minecraft-kajetans-mod/src/main/java/me/km/overrides/PlayerCapeLoader.java

package me.km.overrides;

import java.net.HttpURLConnection;
import java.net.URL;
import java.util.HashMap;
import java.util.UUID;
import java.util.function.Consumer;
import net.minecraft.client.Minecraft;
import net.minecraft.client.renderer.texture.DynamicTexture;
import net.minecraft.client.renderer.texture.NativeImage;
import net.minecraft.client.renderer.texture.TextureManager;
import net.minecraft.util.ResourceLocation;
import net.minecraftforge.api.distmarker.Dist;
import net.minecraftforge.api.distmarker.OnlyIn;
import org.apache.logging.log4j.LogManager;

@OnlyIn(Dist.CLIENT)
public class PlayerCapeLoader
{
    private static class Data
    {
        private ResourceLocation cape;
    }

    public final static PlayerCapeLoader INSTANCE = new PlayerCapeLoader();

    private final HashMap<UUID, Data> skins = new HashMap<>();

    private final TextureManager manager = Minecraft.getInstance().getRenderManager().textureManager;

    private PlayerCapeLoader()
    {
    }

    public ResourceLocation getTexture(UUID uuid)
    {
        Data oldData = skins.get(uuid);
        if(oldData != null)
        {
            return oldData.cape;
        }
        Data newData = new Data();
        skins.put(uuid, newData);
        downloadCape(uuid, image ->
        {
            newData.cape = manager.getDynamicTextureLocation("cape_" + uuid, new DynamicTexture(image));
        });
        return null;
    }

    private void downloadCape(UUID uuid, Consumer<NativeImage> delayed)
    {
        new Thread(() ->
        {
            HttpURLConnection httpurlconnection = null;
            try
            {
                org.apache.logging.log4j.LogManager.getLogger().warn(String.format("http://skins.hammerle.me/cape_%s.png", uuid));
                httpurlconnection = (HttpURLConnection) (new URL("http://skins.hammerle.me/cape.png"))
                        .openConnection(Minecraft.getInstance().getProxy());
                httpurlconnection.setDoInput(true);
                httpurlconnection.setDoOutput(false);
                httpurlconnection.connect();

                int code = httpurlconnection.getResponseCode();
                if(code != 200)
                {
                    return;
                }

                NativeImage image = NativeImage.read(httpurlconnection.getInputStream());
                Minecraft.getInstance().enqueue(() -> delayed.accept(image));
            }
            catch(Exception ex)
            {
                LogManager.getLogger().warn("Error occurred when downloading skin, however, skin servers seem to be up.");
            }
            finally
            {
                if(httpurlconnection != null)
                {
                    httpurlconnection.disconnect();
                }
            }
        }).start();
    }
}