[Bleeding] Handle custom furnace recipes separately. Fixes BUKKIT-1657, BUKKIT-3846

Due to vanilla blanket comparing data values, and the unspecified
order of hashmap iterators, we need to run through custom recipes
first, and therefore separately, to ensure that they are actually
used. By not adding the custom results to the experience table, we do
not override the experience gains from vanilla smelting recipes.

src/main/java/net/minecraft/server/RecipesFurnace.java

@@ -10,6 +10,7 @@ public class RecipesFurnace {
     private static final RecipesFurnace a = new RecipesFurnace();
     public Map recipes = new HashMap(); // CraftBukkit - private -> public
     private Map c = new HashMap();
+    public Map customRecipes = new HashMap(); // CraftBukkit
 
     public static RecipesFurnace getInstance() {
         return a;
@@ -62,15 +63,31 @@ public class RecipesFurnace {
         this.c.put(itemstack1, Float.valueOf(f));
     }
 
+    // CraftBukkit start
+    public void registerRecipe(ItemStack itemstack, ItemStack itemstack1) {
+        this.customRecipes.put(itemstack, itemstack1);
+    }
+    // CraftBukkit end
+
     public ItemStack getResult(ItemStack itemstack) {
-        Iterator iterator = this.recipes.entrySet().iterator();
+        // CraftBukkit start
+        boolean vanilla = false;
+        Iterator iterator = this.customRecipes.entrySet().iterator();
+        // CraftBukkit end
 
         Entry entry;
 
         do {
             if (!iterator.hasNext()) {
+                // CraftBukkit start
+                if (!vanilla) {
+                    iterator = this.recipes.entrySet().iterator();
+                    vanilla = true;
+                } else {
                     return null;
                 }
+                // CraftBukkit end
+            }
 
             entry = (Entry) iterator.next();
         } while (!this.a(itemstack, (ItemStack) entry.getKey()));

src/main/java/org/bukkit/craftbukkit/CraftServer.java

@@ -961,11 +961,13 @@ public final class CraftServer implements Server {
     public void clearRecipes() {
         CraftingManager.getInstance().recipes.clear();
         RecipesFurnace.getInstance().recipes.clear();
+        RecipesFurnace.getInstance().customRecipes.clear();
     }
 
     public void resetRecipes() {
         CraftingManager.getInstance().recipes = new CraftingManager().recipes;
         RecipesFurnace.getInstance().recipes = new RecipesFurnace().recipes;
+        RecipesFurnace.getInstance().customRecipes.clear();
     }
 
     public Map<String, String[]> getCommandAliases() {

src/main/java/org/bukkit/craftbukkit/inventory/CraftFurnaceRecipe.java

@@ -22,6 +22,6 @@ public class CraftFurnaceRecipe extends FurnaceRecipe implements CraftRecipe {
     public void addToCraftingManager() {
         ItemStack result = this.getResult();
         ItemStack input = this.getInput();
-        RecipesFurnace.getInstance().a(CraftMagicNumbers.getItem(input.getTypeId()), CraftItemStack.asNMSCopy(result), 0.1f);
+        RecipesFurnace.getInstance().registerRecipe(CraftItemStack.asNMSCopy(input), CraftItemStack.asNMSCopy(result));
     }
 }