vyndr/src/services/payoutCalculator.js

function calculateStraightPayout(amount, odds) {
  if (odds < 0) {
    return amount + (amount / (Math.abs(odds) / 100));
  }
  return amount + (amount * (odds / 100));
}

function calculateParlayPayout(amount, legsOdds) {
  let multiplier = 1;
  for (const odds of legsOdds) {
    if (odds < 0) {
      multiplier *= 1 + (100 / Math.abs(odds));
    } else {
      multiplier *= 1 + (odds / 100);
    }
  }
  return amount * multiplier;
}

function calculatePayout(amount, betType, legsOdds) {
  if (!legsOdds || legsOdds.length === 0) return amount;

  if (betType === 'straight' || legsOdds.length === 1) {
    return Math.round(calculateStraightPayout(amount, legsOdds[0]) * 100) / 100;
  }

  // parlay, teaser, round_robin all use multiplied odds for MVP
  return Math.round(calculateParlayPayout(amount, legsOdds) * 100) / 100;
}

module.exports = { calculatePayout, calculateStraightPayout, calculateParlayPayout };