import { useCallback, useEffect, useState } from 'react'

export type AuthUser = {
  user?: string
  email?: string
  name?: string
  preferred_username?: string
  auth_enabled?: boolean
}

type AuthState =
  | { status: 'loading'; user: null }
  | { status: 'anon'; user: null }
  | { status: 'authed'; user: AuthUser }

export function useAuth(): AuthState & { refresh: () => Promise<void> } {
  const [state, setState] = useState<AuthState>({ status: 'loading', user: null })

  const refresh = useCallback(async () => {
    try {
      const r = await fetch('/api/auth/me', { credentials: 'same-origin' })
      if (r.status === 401) {
        setState({ status: 'anon', user: null })
        return
      }
      if (!r.ok) {
        setState({ status: 'anon', user: null })
        return
      }
      const me = (await r.json()) as AuthUser
      setState({ status: 'authed', user: me })
    } catch {
      setState({ status: 'anon', user: null })
    }
  }, [])

  useEffect(() => {
    void refresh()
  }, [refresh])

  return { ...state, refresh }
}