import { EventEmitter } from 'events';
import { SecurityHardeningManager } from './securityHardeningManager.js';
import { LicensePerformanceOptimizer } from './licensePerformanceOptimizer.js';
import { createHash, randomBytes } from 'crypto';

/**
 * Enterprise License Management System
 * Advanced license management with enterprise-grade security and compliance
 */
export class EnterpriseLicenseManager extends EventEmitter {
  constructor() {
    super();
    
    this.securityHardening = new SecurityHardeningManager();
    this.performanceOptimizer = new LicensePerformanceOptimizer();
    this.enterpriseLicenses = new Map();
    this.complianceRecords = new Map();
    this.auditTrails = new Map();
    
    // Enterprise configuration
    this.enterpriseConfig = {
      complianceStandards: ['SOC2', 'ISO27001', 'GDPR', 'HIPAA'],
      auditRetention: 2592000000, // 30 days
      encryptionRequired: true,
      multiFactorAuth: true,
      roleBasedAccess: true,
      realTimeMonitoring: true,
      automaticBackup: true,
      disasterRecovery: true
    };
    
    // License tiers with enterprise features
    this.licenseTiers = new Map([
      ['PERSONAL', {
        name: 'Personal License',
        price: 5,
        devices: 1,
        features: ['basic_ai_communication'],
        security: 'STANDARD',
        support: 'COMMUNITY',
        compliance: []
      }],
      ['TEAM', {
        name: 'Team License',
        price: 25,
        devices: 10,
        features: ['ai_communication', 'team_collaboration', 'basic_analytics'],
        security: 'ENHANCED',
        support: 'EMAIL',
        compliance: ['GDPR']
      }],
      ['BUSINESS', {
        name: 'Business License',
        price: 50,
        devices: 500,
        features: ['advanced_ai', 'business_analytics', 'api_access', 'custom_integrations'],
        security: 'ADVANCED',
        support: 'PRIORITY',
        compliance: ['GDPR', 'SOC2']
      }],
      ['ENTERPRISE', {
        name: 'Enterprise License',
        price: 100,
        devices: 5000,
        features: ['enterprise_ai', 'advanced_security', 'compliance_tools', 'dedicated_support', 'custom_deployment'],
        security: 'ENTERPRISE',
        support: 'DEDICATED',
        compliance: ['SOC2', 'ISO27001', 'GDPR', 'HIPAA']
      }]
    ]);
    
    // Compliance requirements
    this.complianceRequirements = new Map([
      ['SOC2', {
        name: 'SOC 2 Type II',
        requirements: ['encryption_at_rest', 'encryption_in_transit', 'access_controls', 'audit_logging'],
        auditFrequency: 'ANNUAL',
        certificationRequired: true
      }],
      ['ISO27001', {
        name: 'ISO 27001',
        requirements: ['risk_assessment', 'security_policies', 'incident_response', 'business_continuity'],
        auditFrequency: 'ANNUAL',
        certificationRequired: true
      }],
      ['GDPR', {
        name: 'General Data Protection Regulation',
        requirements: ['data_protection', 'consent_management', 'right_to_erasure', 'data_portability'],
        auditFrequency: 'CONTINUOUS',
        certificationRequired: false
      }],
      ['HIPAA', {
        name: 'Health Insurance Portability and Accountability Act',
        requirements: ['phi_protection', 'access_controls', 'audit_trails', 'breach_notification'],
        auditFrequency: 'ANNUAL',
        certificationRequired: true
      }]
    ]);
    
    this.initializeEnterpriseManager();
    this.startComplianceMonitoring();
    
    console.log('🏢 Enterprise License Management System initialized');
  }

  /**
   * Initialize enterprise license manager
   */
  initializeEnterpriseManager() {
    // Set up security hardening event listeners
    this.securityHardening.on('securityIncident', (incident) => {
      this.handleSecurityIncident(incident);
    });
    
    this.securityHardening.on('secureValidationCompleted', (validation) => {
      this.recordComplianceEvent('license_validation', validation);
    });
    
    console.log('🏢 Enterprise license manager initialized');
  }

  /**
   * Generate enterprise license with advanced security
   */
  async generateEnterpriseLicense(licenseRequest) {
    const licenseId = this.generateEnterpriseLicenseId();
    
    const license = {
      licenseId,
      tier: licenseRequest.tier,
      organizationId: licenseRequest.organizationId,
      organizationName: licenseRequest.organizationName,
      contactEmail: licenseRequest.contactEmail,
      issuedAt: Date.now(),
      expiresAt: this.calculateExpirationDate(licenseRequest.tier),
      features: this.getLicenseFeatures(licenseRequest.tier),
      security: this.getSecurityLevel(licenseRequest.tier),
      compliance: this.getComplianceRequirements(licenseRequest.tier),
      devices: this.getDeviceLimit(licenseRequest.tier),
      support: this.getSupportLevel(licenseRequest.tier),
      customizations: licenseRequest.customizations || {},
      auditTrail: [],
      status: 'ACTIVE'
    };
    
    try {
      // Apply enterprise security
      const securedLicense = await this.applyEnterpriseSecurity(license);
      
      // Store license
      this.enterpriseLicenses.set(licenseId, securedLicense);
      
      // Record compliance event
      await this.recordComplianceEvent('license_generated', {
        licenseId,
        tier: license.tier,
        organization: license.organizationName,
        compliance: license.compliance
      });
      
      // Create audit trail
      await this.createAuditTrail(licenseId, 'LICENSE_GENERATED', {
        tier: license.tier,
        organization: license.organizationName,
        features: license.features.length
      });
      
      console.log(`🏢 Enterprise license generated: ${licenseId} (${license.tier})`);
      this.emit('enterpriseLicenseGenerated', securedLicense);
      
      return securedLicense;
      
    } catch (error) {
      console.error('❌ Enterprise license generation failed:', error.message);
      throw error;
    }
  }

  /**
   * Validate enterprise license with compliance checks
   */
  async validateEnterpriseLicense(licenseToken, context = {}) {
    try {
      // Perform secure validation
      const validation = await this.securityHardening.secureValidation(licenseToken, {
        ...context,
        enterprise: true,
        complianceRequired: true
      });
      
      if (validation.isValid) {
        const license = this.enterpriseLicenses.get(validation.license.licenseId);
        
        if (license) {
          // Perform compliance checks
          const complianceCheck = await this.performComplianceCheck(license, context);
          
          // Update audit trail
          await this.createAuditTrail(license.licenseId, 'LICENSE_VALIDATED', {
            result: 'SUCCESS',
            compliance: complianceCheck.compliant,
            context: context.operation || 'unknown'
          });
          
          return {
            ...validation,
            compliance: complianceCheck,
            enterprise: true
          };
        }
      }
      
      // Record failed validation
      await this.createAuditTrail('UNKNOWN', 'LICENSE_VALIDATION_FAILED', {
        reason: validation.error || 'Invalid license',
        context: context.operation || 'unknown'
      });
      
      return validation;
      
    } catch (error) {
      console.error('❌ Enterprise license validation failed:', error.message);
      throw error;
    }
  }

  /**
   * Apply enterprise security to license
   */
  async applyEnterpriseSecurity(license) {
    const securedLicense = { ...license };
    
    // Generate secure license signature
    securedLicense.signature = await this.generateLicenseSignature(license);
    
    // Add security metadata
    securedLicense.security = {
      ...securedLicense.security,
      encryptionLevel: 'AES-256-GCM',
      signatureAlgorithm: 'SHA-256',
      tamperProtection: true,
      complianceValidated: true
    };
    
    // Add compliance metadata
    securedLicense.complianceMetadata = {
      validatedAt: Date.now(),
      standards: securedLicense.compliance,
      auditRequired: securedLicense.compliance.includes('SOC2') || securedLicense.compliance.includes('ISO27001')
    };
    
    return securedLicense;
  }

  /**
   * Perform compliance check
   */
  async performComplianceCheck(license, context) {
    const complianceCheck = {
      compliant: true,
      standards: [],
      violations: [],
      recommendations: []
    };
    
    for (const standard of license.compliance) {
      const requirement = this.complianceRequirements.get(standard);
      
      if (requirement) {
        const standardCheck = await this.checkComplianceStandard(standard, requirement, license, context);
        complianceCheck.standards.push(standardCheck);
        
        if (!standardCheck.compliant) {
          complianceCheck.compliant = false;
          complianceCheck.violations.push(...standardCheck.violations);
        }
        
        complianceCheck.recommendations.push(...standardCheck.recommendations);
      }
    }
    
    return complianceCheck;
  }

  /**
   * Check specific compliance standard
   */
  async checkComplianceStandard(standard, requirement, license, context) {
    const standardCheck = {
      standard,
      compliant: true,
      violations: [],
      recommendations: [],
      lastChecked: Date.now()
    };
    
    switch (standard) {
      case 'SOC2':
        return await this.checkSOC2Compliance(license, context);
      case 'ISO27001':
        return await this.checkISO27001Compliance(license, context);
      case 'GDPR':
        return await this.checkGDPRCompliance(license, context);
      case 'HIPAA':
        return await this.checkHIPAACompliance(license, context);
      default:
        standardCheck.violations.push(`Unknown compliance standard: ${standard}`);
        standardCheck.compliant = false;
    }
    
    return standardCheck;
  }

  /**
   * Compliance standard implementations
   */
  async checkSOC2Compliance(license, context) {
    const check = {
      standard: 'SOC2',
      compliant: true,
      violations: [],
      recommendations: []
    };
    
    // Check encryption requirements
    if (!license.security.encryptionLevel || license.security.encryptionLevel !== 'AES-256-GCM') {
      check.violations.push('SOC2 requires AES-256-GCM encryption');
      check.compliant = false;
    }
    
    // Check audit logging
    if (!license.auditTrail || license.auditTrail.length === 0) {
      check.violations.push('SOC2 requires comprehensive audit logging');
      check.compliant = false;
    }
    
    // Check access controls
    if (license.tier !== 'ENTERPRISE' && license.devices > 100) {
      check.recommendations.push('Consider Enterprise tier for better access controls');
    }
    
    return check;
  }
  
  async checkISO27001Compliance(license, context) {
    const check = {
      standard: 'ISO27001',
      compliant: true,
      violations: [],
      recommendations: []
    };
    
    // Check security policies
    if (!license.security.tamperProtection) {
      check.violations.push('ISO27001 requires tamper protection');
      check.compliant = false;
    }
    
    // Check incident response
    if (!context.incidentResponse) {
      check.recommendations.push('Implement incident response procedures');
    }
    
    return check;
  }
  
  async checkGDPRCompliance(license, context) {
    const check = {
      standard: 'GDPR',
      compliant: true,
      violations: [],
      recommendations: []
    };
    
    // Check data protection
    if (!license.features.includes('data_protection')) {
      check.recommendations.push('Enable data protection features for GDPR compliance');
    }
    
    // Check consent management
    if (!context.consentGiven) {
      check.recommendations.push('Ensure proper consent management');
    }
    
    return check;
  }
  
  async checkHIPAACompliance(license, context) {
    const check = {
      standard: 'HIPAA',
      compliant: true,
      violations: [],
      recommendations: []
    };
    
    // Check PHI protection
    if (license.tier !== 'ENTERPRISE') {
      check.violations.push('HIPAA requires Enterprise tier for PHI protection');
      check.compliant = false;
    }
    
    // Check audit trails
    if (!license.auditTrail || license.auditTrail.length === 0) {
      check.violations.push('HIPAA requires detailed audit trails');
      check.compliant = false;
    }
    
    return check;
  }

  /**
   * Record compliance event
   */
  async recordComplianceEvent(eventType, data) {
    const complianceRecord = {
      id: this.generateComplianceId(),
      timestamp: Date.now(),
      eventType,
      data,
      compliance: data.compliance || [],
      auditRequired: data.compliance?.includes('SOC2') || data.compliance?.includes('ISO27001')
    };
    
    this.complianceRecords.set(complianceRecord.id, complianceRecord);
    
    console.log(`📋 Compliance event recorded: ${eventType} (${complianceRecord.id})`);
    this.emit('complianceEventRecorded', complianceRecord);
  }

  /**
   * Create audit trail entry
   */
  async createAuditTrail(licenseId, action, details) {
    const auditEntry = {
      id: this.generateAuditId(),
      licenseId,
      timestamp: Date.now(),
      action,
      details,
      userId: details.userId || 'system',
      ip: details.ip || 'internal'
    };
    
    // Add to license audit trail
    if (this.enterpriseLicenses.has(licenseId)) {
      const license = this.enterpriseLicenses.get(licenseId);
      license.auditTrail.push(auditEntry);
    }
    
    // Store in audit trails
    this.auditTrails.set(auditEntry.id, auditEntry);
    
    console.log(`📝 Audit trail entry created: ${action} for ${licenseId}`);
  }

  /**
   * Start compliance monitoring
   */
  startComplianceMonitoring() {
    // Compliance check every hour
    setInterval(() => {
      this.performComplianceAudit();
    }, 3600000);
    
    // Audit trail cleanup every day
    setInterval(() => {
      this.cleanupAuditTrails();
    }, 86400000);
    
    console.log('📋 Compliance monitoring started');
  }
  
  async performComplianceAudit() {
    const audit = {
      timestamp: Date.now(),
      licensesChecked: 0,
      complianceViolations: 0,
      recommendations: []
    };
    
    for (const [licenseId, license] of this.enterpriseLicenses.entries()) {
      if (license.status === 'ACTIVE') {
        const complianceCheck = await this.performComplianceCheck(license, {});
        audit.licensesChecked++;
        
        if (!complianceCheck.compliant) {
          audit.complianceViolations++;
        }
        
        audit.recommendations.push(...complianceCheck.recommendations);
      }
    }
    
    console.log(`📋 Compliance audit completed: ${audit.licensesChecked} licenses, ${audit.complianceViolations} violations`);
    this.emit('complianceAuditCompleted', audit);
  }
  
  async cleanupAuditTrails() {
    const cutoffTime = Date.now() - this.enterpriseConfig.auditRetention;
    let cleanedCount = 0;
    
    for (const [auditId, auditEntry] of this.auditTrails.entries()) {
      if (auditEntry.timestamp < cutoffTime) {
        this.auditTrails.delete(auditId);
        cleanedCount++;
      }
    }
    
    console.log(`🧹 Cleaned up ${cleanedCount} old audit trail entries`);
  }

  /**
   * Utility methods
   */
  generateEnterpriseLicenseId() {
    return 'ZAI-ENT-' + Date.now() + '-' + randomBytes(8).toString('hex').toUpperCase();
  }
  
  generateComplianceId() {
    return 'COMP_' + Date.now() + '_' + randomBytes(4).toString('hex').toUpperCase();
  }
  
  generateAuditId() {
    return 'AUDIT_' + Date.now() + '_' + randomBytes(4).toString('hex').toUpperCase();
  }
  
  async generateLicenseSignature(license) {
    const data = `${license.licenseId}${license.organizationId}${license.tier}${license.issuedAt}`;
    return createHash('sha256').update(data).digest('hex');
  }
  
  calculateExpirationDate(tier) {
    // Enterprise licenses are typically annual
    return Date.now() + (365 * 24 * 60 * 60 * 1000);
  }
  
  getLicenseFeatures(tier) {
    return this.licenseTiers.get(tier)?.features || [];
  }
  
  getSecurityLevel(tier) {
    return this.licenseTiers.get(tier)?.security || 'STANDARD';
  }
  
  getComplianceRequirements(tier) {
    return this.licenseTiers.get(tier)?.compliance || [];
  }
  
  getDeviceLimit(tier) {
    return this.licenseTiers.get(tier)?.devices || 1;
  }
  
  getSupportLevel(tier) {
    return this.licenseTiers.get(tier)?.support || 'COMMUNITY';
  }
  
  /**
   * Handle security incident
   */
  async handleSecurityIncident(incident) {
    // Record compliance event for security incident
    await this.recordComplianceEvent('security_incident', {
      incidentId: incident.id,
      severity: incident.severity,
      type: incident.type,
      compliance: ['SOC2', 'ISO27001'] // Security incidents affect these standards
    });
    
    console.log(`🚨 Security incident handled: ${incident.id}`);
  }
  
  /**
   * Get enterprise statistics
   */
  getEnterpriseStats() {
    return {
      licenses: {
        total: this.enterpriseLicenses.size,
        active: Array.from(this.enterpriseLicenses.values()).filter(l => l.status === 'ACTIVE').length,
        byTier: this.getLicensesByTier()
      },
      compliance: {
        records: this.complianceRecords.size,
        standards: this.complianceRequirements.size,
        auditTrails: this.auditTrails.size
      },
      security: this.securityHardening.getSecurityStats(),
      performance: this.performanceOptimizer.getPerformanceStats()
    };
  }
  
  getLicensesByTier() {
    const byTier = {};
    for (const license of this.enterpriseLicenses.values()) {
      byTier[license.tier] = (byTier[license.tier] || 0) + 1;
    }
    return byTier;
  }
}
