Class EventBus

src/web-ui/src/infrastructure/event-bus/EventBus.ts:34–303

}

export class EventBus {
  private listeners = new Map<string, Set<EventHandler>>();
  private onceListeners = new Map<string, Set<EventHandler>>();
  private options: Required<EventBusOptions>;
  private eventHistory: EventMetadata[] = [];
  private readonly MAX_HISTORY = 1000;

  constructor(options: EventBusOptions = {}) {
    this.options = {
      maxListeners: options.maxListeners ?? 100,
      enableLogging: options.enableLogging ?? false,
      timeout: options.timeout ?? 5000
    };
  }

  /**
   * Subscribe to an event.
   */
  on<T = any>(event: string, handler: EventHandler<T>): EventUnsubscriber {
    this.validateEventName(event);
    this.validateHandler(handler);

    if (!this.listeners.has(event)) {
      this.listeners.set(event, new Set());
    }

    const handlers = this.listeners.get(event)!;
    
    // Enforce max listeners per event.
    if (handlers.size >= this.options.maxListeners) {
      throw new Error(`Too many listeners for event '${event}'. Maximum is ${this.options.maxListeners}`);
    }

    handlers.add(handler);

    if (this.options.enableLogging) {
      log.debug('Added listener', { event, totalListeners: handlers.size });
    }

    // Return the unsubscribe function.
    return () => this.off(event, handler);
  }

  /**
   * Subscribe to an event once.
   */
  once<T = any>(event: string, handler: EventHandler<T>): EventUnsubscriber {
    this.validateEventName(event);
    this.validateHandler(handler);

    if (!this.onceListeners.has(event)) {
      this.onceListeners.set(event, new Set());
    }

    const handlers = this.onceListeners.get(event)!;
    handlers.add(handler);

    if (this.options.enableLogging) {