import { Logger } from '../../utils/logger';
import { PredictiveCoordinationSystem } from './predictive-system';

/**
 * @interface AdaptiveBalancingConfig
 * @description Configuration for the Adaptive Load Balancer.
 */
export interface AdaptiveBalancingConfig {
  projectID: string;
  // Add configuration for load balancing algorithms, thresholds, etc.
}

/**
 * @interface AdaptiveBalancingOperations
 * @description Defines operations for adaptive load balancing and scaling.
 */
export interface AdaptiveBalancingOperations {
  adjustWorkerAssignments(currentLoad: any, workerPool: any[]): Promise<any[]>;
  triggerDynamicScaling(predictedDemand: any): Promise<void>;
  distributeLoadGeographically(task: any, regions: string[]): Promise<string>;
  balanceLoadCostAware(task: any, workerPool: any[]): Promise<string>;
  ensureQoS(serviceMetrics: any): Promise<boolean>;
  intelligentFailover(failedComponent: string): Promise<void>;
}

/**
 * @class AdaptiveLoadBalancer
 * @description Implements real-time adjustment of worker assignments and dynamic scaling based on predicted demand.
 */
export class AdaptiveLoadBalancer implements AdaptiveBalancingOperations {
  private config: AdaptiveBalancingConfig;
  private logger: Logger;
  private predictiveSystem: PredictiveCoordinationSystem;

  constructor(config: AdaptiveBalancingConfig, predictiveSystem: PredictiveCoordinationSystem) {
    this.config = config;
    this.logger = new Logger('AdaptiveLoadBalancer');
    this.predictiveSystem = predictiveSystem;
    this.logger.info('Adaptive Load Balancer initialized.');
  }

  /**
   * Adjusts worker assignments in real-time based on current load and worker metrics.
   * @param {any} currentLoad Current system load metrics.
   * @param {any[]} workerPool A list of available workers with their current status/load.
   * @returns {Promise<any[]>} Recommended worker assignments.
   */
  public async adjustWorkerAssignments(currentLoad: any, workerPool: any[]): Promise<any[]> {
    this.logger.info('Adjusting worker assignments based on current load...', currentLoad);
    // Use predictive system to get optimal worker recommendations
    const optimalAssignments = await this.predictiveSystem.predictOptimalWorker(currentLoad, workerPool);
    this.logger.debug('Worker assignments adjusted.', optimalAssignments);
    return optimalAssignments;
  }

  /**
   * Triggers dynamic scaling based on predicted demand.
   * @param {any} predictedDemand Data representing the predicted future demand.
   * @returns {Promise<void>}
   */
  public async triggerDynamicScaling(predictedDemand: any): Promise<void> {
    this.logger.info('Triggering dynamic scaling based on predicted demand...', predictedDemand);
    // This would involve interacting with GCP Compute Coordinator to scale GKE, Cloud Run, etc.
    await new Promise(resolve => setTimeout(resolve, 200));
    this.logger.debug('Dynamic scaling triggered.');
  }

  /**
   * Distributes load geographically across Google Cloud regions.
   * @param {any} task The task to distribute.
   * @param {string[]} regions A list of available GCP regions.
   * @returns {Promise<string>} The ID of the region where the task is distributed.
   */
  public async distributeLoadGeographically(task: any, regions: string[]): Promise<string> {
    this.logger.info(`Distributing load geographically for task to regions: ${regions.join(', ')}...`);
    // Use predictive system to determine optimal region based on load, cost, latency
    const optimalRegion = regions[Math.floor(Math.random() * regions.length)]; // Simulated
    this.logger.debug(`Task distributed to region: ${optimalRegion}`);
    return optimalRegion;
  }

  /**
   * Balances load with cost awareness.
   * @param {any} task The task to assign.
   * @param {any[]} workerPool A list of available workers with cost profiles.
   * @returns {Promise<string>} The ID of the worker assigned based on cost optimization.
   */
  public async balanceLoadCostAware(task: any, workerPool: any[]): Promise<string> {
    this.logger.info('Balancing load with cost awareness...', task);
    // Use predictive system or a cost optimization model to select worker
    const costOptimalWorker = workerPool[Math.floor(Math.random() * workerPool.length)]; // Simulated
    this.logger.debug(`Task assigned to cost-optimal worker: ${costOptimalWorker.id}`);
    return costOptimalWorker.id;
  }

  /**
   * Ensures Quality of Service (QoS) guarantees with SLA monitoring.
   * @param {any} serviceMetrics Real-time service metrics.
   * @returns {Promise<boolean>} True if QoS is met, false otherwise.
   */
  public async ensureQoS(serviceMetrics: any): Promise<boolean> {
    this.logger.info('Ensuring QoS guarantees...', serviceMetrics);
    // This would involve comparing current metrics against defined SLAs.
    const qosMet = serviceMetrics.latency < 100 && serviceMetrics.errorRate < 0.01; // Simulated
    this.logger.debug(`QoS met: ${qosMet}`);
    return qosMet;
  }

  /**
   * Implements intelligent failover with minimal coordination disruption.
   * @param {string} failedComponent The component that failed.
   * @returns {Promise<void>}
   */
  public async intelligentFailover(failedComponent: string): Promise<void> {
    this.logger.warn(`Intelligent failover triggered for: ${failedComponent}`);
    // Use predictive system to identify alternative resources or strategies
    await new Promise(resolve => setTimeout(resolve, 300));
    this.logger.debug('Failover completed.');
  }
}