/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

import { MigrationWizardConstants } from "chrome://browser/content/migration/migration-wizard-constants.mjs";

/**
 * This class is responsible for updating the state of a <migration-wizard>
 * component, and for listening for events from that component to perform
 * various migration functions.
 */
export class MigrationWizardChild extends JSWindowActorChild {
  #wizardEl = null;

  /**
   * General event handler function for events dispatched from the
   * <migration-wizard> component.
   *
   * @param {Event} event
   *   The DOM event being handled.
   * @returns {Promise}
   */
  async handleEvent(event) {
    if (event.type == "MigrationWizard:Init") {
      this.#wizardEl = event.target;
      let migrators = await this.sendQuery("GetAvailableMigrators");
      this.setComponentState({
        migrators,
        page: MigrationWizardConstants.PAGES.SELECTION,
      });
    }
  }

  /**
   * Calls the `setState` method on the <migration-wizard> component. The
   * state is cloned into the execution scope of this.#wizardEl.
   *
   * @param {object} state The state object that a <migration-wizard>
   *   component expects. See the documentation for the element's setState
   *   method for more details.
   */
  setComponentState(state) {
    if (!this.#wizardEl) {
      return;
    }
    // We waive XrayWrappers in the event that the element is embedded in
    // a document without system privileges, like about:welcome.
    Cu.waiveXrays(this.#wizardEl).setState(
      Cu.cloneInto(
        state,
        // ownerGlobal doesn't exist in content windows.
        // eslint-disable-next-line mozilla/use-ownerGlobal
        this.#wizardEl.ownerDocument.defaultView
      )
    );
  }
}