import { EventEmitter } from 'events';
import { createHash, randomBytes } from 'crypto';

/**
 * Autonomous Platform Manager for ZAI Platform
 * Self-healing infrastructure, predictive scaling, and autonomous incident response
 */
export class AutonomousManager extends EventEmitter {
  constructor() {
    super();
    
    this.autonomousAgents = new Map();
    this.healingActions = new Map();
    this.scalingPredictions = new Map();
    this.incidentResponses = new Map();
    this.systemHealth = new Map();
    
    // Autonomous configuration
    this.autonomyConfig = {
      healingEnabled: true,
      scalingEnabled: true,
      incidentResponseEnabled: true,
      learningEnabled: true,
      interventionThreshold: 0.8,
      healingTimeout: 300000, // 5 minutes
      scalingCooldown: 600000, // 10 minutes
      maxAutonomousActions: 10
    };
    
    // AI models for autonomous operations
    this.aiModels = {
      healthPredictor: new HealthPredictionModel(),
      scalingPredictor: new ScalingPredictionModel(),
      incidentClassifier: new IncidentClassificationModel(),
      healingOptimizer: new HealingOptimizationModel(),
      anomalyDetector: new AnomalyDetectionModel()
    };
    
    // System components to monitor
    this.systemComponents = {
      webServer: { status: 'healthy', load: 0.3, lastCheck: Date.now() },
      database: { status: 'healthy', load: 0.2, lastCheck: Date.now() },
      apiGateway: { status: 'healthy', load: 0.4, lastCheck: Date.now() },
      licenseService: { status: 'healthy', load: 0.1, lastCheck: Date.now() },
      analyticsService: { status: 'healthy', load: 0.5, lastCheck: Date.now() },
      securityService: { status: 'healthy', load: 0.3, lastCheck: Date.now() },
      blockchainService: { status: 'healthy', load: 0.2, lastCheck: Date.now() }
    };
    
    this.initializeAutonomousAgents();
    this.startAutonomousMonitoring();
    
    console.log('🤖 Autonomous Platform Manager initialized');
  }

  /**
   * Initialize autonomous agents
   */
  initializeAutonomousAgents() {
    const agents = [
      {
        id: 'health_monitor',
        type: 'HEALTH_MONITORING',
        responsibilities: ['system_health', 'component_monitoring', 'anomaly_detection'],
        interval: 30000, // 30 seconds
        active: true
      },
      {
        id: 'healing_agent',
        type: 'SELF_HEALING',
        responsibilities: ['failure_detection', 'recovery_actions', 'service_restart'],
        interval: 60000, // 1 minute
        active: true
      },
      {
        id: 'scaling_agent',
        type: 'PREDICTIVE_SCALING',
        responsibilities: ['load_prediction', 'resource_scaling', 'capacity_planning'],
        interval: 300000, // 5 minutes
        active: true
      },
      {
        id: 'incident_agent',
        type: 'INCIDENT_RESPONSE',
        responsibilities: ['incident_detection', 'response_coordination', 'escalation'],
        interval: 15000, // 15 seconds
        active: true
      },
      {
        id: 'learning_agent',
        type: 'CONTINUOUS_LEARNING',
        responsibilities: ['pattern_analysis', 'model_optimization', 'strategy_improvement'],
        interval: 3600000, // 1 hour
        active: true
      }
    ];
    
    for (const agentConfig of agents) {
      const agent = {
        ...agentConfig,
        createdAt: Date.now(),
        lastExecution: null,
        executionCount: 0,
        successRate: 1.0,
        averageExecutionTime: 0,
        errors: [],
        actions: []
      };
      
      this.autonomousAgents.set(agent.id, agent);
      
      // Start agent execution
      this.startAgent(agent);
    }
    
    console.log(`🤖 ${agents.length} autonomous agents initialized`);
  }

  /**
   * Start autonomous agent execution
   */
  startAgent(agent) {
    const executeAgent = async () => {
      const startTime = Date.now();
      
      try {
        agent.lastExecution = startTime;
        agent.executionCount++;
        
        let result;
        switch (agent.type) {
          case 'HEALTH_MONITORING':
            result = await this.executeHealthMonitoring();
            break;
          case 'SELF_HEALING':
            result = await this.executeSelfHealing();
            break;
          case 'PREDICTIVE_SCALING':
            result = await this.executePredictiveScaling();
            break;
          case 'INCIDENT_RESPONSE':
            result = await this.executeIncidentResponse();
            break;
          case 'CONTINUOUS_LEARNING':
            result = await this.executeContinuousLearning();
            break;
        }
        
        const executionTime = Date.now() - startTime;
        agent.averageExecutionTime = (agent.averageExecutionTime + executionTime) / 2;
        agent.actions.push({
          timestamp: startTime,
          result,
          executionTime,
          success: true
        });
        
        // Update success rate
        const recentActions = agent.actions.slice(-100);
        const successfulActions = recentActions.filter(a => a.success).length;
        agent.successRate = successfulActions / recentActions.length;
        
        this.emit('agentExecuted', { agentId: agent.id, result, executionTime });
        
      } catch (error) {
        const executionTime = Date.now() - startTime;
        agent.errors.push({
          timestamp: startTime,
          error: error.message,
          executionTime
        });
        
        agent.actions.push({
          timestamp: startTime,
          result: null,
          executionTime,
          success: false,
          error: error.message
        });
        
        console.error(`❌ Agent ${agent.id} execution failed:`, error.message);
        this.emit('agentError', { agentId: agent.id, error: error.message });
      }
    };
    
    // Execute immediately
    executeAgent();
    
    // Schedule recurring execution
    setInterval(executeAgent, agent.interval);
  }

  /**
   * Execute health monitoring
   */
  async executeHealthMonitoring() {
    const healthReport = {
      timestamp: Date.now(),
      overallHealth: 'HEALTHY',
      components: {},
      anomalies: [],
      predictions: {},
      recommendations: []
    };
    
    // Check each system component
    for (const [componentName, component] of Object.entries(this.systemComponents)) {
      const health = await this.checkComponentHealth(componentName, component);
      healthReport.components[componentName] = health;
      
      // Detect anomalies
      const anomalies = await this.aiModels.anomalyDetector.detect(health);
      if (anomalies.length > 0) {
        healthReport.anomalies.push(...anomalies);
      }
      
      // Predict future health
      const prediction = await this.aiModels.healthPredictor.predict(health);
      healthReport.predictions[componentName] = prediction;
      
      // Update component status
      this.systemComponents[componentName] = {
        ...component,
        ...health,
        lastCheck: Date.now()
      };
    }
    
    // Calculate overall health
    const unhealthyComponents = Object.values(healthReport.components)
      .filter(c => c.status !== 'healthy').length;
    
    if (unhealthyComponents === 0) {
      healthReport.overallHealth = 'HEALTHY';
    } else if (unhealthyComponents <= 2) {
      healthReport.overallHealth = 'DEGRADED';
    } else {
      healthReport.overallHealth = 'CRITICAL';
    }
    
    // Generate recommendations
    if (healthReport.anomalies.length > 0) {
      healthReport.recommendations.push('Investigate detected anomalies');
    }
    
    if (healthReport.overallHealth !== 'HEALTHY') {
      healthReport.recommendations.push('Initiate healing procedures');
    }
    
    this.systemHealth.set(Date.now(), healthReport);
    this.emit('healthReportGenerated', healthReport);
    
    return healthReport;
  }

  /**
   * Execute self-healing procedures
   */
  async executeSelfHealing() {
    const healingReport = {
      timestamp: Date.now(),
      actionsPerformed: [],
      componentsHealed: [],
      failedActions: [],
      overallSuccess: true
    };
    
    // Get latest health report
    const latestHealth = Array.from(this.systemHealth.values()).pop();
    
    if (!latestHealth || latestHealth.overallHealth === 'HEALTHY') {
      return { message: 'No healing required - system healthy' };
    }
    
    // Identify components needing healing
    const unhealthyComponents = Object.entries(latestHealth.components)
      .filter(([name, health]) => health.status !== 'healthy');
    
    for (const [componentName, health] of unhealthyComponents) {
      try {
        const healingAction = await this.performHealingAction(componentName, health);
        healingReport.actionsPerformed.push(healingAction);
        
        if (healingAction.success) {
          healingReport.componentsHealed.push(componentName);
        } else {
          healingReport.failedActions.push({
            component: componentName,
            action: healingAction.action,
            error: healingAction.error
          });
        }
        
      } catch (error) {
        healingReport.failedActions.push({
          component: componentName,
          action: 'unknown',
          error: error.message
        });
        healingReport.overallSuccess = false;
      }
    }
    
    this.emit('healingCompleted', healingReport);
    return healingReport;
  }

  /**
   * Execute predictive scaling
   */
  async executePredictiveScaling() {
    const scalingReport = {
      timestamp: Date.now(),
      predictions: {},
      scalingActions: [],
      recommendations: []
    };
    
    // Analyze current load patterns
    const loadPatterns = await this.analyzeLoadPatterns();
    
    // Predict future load for each component
    for (const [componentName, component] of Object.entries(this.systemComponents)) {
      const prediction = await this.aiModels.scalingPredictor.predict({
        component: componentName,
        currentLoad: component.load,
        historicalData: loadPatterns[componentName] || [],
        timeHorizon: 3600000 // 1 hour
      });
      
      scalingReport.predictions[componentName] = prediction;
      
      // Determine if scaling is needed
      if (prediction.predictedLoad > 0.8) {
        const scalingAction = await this.performScalingAction(componentName, 'SCALE_UP', prediction);
        scalingReport.scalingActions.push(scalingAction);
      } else if (prediction.predictedLoad < 0.2 && component.load > 0.3) {
        const scalingAction = await this.performScalingAction(componentName, 'SCALE_DOWN', prediction);
        scalingReport.scalingActions.push(scalingAction);
      }
    }
    
    // Generate capacity planning recommendations
    scalingReport.recommendations = await this.generateCapacityRecommendations(scalingReport.predictions);
    
    this.emit('scalingCompleted', scalingReport);
    return scalingReport;
  }

  /**
   * Execute incident response
   */
  async executeIncidentResponse() {
    const incidentReport = {
      timestamp: Date.now(),
      incidentsDetected: [],
      responsesTriggered: [],
      escalations: []
    };
    
    // Detect incidents
    const incidents = await this.detectIncidents();
    
    for (const incident of incidents) {
      incidentReport.incidentsDetected.push(incident);
      
      // Classify incident severity
      const classification = await this.aiModels.incidentClassifier.classify(incident);
      incident.severity = classification.severity;
      incident.category = classification.category;
      
      // Trigger appropriate response
      const response = await this.triggerIncidentResponse(incident);
      incidentReport.responsesTriggered.push(response);
      
      // Escalate if necessary
      if (incident.severity === 'CRITICAL' || response.requiresEscalation) {
        const escalation = await this.escalateIncident(incident, response);
        incidentReport.escalations.push(escalation);
      }
    }
    
    this.emit('incidentResponseCompleted', incidentReport);
    return incidentReport;
  }

  /**
   * Execute continuous learning
   */
  async executeContinuousLearning() {
    const learningReport = {
      timestamp: Date.now(),
      modelsUpdated: [],
      patternsLearned: [],
      strategiesOptimized: [],
      performanceImprovements: {}
    };
    
    // Analyze recent system behavior
    const recentData = await this.gatherRecentSystemData();
    
    // Update AI models with new data
    for (const [modelName, model] of Object.entries(this.aiModels)) {
      try {
        const updateResult = await model.updateWithNewData(recentData);
        learningReport.modelsUpdated.push({
          model: modelName,
          improvement: updateResult.improvement,
          accuracy: updateResult.accuracy
        });
      } catch (error) {
        console.warn(`⚠️ Failed to update model ${modelName}:`, error.message);
      }
    }
    
    // Learn new patterns
    const patterns = await this.discoverNewPatterns(recentData);
    learningReport.patternsLearned = patterns;
    
    // Optimize autonomous strategies
    const optimizations = await this.optimizeAutonomousStrategies();
    learningReport.strategiesOptimized = optimizations;
    
    // Measure performance improvements
    learningReport.performanceImprovements = await this.measurePerformanceImprovements();
    
    this.emit('learningCompleted', learningReport);
    return learningReport;
  }

  /**
   * Utility methods
   */
  async checkComponentHealth(componentName, component) {
    // Simulate component health check
    const baseHealth = {
      status: 'healthy',
      load: component.load + (Math.random() - 0.5) * 0.1,
      responseTime: 50 + Math.random() * 100,
      errorRate: Math.random() * 0.01,
      uptime: 0.999,
      lastError: null
    };
    
    // Introduce occasional issues for testing
    if (Math.random() < 0.05) { // 5% chance of issues
      baseHealth.status = 'degraded';
      baseHealth.errorRate = 0.05 + Math.random() * 0.1;
      baseHealth.responseTime *= 2;
    }
    
    return baseHealth;
  }
  
  async performHealingAction(componentName, health) {
    const healingActions = {
      'webServer': ['restart_service', 'clear_cache', 'reload_config'],
      'database': ['optimize_queries', 'rebuild_indexes', 'restart_service'],
      'apiGateway': ['restart_service', 'clear_rate_limits', 'reload_routes'],
      'licenseService': ['restart_service', 'clear_cache', 'validate_licenses'],
      'analyticsService': ['restart_service', 'clear_cache', 'rebuild_metrics'],
      'securityService': ['restart_service', 'update_rules', 'clear_blocks'],
      'blockchainService': ['restart_service', 'sync_blockchain', 'validate_blocks']
    };
    
    const availableActions = healingActions[componentName] || ['restart_service'];
    const action = availableActions[Math.floor(Math.random() * availableActions.length)];
    
    // Simulate healing action
    const success = Math.random() > 0.2; // 80% success rate
    
    const healingAction = {
      component: componentName,
      action,
      timestamp: Date.now(),
      success,
      duration: 1000 + Math.random() * 5000,
      error: success ? null : 'Simulated healing failure'
    };
    
    if (success) {
      // Update component status
      this.systemComponents[componentName].status = 'healthy';
      this.systemComponents[componentName].load *= 0.8; // Reduce load
    }
    
    this.healingActions.set(Date.now(), healingAction);
    
    console.log(`🔧 Healing action: ${action} on ${componentName} - ${success ? 'SUCCESS' : 'FAILED'}`);
    
    return healingAction;
  }
  
  async analyzeLoadPatterns() {
    // Simulate load pattern analysis
    const patterns = {};
    
    for (const componentName of Object.keys(this.systemComponents)) {
      patterns[componentName] = Array.from({ length: 24 }, (_, i) => ({
        hour: i,
        averageLoad: 0.2 + Math.sin(i / 24 * 2 * Math.PI) * 0.3 + Math.random() * 0.1
      }));
    }
    
    return patterns;
  }
  
  async performScalingAction(componentName, action, prediction) {
    const scalingAction = {
      component: componentName,
      action,
      timestamp: Date.now(),
      prediction,
      success: Math.random() > 0.1, // 90% success rate
      newCapacity: action === 'SCALE_UP' ? 
        this.systemComponents[componentName].capacity * 1.5 : 
        this.systemComponents[componentName].capacity * 0.8
    };
    
    if (scalingAction.success) {
      console.log(`📈 Scaling action: ${action} on ${componentName}`);
    }
    
    return scalingAction;
  }
  
  async generateCapacityRecommendations(predictions) {
    const recommendations = [];
    
    for (const [component, prediction] of Object.entries(predictions)) {
      if (prediction.predictedLoad > 0.9) {
        recommendations.push({
          component,
          recommendation: 'Consider permanent capacity increase',
          priority: 'HIGH',
          estimatedCost: '$100-500/month'
        });
      }
    }
    
    return recommendations;
  }
  
  async detectIncidents() {
    const incidents = [];
    
    // Check for system-wide issues
    const latestHealth = Array.from(this.systemHealth.values()).pop();
    
    if (latestHealth && latestHealth.overallHealth === 'CRITICAL') {
      incidents.push({
        id: this.generateIncidentId(),
        type: 'SYSTEM_CRITICAL',
        description: 'Multiple system components are unhealthy',
        timestamp: Date.now(),
        affectedComponents: Object.keys(latestHealth.components)
          .filter(c => latestHealth.components[c].status !== 'healthy')
      });
    }
    
    return incidents;
  }
  
  async triggerIncidentResponse(incident) {
    const response = {
      incidentId: incident.id,
      responseId: this.generateResponseId(),
      timestamp: Date.now(),
      actions: [],
      requiresEscalation: incident.severity === 'CRITICAL'
    };
    
    // Determine response actions based on incident type
    switch (incident.type) {
      case 'SYSTEM_CRITICAL':
        response.actions = ['notify_administrators', 'initiate_healing', 'scale_resources'];
        break;
      default:
        response.actions = ['log_incident', 'monitor_closely'];
    }
    
    console.log(`🚨 Incident response triggered: ${incident.type}`);
    
    return response;
  }
  
  async escalateIncident(incident, response) {
    const escalation = {
      incidentId: incident.id,
      responseId: response.responseId,
      escalationId: this.generateEscalationId(),
      timestamp: Date.now(),
      escalatedTo: 'OPERATIONS_TEAM',
      reason: 'Critical incident requiring human intervention'
    };
    
    console.log(`📢 Incident escalated: ${incident.id}`);
    
    return escalation;
  }
  
  async gatherRecentSystemData() {
    // Simulate gathering recent system data
    return {
      healthReports: Array.from(this.systemHealth.values()).slice(-100),
      healingActions: Array.from(this.healingActions.values()).slice(-50),
      scalingActions: Array.from(this.scalingPredictions.values()).slice(-20)
    };
  }
  
  async discoverNewPatterns(data) {
    // Simulate pattern discovery
    return [
      {
        pattern: 'High load correlation between webServer and database',
        confidence: 0.85,
        actionable: true
      }
    ];
  }
  
  async optimizeAutonomousStrategies() {
    // Simulate strategy optimization
    return [
      {
        strategy: 'healing_timeout',
        oldValue: this.autonomyConfig.healingTimeout,
        newValue: this.autonomyConfig.healingTimeout * 0.9,
        improvement: '10% faster healing'
      }
    ];
  }
  
  async measurePerformanceImprovements() {
    return {
      healingSuccessRate: 0.85,
      scalingAccuracy: 0.78,
      incidentResponseTime: 45, // seconds
      overallSystemUptime: 0.999
    };
  }
  
  generateIncidentId() {
    return 'INC_' + Date.now() + '_' + randomBytes(4).toString('hex').toUpperCase();
  }
  
  generateResponseId() {
    return 'RSP_' + Date.now() + '_' + randomBytes(4).toString('hex').toUpperCase();
  }
  
  generateEscalationId() {
    return 'ESC_' + Date.now() + '_' + randomBytes(4).toString('hex').toUpperCase();
  }
  
  /**
   * Start autonomous monitoring
   */
  startAutonomousMonitoring() {
    console.log('🤖 Autonomous monitoring started');
    this.emit('autonomousMonitoringStarted');
  }
  
  /**
   * Get autonomous system statistics
   */
  getAutonomousStats() {
    const agents = Array.from(this.autonomousAgents.values());
    
    return {
      agents: {
        total: agents.length,
        active: agents.filter(a => a.active).length,
        averageSuccessRate: agents.reduce((sum, a) => sum + a.successRate, 0) / agents.length
      },
      healing: {
        totalActions: this.healingActions.size,
        successRate: Array.from(this.healingActions.values())
          .filter(a => a.success).length / this.healingActions.size
      },
      scaling: {
        totalPredictions: this.scalingPredictions.size,
        accuracy: 0.78 // Simulated accuracy
      },
      incidents: {
        totalResponses: this.incidentResponses.size,
        averageResponseTime: 45 // seconds
      },
      systemHealth: {
        overallHealth: this.getOverallSystemHealth(),
        componentsMonitored: Object.keys(this.systemComponents).length
      }
    };
  }
  
  getOverallSystemHealth() {
    const latestHealth = Array.from(this.systemHealth.values()).pop();
    return latestHealth ? latestHealth.overallHealth : 'UNKNOWN';
  }
}

// Simplified AI Model Classes
class HealthPredictionModel {
  async predict(health) {
    return {
      predictedStatus: health.status,
      confidence: 0.85,
      timeHorizon: 3600000 // 1 hour
    };
  }
  
  async updateWithNewData(data) {
    return { improvement: 0.02, accuracy: 0.87 };
  }
}

class ScalingPredictionModel {
  async predict(data) {
    return {
      predictedLoad: data.currentLoad + (Math.random() - 0.5) * 0.2,
      confidence: 0.78,
      timeHorizon: data.timeHorizon
    };
  }
  
  async updateWithNewData(data) {
    return { improvement: 0.03, accuracy: 0.80 };
  }
}

class IncidentClassificationModel {
  async classify(incident) {
    const severities = ['LOW', 'MEDIUM', 'HIGH', 'CRITICAL'];
    const categories = ['PERFORMANCE', 'AVAILABILITY', 'SECURITY', 'DATA'];
    
    return {
      severity: severities[Math.floor(Math.random() * severities.length)],
      category: categories[Math.floor(Math.random() * categories.length)],
      confidence: 0.82
    };
  }
  
  async updateWithNewData(data) {
    return { improvement: 0.01, accuracy: 0.84 };
  }
}

class HealingOptimizationModel {
  async optimize(healingAction) {
    return {
      optimizedAction: healingAction,
      expectedSuccessRate: 0.9,
      estimatedDuration: 2000
    };
  }
  
  async updateWithNewData(data) {
    return { improvement: 0.05, accuracy: 0.88 };
  }
}

class AnomalyDetectionModel {
  async detect(health) {
    const anomalies = [];
    
    if (health.responseTime > 200) {
      anomalies.push({
        type: 'HIGH_RESPONSE_TIME',
        severity: 'MEDIUM',
        value: health.responseTime,
        threshold: 200
      });
    }
    
    if (health.errorRate > 0.05) {
      anomalies.push({
        type: 'HIGH_ERROR_RATE',
        severity: 'HIGH',
        value: health.errorRate,
        threshold: 0.05
      });
    }
    
    return anomalies;
  }
  
  async updateWithNewData(data) {
    return { improvement: 0.04, accuracy: 0.76 };
  }
}
