/// <summary>
/// Applies a discount to an order by reducing product prices.
/// </summary>
/// <param name="products">The order on which to apply a discount.</param>
/// <param name="discount">The amount to deduct from the products.</param>
/// <returns>Returns the amount of unused discount.</returns>
public static decimal ApplyDiscount(this IList <ProcessOrderProduct> products, decimal discount)
{
products.CheckNotNull(nameof(products));
discount.CheckRange(nameof(discount), min: 0);
var edited = false;
while (discount > 0 && GetProductWithPrice(out var product))
{
if (product.Quantity > 1)
{
// Split product so we edit the price of only 1 item.
product.Quantity--;
product = new ProcessOrderProduct(product.Name, product.Price);
products.Add(product);
}
var reduce = Math.Min(discount, product.Price);
product.Price -= reduce;
discount -= reduce;
edited = true;
}
if (edited)
{
GroupDuplicates(products);
}
return(discount);
bool GetProductWithPrice(out ProcessOrderProduct product)
{
product = products.FirstOrDefault(x => x.Price > 0);
return(product != null);
}
}
/// <summary>
/// Returns the list of products to settle due payments.
/// </summary>
/// <param name="contact">The contact to create the bill for.</param>
/// <param name="planList">The list of due payment plans.</param>
/// <param name="currentDate">The current date, ensuring all calculations are done using the exact same date.</param>
/// <param name="deduct">An amount to deduct from the order, such as account credits.</param>
/// <returns>The list of products to pay.</returns>
public IList <ProcessOrderProduct> GetBillProducts(ApiCustomContact contact, IEnumerable <ApiPaymentPlan> planList, DateTimeOffset currentDate)
{
contact.CheckNotNull(nameof(contact));
planList.CheckNotNull(nameof(planList));
var products = new List <ProcessOrderProduct>();
// Don't bill trials until something has been paid.
foreach (var plan in planList.Where(x => contact.HasPaidHealingTechnologies == true || x.PeriodUnit != PaymentPeriodUnit.MonthPostpaidTrial))
{
//var isTrialExpired = ((currentDate - (plan.StartDate ?? plan.DateAdded!.Value)).TotalDays > (plan.PeriodQty ?? _config.Value.DefaultTrialDays))
var qty = CalcPeriodQty(plan, currentDate);
if (qty > 0)
{
// Apply TransactionsLeft.
//var maxQty = plan.TransactionsLeft ?? (plan.PeriodUnit == PaymentPeriodUnit.MonthPostpaid || plan.PeriodUnit == PaymentPeriodUnit.MonthPostpaidTrial ? (int?)null : 1);
//if (maxQty != null && qty > maxQty)
//{
// qty = maxQty.Value;
//}
// Add product to cart.
var product = new ProcessOrderProduct(plan.ProductName ?? string.Empty);
if ((qty % 1) == 0)
{
product.Quantity = (int)qty;
product.Price = plan.PricePerPeriod ?? 0;
}
else
{
product.Quantity = 1;
product.Price = Math.Round((plan.PricePerPeriod ?? 0) * qty, 2);
}
products.Add(product);
}
}
return(products.GroupDuplicates());
}
