panels-origin/web-panel/composables/expenseAmounts.ts

export function roundMoney(value: number) {
  return Math.round((Number(value) || 0) * 100) / 100;
}

export function expenseAmounts(
  quantity: number,
  unitPrice: number,
  taxIncluded: boolean,
  ivaRate = 0.16,
) {
  const line = roundMoney(quantity * unitPrice);
  const rate = Number(ivaRate) || 0.16;
  if (taxIncluded) {
    const total = line;
    const subtotal = roundMoney(total / (1 + rate));
    return { subtotal, ivaAmount: roundMoney(total - subtotal), total };
  }
  const subtotal = line;
  const ivaAmount = roundMoney(subtotal * rate);
  return { subtotal, ivaAmount, total: roundMoney(subtotal + ivaAmount) };
}