// Bond Settlement Service
// QPS → GAS → Ω-Layer → DBIS Prime pipeline

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';
import { atomicSettlementService } from '@/core/settlement/isn/atomic-settlement.service';
import { omegaLayerService } from './omega-layer.service';


export interface BondSettlementRequest {
  bondId?: string;
  syntheticBondId?: string;
  sourceBankId: string;
  destinationBankId: string;
  amount: string;
  currencyCode: string;
}

export interface BondSettlementResult {
  settlementId: string;
  qpsTransactionId?: string;
  gasSettlementId?: string;
  omegaLayerHash?: string;
  primeLedgerHash?: string;
  status: string;
}

export class BondSettlementService {
  /**
   * Execute bond settlement through full pipeline
   * Pipeline: Bond Issuance → QPS → GAS Atomic Network → Ω-Layer → DBIS Prime Ledger
   */
  async executeBondSettlement(request: BondSettlementRequest): Promise<BondSettlementResult> {
    logger.info('GRU: Executing bond settlement', { request });

    const settlementId = `BSETTLE-${uuidv4()}`;

    // Create settlement record
    const settlement = await prisma.gru_bond_settlements.create({
      data: {
        id: uuidv4(),
        settlementId,
        bondId: request.bondId,
        syntheticBondId: request.syntheticBondId,
        sourceBankId: request.sourceBankId,
        destinationBankId: request.destinationBankId,
        amount: new Decimal(request.amount),
        currencyCode: request.currencyCode,
        settlementStage: 'issuance',
        createdAt: new Date(),
        updatedAt: new Date(),
        status: 'pending',
      },
    });

    try {
      // Stage 1: QPS (Quantum Proxy Server)
      const qpsResult = await this.executeQPSStage(settlementId, request);
      await this.updateSettlementStage(settlementId, 'qps', 'completed', {
        qpsTransactionId: qpsResult.transactionId,
      });

      // Stage 2: GAS Atomic Network
      const gasResult = await this.executeGASStage(settlementId, request, qpsResult.transactionId);
      await this.updateSettlementStage(settlementId, 'gas', 'completed', {
        gasSettlementId: gasResult.settlementId,
      });

      // Stage 3: Ω-Layer
      const omegaResult = await this.executeOmegaLayerStage(settlementId, gasResult);
      await this.updateSettlementStage(settlementId, 'omega_layer', 'completed', {
        omegaLayerHash: omegaResult.hash,
      });

      // Stage 4: DBIS Prime Ledger
      const primeResult = await this.executePrimeLedgerStage(settlementId, omegaResult);
      await this.updateSettlementStage(settlementId, 'prime_ledger', 'completed', {
        primeLedgerHash: primeResult.hash,
      });

      // Finalize settlement
      await prisma.gru_bond_settlements.update({
        where: { settlementId },
        data: {
          status: 'settled',
          qpsTransactionId: qpsResult.transactionId,
          gasSettlementId: gasResult.settlementId,
          omegaLayerHash: omegaResult.hash,
          primeLedgerHash: primeResult.hash,
          qpsCompletedAt: new Date(),
          gasCompletedAt: new Date(),
          omegaCompletedAt: new Date(),
          settledAt: new Date(),
        },
      });

      logger.info('GRU: Bond settlement completed', { settlementId });

      return {
        settlementId,
        qpsTransactionId: qpsResult.transactionId,
        gasSettlementId: gasResult.settlementId,
        omegaLayerHash: omegaResult.hash,
        primeLedgerHash: primeResult.hash,
        status: 'settled',
      };
    } catch (error) {
      // Mark settlement as failed
      await prisma.gru_bond_settlements.update({
        where: { settlementId },
        data: {
          status: 'failed',
        },
      });

      logger.error('GRU: Bond settlement failed', { settlementId, error });
      throw error;
    }
  }

  /**
   * Execute QPS stage
   */
  private async executeQPSStage(settlementId: string, request: BondSettlementRequest): Promise<{ transactionId: string }> {
    logger.info('GRU: Executing QPS stage', { settlementId });

    // Bridge transaction through QPS (simplified - would use actual QPS service)
    // For now, generate QPS transaction ID
    const qpsTransactionId = `QPS-${uuidv4()}`;

    // In production, would call:
    // const qpsResult = await quantumProxyService.bridgeTransaction({
    //   legacyTransactionId: settlementId,
    //   legacyProtocol: 'DBIS_BOND',
    //   sourceBankId: request.sourceBankId,
    //   destinationBankId: request.destinationBankId,
    //   amount: request.amount,
    //   currencyCode: request.currencyCode,
    //   transactionData: { bondId: request.bondId, syntheticBondId: request.syntheticBondId },
    // });

    return { transactionId: qpsTransactionId };
  }

  /**
   * Execute GAS Atomic Network stage
   */
  private async executeGASStage(
    settlementId: string,
    request: BondSettlementRequest,
    qpsTransactionId: string
  ): Promise<{ settlementId: string }> {
    logger.info('GRU: Executing GAS stage', { settlementId });

    // Execute atomic settlement
    const gasResult = await atomicSettlementService.executeAtomicSettlement({
      sourceBankId: request.sourceBankId,
      destinationBankId: request.destinationBankId,
      amount: parseFloat(request.amount),
      currencyCode: request.currencyCode,
      assetType: 'security',
      transactionId: qpsTransactionId,
    });

    return { settlementId: gasResult.settlementId };
  }

  /**
   * Execute Ω-Layer stage
   */
  private async executeOmegaLayerStage(settlementId: string, gasResult: { settlementId: string }): Promise<{ hash: string }> {
    logger.info('GRU: Executing Ω-Layer stage', { settlementId });

    // Get settlement for reality states
    const settlement = await prisma.gru_bond_settlements.findUnique({
      where: { settlementId },
    });

    if (!settlement) {
      throw new Error(`Settlement not found: ${settlementId}`);
    }

    // Ω-Layer finality verification
    const omegaResult = await omegaLayerService.verifyFinality({
      settlementId,
      gasSettlementId: gasResult.settlementId,
      bondId: settlement.bondId || undefined,
      syntheticBondId: settlement.syntheticBondId || undefined,
    });

    return { hash: omegaResult.hash };
  }

  /**
   * Execute DBIS Prime Ledger stage
   */
  private async executePrimeLedgerStage(settlementId: string, omegaResult: { hash: string }): Promise<{ hash: string }> {
    logger.info('GRU: Executing Prime Ledger stage', { settlementId });

    // Prime Ledger posting (would integrate with prime ledger service)
    // For now, generate hash
    const primeHash = `PRIME-${uuidv4()}-${omegaResult.hash}`;

    // In production, would call prime ledger service
    // const primeResult = await primeLedgerService.postTransaction(settlementId, omegaResult.hash);

    return { hash: primeHash };
  }

  /**
   * Update settlement stage
   */
  private async updateSettlementStage(
    settlementId: string,
    stage: string,
    stageStatus: string,
    stageData?: Record<string, any>
  ): Promise<void> {
    await prisma.bondSettlementPipeline.create({
      data: {
        pipelineId: `PIPELINE-${uuidv4()}`,
        settlementId,
        stage,
        stageStatus,
        stageData: stageData ? JSON.stringify(stageData) : null,
        startedAt: new Date(),
        completedAt: stageStatus === 'completed' ? new Date() : null,
      },
    });
  }

  /**
   * Reconcile perpetual bond state across realities
   * PerpetualState = Merge(classical, quantum, parallel, holo)
   */
  async reconcilePerpetualState(bondId: string): Promise<Record<string, any>> {
    logger.info('GRU: Reconciling perpetual bond state', { bondId });

    // Get classical state
    const classicalState = await prisma.gru_bonds.findUnique({
      where: { bondId },
    });

    // Get quantum state (if exists)
    const quantumBond = await prisma.quantum_bonds.findFirst({
      where: { bondId },
    });

    // Get parallel state (simplified - would use parallel reality service)
    const parallelState = null; // Would fetch from parallel reality service

    // Get holographic state (simplified - would use holographic service)
    const holographicState = null; // Would fetch from holographic service

    // Merge states
    const mergedState = {
      classical: classicalState,
      quantum: quantumBond,
      parallel: parallelState,
      holographic: holographicState,
      merged: {
        principalAmount: classicalState?.principalAmount || new Decimal(0),
        status: classicalState?.status || 'unknown',
        mergedAt: new Date(),
      },
    };

    // Update settlement with merged state
    await prisma.gru_bond_settlements.updateMany({
      where: { bondId },
      data: {
        perpetualState: JSON.stringify(mergedState),
      },
    });

    logger.info('GRU: Perpetual bond state reconciled', { bondId });

    return mergedState;
  }

  /**
   * Get settlement by ID
   */
  async getSettlement(settlementId: string) {
    return await prisma.gru_bond_settlements.findUnique({
      where: { settlementId },
      include: {
        bond: true,
        syntheticBond: true,
        pipelineSteps: {
          orderBy: { createdAt: 'asc' },
        },
      },
    });
  }

  /**
   * Get settlements for bond
   */
  async getSettlementsForBond(bondId?: string, syntheticBondId?: string) {
    return await prisma.gru_bond_settlements.findMany({
      where: {
        bondId: bondId || undefined,
        syntheticBondId: syntheticBondId || undefined,
      },
      orderBy: { createdAt: 'desc' },
      include: {
        pipelineSteps: true,
      },
    });
  }
}

export const bondSettlementService = new BondSettlementService();

