public async Task <IEnumerable <ProductDto> > GetSortedProductsAsync(ProductSortOptions sortOption)
{
var products = await client.GetProductsAsync();
if (sortOption != ProductSortOptions.Recommended)
{
var orderBy = SortOptionsToOrderBy(sortOption);
return(products.AsQueryable().OrderBy(orderBy));
}
var popularProducts = await GetShoppingHistories();
var productsList = products.ToList();
productsList.Sort((x, y) =>
{
double?xValue = null;
double?yValue = null;
if (popularProducts.ContainsKey(x.Name))
{
xValue = popularProducts[x.Name];
}
if (popularProducts.ContainsKey(y.Name))
{
yValue = popularProducts[y.Name];
}
if (xValue.HasValue && yValue.HasValue)
{
return(yValue.Value.CompareTo(xValue.Value));
}
if (xValue.HasValue)
{
return(-1);
}
if (yValue.HasValue)
{
return(1);
}
return(string.Compare(x.Name, y.Name, StringComparison.OrdinalIgnoreCase));
});
return(productsList);
}
private string SortOptionsToOrderBy(ProductSortOptions sortOptions)
{
switch (sortOptions)
{
case ProductSortOptions.Ascending:
return($"{nameof(ProductDto.Name)} ascending");
case ProductSortOptions.Descending:
return($"{nameof(ProductDto.Name)} descending");
case ProductSortOptions.High:
return($"{nameof(ProductDto.Price)} descending");
case ProductSortOptions.Low:
return($"{nameof(ProductDto.Price)} ascending");
case ProductSortOptions.Recommended:
throw new ArgumentException();
}
return(null);
}
