const DEFAULT_BILLING_PERIOD_DAYS = 30;

export function calculateProratedUpgradeAmount(
    currentPlanPrice: number,
    requestedPlanPrice: number,
    remainingDays: number,
    billingPeriodDays = DEFAULT_BILLING_PERIOD_DAYS
): number {
    const dailyDifference = (requestedPlanPrice - currentPlanPrice) / billingPeriodDays;
    return Math.round(dailyDifference * remainingDays * 100) / 100;
}