// GPN Layer 1: Sovereign Access Layer
// SDIP authentication, sovereign traffic segmentation

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

export interface SovereignAccessRequest {
  sovereignBankId: string;
  messageType: string;
  messageData: Record<string, unknown>;
}

export interface SovereignAccessResult {
  accessId: string;
  authenticated: boolean;
  trafficSegment: string;
  rejectionReason?: string;
}

export class GpnSovereignAccessService {
  /**
   * Authenticate SCB node via SDIP
   */
  async authenticateSovereignNode(
    request: SovereignAccessRequest
  ): Promise<SovereignAccessResult> {
    const accessId = `GPN-ACCESS-${uuidv4()}`;

    try {
      // Get sovereign identity via SDIP (Sovereign Digital Identity Passport)
      const sovereignBank = await prisma.sovereignBank.findUnique({
        where: { id: request.sovereignBankId },
        include: {
          identities: {
            where: {
              identityType: 'Settlement',
              status: 'active',
            },
          },
        },
      });

      if (!sovereignBank) {
        return {
          accessId,
          authenticated: false,
          trafficSegment: 'rejected',
          rejectionReason: 'Sovereign bank not found',
        };
      }

      if (sovereignBank.status !== 'active') {
        return {
          accessId,
          authenticated: false,
          trafficSegment: 'rejected',
          rejectionReason: 'Sovereign bank is not active',
        };
      }

      if (sovereignBank.identities.length === 0) {
        return {
          accessId,
          authenticated: false,
          trafficSegment: 'rejected',
          rejectionReason: 'No active settlement identity found',
        };
      }

      // Verify SDIP identity (in production, this would validate HSM signatures)
      const identity = sovereignBank.identities[0];
      const isAuthenticated = await this.verifySdipIdentity(identity.id);

      if (!isAuthenticated) {
        return {
          accessId,
          authenticated: false,
          trafficSegment: 'rejected',
          rejectionReason: 'SDIP authentication failed',
        };
      }

      // Segment traffic by sovereign identity
      const trafficSegment = await this.segmentTrafficBySovereign(request.sovereignBankId);

      logger.info(`GPN Layer 1: Authenticated sovereign node ${request.sovereignBankId}`, {
        accessId,
        trafficSegment,
      });

      return {
        accessId,
        authenticated: true,
        trafficSegment,
      };
    } catch (error) {
      logger.error('GPN Layer 1: Authentication error', { error, request });
      return {
        accessId,
        authenticated: false,
        trafficSegment: 'rejected',
        rejectionReason: error instanceof Error ? error.message : 'Unknown error',
      };
    }
  }

  /**
   * Verify SDIP identity
   */
  private async verifySdipIdentity(identityId: string): Promise<boolean> {
    // In production, this would:
    // 1. Retrieve HSM-backed identity certificate
    // 2. Verify cryptographic signature
    // 3. Check certificate validity and revocation status
    // For now, simplified check
    const identity = await prisma.sovereignIdentity.findUnique({
      where: { id: identityId },
    });

    return identity !== null && identity.status === 'active';
  }

  /**
   * Segment traffic by sovereign identity
   */
  private async segmentTrafficBySovereign(sovereignBankId: string): Promise<string> {
    // Create traffic segment identifier
    // Format: SOV-{sovereignCode}
    const sovereignBank = await prisma.sovereignBank.findUnique({
      where: { id: sovereignBankId },
      select: { sovereignCode: true },
    });

    return `SOV-${sovereignBank?.sovereignCode || 'UNKNOWN'}`;
  }
}

export const gpnSovereignAccessService = new GpnSovereignAccessService();

