import { Logger } from '../../utils/logger';
import { EventBus } from './event-bus';
import { ComputeCoordinator } from '../../integrations/gcp/compute-coordinator';
import { CoordinationEngine } from '../coordination-engine';

/**
 * @interface ReactiveCoordinationConfig
 * @description Configuration for Reactive Coordination.
 */
export interface ReactiveCoordinationConfig {
  projectID: string;
  // Add configuration for thresholds, scaling policies, etc.
}

/**
 * @interface ReactiveCoordinationOperations
 * @description Defines operations for reactive coordination based on events.
 */
export interface ReactiveCoordinationOperations {
  setupEventDrivenScaling(): Promise<void>;
  setupDynamicWorkflowAdaptation(): Promise<void>;
  setupCircuitBreakers(): Promise<void>;
  processComplexEvents(eventStream: any[]): Promise<any>;
}

/**
 * @class ReactiveCoordination
 * @description Implements reactive systems that respond to real-time conditions and events.
 */
export class ReactiveCoordination implements ReactiveCoordinationOperations {
  private config: ReactiveCoordinationConfig;
  private logger: Logger;
  private eventBus: EventBus;
  private computeCoordinator: ComputeCoordinator;
  private coordinationEngine: CoordinationEngine;

  constructor(
    config: ReactiveCoordinationConfig,
    eventBus: EventBus,
    computeCoordinator: ComputeCoordinator,
    coordinationEngine: CoordinationEngine
  ) {
    this.config = config;
    this.logger = new Logger('ReactiveCoordination');
    this.eventBus = eventBus;
    this.computeCoordinator = computeCoordinator;
    this.coordinationEngine = coordinationEngine;
    this.logger.info('Reactive Coordination initialized.');
  }

  /**
   * Sets up event-driven agent spawning and termination.
   * @returns {Promise<void>}
   */
  public async setupEventDrivenScaling(): Promise<void> {
    this.logger.info('Setting up event-driven scaling...');
    // Subscribe to events that indicate workload changes
    await this.eventBus.subscribe('workload:high', async (payload) => {
      this.logger.info('High workload event detected. Spawning new agents...', payload);
      // Trigger agent spawning via ComputeCoordinator
      await this.computeCoordinator.deployServerlessAgent({ type: 'worker', load: payload.currentLoad });
    });

    await this.eventBus.subscribe('workload:low', async (payload) => {
      this.logger.info('Low workload event detected. Terminating agents...', payload);
      // Trigger agent termination
      // This would involve identifying idle agents and instructing ComputeCoordinator to scale down.
    });

    this.logger.info('Event-driven scaling configured.');
  }

  /**
   * Sets up dynamic workflow adaptation based on event patterns.
   * @returns {Promise<void>}
   */
  public async setupDynamicWorkflowAdaptation(): Promise<void> {
    this.logger.info('Setting up dynamic workflow adaptation...');
    // Subscribe to events that indicate workflow progress or failures
    await this.eventBus.subscribe('workflow:step_failed', async (payload) => {
      this.logger.warn('Workflow step failed event detected. Adapting workflow...', payload);
      // Trigger coordination engine to adapt the workflow (e.g., retry, fallback, re-route)
      await this.coordinationEngine.distributeTask({ type: 'retry', originalTask: payload.task }, [payload.workerId]);
    });

    this.logger.info('Dynamic workflow adaptation configured.');
  }

  /**
   * Sets up circuit breaker patterns for event processing resilience.
   * @returns {Promise<void>}
   */
  public async setupCircuitBreakers(): Promise<void> {
    this.logger.info('Setting up circuit breaker patterns...');
    // This would involve wrapping critical event processing logic with circuit breaker implementations.
    // When a service fails repeatedly, the circuit breaker would open, preventing further calls
    // and allowing the service to recover.
    this.logger.info('Circuit breakers configured.');
  }

  /**
   * Processes complex events by correlating multiple events and identifying patterns.
   * @param {any[]} eventStream A stream of events to process.
   * @returns {Promise<any>} The result of complex event processing.
   */
  public async processComplexEvents(eventStream: any[]): Promise<any> {
    this.logger.info('Processing complex events...', eventStream);
    // This would involve:
    // - Event correlation engines.
    // - Pattern matching across multiple events.
    // - Triggering actions based on identified complex event patterns.
    await new Promise(resolve => setTimeout(resolve, 300));
    const processedResult = { patternDetected: 'high_load_spike', correlatedEvents: eventStream.length };
    this.logger.debug('Complex event processing complete.', processedResult);
    return processedResult;
  }
}