export class CsrfService {
  private static instance: CsrfService;
  private csrfToken: string | null = null;

  private constructor() {}

  public static getInstance(): CsrfService {
    if (!CsrfService.instance) {
      CsrfService.instance = new CsrfService();
    }
    return CsrfService.instance;
  }

  public async refreshCsrfToken(): Promise<void> {
    // Placeholder: fetch from backend if needed
    // this.csrfToken = ...
  }

  public getCsrfHeaders(): Record<string, string> {
    if (!this.csrfToken) {
      return {};
    }
    return {
      'X-CSRF-Token': this.csrfToken,
    };
  }

  public clearCsrfToken(): void {
    this.csrfToken = null;
  }
}

export const csrfService = CsrfService.getInstance();