using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Data;
using System.Windows.Media.Imaging;
using Work;

namespace _29WxOrderWpf.Converters
{
    public class ImageUrlToBitmapImageConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value is string url && Uri.IsWellFormedUriString(url, UriKind.Absolute))
            {
                try
                {
                    // 直接加载绑定如果遇到有问题的网络图片会直接崩溃。
                    //var bitMap = new BitmapImage(new Uri(url));
                    BitmapImage bitMap = null;
                    //bitMap = LoadImageFromUrl(url + "?imageView2/1/w/100/format/webp|imageMogr2/auto-orient=");
                    bitMap = LoadImageFromUrl(url);
                    return bitMap;
                    //string errStr = "";
                    //var bitmapImg = GetUrlImg(url, out errStr);
                    //return bitmapImg;
                }
                catch
                {

                }
                //return Task.Run(() => new BitmapImage(new Uri(url))); // 使用 Task.Run 来异步加载图片。
            }
            return null;
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            throw new NotImplementedException(); // 不需要反向转换，所以不实现。
        }


        public static BitmapImage LoadImageFromUrl(string url)
        {
            BitmapImage bitmap = new BitmapImage();

            try
            {
                using (WebClient webClient = new WebClient())
                {
                    // 下载图片数据到内存流
                    using (MemoryStream stream = new MemoryStream(webClient.DownloadData(url)))
                    {
                        stream.Position = 0; // 重置流的位置到开始处
                        bitmap.BeginInit();
                        bitmap.CreateOptions = BitmapCreateOptions.PreservePixelFormat;
                        bitmap.CacheOption = BitmapCacheOption.OnLoad; // 或者使用 BitmapCacheOption.OnLoad 以减少内存使用
                        bitmap.UriSource = null; // 清除可能的旧UriSource，防止缓存问题
                        bitmap.StreamSource = stream;
                        bitmap.EndInit();
                        bitmap.Freeze(); // 防止后续更改，提高性能
                    }
                }
            }
            catch (Exception ex)
            {
                // 处理异常，例如打印错误信息或设置一个默认图片等
                //Console.WriteLine("Error loading image: " + ex.Message);
                return null;
            }

            return bitmap;
        }
    }
}