import { ref, readonly, computed } from 'vue';
 
export function useAuthMachine() {
  const state = ref('IDLE'); // IDLE | LOADING | AUTHENTICATED
 
  const transition = (target) => {
    const validTransitions = {
      IDLE: ['LOADING'],
      LOADING: ['AUTHENTICATED', 'IDLE'],
      AUTHENTICATED: ['IDLE']
    };
    if (validTransitions[state.value].includes(target)) {
      state.value = target;
    }
  };
 
  return {
    state: readonly(state),
    isAuthenticated: computed(() => state.value === 'AUTHENTICATED'),
    login: () => transition('LOADING'),
    logout: () => transition('IDLE')
  };
}