/**
 * GUARDiA Messenger — 인증 토큰 유틸
 * SecureStore에 저장된 JWT 토큰을 읽어온다. (키: grd_token)
 */
import * as SecureStore from 'expo-secure-store'

const TOKEN_KEY = 'grd_token'
const USER_KEY = 'grd_user'

export async function getToken(): Promise<string | null> {
  try {
    return await SecureStore.getItemAsync(TOKEN_KEY)
  } catch {
    return null
  }
}

export async function getStoredUser<T = any>(): Promise<T | null> {
  try {
    const raw = await SecureStore.getItemAsync(USER_KEY)
    return raw ? (JSON.parse(raw) as T) : null
  } catch {
    return null
  }
}

/** 인증 헤더가 포함된 fetch 래퍼. */
export async function authFetch(input: string, init: RequestInit = {}): Promise<Response> {
  const token = await getToken()
  const headers: Record<string, string> = {
    'Content-Type': 'application/json',
    ...(init.headers as Record<string, string> | undefined),
  }
  if (token) headers.Authorization = `Bearer ${token}`
  return fetch(input, { ...init, headers })
}