@clduab11/gemini-flow/tests/validation/transaction-integrity-verifier.ts

Revolutionary AI agent swarm coordination platform with Google Services integration, multimedia processing, and production-ready monitoring. Features 8 Google AI services, quantum computing capabilities, and enterprise-grade security.

/**
 * Transaction Integrity Verification System
 * 
 * Provides comprehensive transaction integrity validation for Google Services
 * integration workflows, ensuring ACID properties across distributed operations,
 * handling partial failures, and maintaining data consistency.
 */

import { EventEmitter } from 'events';
import { createHash } from 'crypto';
import { performance } from 'perf_hooks';

export interface TransactionContext {
  transactionId: string;
  sessionId: string;
  initiator: string;
  startTime: Date;
  timeout: number;
  isolation: 'read_uncommitted' | 'read_committed' | 'repeatable_read' | 'serializable';
  operations: TransactionOperation[];
  checkpoints: TransactionCheckpoint[];
  compensations: CompensationAction[];
  state: TransactionState;
  metadata: Record<string, any>;
}

export interface TransactionOperation {
  operationId: string;
  service: string;
  type: 'create' | 'read' | 'update' | 'delete' | 'execute';
  endpoint: string;
  payload: any;
  expectedResult?: any;
  timestamp: Date;
  status: 'pending' | 'executing' | 'completed' | 'failed' | 'compensated';
  duration?: number;
  result?: any;
  error?: Error;
  retryCount: number;
  maxRetries: number;
  idempotencyKey?: string;
}

export interface TransactionCheckpoint {
  checkpointId: string;
  timestamp: Date;
  operationId: string;
  state: any;
  checksum: string;
  canRollback: boolean;
  rollbackData?: any;
}

export interface CompensationAction {
  actionId: string;
  operationId: string;
  service: string;
  action: 'rollback' | 'compensate' | 'retry';
  payload: any;
  status: 'pending' | 'executing' | 'completed' | 'failed';
  timestamp?: Date;
  result?: any;
  error?: Error;
}

export interface TransactionState {
  phase: 'preparing' | 'committing' | 'committed' | 'aborting' | 'aborted' | 'partial';
  completedOperations: number;
  totalOperations: number;
  errorCount: number;
  consistencyLevel: 'strong' | 'eventual' | 'weak' | 'unknown';
  isolationViolations: number;
  integrityScore: number;
}

export interface TransactionReport {
  transactionId: string;
  sessionId: string;
  startTime: Date;
  endTime: Date;
  duration: number;
  finalState: TransactionState;
  operations: TransactionOperation[];
  checkpoints: TransactionCheckpoint[];
  compensations: CompensationAction[];
  integrityVerification: IntegrityVerificationResult;
  recommendations: string[];
}

export interface IntegrityVerificationResult {
  atomicity: {
    score: number;
    violations: AtomicityViolation[];
    passed: boolean;
  };
  consistency: {
    score: number;
    violations: ConsistencyViolation[];
    passed: boolean;
  };
  isolation: {
    score: number;
    violations: IsolationViolation[];
    passed: boolean;
  };
  durability: {
    score: number;
    violations: DurabilityViolation[];
    passed: boolean;
  };
  overall: {
    score: number;
    passed: boolean;
    grade: 'A' | 'B' | 'C' | 'D' | 'F';
  };
}

export interface AtomicityViolation {
  type: 'partial_commit' | 'incomplete_rollback' | 'orphaned_operation';
  operationId: string;
  service: string;
  description: string;
  severity: 'high' | 'medium' | 'low';
  impact: string;
}

export interface ConsistencyViolation {
  type: 'data_inconsistency' | 'constraint_violation' | 'referential_integrity';
  services: string[];
  description: string;
  dataPoints: any[];
  severity: 'high' | 'medium' | 'low';
}

export interface IsolationViolation {
  type: 'dirty_read' | 'non_repeatable_read' | 'phantom_read' | 'lost_update';
  operationIds: string[];
  description: string;
  severity: 'high' | 'medium' | 'low';
}

export interface DurabilityViolation {
  type: 'data_loss' | 'checkpoint_failure' | 'recovery_failure';
  operationId: string;
  description: string;
  severity: 'high' | 'medium' | 'low';
  recoverability: 'recoverable' | 'partial' | 'lost';
}

export class TransactionIntegrityVerifier extends EventEmitter {
  private activeTransactions: Map<string, TransactionContext> = new Map();
  private transactionHistory: Map<string, TransactionReport[]> = new Map();
  private globalState: Map<string, any> = new Map();
  private locks: Map<string, Set<string>> = new Map();
  
  constructor(
    private config: {
      defaultTimeout?: number;
      maxRetries?: number;
      checkpointFrequency?: number;
      isolationLevel?: 'read_uncommitted' | 'read_committed' | 'repeatable_read' | 'serializable';
    } = {}
  ) {
    super();
  }
  
  /**
   * Begin a new distributed transaction
   */
  async beginTransaction(
    sessionId: string,
    initiator: string,
    options: {
      timeout?: number;
      isolation?: 'read_uncommitted' | 'read_committed' | 'repeatable_read' | 'serializable';
      metadata?: Record<string, any>;
    } = {}
  ): Promise<string> {
    const transactionId = this.generateTransactionId();
    
    const context: TransactionContext = {
      transactionId,
      sessionId,
      initiator,
      startTime: new Date(),
      timeout: options.timeout || this.config.defaultTimeout || 300000, // 5 minutes default
      isolation: options.isolation || this.config.isolationLevel || 'read_committed',
      operations: [],
      checkpoints: [],
      compensations: [],
      state: {
        phase: 'preparing',
        completedOperations: 0,
        totalOperations: 0,
        errorCount: 0,
        consistencyLevel: 'strong',
        isolationViolations: 0,
        integrityScore: 1.0
      },
      metadata: options.metadata || {}
    };
    
    this.activeTransactions.set(transactionId, context);
    
    // Set transaction timeout
    setTimeout(() => {
      this.handleTransactionTimeout(transactionId);
    }, context.timeout);
    
    this.emit('transactionBegan', {
      transactionId,
      sessionId,
      initiator,
      isolation: context.isolation
    });
    
    return transactionId;
  }
  
  /**
   * Add an operation to a transaction
   */
  async addOperation(
    transactionId: string,
    operation: Omit<TransactionOperation, 'operationId' | 'timestamp' | 'status' | 'retryCount'>
  ): Promise<string> {
    const context = this.activeTransactions.get(transactionId);
    if (!context) {
      throw new Error(`Transaction ${transactionId} not found`);
    }
    
    if (context.state.phase !== 'preparing') {
      throw new Error(`Cannot add operations to transaction in ${context.state.phase} phase`);
    }
    
    const operationId = this.generateOperationId(transactionId);
    
    const transactionOperation: TransactionOperation = {
      ...operation,
      operationId,
      timestamp: new Date(),
      status: 'pending',
      retryCount: 0,
      maxRetries: this.config.maxRetries || 3
    };
    
    context.operations.push(transactionOperation);
    context.state.totalOperations++;
    
    // Create checkpoint for rollback capability
    if (operation.type !== 'read') {
      await this.createCheckpoint(transactionId, operationId);
    }
    
    this.emit('operationAdded', {
      transactionId,
      operationId,
      service: operation.service,
      type: operation.type
    });
    
    return operationId;
  }
  
  /**
   * Execute a transaction operation with integrity checks
   */
  async executeOperation(
    transactionId: string,
    operationId: string
  ): Promise<any> {
    const context = this.activeTransactions.get(transactionId);
    if (!context) {
      throw new Error(`Transaction ${transactionId} not found`);
    }
    
    const operation = context.operations.find(op => op.operationId === operationId);
    if (!operation) {
      throw new Error(`Operation ${operationId} not found`);
    }
    
    if (operation.status !== 'pending') {
      throw new Error(`Operation ${operationId} is not in pending state`);
    }
    
    // Acquire locks for isolation
    await this.acquireLocks(transactionId, operation);
    
    operation.status = 'executing';
    const startTime = performance.now();
    
    try {
      // Perform pre-execution validation
      await this.validatePreExecution(context, operation);
      
      // Execute the operation
      const result = await this.performOperation(operation);
      
      // Perform post-execution validation
      await this.validatePostExecution(context, operation, result);
      
      operation.result = result;
      operation.status = 'completed';
      operation.duration = performance.now() - startTime;
      
      context.state.completedOperations++;
      
      // Update integrity score
      this.updateIntegrityScore(context);
      
      this.emit('operationCompleted', {
        transactionId,
        operationId,
        duration: operation.duration,
        result
      });
      
      return result;
      
    } catch (error) {
      operation.error = error as Error;
      operation.status = 'failed';
      operation.duration = performance.now() - startTime;
      
      context.state.errorCount++;
      
      this.emit('operationFailed', {
        transactionId,
        operationId,
        error: error as Error,
        retryCount: operation.retryCount
      });
      
      // Attempt retry if allowed
      if (operation.retryCount < operation.maxRetries) {
        return this.retryOperation(transactionId, operationId);
      }
      
      // Create compensation action
      await this.createCompensationAction(transactionId, operationId, error as Error);
      
      throw error;
      
    } finally {
      // Release locks
      this.releaseLocks(transactionId, operation);
    }
  }
  
  /**
   * Commit the transaction
   */
  async commitTransaction(transactionId: string): Promise<TransactionReport> {
    const context = this.activeTransactions.get(transactionId);
    if (!context) {
      throw new Error(`Transaction ${transactionId} not found`);
    }
    
    context.state.phase = 'committing';
    
    try {
      // Validate all operations completed successfully
      const failedOps = context.operations.filter(op => op.status === 'failed');
      if (failedOps.length > 0) {
        throw new Error(`Cannot commit transaction with ${failedOps.length} failed operations`);
      }
      
      // Perform final integrity verification
      const integrityResult = await this.verifyTransactionIntegrity(context);
      
      if (!integrityResult.overall.passed) {
        throw new Error(`Transaction integrity verification failed: ${integrityResult.overall.score}`);
      }
      
      // Commit all operations
      await this.performCommit(context);
      
      context.state.phase = 'committed';
      
      const report = await this.generateTransactionReport(context, integrityResult);
      
      // Store in history
      const history = this.transactionHistory.get(context.sessionId) || [];
      history.push(report);
      this.transactionHistory.set(context.sessionId, history);
      
      // Cleanup
      this.activeTransactions.delete(transactionId);
      
      this.emit('transactionCommitted', {
        transactionId,
        sessionId: context.sessionId,
        duration: report.duration,
        integrityScore: integrityResult.overall.score
      });
      
      return report;
      
    } catch (error) {
      // Rollback on commit failure
      await this.rollbackTransaction(transactionId, error as Error);
      throw error;
    }
  }
  
  /**
   * Rollback the transaction
   */
  async rollbackTransaction(transactionId: string, reason?: Error): Promise<void> {
    const context = this.activeTransactions.get(transactionId);
    if (!context) {
      throw new Error(`Transaction ${transactionId} not found`);
    }
    
    context.state.phase = 'aborting';
    
    try {
      // Execute compensations in reverse order
      const completedOps = context.operations
        .filter(op => op.status === 'completed')
        .reverse();
      
      for (const operation of completedOps) {
        await this.compensateOperation(context, operation);
      }
      
      // Restore from checkpoints
      await this.restoreFromCheckpoints(context);
      
      context.state.phase = 'aborted';
      
      this.emit('transactionRolledBack', {
        transactionId,
        sessionId: context.sessionId,
        reason: reason?.message,
        compensationsExecuted: context.compensations.length
      });
      
    } catch (rollbackError) {
      context.state.phase = 'partial';
      
      this.emit('rollbackFailed', {
        transactionId,
        originalError: reason,
        rollbackError
      });
      
      throw rollbackError;
    } finally {
      this.activeTransactions.delete(transactionId);
    }
  }
  
  /**
   * Verify transaction integrity (ACID properties)
   */
  async verifyTransactionIntegrity(context: TransactionContext): Promise<IntegrityVerificationResult> {
    const atomicity = await this.verifyAtomicity(context);
    const consistency = await this.verifyConsistency(context);
    const isolation = await this.verifyIsolation(context);
    const durability = await this.verifyDurability(context);
    
    const overallScore = (atomicity.score + consistency.score + isolation.score + durability.score) / 4;
    const overallPassed = atomicity.passed && consistency.passed && isolation.passed && durability.passed;
    
    let grade: 'A' | 'B' | 'C' | 'D' | 'F';
    if (overallScore >= 0.9) grade = 'A';
    else if (overallScore >= 0.8) grade = 'B';
    else if (overallScore >= 0.7) grade = 'C';
    else if (overallScore >= 0.6) grade = 'D';
    else grade = 'F';
    
    return {
      atomicity,
      consistency,
      isolation,
      durability,
      overall: {
        score: overallScore,
        passed: overallPassed,
        grade
      }
    };
  }
  
  // Private helper methods
  
  private async verifyAtomicity(context: TransactionContext): Promise<{score: number, violations: AtomicityViolation[], passed: boolean}> {
    const violations: AtomicityViolation[] = [];
    
    // Check for partial commits
    const completedOps = context.operations.filter(op => op.status === 'completed').length;
    const failedOps = context.operations.filter(op => op.status === 'failed').length;
    
    if (completedOps > 0 && failedOps > 0 && context.state.phase !== 'aborting') {
      violations.push({
        type: 'partial_commit',
        operationId: 'multiple',
        service: 'multiple',
        description: `Transaction has both completed (${completedOps}) and failed (${failedOps}) operations`,
        severity: 'high',
        impact: 'Data inconsistency across services'
      });
    }
    
    // Check for incomplete rollbacks
    const uncompensdatedOps = context.operations.filter(op => 
      op.status === 'completed' && 
      !context.compensations.some(comp => comp.operationId === op.operationId && comp.status === 'completed')
    );
    
    if (context.state.phase === 'aborted' && uncompensdatedOps.length > 0) {
      violations.push({
        type: 'incomplete_rollback',
        operationId: uncompensdatedOps[0].operationId,
        service: uncompensdatedOps[0].service,
        description: `${uncompensdatedOps.length} operations not compensated during rollback`,
        severity: 'high',
        impact: 'Partial data remains committed'
      });
    }
    
    // Check for orphaned operations
    context.operations.forEach(op => {
      if (op.status === 'executing' && Date.now() - op.timestamp.getTime() > 60000) {
        violations.push({
          type: 'orphaned_operation',
          operationId: op.operationId,
          service: op.service,
          description: 'Operation has been executing for over 60 seconds',
          severity: 'medium',
          impact: 'Resource leakage and inconsistent state'
        });
      }
    });
    
    const score = Math.max(0, 1 - (violations.length * 0.2));
    return {
      score,
      violations,
      passed: violations.filter(v => v.severity === 'high').length === 0
    };
  }
  
  private async verifyConsistency(context: TransactionContext): Promise<{score: number, violations: ConsistencyViolation[], passed: boolean}> {
    const violations: ConsistencyViolation[] = [];
    
    // Group operations by data entity
    const entityGroups = new Map<string, TransactionOperation[]>();
    
    context.operations.forEach(op => {
      const entityKey = this.extractEntityKey(op);
      if (!entityGroups.has(entityKey)) {
        entityGroups.set(entityKey, []);
      }
      entityGroups.get(entityKey)!.push(op);
    });
    
    // Check consistency within each entity group
    for (const [entityKey, operations] of entityGroups) {
      const dataStates = operations
        .filter(op => op.result && op.status === 'completed')
        .map(op => ({ service: op.service, data: op.result }));
      
      if (dataStates.length > 1) {
        const inconsistencies = this.detectDataInconsistencies(dataStates);
        
        if (inconsistencies.length > 0) {
          violations.push({
            type: 'data_inconsistency',
            services: [...new Set(dataStates.map(ds => ds.service))],
            description: `Inconsistent data states detected for entity ${entityKey}`,
            dataPoints: inconsistencies,
            severity: 'high'
          });
        }
      }
    }
    
    const score = Math.max(0, 1 - (violations.length * 0.3));
    return {
      score,
      violations,
      passed: violations.filter(v => v.severity === 'high').length === 0
    };
  }
  
  private async verifyIsolation(context: TransactionContext): Promise<{score: number, violations: IsolationViolation[], passed: boolean}> {
    const violations: IsolationViolation[] = [];
    
    // This would typically check for isolation violations across concurrent transactions
    // For now, we'll check for potential issues within the transaction
    
    const score = Math.max(0, 1 - (context.state.isolationViolations * 0.1));
    return {
      score,
      violations,
      passed: context.state.isolationViolations === 0
    };
  }
  
  private async verifyDurability(context: TransactionContext): Promise<{score: number, violations: DurabilityViolation[], passed: boolean}> {
    const violations: DurabilityViolation[] = [];
    
    // Check checkpoint integrity
    const checkpointFailures = context.checkpoints.filter(cp => !cp.canRollback);
    
    checkpointFailures.forEach(cp => {
      violations.push({
        type: 'checkpoint_failure',
        operationId: cp.operationId,
        description: `Checkpoint ${cp.checkpointId} cannot be used for rollback`,
        severity: 'medium',
        recoverability: 'partial'
      });
    });
    
    const score = Math.max(0, 1 - (violations.length * 0.15));
    return {
      score,
      violations,
      passed: violations.filter(v => v.severity === 'high').length === 0
    };
  }
  
  private generateTransactionId(): string {
    return `txn-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`;
  }
  
  private generateOperationId(transactionId: string): string {
    const context = this.activeTransactions.get(transactionId);
    const opCount = context ? context.operations.length : 0;
    return `${transactionId}-op-${opCount + 1}`;
  }
  
  private async createCheckpoint(transactionId: string, operationId: string): Promise<void> {
    const context = this.activeTransactions.get(transactionId);
    if (!context) return;
    
    const checkpointId = `${operationId}-checkpoint-${Date.now()}`;
    const state = this.captureCurrentState(operationId);
    
    const checkpoint: TransactionCheckpoint = {
      checkpointId,
      timestamp: new Date(),
      operationId,
      state,
      checksum: this.calculateStateChecksum(state),
      canRollback: true,
      rollbackData: this.captureRollbackData(operationId)
    };
    
    context.checkpoints.push(checkpoint);
  }
  
  private async performOperation(operation: TransactionOperation): Promise<any> {
    // This would typically make HTTP requests to actual services
    // For testing purposes, we'll simulate the operation
    
    await new Promise(resolve => setTimeout(resolve, 100 + Math.random() * 200));
    
    // Simulate occasional failures for testing
    if (Math.random() < 0.05) { // 5% failure rate
      throw new Error(`Simulated failure for operation ${operation.operationId}`);
    }
    
    return {
      operationId: operation.operationId,
      service: operation.service,
      timestamp: new Date(),
      result: 'success',
      data: operation.payload
    };
  }
  
  private async retryOperation(transactionId: string, operationId: string): Promise<any> {
    const context = this.activeTransactions.get(transactionId);
    if (!context) throw new Error(`Transaction ${transactionId} not found`);
    
    const operation = context.operations.find(op => op.operationId === operationId);
    if (!operation) throw new Error(`Operation ${operationId} not found`);
    
    operation.retryCount++;
    operation.status = 'pending';
    
    // Exponential backoff
    const delay = Math.min(1000 * Math.pow(2, operation.retryCount - 1), 30000);
    await new Promise(resolve => setTimeout(resolve, delay));
    
    return this.executeOperation(transactionId, operationId);
  }
  
  private async createCompensationAction(
    transactionId: string,
    operationId: string,
    error: Error
  ): Promise<void> {
    const context = this.activeTransactions.get(transactionId);
    if (!context) return;
    
    const operation = context.operations.find(op => op.operationId === operationId);
    if (!operation) return;
    
    const compensation: CompensationAction = {
      actionId: `${operationId}-compensation`,
      operationId,
      service: operation.service,
      action: 'rollback',
      payload: this.generateCompensationPayload(operation),
      status: 'pending'
    };
    
    context.compensations.push(compensation);
  }
  
  private generateCompensationPayload(operation: TransactionOperation): any {
    // Generate appropriate compensation payload based on operation type
    switch (operation.type) {
      case 'create':
        return { action: 'delete', id: operation.result?.id };
      case 'update':
        return { action: 'restore', previousState: operation.result?.previousState };
      case 'delete':
        return { action: 'restore', data: operation.result?.deletedData };
      default:
        return { action: 'noop' };
    }
  }
  
  private async handleTransactionTimeout(transactionId: string): Promise<void> {
    const context = this.activeTransactions.get(transactionId);
    if (!context) return;
    
    if (context.state.phase === 'preparing' || context.state.phase === 'committing') {
      this.emit('transactionTimeout', { transactionId, phase: context.state.phase });
      await this.rollbackTransaction(transactionId, new Error('Transaction timeout'));
    }
  }
  
  private extractEntityKey(operation: TransactionOperation): string {
    // Extract entity key from operation for consistency checking
    return operation.payload?.entityId || operation.payload?.id || 'unknown';
  }
  
  private detectDataInconsistencies(dataStates: Array<{service: string, data: any}>): any[] {
    const inconsistencies: any[] = [];
    
    // Simple consistency check - compare common fields
    const commonFields = ['id', 'status', 'timestamp', 'version'];
    
    commonFields.forEach(field => {
      const values = dataStates
        .filter(ds => ds.data[field] !== undefined)
        .map(ds => ({ service: ds.service, value: ds.data[field] }));
      
      const uniqueValues = new Set(values.map(v => v.value));
      
      if (uniqueValues.size > 1) {
        inconsistencies.push({
          field,
          values,
          description: `Field '${field}' has different values across services`
        });
      }
    });
    
    return inconsistencies;
  }
  
  private updateIntegrityScore(context: TransactionContext): void {
    const totalOps = context.state.totalOperations;
    const completedOps = context.state.completedOperations;
    const errorCount = context.state.errorCount;
    
    if (totalOps === 0) {
      context.state.integrityScore = 1.0;
      return;
    }
    
    const completionRate = completedOps / totalOps;
    const errorRate = errorCount / totalOps;
    const isolationPenalty = context.state.isolationViolations * 0.1;
    
    context.state.integrityScore = Math.max(0, completionRate - errorRate - isolationPenalty);
  }
  
  private async acquireLocks(transactionId: string, operation: TransactionOperation): Promise<void> {
    // Simple lock mechanism for demonstration
    const resourceKey = `${operation.service}:${this.extractEntityKey(operation)}`;
    
    if (!this.locks.has(resourceKey)) {
      this.locks.set(resourceKey, new Set());
    }
    
    this.locks.get(resourceKey)!.add(transactionId);
  }
  
  private releaseLocks(transactionId: string, operation: TransactionOperation): void {
    const resourceKey = `${operation.service}:${this.extractEntityKey(operation)}`;
    
    if (this.locks.has(resourceKey)) {
      this.locks.get(resourceKey)!.delete(transactionId);
      
      if (this.locks.get(resourceKey)!.size === 0) {
        this.locks.delete(resourceKey);
      }
    }
  }
  
  private async validatePreExecution(context: TransactionContext, operation: TransactionOperation): Promise<void> {
    // Pre-execution validation logic
    if (operation.idempotencyKey) {
      // Check if operation with same idempotency key already executed
      const existingOp = context.operations.find(
        op => op.idempotencyKey === operation.idempotencyKey && op.status === 'completed'
      );
      
      if (existingOp) {
        throw new Error(`Operation with idempotency key ${operation.idempotencyKey} already executed`);
      }
    }
  }
  
  private async validatePostExecution(
    context: TransactionContext,
    operation: TransactionOperation,
    result: any
  ): Promise<void> {
    // Post-execution validation logic
    if (operation.expectedResult) {
      const isExpectedResult = this.compareResults(result, operation.expectedResult);
      if (!isExpectedResult) {
        throw new Error(`Operation result does not match expected result`);
      }
    }
  }
  
  private compareResults(actual: any, expected: any): boolean {
    // Simple result comparison - can be enhanced for complex objects
    return JSON.stringify(actual) === JSON.stringify(expected);
  }
  
  private captureCurrentState(operationId: string): any {
    // Capture current state for checkpoint
    return {
      operationId,
      timestamp: new Date(),
      globalState: Object.fromEntries(this.globalState)
    };
  }
  
  private calculateStateChecksum(state: any): string {
    const serialized = JSON.stringify(state, Object.keys(state).sort());
    return createHash('sha256').update(serialized).digest('hex').substr(0, 16);
  }
  
  private captureRollbackData(operationId: string): any {
    // Capture data needed for rollback
    return {
      operationId,
      rollbackInstructions: [],
      stateSnapshot: this.captureCurrentState(operationId)
    };
  }
  
  private async performCommit(context: TransactionContext): Promise<void> {
    // Perform actual commit operations
    for (const operation of context.operations) {
      if (operation.status === 'completed') {
        // Mark as permanently committed
        operation.result = { ...operation.result, committed: true };
      }
    }
  }
  
  private async compensateOperation(context: TransactionContext, operation: TransactionOperation): Promise<void> {
    const compensation = context.compensations.find(comp => comp.operationId === operation.operationId);
    if (!compensation) return;
    
    compensation.status = 'executing';
    compensation.timestamp = new Date();
    
    try {
      // Execute compensation
      const result = await this.performCompensation(compensation);
      
      compensation.result = result;
      compensation.status = 'completed';
      
      // Mark original operation as compensated
      operation.status = 'compensated';
      
    } catch (error) {
      compensation.error = error as Error;
      compensation.status = 'failed';
      throw error;
    }
  }
  
  private async performCompensation(compensation: CompensationAction): Promise<any> {
    // Simulate compensation operation
    await new Promise(resolve => setTimeout(resolve, 50 + Math.random() * 100));
    
    return {
      compensationId: compensation.actionId,
      action: compensation.action,
      timestamp: new Date(),
      result: 'compensated'
    };
  }
  
  private async restoreFromCheckpoints(context: TransactionContext): Promise<void> {
    // Restore state from checkpoints
    for (const checkpoint of context.checkpoints.reverse()) {
      if (checkpoint.canRollback && checkpoint.rollbackData) {
        // Restore state from checkpoint
        this.restoreState(checkpoint.rollbackData);
      }
    }
  }
  
  private restoreState(rollbackData: any): void {
    // Restore global state from rollback data
    if (rollbackData.stateSnapshot?.globalState) {
      this.globalState.clear();
      Object.entries(rollbackData.stateSnapshot.globalState).forEach(([key, value]) => {
        this.globalState.set(key, value);
      });
    }
  }
  
  private async generateTransactionReport(
    context: TransactionContext,
    integrityResult: IntegrityVerificationResult
  ): Promise<TransactionReport> {
    const endTime = new Date();
    const duration = endTime.getTime() - context.startTime.getTime();
    
    const recommendations: string[] = [];
    
    // Generate recommendations based on integrity results
    if (!integrityResult.atomicity.passed) {
      recommendations.push('Implement better error handling and rollback mechanisms');
    }
    
    if (!integrityResult.consistency.passed) {
      recommendations.push('Add data validation and consistency checks across services');
    }
    
    if (!integrityResult.isolation.passed) {
      recommendations.push('Implement proper locking and isolation mechanisms');
    }
    
    if (!integrityResult.durability.passed) {
      recommendations.push('Improve checkpoint and recovery mechanisms');
    }
    
    return {
      transactionId: context.transactionId,
      sessionId: context.sessionId,
      startTime: context.startTime,
      endTime,
      duration,
      finalState: context.state,
      operations: [...context.operations],
      checkpoints: [...context.checkpoints],
      compensations: [...context.compensations],
      integrityVerification: integrityResult,
      recommendations
    };
  }
  
  /**
   * Get transaction history for a session
   */
  getTransactionHistory(sessionId: string): TransactionReport[] {
    return this.transactionHistory.get(sessionId) || [];
  }
  
  /**
   * Get active transaction context
   */
  getActiveTransaction(transactionId: string): TransactionContext | undefined {
    return this.activeTransactions.get(transactionId);
  }
  
  /**
   * Get all active transactions
   */
  getActiveTransactions(): TransactionContext[] {
    return Array.from(this.activeTransactions.values());
  }
}

export default TransactionIntegrityVerifier;