import Ember from 'ember';

const {
  get,
  assert,
  isPresent,
  computed,
  Component
} = Ember;

const STATE_MSG = 'You must include a "state" attribute for every use of {{my-component}}';

const CHECKED = 'CHECKED';
const CHECKED_DISABLED = 'CHECKED_DISABLED';
const NOT_CHECKED = 'NOT_CHECKED';
const NOT_CHECKED_DISABLED = 'NOT_CHECKED_DISABLED';

const STATES = [CHECKED, CHECKED_DISABLED, NOT_CHECKED, NOT_CHECKED_DISABLED];
const VALID_STATES = new Set(STATES);

const isCheckbox = state => !(state === NOT_CHECKED_DISABLED);
const isChecked = state => [CHECKED, CHECKED_DISABLED].contains(state);
const isDisabled = state => [CHECKED_DISABLED, NOT_CHECKED_DISABLED].contains(state);

const stateToTitle = state => isCheckbox(state) ?
  isDisabled(state) ? '_t.payment.template-user.tooltip.role.canManage' : '_t.payment.template-user.tooltip.role.canAccess' :
  '_t.payment.template-user.tooltip.role.cannotAccess';

const stateToAriaLabel = state => isDisabled(state) ?
  '_t.payment.template-user.tooltip.role.cannotAccess' :
  '_t.payment.template-info.selectUserRole';

export default Component.extend({
  validateState: value => assert(STATE_MSG, (isPresent(value) && VALID_STATES.has(value))),

  didInitAttrs() {
    this._super(...arguments);
    let state = get(this, 'state');
    this.validateState(state);
  },

  state: computed({
    get() {
      return null;
    },
    set(key, state) {
      this.validateState(state, STATE_MSG);
      return state;
    }
  }),

  ariaLabel: computed('state', function() {
    let state = get(this, 'state');
    return stateToAriaLabel(state);
  }),

  label: computed('state', function() {
    let state = get(this, 'state');
    return stateToTitle(state);
  }),

  isCheckbox: computed('state', function() {
    let state = get(this, 'state');
    return isCheckbox(state);
  }),

  isChecked: computed('state', function() {
    let state = get(this, 'state');
    return isChecked(state);
  }),

  isDisabled: computed('state', function() {
    let state = get(this, 'state');
    return isDisabled(state);
  }),
});