dbis_core/src/infrastructure/quantum/proxy/quantum-translation.service.ts

// Quantum Translation Service
// FX & risk translation for legacy protocols

import prisma from '@/shared/database/prisma';
import { Decimal } from '@prisma/client/runtime/library';
import { v4 as uuidv4 } from 'uuid';
import { logger } from '@/infrastructure/monitoring/logger';


export interface QuantumTranslationRequest {
  legacyProtocol: 'SWIFT' | 'ISO20022' | 'ACH' | 'SEPA' | 'PRIVATE_BANK';
  transactionData: any;
  amount: string;
  currencyCode: string;
}

export interface QuantumTranslationResult {
  translationId: string;
  fxRate: Decimal;
  riskScore: Decimal;
  quantumCompatibleAmount: Decimal;
  quantumCompatibleCurrency: string;
  protocolMapping: any;
}

export class QuantumTranslationService {
  /**
   * Translate legacy transaction to quantum-compatible format
   * Handles FX conversion and risk assessment
   */
  async translateLegacyTransaction(
    request: QuantumTranslationRequest
  ): Promise<QuantumTranslationResult> {
    logger.info('QPS: Translating legacy transaction', {
      legacyProtocol: request.legacyProtocol,
    });

    const translationId = `QPS-TRANS-${uuidv4()}`;

    // Step 1: Get protocol mapping
    const protocolMapping = await this.getProtocolMapping(request.legacyProtocol);

    // Step 2: Translate FX
    const fxTranslation = await this.translateFx({
      amount: request.amount,
      currencyCode: request.currencyCode,
      legacyProtocol: request.legacyProtocol,
    });

    // Step 3: Translate risk
    const riskTranslation = await this.translateRisk({
      transactionData: request.transactionData,
      legacyProtocol: request.legacyProtocol,
    });

    // Step 4: Create quantum-compatible format
    const quantumCompatibleAmount = fxTranslation.quantumAmount;
    const quantumCompatibleCurrency = fxTranslation.quantumCurrency;

    // Step 5: Save translation record
    const translation = await prisma.quantum_translations.create({
      data: {
        id: uuidv4(),
        translationId,
        legacyProtocol: request.legacyProtocol,
        legacyAmount: new Decimal(request.amount),
        legacyCurrency: request.currencyCode,
        quantumAmount: quantumCompatibleAmount,
        quantumCurrency: quantumCompatibleCurrency,
        fxRate: fxTranslation.fxRate,
        riskScore: riskTranslation.riskScore,
        protocolMapping: protocolMapping as any,
        transactionData: request.transactionData as any,
        status: 'completed',
        createdAt: new Date(),
        updatedAt: new Date(),
      },
    });

    logger.info('QPS: Translation completed', {
      translationId,
      quantumAmount: quantumCompatibleAmount.toString(),
    });

    return {
      translationId,
      fxRate: fxTranslation.fxRate,
      riskScore: riskTranslation.riskScore,
      quantumCompatibleAmount,
      quantumCompatibleCurrency,
      protocolMapping,
    };
  }

  /**
   * Get protocol mapping for legacy protocol
   */
  private async getProtocolMapping(
    legacyProtocol: string
  ): Promise<any> {
    const mapping = await prisma.legacy_protocol_mappings.findFirst({
      where: { legacyProtocol, status: 'active' },
    });

    if (mapping) {
      return mapping.mappingConfig;
    }

    // Default mappings
    const defaultMappings: Record<string, any> = {
      SWIFT: {
        messageType: 'MT103',
        quantumFormat: 'ISO20022',
        fieldMapping: {
          sender: 'sourceBankId',
          receiver: 'destinationBankId',
          amount: 'amount',
          currency: 'currencyCode',
        },
      },
      ISO20022: {
        messageType: 'pacs.008',
        quantumFormat: 'ISO20022',
        fieldMapping: {
          debtor: 'sourceBankId',
          creditor: 'destinationBankId',
          amount: 'amount',
          currency: 'currencyCode',
        },
      },
      ACH: {
        messageType: 'ACH',
        quantumFormat: 'ISO20022',
        fieldMapping: {
          originator: 'sourceBankId',
          receiver: 'destinationBankId',
          amount: 'amount',
          currency: 'currencyCode',
        },
      },
      SEPA: {
        messageType: 'pain.001',
        quantumFormat: 'ISO20022',
        fieldMapping: {
          debtor: 'sourceBankId',
          creditor: 'destinationBankId',
          amount: 'amount',
          currency: 'currencyCode',
        },
      },
      PRIVATE_BANK: {
        messageType: 'PRIVATE',
        quantumFormat: 'ISO20022',
        fieldMapping: {
          from: 'sourceBankId',
          to: 'destinationBankId',
          value: 'amount',
          currency: 'currencyCode',
        },
      },
    };

    return defaultMappings[legacyProtocol] || {};
  }

  /**
   * Translate FX for legacy protocol
   */
  private async translateFx(data: {
    amount: string;
    currencyCode: string;
    legacyProtocol: string;
  }): Promise<{
    fxRate: Decimal;
    quantumAmount: Decimal;
    quantumCurrency: string;
  }> {
    // In production, would fetch real-time FX rates
    // For now, use 1:1 for same currency, or apply protocol-specific rates
    const amount = new Decimal(data.amount);

    // Default: quantum currency is same as legacy currency
    let quantumCurrency = data.currencyCode;
    let fxRate = new Decimal(1);

    // Protocol-specific FX adjustments
    switch (data.legacyProtocol) {
      case 'SWIFT':
        // SWIFT typically uses spot rates
        fxRate = new Decimal(1); // Placeholder
        break;
      case 'ISO20022':
        // ISO20022 uses reference rates
        fxRate = new Decimal(1); // Placeholder
        break;
      case 'ACH':
        // ACH uses domestic rates
        fxRate = new Decimal(1); // Placeholder
        break;
      case 'SEPA':
        // SEPA uses EUR rates
        if (data.currencyCode !== 'EUR') {
          // Convert to EUR
          quantumCurrency = 'EUR';
          fxRate = new Decimal(0.85); // Example EUR rate
        }
        break;
      default:
        fxRate = new Decimal(1);
    }

    const quantumAmount = amount.times(fxRate);

    return {
      fxRate,
      quantumAmount,
      quantumCurrency,
    };
  }

  /**
   * Translate risk for legacy protocol
   */
  private async translateRisk(data: {
    transactionData: any;
    legacyProtocol: string;
  }): Promise<{ riskScore: Decimal }> {
    // Base risk score
    let riskScore = new Decimal(0.1); // Low risk by default

    // Protocol-specific risk adjustments
    switch (data.legacyProtocol) {
      case 'SWIFT':
        // SWIFT has lower risk (established network)
        riskScore = new Decimal(0.05);
        break;
      case 'ISO20022':
        // ISO20022 has standardized risk
        riskScore = new Decimal(0.08);
        break;
      case 'ACH':
        // ACH has domestic risk
        riskScore = new Decimal(0.12);
        break;
      case 'SEPA':
        // SEPA has EU risk
        riskScore = new Decimal(0.06);
        break;
      case 'PRIVATE_BANK':
        // Private bank has higher risk
        riskScore = new Decimal(0.15);
        break;
    }

    // Additional risk factors from transaction data
    if (data.transactionData.amount > 1000000) {
      riskScore = riskScore.plus(0.1); // Large amount increases risk
    }

    return { riskScore };
  }

  /**
   * Get translation by ID
   */
  async getTranslation(translationId: string) {
    return await prisma.quantum_translations.findUnique({
      where: { translationId },
    });
  }

  /**
   * Get translations by protocol
   */
  async getTranslationsByProtocol(
    legacyProtocol: string,
    limit: number = 100
  ) {
    return await prisma.quantum_translations.findMany({
      where: { legacyProtocol },
      orderBy: { createdAt: 'desc' },
      take: limit,
    });
  }
}

export const quantumTranslationService = new QuantumTranslationService();