NavigationLoader.ts

import Resolvable from '@secret-agent/commons/Resolvable';
import { ILifecycleEvents, IPuppetNavigationLoader } from '@secret-agent/interfaces/IPuppetFrame';
import { IBoundLog } from '@secret-agent/interfaces/ILog';

export class NavigationLoader {
  public get isNavigationComplete() {
    return this.navigationResolver.isResolved;
  }

  public readonly lifecycle: ILifecycleEvents = {};
  public navigationResolver = new Resolvable<Error | string>();
  public url: string;

  private afterStoppedLoadingTimeout: NodeJS.Timeout;
  private logger: IBoundLog;

  constructor(readonly id: string, logger: IBoundLog) {
    this.logger = logger.createChild(module, {
      loaderId: this.id,
    });
  }

  public setNavigationResult(result?: Error | string) {
    this.navigationResolver.resolve(result ?? null);
    if (result && typeof result === 'string') {
      this.url = result;
    }
  }

  public clearStoppedLoading(): void {
    clearTimeout(this.afterStoppedLoadingTimeout);
  }

  public onStoppedLoading() {
    clearTimeout(this.afterStoppedLoadingTimeout);

    this.afterStoppedLoadingTimeout = setTimeout(this.markLoaded.bind(this), 50).unref();
  }

  public onLifecycleEvent(name: string) {
    if (
      (name === 'commit' || name === 'DOMContentLoaded' || name === 'load') &&
      !this.isNavigationComplete
    ) {
      this.logger.info('Resolving loader on lifecycle', { lifecycleEvent: name });
      this.clearStoppedLoading();
      this.setNavigationResult();
    }

    this.lifecycle[name] ??= new Date();
  }

  public markLoaded(): void {
    if (!this.lifecycle.load) {
      this.onLifecycleEvent('DOMContentLoaded');
      this.onLifecycleEvent('load');
    }
  }

  public toJSON(): IPuppetNavigationLoader {
    return {
      id: this.id,
      isNavigationComplete: this.isNavigationComplete,
      lifecycle: this.lifecycle,
      url: this.url,
    };
  }
}