// ISP Temporal Settlement Engine Service
// TSE pre-commitment and state estimation

import prisma from '@/shared/database/prisma';
import { v4 as uuidv4 } from 'uuid';
import { createHash } from 'crypto';


export interface CreateTSERequest {
  settlementId: string;
  futureStateEstimate: Record<string, unknown>;
  communicationDelay: number; // Delay in seconds
  predictiveContract?: Record<string, unknown>;
}

export interface TSEResult {
  tseId: string;
  preCommitHash: string;
  status: string;
}

export class IspTemporalService {
  /**
   * Create temporal settlement engine pre-commitment
   * Formula: settlement_pre_commit = HASH(future_state_estimate)
   */
  async createTSE(request: CreateTSERequest): Promise<TSEResult> {
    // Verify settlement exists
    const settlement = await prisma.interplanetary_settlements.findUnique({
      where: { settlementId: request.settlementId },
    });

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

    // Calculate pre-commit hash: HASH(future_state_estimate)
    const futureStateStr = JSON.stringify(request.futureStateEstimate);
    const preCommitHash = createHash('sha3-256').update(futureStateStr).digest('hex');

    const tseId = `ISP-TSE-${uuidv4()}`;

    const tse = await prisma.temporal_settlement_engine.create({
      data: {
        tseId,
        settlementId: request.settlementId,
        futureStateEstimate: request.futureStateEstimate,
        preCommitHash,
        communicationDelay: request.communicationDelay,
        predictiveContract: request.predictiveContract || null,
        status: 'pending',
      },
    });

    return {
      tseId: tse.tseId,
      preCommitHash: tse.preCommitHash,
      status: tse.status,
    };
  }

  /**
   * Commit TSE pre-commitment
   */
  async commitTSE(tseId: string): Promise<void> {
    await prisma.temporal_settlement_engine.update({
      where: { tseId },
      data: {
        status: 'committed',
        committedAt: new Date(),
      },
    });
  }

  /**
   * Verify TSE pre-commitment
   */
  async verifyTSE(tseId: string, futureStateEstimate: Record<string, unknown>): Promise<boolean> {
    const tse = await prisma.temporal_settlement_engine.findUnique({
      where: { tseId },
    });

    if (!tse) {
      return false;
    }

    // Recalculate hash
    const futureStateStr = JSON.stringify(futureStateEstimate);
    const calculatedHash = createHash('sha3-256').update(futureStateStr).digest('hex');

    // Verify hash matches
    if (calculatedHash !== tse.preCommitHash) {
      return false;
    }

    // Update status
    await prisma.temporal_settlement_engine.update({
      where: { tseId },
      data: {
        status: 'verified',
        verifiedAt: new Date(),
      },
    });

    return true;
  }

  /**
   * Get TSE
   */
  async getTSE(tseId: string) {
    return await prisma.temporal_settlement_engine.findUnique({
      where: { tseId },
      include: {
        settlement: true,
      },
    });
  }

  /**
   * Get TSE by settlement
   */
  async getTSEBySettlement(settlementId: string) {
    return await prisma.temporal_settlement_engine.findUnique({
      where: { settlementId },
      include: {
        settlement: true,
      },
    });
  }
}

export const ispTemporalService = new IspTemporalService();

