ApiResponse<T>
          if (body.code === 0) {
            // 将下划线命名转换为驼峰命名
            const camelData = toCamelCase(body.data)
            resolve(camelData)
          } else {
            uni.showToast({ title: body.message || '请求失败', icon: 'none' })
            reject(new Error(body.message))
          }
        } else {
          uni.showToast({ title: '网络异常，请稍后重试', icon: 'none' })
          reject(new Error(`HTTP ${statusCode}`))
        }
      },
      fail(err) {
        uni.showToast({ title: '网络异常，请稍后重试', icon: 'none' })
        reject(err)
      },
    })
  })
}

/** 微信小程序自动登录 */
export function autoLogin(): Promise<void> {
  return new Promise((resolve, reject) => {
    uni.login({
      provider: 'weixin',
      success: async (loginRes) => {
        if (loginRes.code) {
          try {
            const data = await request<{ token: string; userId: number }>({
              url: '/api/auth/wx-login',
              method: 'POST',
              data: { code: loginRes.code },
            })
            uni.setStorageSync('token', data.token)
            resolve()
          } catch (err) {
            console.error('登录接口调用失败:', err)
            reject(err)
          }
        } else {
          console.error('微信登录获取 code 失败')
          reject(new Error('获取微信 code 失败'))
        }
      },
      fail: (err) => {
        console.error('uni.login 失败:', err)
        reject(err)
      },
    })
  })
}

export const get = <T = unknown>(url: string, data?: Record<string, unknown>) =>
  request<T>({ url, method: 'GET', data })

export const post = <T = unknown>(url: string, data?: Record<string, unknown>) =>
  request<T>({ url, method: 'POST', data })

export const put = <T = unknown>(url: string, data?: Record<string, unknown>) =>
  request<T>({ url, method: 'PUT', data })

export const del = <T = unknown>(url: string, data?: Record<string, unknown>) =>
  request<T>({ url, method: 'DELETE', data })