import { reactive, computed } from 'vue'
import { authApi } from '@/api'
import { setToken, getToken, tryRefresh } from '@/api/client'
import type { LoginResult, User } from '@/types'

const state = reactive<{
  user: User | null
  ready: boolean
  loading: boolean
}>({
  user: null,
  ready: false,
  loading: false,
})

async function restore(): Promise<void> {
  if (state.user) return
  if (!getToken()) {
    // No access token in storage: try the refresh cookie to recover a session.
    const fresh = await tryRefresh()
    if (!fresh) {
      state.ready = true
      return
    }
    setToken(fresh)
  }
  try {
    state.user = await authApi.me()
  } catch {
    state.user = null
  } finally {
    state.ready = true
  }
}

async function apply(result: LoginResult): Promise<void> {
  setToken(result.token.accessToken)
  state.user = result.user
}

async function login(account: string, password: string): Promise<void> {
  state.loading = true
  try {
    await apply(await authApi.login(account, password))
  } finally {
    state.loading = false
  }
}

async function register(data: { username: string; email: string; password: string; inviteCode?: string }): Promise<void> {
  state.loading = true
  try {
    await apply(await authApi.register(data))
  } finally {
    state.loading = false
  }
}

async function logout(): Promise<void> {
  try {
    await authApi.logout()
  } catch {
    // ignore network errors on logout
  }
  setToken('')
  state.user = null
}

async function refreshProfile(): Promise<void> {
  if (!getToken()) return
  state.user = await authApi.me()
}

export function useAuth() {
  return {
    state,
    user: computed(() => state.user),
    isAdmin: computed(() => state.user?.role === 'admin'),
    isAuthed: computed(() => !!state.user),
    restore,
    login,
    register,
    logout,
    refreshProfile,
  }
}