// DBIS International Arbitration Statutes (DIAS) - Core Service

import {
  ArbitrationCase,
  ArbitrationCaseType,
  ArbitrationPhase,
  ArbitrationPanel,
  ArbitrationSubmission,
  ArbitrationDecision,
  ArbitrationDecisionRequest,
  EnforcementAction,
  LedgerVerificationResult,
} from './types';
import { v4 as uuidv4 } from 'uuid';
import { logger } from '@/infrastructure/monitoring/logger';

export class DIASService {
  private cases: Map<string, ArbitrationCase> = new Map();

  /**
   * Submit a new arbitration case
   */
  async submitCase(submission: ArbitrationSubmission): Promise<ArbitrationCase> {
    logger.info('DIAS: New arbitration case submitted', {
      caseType: submission.caseType,
      claimant: submission.claimant.entityId,
      respondent: submission.respondent.entityId,
    });

    const caseId = `DIAS-CASE-${uuidv4()}`;

    const arbitrationCase: ArbitrationCase = {
      id: caseId,
      caseType: submission.caseType,
      phase: ArbitrationPhase.SUBMISSION,
      claimant: submission.claimant,
      respondent: submission.respondent,
      claim: {
        ...submission.claim,
        evidence: submission.claim.evidence.map((e) => ({
          ...e,
          timestamp: new Date(),
        })),
      },
      submittedAt: new Date(),
      metadata: submission.metadata,
    };

    // In real implementation, save to database
    logger.info(`DIAS: Case ${caseId} created`);

    return arbitrationCase;
  }

  /**
   * Verify ledger entries and signatures for a case
   */
  async verifyCase(caseId: string): Promise<{
    case: ArbitrationCase;
    verificationResults: LedgerVerificationResult[];
  }> {
    logger.info(`DIAS: Verifying case ${caseId}`);

    // In real implementation, fetch case from database
    const case_ = await this.getCase(caseId);

    if (case_.phase !== ArbitrationPhase.SUBMISSION) {
      throw new Error(`Case ${caseId} is not in SUBMISSION phase`);
    }

    const verificationResults: LedgerVerificationResult[] = [];

    // Verify ledger entries if provided
    if (case_.claim.evidence) {
      for (const evidence of case_.claim.evidence) {
        if (evidence.type === 'LEDGER_ENTRY') {
          const entryId = evidence.data.entryId as string;
          const ledgerId = evidence.data.ledgerId as string;

          // In real implementation, verify against actual ledger
          const verified = await this.verifyLedgerEntry(entryId, ledgerId);

          verificationResults.push({
            entryId,
            ledgerId,
            verified: verified.valid,
            signatureValid: verified.signatureValid,
            timestampValid: verified.timestampValid,
            amountMatches: verified.amountMatches,
            issues: verified.issues,
          });
        }
      }
    }

    // Update case phase to VERIFICATION
    case_.phase = ArbitrationPhase.VERIFICATION;
    case_.ledgerEntries = verificationResults.map((r) => ({
      entryId: r.entryId,
      ledgerId: r.ledgerId,
      verified: r.verified,
    }));

    this.cases.set(caseId, case_);
    logger.info(`DIAS: Case ${caseId} verified`);

    return { case: case_, verificationResults };
  }

  /**
   * Assign arbitration panel
   */
  async assignPanel(caseId: string): Promise<ArbitrationPanel> {
    logger.info(`DIAS: Assigning panel for case ${caseId}`);

    const case_ = await this.getCase(caseId);

    if (case_.phase !== ArbitrationPhase.VERIFICATION) {
      throw new Error(`Case ${caseId} is not in VERIFICATION phase`);
    }

    // In real implementation, select panel members based on rules
    const panel: ArbitrationPanel = {
      id: `DIAS-PANEL-${uuidv4()}`,
      caseId,
      scbRepresentative: {
        identityId: 'SCB-REP-001', // Placeholder
        sovereignBankId: case_.claimant.entityType === 'SCB' ? case_.claimant.entityId : case_.respondent.entityId,
        name: 'SCB Representative', // Placeholder
      },
      dbisLegalAuthority: {
        identityId: 'DBIS-LEGAL-001', // Placeholder
        name: 'DBIS Legal Authority', // Placeholder
        title: 'Chief Legal Officer',
      },
      independentArbitrator: {
        identityId: 'IND-ARB-001', // Placeholder
        name: 'Independent Arbitrator', // Placeholder
        credentials: ['International Arbitration Certification'],
      },
      assignedAt: new Date(),
    };

    case_.panel = panel;
    case_.phase = ArbitrationPhase.HEARING;

    // In real implementation, save to database
    logger.info(`DIAS: Panel ${panel.id} assigned to case ${caseId}`);

    return panel;
  }

  /**
   * Make arbitration decision
   */
  async makeDecision(
    request: ArbitrationDecisionRequest
  ): Promise<ArbitrationCase> {
    logger.info(`DIAS: Making decision for case ${request.caseId}`);

    const case_ = await this.getCase(request.caseId);

    if (case_.phase !== ArbitrationPhase.HEARING) {
      throw new Error(`Case ${request.caseId} is not in HEARING phase`);
    }

    if (!case_.panel) {
      throw new Error(`Case ${request.caseId} has no assigned panel`);
    }

    case_.decision = {
      decision: request.decision,
      reasoning: request.reasoning,
      awardedAmount: request.awardedAmount,
      currencyCode: request.currencyCode,
      decidedAt: new Date(),
      decidedBy: case_.panel.id,
    };

    case_.phase = ArbitrationPhase.DECISION;

    // Generate enforcement actions
    case_.enforcement = await this.generateEnforcementActions(case_);
    this.cases.set(request.caseId, case_);

    logger.info(`DIAS: Decision made for case ${request.caseId}`, {
      decision: request.decision,
    });

    return case_;
  }

  /**
   * Execute enforcement actions
   */
  async executeEnforcement(caseId: string): Promise<ArbitrationCase> {
    logger.info(`DIAS: Executing enforcement for case ${caseId}`);

    const case_ = await this.getCase(caseId);

    if (case_.phase !== ArbitrationPhase.DECISION) {
      throw new Error(`Case ${caseId} is not in DECISION phase`);
    }

    if (!case_.enforcement) {
      throw new Error(`Case ${caseId} has no enforcement actions`);
    }

    if (case_.enforcement.executed) {
      throw new Error(`Case ${caseId} enforcement already executed`);
    }

    // Execute each action
    for (const action of case_.enforcement.actions) {
      await this.executeEnforcementAction(case_, action);
    }

    case_.enforcement.executed = true;
    case_.enforcement.executedAt = new Date();
    case_.phase = ArbitrationPhase.EXECUTION;

    // In real implementation, save to database
    logger.info(`DIAS: Enforcement executed for case ${caseId}`);

    return case_;
  }

  /**
   * Close a case
   */
  async closeCase(caseId: string): Promise<ArbitrationCase> {
    logger.info(`DIAS: Closing case ${caseId}`);

    const case_ = await this.getCase(caseId);

    if (case_.phase !== ArbitrationPhase.EXECUTION) {
      throw new Error(`Case ${caseId} is not in EXECUTION phase`);
    }

    case_.phase = ArbitrationPhase.CLOSED;
    case_.closedAt = new Date();
    this.cases.set(caseId, case_);

    logger.info(`DIAS: Case ${caseId} closed`);

    return case_;
  }

  /**
   * Get a case by ID
   * Uses in-memory store. For production, replace with database fetch.
   */
  async getCase(caseId: string): Promise<ArbitrationCase> {
    const c = this.cases.get(caseId);
    if (c) return c;
    throw new Error(
      `Case ${caseId} not found. Integrate DIAS with database for persistence.`
    );
  }

  /**
   * Verify a ledger entry
   */
  private async verifyLedgerEntry(
    entryId: string,
    ledgerId: string
  ): Promise<{
    valid: boolean;
    signatureValid: boolean;
    timestampValid: boolean;
    amountMatches: boolean;
    issues?: string[];
  }> {
    // In real implementation, verify against actual ledger
    logger.info(`DIAS: Verifying ledger entry ${entryId} in ledger ${ledgerId}`);

    return {
      valid: true,
      signatureValid: true,
      timestampValid: true,
      amountMatches: true,
    };
  }

  /**
   * Generate enforcement actions based on decision
   */
  private async generateEnforcementActions(
    case_: ArbitrationCase
  ): Promise<{ actions: EnforcementAction[]; executed: boolean }> {
    const actions: EnforcementAction[] = [];

    if (!case_.decision) {
      return { actions: [], executed: false };
    }

    // If decision favors claimant and involves monetary award
    if (
      (case_.decision.decision === ArbitrationDecision.FAVOR_CLAIMANT ||
        case_.decision.decision === ArbitrationDecision.PARTIAL) &&
      case_.decision.awardedAmount
    ) {
      actions.push(EnforcementAction.SETTLEMENT_REVERSAL);
      actions.push(EnforcementAction.ACCOUNT_FREEZE);
    }

    // If case involves contract violation
    if (case_.caseType === ArbitrationCaseType.CBDC_CONTRACT_VIOLATION) {
      actions.push(EnforcementAction.SUSPENSION_OF_PRIVILEGES);
    }

    // If case involves significant dispute
    if (case_.claim.amount) {
      const amount = parseFloat(case_.claim.amount);
      if (amount > 1000000) {
        // Large amount threshold
        actions.push(EnforcementAction.LIQUIDITY_PENALTY);
      }
    }

    // If no actions needed
    if (actions.length === 0) {
      actions.push(EnforcementAction.NO_ACTION);
    }

    return { actions, executed: false };
  }

  /**
   * Execute a specific enforcement action
   */
  private async executeEnforcementAction(
    case_: ArbitrationCase,
    action: EnforcementAction
  ): Promise<void> {
    logger.info(`DIAS: Executing enforcement action ${action} for case ${case_.id}`);

    switch (action) {
      case EnforcementAction.ACCOUNT_FREEZE:
        // In real implementation, freeze accounts via account service
        logger.info(`DIAS: Freezing accounts for case ${case_.id}`);
        break;

      case EnforcementAction.SETTLEMENT_REVERSAL:
        // In real implementation, reverse settlement via settlement service
        if (case_.decision?.awardedAmount) {
          logger.info(
            `DIAS: Reversing settlement of ${case_.decision.awardedAmount} for case ${case_.id}`
          );
        }
        break;

      case EnforcementAction.LIQUIDITY_PENALTY:
        // In real implementation, apply penalty via treasury service
        logger.info(`DIAS: Applying liquidity penalty for case ${case_.id}`);
        break;

      case EnforcementAction.SUSPENSION_OF_PRIVILEGES:
        // In real implementation, suspend privileges via governance service
        logger.info(`DIAS: Suspending privileges for case ${case_.id}`);
        break;

      case EnforcementAction.NO_ACTION:
        logger.info(`DIAS: No action required for case ${case_.id}`);
        break;
    }
  }
}

export const diasService = new DIASService();

