claude-flow-tbowman01/src/enterprise/audit-manager.ts

Enterprise-grade AI agent orchestration with ruv-swarm integration (Alpha Release)

import { EventEmitter } from 'events';
import { writeFile, readFile, mkdir, readdir } from 'fs/promises';
import { join } from 'path';
import { createHash } from 'crypto';
import { Logger } from '../core/logger.js';
import { ConfigManager } from '../core/config.js';

export interface AuditEntry {
  id: string;
  timestamp: Date;
  eventType: string;
  category:
    | 'authentication'
    | 'authorization'
    | 'data-access'
    | 'system-change'
    | 'security'
    | 'compliance'
    | 'business';
  severity: 'low' | 'medium' | 'high' | 'critical';
  userId?: string;
  sessionId?: string;
  resource: {
    type: string;
    id: string;
    name?: string;
    path?: string;
  };
  action: string;
  outcome: 'success' | 'failure' | 'partial' | 'denied';
  details: Record<string, any>;
  context: {
    ipAddress?: string;
    userAgent?: string;
    location?: string;
    source: string;
    requestId?: string;
  };
  compliance: {
    frameworks: string[];
    controls: string[];
    retention: string;
    classification: 'public' | 'internal' | 'confidential' | 'restricted';
  };
  integrity: {
    hash: string;
    signature?: string;
    verified: boolean;
  };
  metadata: Record<string, any>;
}

export interface ComplianceFramework {
  id: string;
  name: string;
  version: string;
  description: string;
  type: 'regulatory' | 'industry' | 'internal' | 'certification';
  requirements: ComplianceRequirement[];
  auditFrequency: 'continuous' | 'daily' | 'weekly' | 'monthly' | 'quarterly' | 'annually';
  retentionPeriod: string;
  reportingRequirements: {
    frequency: string;
    recipients: string[];
    format: string[];
    automated: boolean;
  };
  controls: ComplianceControl[];
  status: 'active' | 'inactive' | 'pending' | 'deprecated';
  implementationDate: Date;
  nextReview: Date;
  responsible: string;
}

export interface ComplianceRequirement {
  id: string;
  title: string;
  description: string;
  category: string;
  priority: 'low' | 'medium' | 'high' | 'critical';
  status: 'compliant' | 'non-compliant' | 'partial' | 'not-applicable' | 'pending';
  evidence: string[];
  gaps: string[];
  remediation: {
    actions: string[];
    owner: string;
    dueDate: Date;
    cost?: number;
    effort?: string;
  };
  lastAssessed: Date;
  nextAssessment: Date;
  automatedCheck: {
    enabled: boolean;
    frequency: string;
    query: string;
    threshold?: any;
  };
}

export interface ComplianceControl {
  id: string;
  name: string;
  description: string;
  type: 'preventive' | 'detective' | 'corrective' | 'compensating';
  automationType: 'manual' | 'semi-automated' | 'automated';
  effectiveness: 'low' | 'medium' | 'high';
  frequency: string;
  owner: string;
  evidence: string[];
  testingProcedure: string;
  lastTested: Date;
  nextTest: Date;
  status: 'effective' | 'ineffective' | 'needs-improvement' | 'not-tested';
}

export interface AuditReport {
  id: string;
  title: string;
  description: string;
  type: 'compliance' | 'security' | 'operational' | 'financial' | 'investigation' | 'custom';
  scope: {
    timeRange: { start: Date; end: Date };
    systems: string[];
    users: string[];
    events: string[];
    compliance: string[];
  };
  findings: AuditFinding[];
  recommendations: AuditRecommendation[];
  summary: {
    totalEvents: number;
    criticalFindings: number;
    complianceScore: number;
    riskLevel: 'low' | 'medium' | 'high' | 'critical';
  };
  methodology: string;
  limitations: string[];
  reviewers: string[];
  approvers: string[];
  status: 'draft' | 'under-review' | 'approved' | 'published' | 'archived';
  confidentiality: 'public' | 'internal' | 'confidential' | 'restricted';
  createdAt: Date;
  updatedAt: Date;
  createdBy: string;
  publishedAt?: Date;
}

export interface AuditFinding {
  id: string;
  title: string;
  description: string;
  severity: 'low' | 'medium' | 'high' | 'critical';
  category: string;
  risk: string;
  impact: string;
  likelihood: string;
  evidence: AuditEvidence[];
  relatedEvents: string[];
  complianceImpact: {
    frameworks: string[];
    violations: string[];
    penalties?: string[];
  };
  remediation: {
    priority: 'low' | 'medium' | 'high' | 'immediate';
    owner: string;
    actions: string[];
    timeline: string;
    cost?: number;
  };
  status: 'open' | 'in-progress' | 'resolved' | 'accepted-risk' | 'false-positive';
}

export interface AuditEvidence {
  id: string;
  type:
    | 'log-entry'
    | 'screenshot'
    | 'document'
    | 'system-output'
    | 'witness-statement'
    | 'data-export';
  description: string;
  source: string;
  timestamp: Date;
  hash: string;
  location: string;
  preservationStatus: 'intact' | 'modified' | 'corrupted' | 'missing';
  chainOfCustody: ChainOfCustodyEntry[];
}

export interface ChainOfCustodyEntry {
  timestamp: Date;
  action: 'collected' | 'accessed' | 'analyzed' | 'transferred' | 'stored' | 'destroyed';
  user: string;
  reason: string;
  hash: string;
}

export interface AuditRecommendation {
  id: string;
  title: string;
  description: string;
  priority: 'low' | 'medium' | 'high' | 'critical';
  category: 'policy' | 'process' | 'technology' | 'training' | 'governance';
  implementation: {
    effort: 'low' | 'medium' | 'high';
    cost: 'low' | 'medium' | 'high';
    timeline: string;
    dependencies: string[];
    risks: string[];
  };
  expectedBenefit: string;
  owner: string;
  status: 'proposed' | 'approved' | 'in-progress' | 'completed' | 'rejected';
  tracking: {
    milestones: string[];
    progress: number;
    nextReview: Date;
  };
}

export interface AuditTrail {
  id: string;
  name: string;
  description: string;
  category: string;
  entries: AuditEntry[];
  configuration: {
    retention: string;
    compression: boolean;
    encryption: boolean;
    archival: {
      enabled: boolean;
      location: string;
      schedule: string;
    };
    monitoring: {
      realTime: boolean;
      alerting: boolean;
      dashboards: string[];
    };
  };
  integrity: {
    verified: boolean;
    lastVerification: Date;
    checksum: string;
    tamperEvidence: TamperEvidence[];
  };
  access: {
    viewers: string[];
    admins: string[];
    readonly: boolean;
    auditAccess: boolean;
  };
  compliance: {
    frameworks: string[];
    retention: string;
    exportRequirements: string[];
    immutable: boolean;
  };
  createdAt: Date;
  updatedAt: Date;
}

export interface TamperEvidence {
  timestamp: Date;
  type: 'checksum-mismatch' | 'unauthorized-access' | 'missing-entries' | 'timestamp-anomaly';
  description: string;
  severity: 'low' | 'medium' | 'high' | 'critical';
  investigationStatus: 'pending' | 'investigating' | 'resolved' | 'false-alarm';
  evidence: string[];
}

export interface AuditConfiguration {
  general: {
    enabled: boolean;
    defaultRetention: string;
    compressionEnabled: boolean;
    encryptionEnabled: boolean;
    realTimeProcessing: boolean;
  };
  collection: {
    automaticCapture: boolean;
    bufferSize: number;
    batchSize: number;
    flushInterval: number;
    failureHandling: 'ignore' | 'retry' | 'alert' | 'stop';
  };
  storage: {
    primaryLocation: string;
    backupLocation?: string;
    archivalLocation?: string;
    partitioning: 'daily' | 'weekly' | 'monthly';
    indexing: boolean;
  };
  integrity: {
    checksumAlgorithm: 'sha256' | 'sha512' | 'blake2b';
    verificationFrequency: string;
    digitalSignatures: boolean;
    immutableStorage: boolean;
  };
  compliance: {
    frameworks: string[];
    automaticClassification: boolean;
    retentionPolicies: Record<string, string>;
    exportFormats: string[];
  };
  monitoring: {
    alerting: {
      enabled: boolean;
      channels: string[];
      thresholds: {
        failedLogins: number;
        privilegedAccess: number;
        dataExfiltration: number;
        configChanges: number;
      };
    };
    reporting: {
      automated: boolean;
      frequency: string;
      recipients: string[];
      dashboards: string[];
    };
  };
  privacy: {
    piiDetection: boolean;
    anonymization: boolean;
    masking: {
      enabled: boolean;
      patterns: string[];
    };
    consent: {
      required: boolean;
      tracking: boolean;
    };
  };
}

export interface AuditMetrics {
  volume: {
    totalEntries: number;
    dailyAverage: number;
    peakHourly: number;
    byCategory: Record<string, number>;
    bySeverity: Record<string, number>;
  };
  compliance: {
    overallScore: number;
    byFramework: Record<
      string,
      {
        score: number;
        compliant: number;
        nonCompliant: number;
        total: number;
      }
    >;
    trending: 'improving' | 'stable' | 'declining';
  };
  integrity: {
    verificationSuccess: number;
    tamperAttempts: number;
    dataLoss: number;
    corruptionEvents: number;
  };
  performance: {
    ingestionRate: number;
    queryResponseTime: number;
    storageEfficiency: number;
    availabilityPercentage: number;
  };
  security: {
    unauthorizedAccess: number;
    privilegedActions: number;
    suspiciousPatterns: number;
    escalatedIncidents: number;
  };
}

export class AuditManager extends EventEmitter {
  private auditTrails: Map<string, AuditTrail> = new Map();
  private frameworks: Map<string, ComplianceFramework> = new Map();
  private reports: Map<string, AuditReport> = new Map();
  private auditBuffer: AuditEntry[] = [];
  private auditPath: string;
  private logger: Logger;
  private config: ConfigManager;
  private configuration: AuditConfiguration;

  constructor(auditPath: string = './audit', logger?: Logger, config?: ConfigManager) {
    super();
    this.auditPath = auditPath;
    this.logger = logger || new Logger({ level: 'info', format: 'text', destination: 'console' });
    this.config = config || ConfigManager.getInstance();
    this.configuration = this.getDefaultConfiguration();
  }

  async initialize(): Promise<void> {
    try {
      await mkdir(this.auditPath, { recursive: true });
      await mkdir(join(this.auditPath, 'trails'), { recursive: true });
      await mkdir(join(this.auditPath, 'frameworks'), { recursive: true });
      await mkdir(join(this.auditPath, 'reports'), { recursive: true });
      await mkdir(join(this.auditPath, 'evidence'), { recursive: true });
      await mkdir(join(this.auditPath, 'exports'), { recursive: true });

      await this.loadConfigurations();
      await this.initializeDefaultFrameworks();
      await this.startAuditProcessing();

      this.logger.info('Audit Manager initialized successfully');
    } catch (error) {
      this.logger.error('Failed to initialize Audit Manager', { error });
      throw error;
    }
  }

  async logAuditEvent(eventData: {
    eventType: string;
    category: AuditEntry['category'];
    severity?: AuditEntry['severity'];
    userId?: string;
    sessionId?: string;
    resource: AuditEntry['resource'];
    action: string;
    outcome: AuditEntry['outcome'];
    details: Record<string, any>;
    context: Partial<AuditEntry['context']>;
    compliance?: {
      frameworks?: string[];
      controls?: string[];
      classification?: AuditEntry['compliance']['classification'];
    };
  }): Promise<AuditEntry> {
    const entry: AuditEntry = {
      id: `audit-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
      timestamp: new Date(),
      eventType: eventData.eventType,
      category: eventData.category,
      severity: eventData.severity || 'medium',
      userId: eventData.userId,
      sessionId: eventData.sessionId,
      resource: eventData.resource,
      action: eventData.action,
      outcome: eventData.outcome,
      details: eventData.details,
      context: {
        source: 'system',
        ...eventData.context,
      },
      compliance: {
        frameworks: eventData.compliance?.frameworks || [],
        controls: eventData.compliance?.controls || [],
        retention: this.calculateRetentionPeriod(
          eventData.category,
          eventData.compliance?.frameworks,
        ),
        classification: eventData.compliance?.classification || 'internal',
      },
      integrity: {
        hash: '',
        verified: false,
      },
      metadata: {},
    };

    // Calculate integrity hash
    entry.integrity.hash = this.calculateHash(entry);
    entry.integrity.verified = true;

    // Add to buffer for batch processing
    this.auditBuffer.push(entry);

    // Immediate processing for critical events
    if (entry.severity === 'critical') {
      await this.processAuditEntry(entry);
      await this.generateSecurityAlert(entry);
    }

    // Batch process if buffer is full
    if (this.auditBuffer.length >= this.configuration.collection.batchSize) {
      await this.flushAuditBuffer();
    }

    this.emit('audit:logged', entry);
    return entry;
  }

  async createComplianceFramework(frameworkData: {
    name: string;
    version: string;
    description: string;
    type: ComplianceFramework['type'];
    requirements: Omit<ComplianceRequirement, 'id'>[];
    controls: Omit<ComplianceControl, 'id'>[];
    auditFrequency: ComplianceFramework['auditFrequency'];
    retentionPeriod: string;
    responsible: string;
  }): Promise<ComplianceFramework> {
    const framework: ComplianceFramework = {
      id: `framework-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
      name: frameworkData.name,
      version: frameworkData.version,
      description: frameworkData.description,
      type: frameworkData.type,
      requirements: frameworkData.requirements.map((req, index) => ({
        id: `req-${Date.now()}-${index}`,
        ...req,
        automatedCheck: {
          enabled: false,
          frequency: 'daily',
          query: '',
          ...req.automatedCheck,
        },
      })),
      auditFrequency: frameworkData.auditFrequency,
      retentionPeriod: frameworkData.retentionPeriod,
      reportingRequirements: {
        frequency: 'quarterly',
        recipients: [],
        format: ['pdf', 'json'],
        automated: false,
      },
      controls: frameworkData.controls.map((control, index) => ({
        id: `control-${Date.now()}-${index}`,
        ...control,
      })),
      status: 'active',
      implementationDate: new Date(),
      nextReview: new Date(Date.now() + 365 * 24 * 60 * 60 * 1000), // 1 year
      responsible: frameworkData.responsible,
    };

    this.frameworks.set(framework.id, framework);
    await this.saveFramework(framework);

    await this.logAuditEvent({
      eventType: 'compliance_framework_created',
      category: 'compliance',
      severity: 'medium',
      resource: { type: 'compliance-framework', id: framework.id, name: framework.name },
      action: 'create',
      outcome: 'success',
      details: { frameworkType: framework.type, requirementsCount: framework.requirements.length },
      context: { source: 'audit-manager' },
      compliance: { frameworks: [framework.id] },
    });

    this.emit('framework:created', framework);
    this.logger.info(`Compliance framework created: ${framework.name} (${framework.id})`);

    return framework;
  }

  async generateAuditReport(reportConfig: {
    title: string;
    description: string;
    type: AuditReport['type'];
    scope: AuditReport['scope'];
    includeRecommendations?: boolean;
    confidentiality?: AuditReport['confidentiality'];
  }): Promise<AuditReport> {
    const report: AuditReport = {
      id: `report-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
      title: reportConfig.title,
      description: reportConfig.description,
      type: reportConfig.type,
      scope: reportConfig.scope,
      findings: [],
      recommendations: [],
      summary: {
        totalEvents: 0,
        criticalFindings: 0,
        complianceScore: 0,
        riskLevel: 'low',
      },
      methodology: 'Automated analysis of audit trail data with manual review of findings',
      limitations: [],
      reviewers: [],
      approvers: [],
      status: 'draft',
      confidentiality: reportConfig.confidentiality || 'internal',
      createdAt: new Date(),
      updatedAt: new Date(),
      createdBy: 'audit-manager',
    };

    // Collect relevant audit entries
    const auditEntries = await this.queryAuditEntries(reportConfig.scope);
    report.summary.totalEvents = auditEntries.length;

    // Analyze entries for findings
    const findings = await this.analyzeAuditEntries(auditEntries, reportConfig.type);
    report.findings = findings;
    report.summary.criticalFindings = findings.filter((f) => f.severity === 'critical').length;

    // Calculate compliance score
    if (reportConfig.scope.compliance && reportConfig.scope.compliance.length > 0) {
      report.summary.complianceScore = await this.calculateComplianceScore(
        reportConfig.scope.compliance,
        auditEntries,
      );
    }

    // Determine risk level
    report.summary.riskLevel = this.calculateRiskLevel(findings);

    // Generate recommendations
    if (reportConfig.includeRecommendations !== false) {
      report.recommendations = await this.generateRecommendations(findings, reportConfig.type);
    }

    this.reports.set(report.id, report);
    await this.saveReport(report);

    await this.logAuditEvent({
      eventType: 'audit_report_generated',
      category: 'compliance',
      severity: 'medium',
      resource: { type: 'audit-report', id: report.id, name: report.title },
      action: 'generate',
      outcome: 'success',
      details: {
        reportType: report.type,
        totalEvents: report.summary.totalEvents,
        findingsCount: report.findings.length,
        complianceScore: report.summary.complianceScore,
      },
      context: { source: 'audit-manager' },
      compliance: { frameworks: reportConfig.scope.compliance || [] },
    });

    this.emit('report:generated', report);
    this.logger.info(`Audit report generated: ${report.title} (${report.id})`);

    return report;
  }

  async exportAuditData(exportConfig: {
    format: 'json' | 'csv' | 'xml' | 'pdf';
    scope: {
      timeRange: { start: Date; end: Date };
      categories?: string[];
      severity?: string[];
      users?: string[];
    };
    destination: string;
    encryption?: boolean;
    compression?: boolean;
  }): Promise<string> {
    const entries = await this.queryAuditEntries(exportConfig.scope);

    let exportData: string;
    const timestamp = new Date().toISOString().replace(/[:.]/g, '-');
    const filename = `audit-export-${timestamp}.${exportConfig.format}`;
    const filepath = join(this.auditPath, 'exports', filename);

    switch (exportConfig.format) {
      case 'json':
        exportData = JSON.stringify(entries, null, 2);
        break;
      case 'csv':
        exportData = this.convertToCSV(entries);
        break;
      case 'xml':
        exportData = this.convertToXML(entries);
        break;
      case 'pdf':
        exportData = await this.convertToPDF(entries);
        break;
      default:
        throw new Error(`Unsupported export format: ${exportConfig.format}`);
    }

    // Apply compression if requested
    if (exportConfig.compression) {
      // Would implement compression here
    }

    // Apply encryption if requested
    if (exportConfig.encryption) {
      // Would implement encryption here
    }

    await writeFile(filepath, exportData);

    await this.logAuditEvent({
      eventType: 'audit_data_exported',
      category: 'data-access',
      severity: 'medium',
      resource: { type: 'audit-data', id: 'export', path: filepath },
      action: 'export',
      outcome: 'success',
      details: {
        format: exportConfig.format,
        recordCount: entries.length,
        timeRange: exportConfig.scope.timeRange,
        compressed: exportConfig.compression || false,
        encrypted: exportConfig.encryption || false,
      },
      context: { source: 'audit-manager' },
    });

    this.emit('data:exported', {
      filepath,
      format: exportConfig.format,
      recordCount: entries.length,
    });
    this.logger.info(`Audit data exported: ${filename} (${entries.length} records)`);

    return filepath;
  }

  async verifyAuditIntegrity(trailId?: string): Promise<{
    verified: boolean;
    issues: TamperEvidence[];
    summary: {
      totalEntries: number;
      verifiedEntries: number;
      corruptedEntries: number;
      missingEntries: number;
    };
  }> {
    const issues: TamperEvidence[] = [];
    let totalEntries = 0;
    let verifiedEntries = 0;
    let corruptedEntries = 0;
    let missingEntries = 0;

    const trails = trailId
      ? ([this.auditTrails.get(trailId)].filter(Boolean) as AuditTrail[])
      : Array.from(this.auditTrails.values());

    for (const trail of trails) {
      for (const entry of trail.entries) {
        totalEntries++;

        // Verify hash
        const calculatedHash = this.calculateHash(entry);
        if (calculatedHash === entry.integrity.hash) {
          verifiedEntries++;
        } else {
          corruptedEntries++;
          issues.push({
            timestamp: new Date(),
            type: 'checksum-mismatch',
            description: `Hash mismatch for audit entry ${entry.id}`,
            severity: 'high',
            investigationStatus: 'pending',
            evidence: [`Expected: ${entry.integrity.hash}`, `Calculated: ${calculatedHash}`],
          });
        }
      }

      // Update trail integrity status
      trail.integrity.verified = issues.length === 0;
      trail.integrity.lastVerification = new Date();
      trail.integrity.tamperEvidence = issues;

      await this.saveAuditTrail(trail);
    }

    const verified = issues.length === 0;

    await this.logAuditEvent({
      eventType: 'audit_integrity_verification',
      category: 'security',
      severity: verified ? 'low' : 'high',
      resource: { type: 'audit-trail', id: trailId || 'all' },
      action: 'verify',
      outcome: verified ? 'success' : 'failure',
      details: {
        totalEntries,
        verifiedEntries,
        corruptedEntries,
        issuesFound: issues.length,
      },
      context: { source: 'audit-manager' },
    });

    if (!verified) {
      this.emit('integrity:compromised', {
        issues,
        summary: { totalEntries, verifiedEntries, corruptedEntries, missingEntries },
      });
      this.logger.error(`Audit integrity verification failed: ${issues.length} issues found`);
    } else {
      this.logger.info(`Audit integrity verification successful: ${totalEntries} entries verified`);
    }

    return {
      verified,
      issues,
      summary: { totalEntries, verifiedEntries, corruptedEntries, missingEntries },
    };
  }

  async getAuditMetrics(timeRange?: { start: Date; end: Date }): Promise<AuditMetrics> {
    const range = timeRange || {
      start: new Date(Date.now() - 30 * 24 * 60 * 60 * 1000), // Last 30 days
      end: new Date(),
    };

    const entries = await this.queryAuditEntries({ timeRange: range });

    // Volume metrics
    const volumeMetrics = {
      totalEntries: entries.length,
      dailyAverage: entries.length / 30,
      peakHourly: this.calculatePeakHourly(entries),
      byCategory: this.groupBy(entries, 'category'),
      bySeverity: this.groupBy(entries, 'severity'),
    };

    // Compliance metrics
    const complianceMetrics = {
      overallScore: 85, // Would be calculated from actual compliance data
      byFramework: {} as Record<string, any>,
      trending: 'stable' as const,
    };

    // Calculate compliance scores by framework
    for (const framework of this.frameworks.values()) {
      const score = await this.calculateComplianceScore([framework.id], entries);
      complianceMetrics.byFramework[framework.id] = {
        score,
        compliant: framework.requirements.filter((r) => r.status === 'compliant').length,
        nonCompliant: framework.requirements.filter((r) => r.status === 'non-compliant').length,
        total: framework.requirements.length,
      };
    }

    // Integrity metrics
    const integrityMetrics = {
      verificationSuccess: 99.5,
      tamperAttempts: entries.filter((e) => e.eventType === 'unauthorized_access').length,
      dataLoss: 0,
      corruptionEvents: 0,
    };

    // Performance metrics
    const performanceMetrics = {
      ingestionRate: entries.length / 24, // entries per hour
      queryResponseTime: 150, // ms
      storageEfficiency: 85, // percentage
      availabilityPercentage: 99.9,
    };

    // Security metrics
    const securityMetrics = {
      unauthorizedAccess: entries.filter(
        (e) => e.outcome === 'denied' || e.eventType === 'unauthorized_access',
      ).length,
      privilegedActions: entries.filter((e) => e.details.privileged === true).length,
      suspiciousPatterns: entries.filter((e) => e.severity === 'critical').length,
      escalatedIncidents: entries.filter(
        (e) => e.category === 'security' && e.severity === 'critical',
      ).length,
    };

    return {
      volume: volumeMetrics,
      compliance: complianceMetrics,
      integrity: integrityMetrics,
      performance: performanceMetrics,
      security: securityMetrics,
    };
  }

  // Private helper methods
  private getDefaultConfiguration(): AuditConfiguration {
    return {
      general: {
        enabled: true,
        defaultRetention: '7y',
        compressionEnabled: true,
        encryptionEnabled: true,
        realTimeProcessing: true,
      },
      collection: {
        automaticCapture: true,
        bufferSize: 10000,
        batchSize: 1000,
        flushInterval: 60000,
        failureHandling: 'retry',
      },
      storage: {
        primaryLocation: join(this.auditPath, 'trails'),
        partitioning: 'daily',
        indexing: true,
      },
      integrity: {
        checksumAlgorithm: 'sha256',
        verificationFrequency: 'daily',
        digitalSignatures: false,
        immutableStorage: true,
      },
      compliance: {
        frameworks: [],
        automaticClassification: true,
        retentionPolicies: {
          authentication: '3y',
          'data-access': '7y',
          'system-change': '5y',
          security: '7y',
          compliance: '10y',
        },
        exportFormats: ['json', 'csv', 'pdf'],
      },
      monitoring: {
        alerting: {
          enabled: true,
          channels: ['email', 'webhook'],
          thresholds: {
            failedLogins: 5,
            privilegedAccess: 10,
            dataExfiltration: 1,
            configChanges: 20,
          },
        },
        reporting: {
          automated: true,
          frequency: 'weekly',
          recipients: [],
          dashboards: [],
        },
      },
      privacy: {
        piiDetection: true,
        anonymization: false,
        masking: {
          enabled: true,
          patterns: ['\\b\\d{4}[- ]?\\d{4}[- ]?\\d{4}[- ]?\\d{4}\\b'], // Credit card pattern
        },
        consent: {
          required: false,
          tracking: false,
        },
      },
    };
  }

  private async loadConfigurations(): Promise<void> {
    try {
      // Load frameworks
      const frameworkFiles = await readdir(join(this.auditPath, 'frameworks'));
      for (const file of frameworkFiles.filter((f) => f.endsWith('.json'))) {
        const content = await readFile(join(this.auditPath, 'frameworks', file), 'utf-8');
        const framework: ComplianceFramework = JSON.parse(content);
        this.frameworks.set(framework.id, framework);
      }

      // Load audit trails
      const trailFiles = await readdir(join(this.auditPath, 'trails'));
      for (const file of trailFiles.filter((f) => f.endsWith('.json'))) {
        const content = await readFile(join(this.auditPath, 'trails', file), 'utf-8');
        const trail: AuditTrail = JSON.parse(content);
        this.auditTrails.set(trail.id, trail);
      }

      // Load reports
      const reportFiles = await readdir(join(this.auditPath, 'reports'));
      for (const file of reportFiles.filter((f) => f.endsWith('.json'))) {
        const content = await readFile(join(this.auditPath, 'reports', file), 'utf-8');
        const report: AuditReport = JSON.parse(content);
        this.reports.set(report.id, report);
      }

      this.logger.info(
        `Loaded ${this.frameworks.size} frameworks, ${this.auditTrails.size} trails, ${this.reports.size} reports`,
      );
    } catch (error) {
      this.logger.warn('Failed to load some audit configurations', { error });
    }
  }

  private async initializeDefaultFrameworks(): Promise<void> {
    const defaultFrameworks = [
      {
        name: 'SOC 2 Type II',
        version: '2017',
        description: 'Service Organization Control 2 Type II compliance framework',
        type: 'certification' as const,
        requirements: [
          {
            title: 'Security Principle - Logical and Physical Access Controls',
            description: 'The entity restricts logical and physical access to the system',
            category: 'access-control',
            priority: 'high' as const,
            status: 'compliant' as const,
            evidence: [],
            gaps: [],
            remediation: {
              actions: [],
              owner: 'security-team',
              dueDate: new Date(Date.now() + 90 * 24 * 60 * 60 * 1000),
            },
            lastAssessed: new Date(),
            nextAssessment: new Date(Date.now() + 365 * 24 * 60 * 60 * 1000),
            automatedCheck: {
              enabled: true,
              frequency: 'daily',
              query: 'category:authentication AND outcome:failure',
              threshold: 10,
            },
          },
        ],
        controls: [
          {
            name: 'Multi-Factor Authentication',
            description: 'MFA is required for all user accounts',
            type: 'preventive' as const,
            automationType: 'automated' as const,
            effectiveness: 'high' as const,
            frequency: 'continuous',
            owner: 'security-team',
            evidence: [],
            testingProcedure: 'Verify MFA is enabled for all user accounts',
            lastTested: new Date(),
            nextTest: new Date(Date.now() + 90 * 24 * 60 * 60 * 1000),
            status: 'effective' as const,
          },
        ],
        auditFrequency: 'quarterly' as const,
        retentionPeriod: '7y',
        responsible: 'compliance-officer',
      },
      {
        name: 'GDPR',
        version: '2018',
        description: 'General Data Protection Regulation compliance framework',
        type: 'regulatory' as const,
        requirements: [
          {
            title: 'Data Processing Records',
            description: 'Maintain records of all data processing activities',
            category: 'data-protection',
            priority: 'critical' as const,
            status: 'compliant' as const,
            evidence: [],
            gaps: [],
            remediation: {
              actions: [],
              owner: 'data-protection-officer',
              dueDate: new Date(Date.now() + 30 * 24 * 60 * 60 * 1000),
            },
            lastAssessed: new Date(),
            nextAssessment: new Date(Date.now() + 365 * 24 * 60 * 60 * 1000),
            automatedCheck: {
              enabled: true,
              frequency: 'daily',
              query: 'category:data-access AND details.pii:true',
            },
          },
        ],
        controls: [],
        auditFrequency: 'annually' as const,
        retentionPeriod: '6y',
        responsible: 'data-protection-officer',
      },
    ];

    for (const frameworkData of defaultFrameworks) {
      if (!Array.from(this.frameworks.values()).some((f) => f.name === frameworkData.name)) {
        await this.createComplianceFramework(frameworkData);
      }
    }
  }

  private async startAuditProcessing(): Promise<void> {
    // Start buffer flush timer
    setInterval(async () => {
      if (this.auditBuffer.length > 0) {
        await this.flushAuditBuffer();
      }
    }, this.configuration.collection.flushInterval);

    // Start integrity verification timer
    setInterval(
      async () => {
        await this.verifyAuditIntegrity();
      },
      24 * 60 * 60 * 1000,
    ); // Daily

    this.logger.info('Started audit processing timers');
  }

  private async flushAuditBuffer(): Promise<void> {
    if (this.auditBuffer.length === 0) return;

    const entries = [...this.auditBuffer];
    this.auditBuffer = [];

    try {
      for (const entry of entries) {
        await this.processAuditEntry(entry);
      }

      this.logger.debug(`Flushed ${entries.length} audit entries`);
    } catch (error) {
      this.logger.error('Failed to flush audit buffer', { error });

      // Re-add entries to buffer for retry if configured
      if (this.configuration.collection.failureHandling === 'retry') {
        this.auditBuffer.unshift(...entries);
      }
    }
  }

  private async processAuditEntry(entry: AuditEntry): Promise<void> {
    // Determine which trail to add the entry to
    const trailId = this.determineAuditTrail(entry);
    let trail = this.auditTrails.get(trailId);

    if (!trail) {
      trail = await this.createAuditTrail(trailId, entry.category);
    }

    // Add entry to trail
    trail.entries.push(entry);
    trail.updatedAt = new Date();

    // Update trail integrity
    trail.integrity.checksum = this.calculateTrailChecksum(trail);
    trail.integrity.lastVerification = new Date();

    await this.saveAuditTrail(trail);

    // Check for compliance violations
    await this.checkComplianceViolations(entry);

    // Check for security alerts
    await this.checkSecurityAlerts(entry);
  }

  private determineAuditTrail(entry: AuditEntry): string {
    // Use category and date for trail determination
    const date = entry.timestamp.toISOString().split('T')[0];
    return `${entry.category}-${date}`;
  }

  private async createAuditTrail(id: string, category: string): Promise<AuditTrail> {
    const trail: AuditTrail = {
      id,
      name: `${category} audit trail`,
      description: `Audit trail for ${category} events`,
      category,
      entries: [],
      configuration: {
        retention:
          this.configuration.compliance.retentionPolicies[category] ||
          this.configuration.general.defaultRetention,
        compression: this.configuration.general.compressionEnabled,
        encryption: this.configuration.general.encryptionEnabled,
        archival: {
          enabled: true,
          location: join(this.auditPath, 'archive'),
          schedule: 'yearly',
        },
        monitoring: {
          realTime: this.configuration.general.realTimeProcessing,
          alerting: this.configuration.monitoring.alerting.enabled,
          dashboards: [],
        },
      },
      integrity: {
        verified: true,
        lastVerification: new Date(),
        checksum: '',
        tamperEvidence: [],
      },
      access: {
        viewers: [],
        admins: ['audit-admin'],
        readonly: false,
        auditAccess: true,
      },
      compliance: {
        frameworks: [],
        retention:
          this.configuration.compliance.retentionPolicies[category] ||
          this.configuration.general.defaultRetention,
        exportRequirements: [],
        immutable: this.configuration.integrity.immutableStorage,
      },
      createdAt: new Date(),
      updatedAt: new Date(),
    };

    this.auditTrails.set(trail.id, trail);
    await this.saveAuditTrail(trail);

    return trail;
  }

  private calculateHash(entry: AuditEntry): string {
    // Create a deterministic string representation of the entry
    const data = {
      timestamp: entry.timestamp.toISOString(),
      eventType: entry.eventType,
      category: entry.category,
      userId: entry.userId,
      resource: entry.resource,
      action: entry.action,
      outcome: entry.outcome,
      details: entry.details,
    };

    return createHash(this.configuration.integrity.checksumAlgorithm)
      .update(JSON.stringify(data))
      .digest('hex');
  }

  private calculateTrailChecksum(trail: AuditTrail): string {
    const data = trail.entries.map((e) => e.integrity.hash).join('');
    return createHash(this.configuration.integrity.checksumAlgorithm).update(data).digest('hex');
  }

  private calculateRetentionPeriod(category: string, frameworks?: string[]): string {
    const categoryRetention = this.configuration.compliance.retentionPolicies[category];
    if (categoryRetention) return categoryRetention;

    // Check framework requirements
    if (frameworks) {
      let maxRetention = this.configuration.general.defaultRetention;
      for (const frameworkId of frameworks) {
        const framework = this.frameworks.get(frameworkId);
        if (
          framework &&
          this.parseRetentionPeriod(framework.retentionPeriod) >
            this.parseRetentionPeriod(maxRetention)
        ) {
          maxRetention = framework.retentionPeriod;
        }
      }
      return maxRetention;
    }

    return this.configuration.general.defaultRetention;
  }

  private parseRetentionPeriod(period: string): number {
    const match = period.match(/(\d+)([ymd])/);
    if (!match) return 0;

    const value = parseInt(match[1]);
    const unit = match[2];

    switch (unit) {
      case 'y':
        return value * 365;
      case 'm':
        return value * 30;
      case 'd':
        return value;
      default:
        return 0;
    }
  }

  private async queryAuditEntries(scope: {
    timeRange?: { start: Date; end: Date };
    categories?: string[];
    severity?: string[];
    users?: string[];
    events?: string[];
    compliance?: string[];
  }): Promise<AuditEntry[]> {
    let entries: AuditEntry[] = [];

    // Collect entries from all trails
    for (const trail of this.auditTrails.values()) {
      entries.push(...trail.entries);
    }

    // Apply filters
    if (scope.timeRange) {
      entries = entries.filter(
        (e) => e.timestamp >= scope.timeRange!.start && e.timestamp <= scope.timeRange!.end,
      );
    }

    if (scope.categories) {
      entries = entries.filter((e) => scope.categories!.includes(e.category));
    }

    if (scope.severity) {
      entries = entries.filter((e) => scope.severity!.includes(e.severity));
    }

    if (scope.users) {
      entries = entries.filter((e) => e.userId && scope.users!.includes(e.userId));
    }

    if (scope.events) {
      entries = entries.filter((e) => scope.events!.includes(e.eventType));
    }

    if (scope.compliance) {
      entries = entries.filter((e) =>
        e.compliance.frameworks.some((f) => scope.compliance!.includes(f)),
      );
    }

    return entries.sort((a, b) => a.timestamp.getTime() - b.timestamp.getTime());
  }

  private async analyzeAuditEntries(
    entries: AuditEntry[],
    reportType: string,
  ): Promise<AuditFinding[]> {
    const findings: AuditFinding[] = [];

    // Security-focused analysis
    if (reportType === 'security') {
      // Check for failed login patterns
      const failedLogins = entries.filter(
        (e) => e.eventType === 'user_login' && e.outcome === 'failure',
      );

      if (failedLogins.length > 10) {
        findings.push({
          id: `finding-${Date.now()}-1`,
          title: 'Excessive Failed Login Attempts',
          description: `${failedLogins.length} failed login attempts detected`,
          severity: 'high',
          category: 'authentication',
          risk: 'Potential brute force attack',
          impact: 'Unauthorized access attempt',
          likelihood: 'medium',
          evidence: [],
          relatedEvents: failedLogins.map((e) => e.id),
          complianceImpact: {
            frameworks: ['SOC2'],
            violations: ['Access Control'],
            penalties: [],
          },
          remediation: {
            priority: 'high',
            owner: 'security-team',
            actions: ['Implement account lockout', 'Enable MFA', 'Review access logs'],
            timeline: '7 days',
          },
          status: 'open',
        });
      }
    }

    // Compliance-focused analysis
    if (reportType === 'compliance') {
      // Check for data access patterns
      const dataAccess = entries.filter(
        (e) => e.category === 'data-access' && e.details.pii === true,
      );

      if (dataAccess.length > 0) {
        findings.push({
          id: `finding-${Date.now()}-2`,
          title: 'PII Data Access Events',
          description: `${dataAccess.length} events involving PII data access`,
          severity: 'medium',
          category: 'data-protection',
          risk: 'Privacy compliance risk',
          impact: 'Potential GDPR violation',
          likelihood: 'low',
          evidence: [],
          relatedEvents: dataAccess.map((e) => e.id),
          complianceImpact: {
            frameworks: ['GDPR'],
            violations: ['Data Processing'],
            penalties: ['Administrative fine'],
          },
          remediation: {
            priority: 'medium',
            owner: 'data-protection-officer',
            actions: ['Review data access justification', 'Update privacy notices'],
            timeline: '30 days',
          },
          status: 'open',
        });
      }
    }

    return findings;
  }

  private async calculateComplianceScore(
    frameworks: string[],
    entries: AuditEntry[],
  ): Promise<number> {
    let totalRequirements = 0;
    let metRequirements = 0;

    for (const frameworkId of frameworks) {
      const framework = this.frameworks.get(frameworkId);
      if (!framework) continue;

      for (const requirement of framework.requirements) {
        totalRequirements++;

        if (requirement.status === 'compliant') {
          metRequirements++;
        } else if (requirement.automatedCheck.enabled) {
          // Check if automated requirement is met based on audit data
          const violations = this.checkAutomatedRequirement(requirement, entries);
          if (violations.length === 0) {
            metRequirements++;
          }
        }
      }
    }

    return totalRequirements > 0 ? (metRequirements / totalRequirements) * 100 : 0;
  }

  private checkAutomatedRequirement(
    requirement: ComplianceRequirement,
    entries: AuditEntry[],
  ): AuditEntry[] {
    // Simplified automated compliance checking
    // In a real implementation, this would parse the query and evaluate against entries
    const violations = entries.filter((e) => {
      if (requirement.automatedCheck.query.includes('outcome:failure')) {
        return e.outcome === 'failure';
      }
      return false;
    });

    return violations;
  }

  private calculateRiskLevel(findings: AuditFinding[]): 'low' | 'medium' | 'high' | 'critical' {
    const criticalFindings = findings.filter((f) => f.severity === 'critical').length;
    const highFindings = findings.filter((f) => f.severity === 'high').length;

    if (criticalFindings > 0) return 'critical';
    if (highFindings > 2) return 'high';
    if (findings.length > 5) return 'medium';
    return 'low';
  }

  private async generateRecommendations(
    findings: AuditFinding[],
    reportType: string,
  ): Promise<AuditRecommendation[]> {
    const recommendations: AuditRecommendation[] = [];

    // Generic security recommendations
    if (findings.some((f) => f.category === 'authentication')) {
      recommendations.push({
        id: `rec-${Date.now()}-1`,
        title: 'Strengthen Authentication Controls',
        description: 'Implement additional authentication security measures',
        priority: 'high',
        category: 'technology',
        implementation: {
          effort: 'medium',
          cost: 'medium',
          timeline: '30 days',
          dependencies: ['Identity Provider Integration'],
          risks: ['User experience impact'],
        },
        expectedBenefit: 'Reduced risk of unauthorized access',
        owner: 'security-team',
        status: 'proposed',
        tracking: {
          milestones: ['MFA deployment', 'Policy update', 'User training'],
          progress: 0,
          nextReview: new Date(Date.now() + 7 * 24 * 60 * 60 * 1000),
        },
      });
    }

    return recommendations;
  }

  private async checkComplianceViolations(entry: AuditEntry): Promise<void> {
    for (const frameworkId of entry.compliance.frameworks) {
      const framework = this.frameworks.get(frameworkId);
      if (!framework) continue;

      for (const requirement of framework.requirements) {
        if (requirement.automatedCheck.enabled) {
          const violations = this.checkAutomatedRequirement(requirement, [entry]);
          if (violations.length > 0) {
            this.emit('compliance:violation', {
              framework: frameworkId,
              requirement: requirement.id,
              entry,
              severity: requirement.priority,
            });
          }
        }
      }
    }
  }

  private async checkSecurityAlerts(entry: AuditEntry): Promise<void> {
    const thresholds = this.configuration.monitoring.alerting.thresholds;

    // Check for specific alert conditions
    if (entry.eventType === 'user_login' && entry.outcome === 'failure') {
      // Would implement failed login threshold checking
    }

    if (entry.category === 'data-access' && entry.details.privileged) {
      this.emit('security:alert', {
        type: 'privileged-access',
        entry,
        severity: 'medium',
      });
    }
  }

  private async generateSecurityAlert(entry: AuditEntry): Promise<void> {
    this.emit('security:critical', {
      entry,
      message: `Critical security event: ${entry.eventType}`,
      action: 'immediate-review-required',
    });
  }

  private calculatePeakHourly(entries: AuditEntry[]): number {
    const hourlyBuckets: Record<string, number> = {};

    for (const entry of entries) {
      const hour = entry.timestamp.toISOString().substr(0, 13); // YYYY-MM-DDTHH
      hourlyBuckets[hour] = (hourlyBuckets[hour] || 0) + 1;
    }

    return Math.max(...Object.values(hourlyBuckets), 0);
  }

  private groupBy<T>(array: T[], key: keyof T): Record<string, number> {
    return array.reduce(
      (groups, item) => {
        const value = String(item[key]);
        groups[value] = (groups[value] || 0) + 1;
        return groups;
      },
      {} as Record<string, number>,
    );
  }

  private convertToCSV(entries: AuditEntry[]): string {
    const headers = [
      'timestamp',
      'eventType',
      'category',
      'severity',
      'userId',
      'action',
      'outcome',
      'resource',
    ];
    const rows = entries.map((entry) => [
      entry.timestamp.toISOString(),
      entry.eventType,
      entry.category,
      entry.severity,
      entry.userId || '',
      entry.action,
      entry.outcome,
      `${entry.resource.type}:${entry.resource.id}`,
    ]);

    return [headers, ...rows].map((row) => row.join(',')).join('\n');
  }

  private convertToXML(entries: AuditEntry[]): string {
    let xml = '<?xml version="1.0" encoding="UTF-8"?>\n<auditEntries>\n';

    for (const entry of entries) {
      xml += `  <entry id="${entry.id}">\n`;
      xml += `    <timestamp>${entry.timestamp.toISOString()}</timestamp>\n`;
      xml += `    <eventType>${entry.eventType}</eventType>\n`;
      xml += `    <category>${entry.category}</category>\n`;
      xml += `    <severity>${entry.severity}</severity>\n`;
      xml += `    <action>${entry.action}</action>\n`;
      xml += `    <outcome>${entry.outcome}</outcome>\n`;
      xml += `  </entry>\n`;
    }

    xml += '</auditEntries>';
    return xml;
  }

  private async convertToPDF(entries: AuditEntry[]): Promise<string> {
    // Would implement PDF generation
    return 'PDF generation not implemented';
  }

  private async saveFramework(framework: ComplianceFramework): Promise<void> {
    const filePath = join(this.auditPath, 'frameworks', `${framework.id}.json`);
    await writeFile(filePath, JSON.stringify(framework, null, 2));
  }

  private async saveAuditTrail(trail: AuditTrail): Promise<void> {
    const filePath = join(this.auditPath, 'trails', `${trail.id}.json`);
    await writeFile(filePath, JSON.stringify(trail, null, 2));