import type {
  ChangePasswordRequest,
  CurrentUserResponse, EmailRequest, NotificationListResponse,
  OkResponse,
  OtpRequestResponse, PasswordLoginRequest, RegisterCitizenRequest,
  RegisterCitizenResponse, RewardsResponse,
  TokenResponse, VerifyOtpRequest
} from "~/types/api";

export const useAuth = () => {
  const token = useCookie('auth_token', {
    maxAge: 60 * 60 * 12,
    sameSite: 'lax',
    watch: true
  })

  const tokenState = useState<string | null>('auth_token_state', () => token.value ?? null)

  type UserContext = CurrentUserResponse['user']
  const user = useState<UserContext | null>('auth_user', () => null)
  const isSyncingUser = useState<boolean>('auth_syncing', () => false)
  const isAuthenticated = computed(() => !!(tokenState.value || token.value))

  watch(() => token.value, (newVal) => {
    tokenState.value = newVal || null
  })

  const syncUser = async () => {
    const tokenVal = tokenState.value || token.value
    if (!tokenVal || isSyncingUser.value) return
    
    isSyncingUser.value = true
    try {
      const res = await fetchCurrentUser()
      if (res.ok) {
        console.log('[Auth] User synced successfully')
        user.value = res.user
      }
    } catch (error) {
      console.error('[Auth] Sync failed, logging out:', error)
      logout()
    } finally {
      isSyncingUser.value = false
    }
  }

  const handleLoginSuccess = async (jwtToken: string) => {
    token.value = jwtToken
    tokenState.value = jwtToken
    await syncUser()
  }

  const logout = () => {
    token.value = null
    tokenState.value = null
    user.value = null
    navigateTo('/auth/login')
  }

  const register = (body: RegisterCitizenRequest) =>
      useApiFetch<RegisterCitizenResponse>('/api/v1/auth/register', { method: 'POST', body })

  const requestOtp = (body: EmailRequest) =>
      useApiFetch<OtpRequestResponse>('/api/v1/auth/otp/request', { method: 'POST', body })

  const verifyOtp = (body: VerifyOtpRequest) =>
      useApiFetch<TokenResponse>('/api/v1/auth/otp/verify', { method: 'POST', body })

  const loginWithPassword = (body: PasswordLoginRequest) =>
      useApiFetch<TokenResponse>('/api/v1/auth/login/password', { method: 'POST', body })

  const changePassword = (body: ChangePasswordRequest) =>
      useApiFetch<OkResponse>('/api/v1/auth/change-password', { method: 'POST', body })

  const fetchCurrentUser = () =>
      useApiFetch<CurrentUserResponse>('/api/v1/me', { method: 'GET' })

  const fetchRewards = (query?: { page?: number; per_page?: number }) =>
      useApiFetch<RewardsResponse>('/api/v1/me/rewards', { method: 'GET', query })

  const fetchNotifications = (query?: { page?: number; per_page?: number }) =>
      useApiFetch<NotificationListResponse>('/api/v1/notifications', { method: 'GET', query })

  const markNotificationRead = (id: number) =>
      useApiFetch<OkResponse>(`/api/v1/notifications/${id}/read`, { method: 'PATCH' })

  return {
    user,
    token,
    tokenState,
    isSyncingUser,
    isAuthenticated,
    handleLoginSuccess,
    syncUser,
    logout,

    register,
    requestOtp,
    verifyOtp,
    loginWithPassword,
    changePassword,
    fetchCurrentUser,
    fetchRewards,
    fetchNotifications,
    markNotificationRead,
  }
}