import {AbsURLScheme} from 'scriptable-abstract';

interface URLSchemeState {
  schemes: Set<string>;
  lastOpenedURL: string | null;
}

const DEFAULT_STATE: URLSchemeState = {
  schemes: new Set(),
  lastOpenedURL: null,
};

/**
 * Mock implementation of Scriptable's URLScheme global variable
 * @implements URLScheme
 */
export class MockURLScheme extends AbsURLScheme<URLSchemeState> {
  static get instance(): MockURLScheme {
    return super.instance as MockURLScheme;
  }

  constructor() {
    super(DEFAULT_STATE);
  }

  /**
   * @inheritdoc
   */
  async open(urlScheme: string): Promise<void> {
    this.setState({lastOpenedURL: urlScheme});
  }

  /**
   * @inheritdoc
   */
  async fromURLString(urlString: string): Promise<string> {
    return urlString;
  }

  /**
   * @inheritdoc
   */
  async forActionExtension(): Promise<string> {
    return this.state.lastOpenedURL ?? '';
  }

  /**
   * @inheritdoc
   */
  async forNotification(): Promise<string> {
    return this.state.lastOpenedURL ?? '';
  }

  /**
   * @additional
   * Register a URL scheme for testing
   */
  registerScheme(scheme: string): void {
    this.setState(state => ({
      schemes: new Set([...state.schemes, scheme]),
    }));
  }

  /**
   * @additional
   * Check if a URL scheme is registered
   */
  isRegistered(scheme: string): boolean {
    return this.state.schemes.has(scheme);
  }

  /**
   * @additional
   * Get the last opened URL
   */
  getLastOpenedURL(): string | null {
    return this.state.lastOpenedURL;
  }

  /**
   * @additional
   * Clear all registered schemes and last opened URL
   */
  clear(): void {
    this.setState({
      schemes: new Set(),
      lastOpenedURL: null,
    });
  }
}