// Global Banking Identity Graph (GBIG) - Core Service

import prisma from '@/shared/database/prisma';
import { Decimal } from '@prisma/client/runtime/library';
import {
  IdentityNode,
  IdentityEdge,
  IdentityLayer,
  IdentityType,
  RelationshipType,
  KYCLevel,
  IdentityTrustScore,
  GBIGGraph,
  IdentityVerificationRequest,
  IdentityVerificationResult,
} from './types';
import { v4 as uuidv4 } from 'uuid';
import { logger } from '@/infrastructure/monitoring/logger';


export class GBIGService {
  /**
   * Calculate Identity Trust Score (ITS)
   * ITS = base_trust + (KYC_level * 10) + behavior_score - risk_penalties
   */
  calculateTrustScore(
    baseTrust: number,
    kycLevel: KYCLevel,
    behaviorScore: number,
    riskPenalties: number
  ): number {
    const its = baseTrust + kycLevel * 10 + behaviorScore - riskPenalties;
    return Math.max(0, Math.min(100, its)); // Clamp to 0-100
  }

  /**
   * Create or update an identity node
   */
  async createIdentityNode(
    identityType: IdentityType,
    layer: IdentityLayer,
    kycLevel: KYCLevel,
    sovereignBankId?: string,
    metadata?: Record<string, unknown>
  ): Promise<IdentityNode> {
    const identityId = `GBIG-${identityType}-${uuidv4()}`;
    const baseTrust = this.getBaseTrustForLayer(layer);
    const initialTrustScore = this.calculateTrustScore(
      baseTrust,
      kycLevel,
      50, // Default behavior score
      0 // No initial penalties
    );

    // Store in database (assuming Prisma schema exists)
    // For now, return the node structure
    const node: IdentityNode = {
      id: identityId,
      identityType,
      layer,
      sovereignBankId,
      kycLevel,
      trustScore: initialTrustScore,
      status: 'PENDING',
      createdAt: new Date(),
      updatedAt: new Date(),
      metadata,
    };

    logger.info(`Created GBIG identity node: ${identityId}`, { identityType, layer });

    return node;
  }

  /**
   * Create a relationship edge between two identity nodes
   */
  async createIdentityEdge(
    fromNodeId: string,
    toNodeId: string,
    relationshipType: RelationshipType,
    authorizationLevel: number = 50,
    metadata?: Record<string, unknown>
  ): Promise<IdentityEdge> {
    const edgeId = `GBIG-EDGE-${uuidv4()}`;

    const edge: IdentityEdge = {
      id: edgeId,
      fromNodeId,
      toNodeId,
      relationshipType,
      authorizationLevel: Math.max(0, Math.min(100, authorizationLevel)),
      createdAt: new Date(),
      updatedAt: new Date(),
      metadata,
    };

    logger.info(`Created GBIG edge: ${edgeId}`, {
      fromNodeId,
      toNodeId,
      relationshipType,
    });

    return edge;
  }

  /**
   * Update trust score for an identity
   */
  async updateTrustScore(
    identityId: string,
    factors: {
      transactionHistory?: number;
      amlFlags?: number;
      fxRiskExposure?: number;
      deviceSecurityPosture?: number;
    }
  ): Promise<IdentityTrustScore> {
    // Get existing identity
    // In real implementation, fetch from database
    const baseTrust = 50; // Default
    const kycLevel = KYCLevel.LEVEL_2; // Default, should fetch from DB
    const behaviorScore = this.calculateBehaviorScore(factors);
    const riskPenalties = this.calculateRiskPenalties(factors);

    const totalScore = this.calculateTrustScore(
      baseTrust,
      kycLevel,
      behaviorScore,
      riskPenalties
    );

    const trustScore: IdentityTrustScore = {
      identityId,
      baseTrust,
      kycLevel,
      behaviorScore,
      riskPenalties,
      totalScore,
      factors: {
        transactionHistory: factors.transactionHistory || 0,
        amlFlags: factors.amlFlags || 0,
        fxRiskExposure: factors.fxRiskExposure || 0,
        deviceSecurityPosture: factors.deviceSecurityPosture || 0,
      },
      calculatedAt: new Date(),
    };

    logger.info(`Updated trust score for ${identityId}`, { totalScore });

    return trustScore;
  }

  /**
   * Verify identity (KYC/KYB/Sovereign/Contract)
   */
  async verifyIdentity(
    request: IdentityVerificationRequest
  ): Promise<IdentityVerificationResult> {
    // In real implementation, perform verification based on type
    const verified = true; // Placeholder
    const trustScore = 75; // Placeholder
    const verificationLevel = KYCLevel.LEVEL_2; // Placeholder

    const result: IdentityVerificationResult = {
      identityId: request.identityId,
      verified,
      trustScore,
      verificationLevel,
    };

    logger.info(`Verified identity: ${request.identityId}`, {
      verificationType: request.verificationType,
      verified,
    });

    return result;
  }

  /**
   * Get the complete graph structure
   */
  async getGraph(sovereignBankId?: string): Promise<GBIGGraph> {
    // In real implementation, fetch from database
    const nodes: IdentityNode[] = [];
    const edges: IdentityEdge[] = [];

    return { nodes, edges };
  }

  /**
   * Get base trust score for a layer
   */
  private getBaseTrustForLayer(layer: IdentityLayer): number {
    switch (layer) {
      case IdentityLayer.SOVEREIGN:
        return 90; // Highest trust for sovereign entities
      case IdentityLayer.INSTITUTIONAL:
        return 70;
      case IdentityLayer.RETAIL:
        return 50;
      case IdentityLayer.CONTRACT:
        return 60;
      default:
        return 50;
    }
  }

  /**
   * Calculate behavior score from factors
   */
  private calculateBehaviorScore(factors: {
    transactionHistory?: number;
    amlFlags?: number;
    fxRiskExposure?: number;
    deviceSecurityPosture?: number;
  }): number {
    let score = 50; // Base behavior score

    // Positive factors
    if (factors.transactionHistory && factors.transactionHistory > 0) {
      score += Math.min(20, factors.transactionHistory * 0.1);
    }

    if (factors.deviceSecurityPosture && factors.deviceSecurityPosture > 0) {
      score += Math.min(15, factors.deviceSecurityPosture * 0.15);
    }

    // Negative factors
    if (factors.amlFlags && factors.amlFlags > 0) {
      score -= Math.min(30, factors.amlFlags * 5);
    }

    if (factors.fxRiskExposure && factors.fxRiskExposure > 0) {
      score -= Math.min(20, factors.fxRiskExposure * 0.1);
    }

    return Math.max(0, Math.min(100, score));
  }

  /**
   * Calculate risk penalties from factors
   */
  private calculateRiskPenalties(factors: {
    transactionHistory?: number;
    amlFlags?: number;
    fxRiskExposure?: number;
    deviceSecurityPosture?: number;
  }): number {
    let penalties = 0;

    if (factors.amlFlags && factors.amlFlags > 0) {
      penalties += factors.amlFlags * 10;
    }

    if (factors.fxRiskExposure && factors.fxRiskExposure > 50) {
      penalties += (factors.fxRiskExposure - 50) * 0.5;
    }

    return penalties;
  }

  /**
   * Register SCB with sovereign identity
   */
  async registerSCB(
    scbId: string,
    certificateHash: string,
    masterKeyId: string,
    hsmSignature: string
  ): Promise<IdentityNode> {
    return this.createIdentityNode(
      IdentityType.SCB,
      IdentityLayer.SOVEREIGN,
      KYCLevel.LEVEL_4,
      scbId,
      {
        certificateHash,
        masterKeyId,
        hsmSignature,
      }
    );
  }

  /**
   * Register smart contract identity
   */
  async registerContract(
    contractHashId: string,
    sovereignSignatoryList: string[],
    executionPermissions: string[]
  ): Promise<IdentityNode> {
    const node = await this.createIdentityNode(
      IdentityType.SMART_CONTRACT,
      IdentityLayer.CONTRACT,
      KYCLevel.LEVEL_2,
      undefined,
      {
        contractHashId,
        sovereignSignatoryList,
        executionPermissions,
      }
    );

    // Update with contract-specific fields
    node.contractHashId = contractHashId;
    node.sovereignSignatoryList = sovereignSignatoryList;
    node.executionPermissions = executionPermissions;

    return node;
  }
}

export const gbigService = new GBIGService();

