import * as plugins from '../plugins.js';
import { DcRouter } from '../classes.dcrouter.js';

export class MetricsManager {
  private logger: plugins.smartlog.Smartlog;
  private smartMetrics: plugins.smartmetrics.SmartMetrics;
  private dcRouter: DcRouter;
  private resetInterval?: NodeJS.Timeout;
  
  // Constants
  private readonly MAX_TOP_DOMAINS = 1000; // Limit topDomains Map size
  
  // Track email-specific metrics
  private emailMetrics = {
    sentToday: 0,
    receivedToday: 0,
    failedToday: 0,
    bouncedToday: 0,
    queueSize: 0,
    lastResetDate: new Date().toDateString(),
  };
  
  // Track DNS-specific metrics
  private dnsMetrics = {
    totalQueries: 0,
    cacheHits: 0,
    cacheMisses: 0,
    queryTypes: {} as Record<string, number>,
    topDomains: new Map<string, number>(),
    lastResetDate: new Date().toDateString(),
  };
  
  // Track security-specific metrics
  private securityMetrics = {
    blockedIPs: 0,
    authFailures: 0,
    spamDetected: 0,
    malwareDetected: 0,
    phishingDetected: 0,
    lastResetDate: new Date().toDateString(),
  };
  
  constructor(dcRouter: DcRouter) {
    this.dcRouter = dcRouter;
    // Create a new Smartlog instance for metrics
    this.logger = new plugins.smartlog.Smartlog({
      logContext: {
        environment: 'production',
        runtime: 'node',
        zone: 'dcrouter-metrics',
      }
    });
    this.smartMetrics = new plugins.smartmetrics.SmartMetrics(this.logger, 'dcrouter');
  }
  
  public async start(): Promise<void> {
    // Start SmartMetrics collection
    this.smartMetrics.start();
    
    // Reset daily counters at midnight
    this.resetInterval = setInterval(() => {
      const currentDate = new Date().toDateString();
      
      if (currentDate !== this.emailMetrics.lastResetDate) {
        this.emailMetrics.sentToday = 0;
        this.emailMetrics.receivedToday = 0;
        this.emailMetrics.failedToday = 0;
        this.emailMetrics.bouncedToday = 0;
        this.emailMetrics.lastResetDate = currentDate;
      }
      
      if (currentDate !== this.dnsMetrics.lastResetDate) {
        this.dnsMetrics.totalQueries = 0;
        this.dnsMetrics.cacheHits = 0;
        this.dnsMetrics.cacheMisses = 0;
        this.dnsMetrics.queryTypes = {};
        this.dnsMetrics.topDomains.clear();
        this.dnsMetrics.lastResetDate = currentDate;
      }
      
      if (currentDate !== this.securityMetrics.lastResetDate) {
        this.securityMetrics.blockedIPs = 0;
        this.securityMetrics.authFailures = 0;
        this.securityMetrics.spamDetected = 0;
        this.securityMetrics.malwareDetected = 0;
        this.securityMetrics.phishingDetected = 0;
        this.securityMetrics.lastResetDate = currentDate;
      }
    }, 60000); // Check every minute
    
    this.logger.log('info', 'MetricsManager started');
  }
  
  public async stop(): Promise<void> {
    // Clear the reset interval
    if (this.resetInterval) {
      clearInterval(this.resetInterval);
      this.resetInterval = undefined;
    }
    
    this.smartMetrics.stop();
    this.logger.log('info', 'MetricsManager stopped');
  }
  
  // Get server metrics from SmartMetrics and SmartProxy
  public async getServerStats() {
    const smartMetricsData = await this.smartMetrics.getMetrics();
    const proxyStats = this.dcRouter.smartProxy ? this.dcRouter.smartProxy.getStats() : null;
    
    return {
      uptime: process.uptime(),
      startTime: Date.now() - (process.uptime() * 1000),
      memoryUsage: {
        heapUsed: process.memoryUsage().heapUsed,
        heapTotal: process.memoryUsage().heapTotal,
        external: process.memoryUsage().external,
        rss: process.memoryUsage().rss,
      },
      cpuUsage: {
        user: parseFloat(smartMetricsData.cpuUsageText || '0'),
        system: 0, // SmartMetrics doesn't separate user/system
      },
      activeConnections: proxyStats ? proxyStats.getActiveConnections() : 0,
      totalConnections: proxyStats ? proxyStats.getTotalConnections() : 0,
      requestsPerSecond: proxyStats ? proxyStats.getRequestsPerSecond() : 0,
      throughput: proxyStats ? proxyStats.getThroughput() : { bytesIn: 0, bytesOut: 0 },
    };
  }
  
  // Get email metrics
  public async getEmailStats() {
    return {
      sentToday: this.emailMetrics.sentToday,
      receivedToday: this.emailMetrics.receivedToday,
      failedToday: this.emailMetrics.failedToday,
      bounceRate: this.emailMetrics.bouncedToday > 0 
        ? (this.emailMetrics.bouncedToday / this.emailMetrics.sentToday) * 100 
        : 0,
      deliveryRate: this.emailMetrics.sentToday > 0 
        ? ((this.emailMetrics.sentToday - this.emailMetrics.failedToday) / this.emailMetrics.sentToday) * 100 
        : 100,
      queueSize: this.emailMetrics.queueSize,
      averageDeliveryTime: 0, // TODO: Implement when delivery tracking is added
      topRecipients: [], // TODO: Implement recipient tracking
      recentActivity: [], // TODO: Implement activity log
    };
  }
  
  // Get DNS metrics
  public async getDnsStats() {
    const cacheHitRate = this.dnsMetrics.totalQueries > 0 
      ? (this.dnsMetrics.cacheHits / this.dnsMetrics.totalQueries) * 100 
      : 0;
    
    const topDomains = Array.from(this.dnsMetrics.topDomains.entries())
      .sort((a, b) => b[1] - a[1])
      .slice(0, 10)
      .map(([domain, count]) => ({ domain, count }));
    
    return {
      queriesPerSecond: 0, // TODO: Calculate based on time window
      totalQueries: this.dnsMetrics.totalQueries,
      cacheHits: this.dnsMetrics.cacheHits,
      cacheMisses: this.dnsMetrics.cacheMisses,
      cacheHitRate: cacheHitRate,
      topDomains: topDomains,
      queryTypes: this.dnsMetrics.queryTypes,
      averageResponseTime: 0, // TODO: Implement response time tracking
      activeDomains: this.dnsMetrics.topDomains.size,
    };
  }
  
  // Get security metrics
  public async getSecurityStats() {
    return {
      blockedIPs: this.securityMetrics.blockedIPs,
      authFailures: this.securityMetrics.authFailures,
      spamDetected: this.securityMetrics.spamDetected,
      malwareDetected: this.securityMetrics.malwareDetected,
      phishingDetected: this.securityMetrics.phishingDetected,
      totalThreatsBlocked: this.securityMetrics.spamDetected + 
        this.securityMetrics.malwareDetected + 
        this.securityMetrics.phishingDetected,
      recentIncidents: [], // TODO: Implement incident logging
    };
  }
  
  // Get connection info from SmartProxy
  public async getConnectionInfo() {
    const proxyStats = this.dcRouter.smartProxy ? this.dcRouter.smartProxy.getStats() : null;
    
    if (!proxyStats) {
      return [];
    }
    
    const connectionsByRoute = proxyStats.getConnectionsByRoute();
    const connectionInfo = [];
    
    for (const [routeName, count] of connectionsByRoute) {
      connectionInfo.push({
        type: 'https',
        count,
        source: routeName,
        lastActivity: new Date(),
      });
    }
    
    return connectionInfo;
  }
  
  // Email event tracking methods
  public trackEmailSent(): void {
    this.emailMetrics.sentToday++;
  }
  
  public trackEmailReceived(): void {
    this.emailMetrics.receivedToday++;
  }
  
  public trackEmailFailed(): void {
    this.emailMetrics.failedToday++;
  }
  
  public trackEmailBounced(): void {
    this.emailMetrics.bouncedToday++;
  }
  
  public updateQueueSize(size: number): void {
    this.emailMetrics.queueSize = size;
  }
  
  // DNS event tracking methods
  public trackDnsQuery(queryType: string, domain: string, cacheHit: boolean): void {
    this.dnsMetrics.totalQueries++;
    
    if (cacheHit) {
      this.dnsMetrics.cacheHits++;
    } else {
      this.dnsMetrics.cacheMisses++;
    }
    
    // Track query types
    this.dnsMetrics.queryTypes[queryType] = (this.dnsMetrics.queryTypes[queryType] || 0) + 1;
    
    // Track top domains with size limit
    const currentCount = this.dnsMetrics.topDomains.get(domain) || 0;
    this.dnsMetrics.topDomains.set(domain, currentCount + 1);
    
    // If we've exceeded the limit, remove the least accessed domains
    if (this.dnsMetrics.topDomains.size > this.MAX_TOP_DOMAINS) {
      // Convert to array, sort by count, and keep only top domains
      const sortedDomains = Array.from(this.dnsMetrics.topDomains.entries())
        .sort((a, b) => b[1] - a[1])
        .slice(0, Math.floor(this.MAX_TOP_DOMAINS * 0.8)); // Keep 80% to avoid frequent cleanup
      
      // Clear and repopulate with top domains
      this.dnsMetrics.topDomains.clear();
      sortedDomains.forEach(([domain, count]) => {
        this.dnsMetrics.topDomains.set(domain, count);
      });
    }
  }
  
  // Security event tracking methods
  public trackBlockedIP(): void {
    this.securityMetrics.blockedIPs++;
  }
  
  public trackAuthFailure(): void {
    this.securityMetrics.authFailures++;
  }
  
  public trackSpamDetected(): void {
    this.securityMetrics.spamDetected++;
  }
  
  public trackMalwareDetected(): void {
    this.securityMetrics.malwareDetected++;
  }
  
  public trackPhishingDetected(): void {
    this.securityMetrics.phishingDetected++;
  }
}