// Ramp Validation Service
// Validation and compliance checks for on/off-ramp transactions

import prisma from '@/shared/database/prisma';
import { logger } from '@/infrastructure/monitoring/logger';
import { createHash } from 'crypto';


export interface OnRampValidationRequest {
  dsezId: string;
  sourceType: string;
  targetType: string;
  amount: string;
  currencyCode: string;
  sourceBankId?: string;
}

export interface OffRampValidationRequest {
  dsezId: string;
  sourceType: string;
  targetType: string;
  amount: string;
  currencyCode: string;
  assetId?: string;
  destinationBankId?: string;
}

export interface ValidationResult {
  validated: boolean;
  complianceCheck: boolean;
  validationHash: string;
  reason?: string;
}

export class RampValidationService {
  /**
   * Validate on-ramp transaction
   */
  async validateOnRamp(
    request: OnRampValidationRequest
  ): Promise<ValidationResult> {
    logger.info('Ramp Validation: Validating on-ramp', { request });

    // Step 1: Verify D-SEZ is active
    const dsez = await prisma.digitalSovereignEconomicZone.findUnique({
      where: { dsezId: request.dsezId },
    });

    if (!dsez || dsez.status !== 'active') {
      return {
        validated: false,
        complianceCheck: false,
        validationHash: '',
        reason: 'D-SEZ not active',
      };
    }

    // Step 2: Verify liquidity flow is enabled
    if (!dsez.liquidityFlowEnabled) {
      return {
        validated: false,
        complianceCheck: false,
        validationHash: '',
        reason: 'Liquidity flow not enabled',
      };
    }

    // Step 3: Compliance checks
    const complianceCheck = await this.performComplianceCheck(request);

    // Step 4: Generate validation hash
    const validationHash = this.generateValidationHash({
      dsezId: request.dsezId,
      sourceType: request.sourceType,
      targetType: request.targetType,
      amount: request.amount,
      currencyCode: request.currencyCode,
      timestamp: new Date().toISOString(),
    });

    const validated = complianceCheck;

    logger.info('Ramp Validation: On-ramp validation completed', {
      validated,
      complianceCheck,
    });

    return {
      validated,
      complianceCheck,
      validationHash,
    };
  }

  /**
   * Validate off-ramp transaction
   */
  async validateOffRamp(
    request: OffRampValidationRequest
  ): Promise<ValidationResult> {
    logger.info('Ramp Validation: Validating off-ramp', { request });

    // Step 1: Verify D-SEZ is active
    const dsez = await prisma.digitalSovereignEconomicZone.findUnique({
      where: { dsezId: request.dsezId },
    });

    if (!dsez || dsez.status !== 'active') {
      return {
        validated: false,
        complianceCheck: false,
        validationHash: '',
        reason: 'D-SEZ not active',
      };
    }

    // Step 2: Verify liquidity flow is enabled
    if (!dsez.liquidityFlowEnabled) {
      return {
        validated: false,
        complianceCheck: false,
        validationHash: '',
        reason: 'Liquidity flow not enabled',
      };
    }

    // Step 3: If tokenized asset, verify it exists and is transferable
    if (request.sourceType === 'tokenized_asset' && request.assetId) {
      const asset = await prisma.metaverseAsset.findUnique({
        where: { assetId: request.assetId },
      });

      if (!asset || asset.status !== 'active') {
        return {
          validated: false,
          complianceCheck: false,
          validationHash: '',
          reason: 'Asset not available for off-ramp',
        };
      }
    }

    // Step 4: Compliance checks
    const complianceCheck = await this.performComplianceCheck(request);

    // Step 5: Generate validation hash
    const validationHash = this.generateValidationHash({
      dsezId: request.dsezId,
      sourceType: request.sourceType,
      targetType: request.targetType,
      amount: request.amount,
      currencyCode: request.currencyCode,
      assetId: request.assetId,
      timestamp: new Date().toISOString(),
    });

    const validated = complianceCheck;

    logger.info('Ramp Validation: Off-ramp validation completed', {
      validated,
      complianceCheck,
    });

    return {
      validated,
      complianceCheck,
      validationHash,
    };
  }

  /**
   * Perform compliance checks
   */
  private async performComplianceCheck(
    request: OnRampValidationRequest | OffRampValidationRequest
  ): Promise<boolean> {
    // In a full implementation, this would:
    // 1. Check AML/KYC compliance
    // 2. Verify transaction limits
    // 3. Check sanctions lists
    // 4. Verify source/destination bank status
    // 5. Check regulatory requirements

    // For now, return true if basic checks pass
    try {
      // Check amount is positive
      const amount = parseFloat(
        'amount' in request ? request.amount : '0'
      );
      if (amount <= 0) {
        return false;
      }

      // Additional compliance checks would go here
      return true;
    } catch (error) {
      logger.error('Ramp Validation: Compliance check error', { error });
      return false;
    }
  }

  /**
   * Generate validation hash
   */
  private generateValidationHash(data: Record<string, unknown>): string {
    const hash = createHash('sha256');
    hash.update(JSON.stringify(data));
    return hash.digest('hex');
  }
}

export const rampValidationService = new RampValidationService();

