import Taro from '@tarojs/taro'
import { wxMiniappLogin, type WxMiniappLoginResponse } from '@/api/auth'
import { storage } from '@/utils/storage'
import { WX_OPENID_STORAGE_KEY, FALLBACK_WX_APP_ID } from '@/constants/auth'

// 取小程序 appId：正常环境走 accountInfo，异常（部分基座不支持）回退常量
function resolveAppId(): string {
  try {
    return Taro.getAccountInfoSync().miniProgram.appId || FALLBACK_WX_APP_ID
  } catch {
    return FALLBACK_WX_APP_ID
  }
}

// 登录步骤子状态（http 层把 200 内 Message 附加到返回值 message 字段）
export type LoginSubState = 'needUserInfo' | 'noMobile' | 'complete'

export function getLoginSubState(res: WxMiniappLoginResponse): LoginSubState {
  if (res.message === 'needUserInfo') return 'needUserInfo'
  if (res.message === 'noMobile') return 'noMobile'
  return 'complete'
}

// 微信一键登录主流程：
// Taro.login 换一次性 code → 组装 appId/openId → 调 miniapp/login → 缓存响应中的 openId
// 首次登录后端可能分步返回 needUserInfo / noMobile（仅绑定凭证，无 token），逐步授权后重调补全
export async function performWxLogin(): Promise<WxMiniappLoginResponse> {
  // Taro.login reject 时返回 { errMsg } 形状对象而非 Error，此处归一化为带 message 的 Error
  let code: string
  try {
    const r = await Taro.login()
    code = r.code
  } catch (e) {
    throw new Error(e instanceof Error ? e.message : '微信登录失败')
  }
  if (!code) throw new Error('获取微信登录凭证失败')
  const openId = storage.get<string>(WX_OPENID_STORAGE_KEY) ?? undefined
  console.log('[login] performWxLogin 请求', { appId: resolveAppId(), code, openId })
  const result = await wxMiniappLogin({ appId: resolveAppId(), code, openId })
  if (result.openId) storage.set(WX_OPENID_STORAGE_KEY, result.openId)
  console.log('[login] performWxLogin 结果', getLoginSubState(result), result)
  return result
}

// 重调登录接口的公共尾部：换新 code（一次性）→ 组装参数 → 调用 → 缓存 openId
async function reloginWith(
  openId: string,
  extra: { iv?: string; encryptedData?: string; phoneCode?: string }
): Promise<WxMiniappLoginResponse> {
  let code: string
  try {
    const r = await Taro.login()
    code = r.code
  } catch {
    throw new Error('获取微信登录凭证失败，请重试')
  }
  const params = { appId: resolveAppId(), code, openId, ...extra }
  console.log('[login] 重调登录接口', params)
  const result = await wxMiniappLogin(params)
  if (result.openId) storage.set(WX_OPENID_STORAGE_KEY, result.openId)
  console.log('[login] 重调结果', getLoginSubState(result), result)
  return result
}

// needUserInfo 二次授权：getUserProfile 拿 iv/encryptedData → 重调登录接口补用户资料
export async function completeUserInfoLogin(openId: string): Promise<WxMiniappLoginResponse> {
  let profile: { iv: string; encryptedData: string }
  try {
    const r = await Taro.getUserProfile({ desc: '用于完善会员资料' })
    profile = { iv: r.iv, encryptedData: r.encryptedData }
  } catch (e) {
    throw new Error(e instanceof Error ? e.message : (e as { errMsg?: string })?.errMsg || '授权失败')
  }
  return reloginWith(openId, profile)
}

// noMobile 三次授权：手机号授权按钮回调（open-type=getPhoneNumber）→ 重调登录接口
// detail 两种形态：新版含 code（动态令牌，后端可直连微信换取手机号）；
// 旧版含 iv/encryptedData（需与 session_key 解密，依赖同一 code 会话）
export async function completeMobileLogin(
  openId: string,
  detail: { iv: string; encryptedData: string; code?: string; errMsg?: string }
): Promise<WxMiniappLoginResponse> {
  if (!detail.iv && !detail.code) {
    throw new Error(detail.errMsg || '手机号授权失败')
  }
  return reloginWith(openId, {
    iv: detail.iv,
    encryptedData: detail.encryptedData,
    phoneCode: detail.code
  })
}