// Quantum Bond Systems Service
// Q-Bonds and timeline-synchronized bonds

import prisma from '@/shared/database/prisma';
import { Decimal } from '@prisma/client/runtime/library';
import { v4 as uuidv4 } from 'uuid';
import { logger } from '@/infrastructure/monitoring/logger';
import { createHash } from 'crypto';


export type QuantumBondType = 'q_bond' | 'timeline_synchronized';

export interface IssueQuantumBondRequest {
  bondName: string;
  principalAmount: string;
  bondType: QuantumBondType;
  maturityYears: number;
  couponRate: string;
}

export interface TimelineSyncRequest {
  quantumBondId: string;
  timelineType: 't0' | 't_minus_delta' | 't_plus_delta';
  timelineState: Record<string, any>;
}

export class QuantumBondsService {
  /**
   * Issue quantum bond
   */
  async issueQuantumBond(request: IssueQuantumBondRequest): Promise<string> {
    logger.info('GRU: Issuing quantum bond', { request });

    const bondId = `QBOND-${uuidv4()}`;
    const maturityDate = new Date();
    maturityDate.setFullYear(maturityDate.getFullYear() + request.maturityYears);

    // Initialize quantum state
    const quantumState = {
      superposition: true,
      collapsed: false,
      observers: [],
      truthSampling: null,
    };

    const bond = await prisma.quantumBond.create({
      data: {
        bondId,
        bondName: request.bondName,
        principalAmount: new Decimal(request.principalAmount),
        bondType: request.bondType,
        quantumState: JSON.stringify(quantumState),
        observerCount: 0,
        maturityDate,
        couponRate: new Decimal(request.couponRate),
        status: 'active',
        issuedAt: new Date(),
      },
    });

    logger.info('GRU: Quantum bond issued', { bondId, bondType: request.bondType });

    return bondId;
  }

  /**
   * Collapse quantum bond (quantum truth sampling)
   */
  async collapseQuantumBond(bondId: string, observerId: string): Promise<string> {
    logger.info('GRU: Collapsing quantum bond', { bondId, observerId });

    const bond = await prisma.quantumBond.findUnique({
      where: { bondId },
    });

    if (!bond || bond.status !== 'active') {
      throw new Error(`Bond not found or not active: ${bondId}`);
    }

    // Quantum truth sampling
    const truthSamplingHash = createHash('sha256')
      .update(`${bondId}-${observerId}-${Date.now()}`)
      .digest('hex');

    // Update observer count
    const observerCount = bond.observerCount + 1;

    // Collapse state if double observer
    let status = bond.status;
    let collapsedAt = bond.collapsedAt;
    if (observerCount >= 2) {
      status = 'collapsed';
      collapsedAt = new Date();
    }

    // Update quantum state
    const quantumState = bond.quantumState ? JSON.parse(bond.quantumState as string) : {};
    quantumState.collapsed = observerCount >= 2;
    quantumState.observers = [...(quantumState.observers || []), observerId];
    quantumState.truthSampling = truthSamplingHash;

    await prisma.quantumBond.update({
      where: { bondId },
      data: {
        quantumState: JSON.stringify(quantumState),
        truthSamplingHash,
        observerCount,
        status,
        collapsedAt,
      },
    });

    logger.info('GRU: Quantum bond collapsed', { bondId, observerCount });

    return truthSamplingHash;
  }

  /**
   * Synchronize timeline
   */
  async synchronizeTimeline(request: TimelineSyncRequest): Promise<string> {
    logger.info('GRU: Synchronizing timeline', { request });

    const bond = await prisma.quantumBond.findUnique({
      where: { bondId: request.quantumBondId },
    });

    if (!bond) {
      throw new Error(`Quantum bond not found: ${request.quantumBondId}`);
    }

    const syncId = `SYNC-${uuidv4()}`;

    await prisma.timelineSynchronizedBond.create({
      data: {
        syncId,
        quantumBondId: request.quantumBondId,
        timelineType: request.timelineType,
        timelineState: JSON.stringify(request.timelineState),
        syncStatus: 'synced',
        syncedAt: new Date(),
      },
    });

    // Merge timeline states if all timelines are synced
    await this.mergeTimelineStates(request.quantumBondId);

    logger.info('GRU: Timeline synchronized', { syncId });

    return syncId;
  }

  /**
   * Merge timeline states: Bond_tΩ = Merge(Bond_t0, Bond_t−Δ, Bond_t+Δ)
   */
  private async mergeTimelineStates(quantumBondId: string): Promise<void> {
    const timelines = await prisma.timelineSynchronizedBond.findMany({
      where: {
        quantumBondId,
        syncStatus: 'synced',
      },
    });

    if (timelines.length < 3) {
      // Need all three timelines
      return;
    }

    const t0 = timelines.find((t) => t.timelineType === 't0');
    const tMinus = timelines.find((t) => t.timelineType === 't_minus_delta');
    const tPlus = timelines.find((t) => t.timelineType === 't_plus_delta');

    if (!t0 || !tMinus || !tPlus) {
      return;
    }

    // Merge states
    const mergedState = {
      t0: t0.timelineState ? JSON.parse(t0.timelineState as string) : {},
      t_minus_delta: tMinus.timelineState ? JSON.parse(tMinus.timelineState as string) : {},
      t_plus_delta: tPlus.timelineState ? JSON.parse(tPlus.timelineState as string) : {},
      merged: {
        mergedAt: new Date(),
        consensus: true,
      },
    };

    await prisma.quantumBond.update({
      where: { bondId: quantumBondId },
      data: {
        timelineStates: JSON.stringify({
          t0: t0.timelineState,
          t_minus_delta: tMinus.timelineState,
          t_plus_delta: tPlus.timelineState,
        }),
        mergedState: JSON.stringify(mergedState),
        mergedAt: new Date(),
        status: 'merged',
      },
    });

    // Mark timelines as merged
    await prisma.timelineSynchronizedBond.updateMany({
      where: {
        quantumBondId,
        syncStatus: 'synced',
      },
      data: {
        syncStatus: 'merged',
      },
    });

    logger.info('GRU: Timeline states merged', { quantumBondId });
  }

  /**
   * Pay quantum bond coupon
   */
  async payQuantumBondCoupon(bondId: string): Promise<string> {
    const bond = await prisma.quantumBond.findUnique({
      where: { bondId },
    });

    if (!bond || bond.status !== 'active') {
      throw new Error(`Bond not found or not active: ${bondId}`);
    }

    // Quantum settlement requires truth sampling
    if (bond.bondType === 'q_bond' && !bond.truthSamplingHash) {
      throw new Error('Quantum bond must be collapsed before coupon payment');
    }

    const couponAmount = bond.principalAmount.times(bond.couponRate);
    const couponId = `COUPON-${uuidv4()}`;
    const truthSamplingHash = bond.truthSamplingHash || createHash('sha256').update(`${bondId}-${Date.now()}`).digest('hex');

    await prisma.quantumBondCoupon.create({
      data: {
        couponId,
        bondId,
        couponAmount,
        paymentDate: new Date(),
        quantumSettled: bond.bondType === 'q_bond',
        truthSamplingHash,
        status: 'quantum_settled',
        settledAt: new Date(),
      },
    });

    logger.info('GRU: Quantum bond coupon paid', { bondId });

    return couponId;
  }

  /**
   * Get quantum bond
   */
  async getQuantumBond(bondId: string) {
    return await prisma.quantumBond.findUnique({
      where: { bondId },
      include: {
        coupons: {
          orderBy: { paymentDate: 'desc' },
        },
        timelineSyncs: {
          orderBy: { syncedAt: 'desc' },
        },
      },
    });
  }

  /**
   * Get quantum bonds by type
   */
  async getQuantumBondsByType(bondType: QuantumBondType) {
    return await prisma.quantumBond.findMany({
      where: {
        bondType,
        status: 'active',
      },
      include: {
        coupons: true,
        timelineSyncs: true,
      },
    });
  }
}

export const quantumBondsService = new QuantumBondsService();

