brazil-swift-ops/packages/rules-engine/src/threshold.ts

import type {
  Transaction,
  ThresholdCheckResult,
  RuleResult,
  RuleSeverity,
  RuleDecision,
} from '@brazil-swift-ops/types';
import { getDefaultConverter } from '@brazil-swift-ops/utils';
import { getConfig } from './config';

export function evaluateThreshold(
  transaction: Transaction
): ThresholdCheckResult {
  const config = getConfig();
  const converter = getDefaultConverter();

  const usdEquivalent = converter.getUSDEquivalent(
    transaction.amount,
    transaction.currency
  );

  const threshold = config.threshold.usdReportingThreshold;
  const requiresReporting = usdEquivalent >= threshold;

  return {
    passed: true,
    transactionAmount: transaction.amount,
    currency: transaction.currency,
    usdEquivalent,
    threshold,
    requiresReporting,
    rationale: requiresReporting
      ? `Transaction amount (${transaction.amount} ${transaction.currency} = ${usdEquivalent.toFixed(2)} USD) exceeds reporting threshold of ${threshold} USD. Reporting to Banco Central required.`
      : `Transaction amount (${transaction.amount} ${transaction.currency} = ${usdEquivalent.toFixed(2)} USD) is below reporting threshold of ${threshold} USD.`,
  };
}

export function createThresholdRuleResult(
  check: ThresholdCheckResult
): RuleResult {
  const severity: RuleSeverity = check.requiresReporting ? 'Warning' : 'Info';
  const decision: RuleDecision = check.requiresReporting ? 'Hold' : 'Allow';

  return {
    ruleId: 'threshold-check',
    ruleName: 'USD Equivalent Threshold Check',
    passed: true,
    severity,
    decision,
    rationale: check.rationale,
    details: {
      transactionAmount: check.transactionAmount,
      currency: check.currency,
      usdEquivalent: check.usdEquivalent,
      threshold: check.threshold,
      requiresReporting: check.requiresReporting,
    },
  };
}