Fix minecarts not dropping chains on death

Author: zenfyrdev

src/main/java/com/github/vini2003/linkart/mixin/AbstractMinecartEntityMixin.java

@@ -36,7 +36,7 @@ public abstract class AbstractMinecartEntityMixin extends Entity implements Link
     @Unique
     private UUID linkart$followerUUID;
     @Unique
-    private ItemStack linkart$itemStack;
+    private ItemStack linkart$itemStack = ItemStack.EMPTY;
 
     public AbstractMinecartEntityMixin(EntityType<?> type, World world) {
         super(type, world);

src/main/java/com/github/vini2003/linkart/mixin/EntityMixin.java

@@ -4,10 +4,13 @@
 import com.github.vini2003.linkart.utility.CollisionUtils;
 import net.minecraft.block.AbstractRailBlock;
 import net.minecraft.entity.Entity;
+import net.minecraft.entity.ItemEntity;
 import net.minecraft.entity.vehicle.AbstractMinecartEntity;
+import net.minecraft.item.ItemStack;
 import net.minecraft.util.math.Box;
 import net.minecraft.util.math.Vec3d;
 import net.minecraft.world.World;
+import org.jetbrains.annotations.Nullable;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Shadow;
 import org.spongepowered.asm.mixin.injection.At;
@@ -25,6 +28,8 @@ public abstract class EntityMixin {
     @Shadow
     public abstract Box getBoundingBox();
 
+    @Shadow @Nullable public abstract ItemEntity dropStack(ItemStack stack);
+
     @Inject(at = @At("HEAD"), method = "remove")
     void linkart$removeLink(CallbackInfo callbackInformation) {
         if ((Entity) (Object) this instanceof AbstractMinecartEntity && !world.isClient()) {
@@ -55,4 +60,11 @@ public abstract class EntityMixin {
             }
         }
     }
+
+    @Inject(at = @At("HEAD"), method = "kill")
+    private void linkart$kill(CallbackInfo ci) {
+        if ((Object) this instanceof LinkableMinecart minecart) {
+            this.dropStack(minecart.linkart$getLinkItem());
+        }
+    }
 }