Transaction Lifecycle Optimization

// Transaction timing profiler
class TransactionProfiler {
  async profileTransaction(transaction) {
    const timeline = {};
    
    // Stage 1: Submission timing
    timeline.submissionStart = Date.now();
    const result = await this.client.submit(transaction);
    timeline.submissionEnd = Date.now();
    timeline.submissionLatency = timeline.submissionEnd - timeline.submissionStart;
    
    // Stage 3: Propagation monitoring
    timeline.propagationStart = timeline.submissionEnd;
    const propagationMetrics = await this.monitorPropagation(transaction.hash);
    timeline.propagationEnd = propagationMetrics.lastValidatorReceived;
    timeline.propagationLatency = timeline.propagationEnd - timeline.propagationStart;
    
    // Stage 5: Consensus completion
    timeline.consensusStart = await this.getNextLedgerCloseTime();
    const finalResult = await this.waitForValidation(transaction.hash);
    timeline.consensusEnd = finalResult.ledgerCloseTime;
    timeline.totalLatency = timeline.consensusEnd - timeline.submissionStart;
    
    return timeline;
  }
}

class DynamicFeeEstimator {
  async estimateOptimalFee(urgency = 'normal') {
    const mempoolAnalysis = await this.analyzeMempoolState();
    
    const baseFee = 12; // drops
    let multiplier = 1;
    
    // Adjust based on mempool congestion
    if (mempoolAnalysis.pendingTransactions > 1000) {
      multiplier *= 2;
    }
    if (mempoolAnalysis.pendingTransactions > 5000) {
      multiplier *= 3;
    }
    
    // Adjust based on urgency
    switch (urgency) {
      case 'low': multiplier *= 0.8; break;
      case 'normal': break;
      case 'high': multiplier *= 2; break;
      case 'critical': multiplier *= 5; break;
    }
    
    // Cap at reasonable maximum
    const recommendedFee = Math.min(baseFee * multiplier, 1000);
    
    return {
      fee: recommendedFee,
      confidence: this.calculateConfidence(mempoolAnalysis),
      estimatedInclusionTime: this.estimateInclusionTime(recommendedFee, mempoolAnalysis)
    };
  }
}

class SequenceManager {
  async allocateSequenceRange(account, count) {
    const currentSequence = await this.getCurrentSequence(account);
    const allocated = {
      start: currentSequence + 1,
      end: currentSequence + count,
      account: account
    };
    
    // Reserve these numbers locally
    this.reservedSequences.set(account, allocated);
    return allocated;
  }
  
  async buildBatch(account, transactions) {
    const allocation = await this.allocateSequenceRange(account, transactions.length);
    
    return transactions.map((tx, index) => ({
      ...tx,
      Account: account,
      Sequence: allocation.start + index
    }));
  }
}

class ResilientBatchProcessor {
  async processBatch(transactions) {
    const results = [];
    
    // Submit all transactions simultaneously
    const submissions = await Promise.allSettled(
      transactions.map(tx => this.submitTransaction(tx))
    );
    
    // Identify failures and create recovery batch
    const failures = [];
    submissions.forEach((result, index) => {
      if (result.status === 'rejected') {
        failures.push({
          original: transactions[index],
          error: result.reason,
          retryStrategy: this.determineRetryStrategy(result.reason)
        });
      }
    });
    
    // Process recovery batch with adjusted parameters
    if (failures.length > 0) {
      const recoveryBatch = await this.buildRecoveryBatch(failures);
      const recoveryResults = await this.processBatch(recoveryBatch);
      results.push(...recoveryResults);
    }
    
    return results;
  }
}

class DependencyAnalyzer {
  analyzeBatchDependencies(transactions) {
    const dependencyGraph = new Map();
    
    transactions.forEach((tx, index) => {
      const dependencies = [];
      
      // Check for account sequence dependencies
      for (let i = 0; i < index; i++) {
        if (transactions[i].Account === tx.Account) {
          dependencies.push(i);
        }
      }
      
      // Check for destination tag dependencies
      if (tx.DestinationTag) {
        for (let i = 0; i < index; i++) {
          if (this.sharesDestination(transactions[i], tx)) {
            dependencies.push(i);
          }
        }
      }
      
      dependencyGraph.set(index, dependencies);
    });
    
    return this.identifyParallelGroups(dependencyGraph);
  }
}

class StagedBatchProcessor {
  async processComplexBatch(transactions) {
    const stages = this.dependencyAnalyzer.identifyStages(transactions);
    const results = [];
    
    for (const stage of stages) {
      // Submit all transactions in this stage simultaneously
      const stageTransactions = stage.map(index => transactions[index]);
      const stagePromises = stageTransactions.map(tx => this.submitAndWaitForValidation(tx));
      
      // Wait for all transactions in this stage to complete
      const stageResults = await Promise.allSettled(stagePromises);
      
      // Check for failures that might affect subsequent stages
      const failures = stageResults.filter(r => r.status === 'rejected');
      if (failures.length > 0) {
        return this.handleStageFailure(failures, stages, results);
      }
      
      results.push(...stageResults);
    }
    
    return results;
  }
}

class ValidatorAnalyzer {
  async analyzeValidatorPerformance() {
    const validators = await this.getActiveValidators();
    const analysis = new Map();
    
    for (const validator of validators) {
      const metrics = await this.measureValidatorMetrics(validator);
      
      analysis.set(validator.publicKey, {
        location: await this.geolocateValidator(validator),
        avgLatency: metrics.latency.average,
        reliability: metrics.uptime,
        processingSpeed: metrics.avgProcessingTime,
        connectivity: await this.analyzeConnectivity(validator),
        influence: await this.calculateInfluence(validator)
      });
    }
    
    return this.rankValidators(analysis);
  }
  
  calculateOptimalSubmissionStrategy(validatorAnalysis) {
    // Identify validators with best propagation characteristics
    const topValidators = Array.from(validatorAnalysis.entries())
      .sort((a, b) => this.calculatePropagationScore(b[1]) - this.calculatePropagationScore(a[1]))
      .slice(0, 10);
    
    // Find servers with best connectivity to top validators
    const optimalServers = this.findOptimalServers(topValidators);
    
    return {
      primaryServers: optimalServers.slice(0, 3),
      fallbackServers: optimalServers.slice(3, 6),
      expectedPropagationTime: this.estimatePropagationTime(optimalServers, topValidators)
    };
  }
}

class RedundantSubmissionManager {
  async submitWithRedundancy(transaction, redundancyLevel = 3) {
    const servers = this.selectOptimalServers(redundancyLevel);
    const submissions = [];
    
    // Submit to multiple servers simultaneously
    for (const server of servers) {
      submissions.push(this.submitToServer(transaction, server));
    }
    
    // Return as soon as first submission succeeds
    const result = await Promise.race(submissions);
    
    // Cancel remaining submissions to avoid duplicates
    submissions.forEach(p => p.cancel?.());
    
    return result;
  }
  
  selectOptimalServers(count) {
    return this.servers
      .filter(s => s.isHealthy && s.avgLatency < 100)
      .sort((a, b) => this.calculateServerScore(b) - this.calculateServerScore(a))
      .slice(0, count);
  }
}

class LoadBalancedSubmitter {
  constructor() {
    this.serverLoads = new Map();
    this.performanceHistory = new Map();
  }
  
  async submitTransaction(transaction) {
    const server = this.selectLeastLoadedServer();
    
    try {
      this.serverLoads.set(server, (this.serverLoads.get(server) || 0) + 1);
      const result = await this.submitToServer(transaction, server);
      this.recordSuccess(server);
      return result;
    } catch (error) {
      this.recordFailure(server, error);
      // Retry with different server
      return this.submitTransaction(transaction);
    } finally {
      this.serverLoads.set(server, Math.max(0, (this.serverLoads.get(server) || 0) - 1));
    }
  }
}

class BatchSignatureVerifier {
  constructor() {
    this.pendingVerifications = [];
    this.batchSize = 100;
    this.batchTimeout = 10; // ms
  }
  
  async verifySignature(transaction) {
    return new Promise((resolve, reject) => {
      this.pendingVerifications.push({
        transaction,
        resolve,
        reject,
        timestamp: Date.now()
      });
      
      if (this.pendingVerifications.length >= this.batchSize) {
        this.processBatch();
      } else if (this.pendingVerifications.length === 1) {
        // Start timeout for partial batch
        setTimeout(() => this.processBatch(), this.batchTimeout);
      }
    });
  }
  
  async processBatch() {
    const batch = this.pendingVerifications.splice(0, this.batchSize);
    if (batch.length === 0) return;
    
    try {
      // Use native batch verification if available
      const results = await this.cryptoLib.batchVerifySignatures(
        batch.map(item => ({
          message: item.transaction.signingData,
          signature: item.transaction.TxnSignature,
          publicKey: item.transaction.SigningPubKey
        }))
      );
      
      // Resolve individual promises
      batch.forEach((item, index) => {
        if (results[index]) {
          item.resolve(true);
        } else {
          item.reject(new Error('Invalid signature'));
        }
      });
    } catch (error) {
      // Fall back to individual verification
      batch.forEach(item => this.verifyIndividually(item));
    }
  }
}

class OptimizedMerkleTree {
  updateLeaf(leafIndex, newValue) {
    // Mark path to root as dirty
    let currentIndex = leafIndex;
    const dirtyPath = [];
    
    while (currentIndex > 0) {
      dirtyPath.push(currentIndex);
      currentIndex = Math.floor((currentIndex - 1) / 2);
    }
    
    // Update leaf value
    this.leaves[leafIndex] = newValue;
    
    // Recalculate only dirty nodes
    for (const index of dirtyPath.reverse()) {
      this.recalculateNode(index);
    }
  }
  
  batchUpdate(updates) {
    // Collect all dirty paths
    const dirtyNodes = new Set();
    
    for (const {leafIndex, newValue} of updates) {
      this.leaves[leafIndex] = newValue;
      
      let currentIndex = leafIndex;
      while (currentIndex > 0) {
        dirtyNodes.add(currentIndex);
        currentIndex = Math.floor((currentIndex - 1) / 2);
      }
    }
    
    // Recalculate dirty nodes in bottom-up order
    const sortedDirtyNodes = Array.from(dirtyNodes).sort((a, b) => b - a);
    for (const index of sortedDirtyNodes) {
      this.recalculateNode(index);
    }
  }
}

class StateUpdateBatcher {
  constructor() {
    this.pendingUpdates = new Map();
    this.batchTimeout = 5; // ms
    this.maxBatchSize = 1000;
  }
  
  async updateState(key, value) {
    this.pendingUpdates.set(key, value);
    
    if (this.pendingUpdates.size >= this.maxBatchSize) {
      await this.flushBatch();
    } else if (this.pendingUpdates.size === 1) {
      setTimeout(() => this.flushBatch(), this.batchTimeout);
    }
  }
  
  async flushBatch() {
    if (this.pendingUpdates.size === 0) return;
    
    const updates = new Map(this.pendingUpdates);
    this.pendingUpdates.clear();
    
    // Execute all updates in single database transaction
    await this.database.transaction(async (tx) => {
      for (const [key, value] of updates) {
        await tx.set(key, value);
      }
    });
  }
}