using System.Threading;
using System.Threading.Tasks;
using System.Windows.Media;

namespace OrderSupportTicket.Services;

/// <summary>
/// 商品缩略图加载器，限制并发下载数量，避免工单列表同时发起大量请求。
/// </summary>
internal static class ProductImageLoader
{
    private static readonly SemaphoreSlim Gate = new SemaphoreSlim(4, 4);

    public static async Task<ImageSource> LoadAsync(string url)
    {
        if (string.IsNullOrWhiteSpace(url))
            return null;

        await Gate.WaitAsync().ConfigureAwait(false);
        try
        {
            return await Task.Run(
                () => AllBase.ImageBuild.LoadBitmipImageFromUrl(url.Trim()))
                .ConfigureAwait(false);
        }
        catch
        {
            return null;
        }
        finally
        {
            Gate.Release();
        }
    }
}