// ZK-CBDC Validation: Mode 2 - ZK-Compliance Proofs (zkCP)
import { Prisma } from '@prisma/client';
// AML rules satisfied, sanctions clear, transaction within policy limits

import prisma from '@/shared/database/prisma';
import { v4 as uuidv4 } from 'uuid';
import { logger } from '@/infrastructure/monitoring/logger';
import { amlVelocityEngineService } from '@/core/compliance/ai/aml-velocity-engine.service';


export interface ZkComplianceProofRequest {
  walletId: string;
  transactionAmount: string;
  destinationWalletId: string;
  currencyCode: string;
}

export interface ZkComplianceProof {
  proofId: string;
  proofData: string;
  publicInputs: {
    walletId: string;
    compliant: boolean; // Only this is revealed, not the compliance details
    amlClear: boolean;
    sanctionsClear: boolean;
    policyCompliant: boolean;
  };
}

export class ZkComplianceProofService {
  /**
   * Generate ZK-Compliance Proof
   * Proves compliance without revealing compliance details
   */
  async generateComplianceProof(request: ZkComplianceProofRequest): Promise<ZkComplianceProof> {
    const proofId = `ZKCP-${uuidv4()}`;

    // Perform compliance checks (without revealing details in proof)
    const complianceChecks = await this.performComplianceChecks(request);

    // Check if all compliance checks pass
    const compliant =
      complianceChecks.amlClear &&
      complianceChecks.sanctionsClear &&
      complianceChecks.policyCompliant;

    if (!compliant) {
      throw new Error('Compliance check failed');
    }

    // Generate ZK proof
    const proofData = await this.generateZkProof({
      walletId: request.walletId,
      transactionAmount: request.transactionAmount,
      destinationWalletId: request.destinationWalletId,
      complianceChecks,
    });

    // Create proof record
    await prisma.zk_proofs.create({
      data: {
        id: uuidv4(),
        proofId,
        walletId: request.walletId,
        proofType: 'zkCP',
        proofData: proofData as string,
        publicInputs: {
          walletId: request.walletId,
          compliant: true,
          amlClear: true,
          sanctionsClear: true,
          policyCompliant: true,
        } as Prisma.InputJsonValue,
        verificationKey: 'default_zkcp_vk',
        status: 'verified',
        verifiedAt: new Date(),
        createdAt: new Date(),
        updatedAt: new Date(),
      },
    });

    logger.info('ZK-CBDC: Generated ZK-Compliance Proof', {
      proofId,
      walletId: request.walletId,
      compliant,
    });

    return {
      proofId,
      proofData,
      publicInputs: {
        walletId: request.walletId,
        compliant: true,
        amlClear: true,
        sanctionsClear: true,
        policyCompliant: true,
      },
    };
  }

  /**
   * Perform compliance checks
   */
  private async performComplianceChecks(request: ZkComplianceProofRequest): Promise<{
    amlClear: boolean;
    sanctionsClear: boolean;
    policyCompliant: boolean;
  }> {
    // AML check
    const amlAnomalies = await amlVelocityEngineService.detectVelocityAnomalies(
      request.walletId,
      'wallet',
      3600000 // 1 hour
    );
    const amlClear = amlAnomalies.length === 0;

    // Sanctions check (simplified)
    const sanctionsClear = await this.checkSanctions(request.walletId, request.destinationWalletId);

    // Policy compliance check
    const policyCompliant = await this.checkPolicyLimits(
      request.walletId,
      request.transactionAmount,
      request.currencyCode
    );

    return {
      amlClear,
      sanctionsClear,
      policyCompliant,
    };
  }

  /**
   * Check sanctions (simplified)
   */
  private async checkSanctions(walletId: string, destinationWalletId: string): Promise<boolean> {
    // In production, this would query sanctions screening system
    // For now, simplified check
    return true;
  }

  /**
   * Check policy limits
   */
  private async checkPolicyLimits(
    walletId: string,
    amount: string,
    currencyCode: string
  ): Promise<boolean> {
    // In production, this would check transaction limits, velocity limits, etc.
    // For now, simplified check
    const amountNum = parseFloat(amount);
    const maxTransactionLimit = 1000000; // $1M limit

    return amountNum <= maxTransactionLimit;
  }

  /**
   * Generate ZK proof (placeholder)
   */
  private async generateZkProof(data: {
    walletId: string;
    transactionAmount: string;
    destinationWalletId: string;
    complianceChecks: {
      amlClear: boolean;
      sanctionsClear: boolean;
      policyCompliant: boolean;
    };
  }): Promise<string> {
    // In production, use actual ZK library
    return JSON.stringify({
      type: 'zkCP',
      walletId: data.walletId,
      compliant: data.complianceChecks.amlClear && data.complianceChecks.sanctionsClear && data.complianceChecks.policyCompliant,
      proof: 'placeholder_zk_proof',
    });
  }

  /**
   * Verify ZK-Compliance Proof
   */
  async verifyComplianceProof(proofId: string): Promise<boolean> {
    const proof = await prisma.zk_proofs.findUnique({
      where: { proofId },
    });

    if (!proof || proof.proofType !== 'zkCP') {
      return false;
    }

    // Verify proof
    const publicInputs = proof.publicInputs as unknown as {
      compliant?: boolean;
      amlClear?: boolean;
      sanctionsClear?: boolean;
      policyCompliant?: boolean;
    };

    const isValid =
      publicInputs.compliant === true &&
      publicInputs.amlClear === true &&
      publicInputs.sanctionsClear === true &&
      publicInputs.policyCompliant === true;

    if (isValid) {
      await prisma.zk_proofs.update({
        where: { proofId },
        data: {
          status: 'verified',
          verifiedAt: new Date(),
        },
      });
    }

    return isValid;
  }
}

export const zkComplianceProofService = new ZkComplianceProofService();

