From 7a2f486768afeb6a54c39b19079e9f31f3adad1a Mon Sep 17 00:00:00 2001
From: Parker Hawke <hawkeboyz2@hotmail.com>
Date: Sat, 29 Sep 2018 19:24:51 -0400
Subject: [PATCH] Implement PlayerRecipeDiscoverEvent and methods to
 (un/)discover recipes

---
 nms-patches/RecipeBookServer.patch            | 19 +++++++++
 .../craftbukkit/entity/CraftHumanEntity.java  | 41 +++++++++++++++++++
 .../craftbukkit/event/CraftEventFactory.java  |  7 ++++
 3 files changed, 67 insertions(+)
 create mode 100644 nms-patches/RecipeBookServer.patch

diff --git a/nms-patches/RecipeBookServer.patch b/nms-patches/RecipeBookServer.patch
new file mode 100644
index 0000000000..3d60bc7944
--- /dev/null
+++ b/nms-patches/RecipeBookServer.patch
@@ -0,0 +1,19 @@
+--- a/net/minecraft/server/RecipeBookServer.java
++++ b/net/minecraft/server/RecipeBookServer.java
+@@ -8,6 +8,7 @@
+ import java.util.List;
+ import org.apache.logging.log4j.LogManager;
+ import org.apache.logging.log4j.Logger;
++import org.bukkit.craftbukkit.event.CraftEventFactory; // CraftBukkit
+ 
+ public class RecipeBookServer extends RecipeBook {
+ 
+@@ -27,7 +28,7 @@
+             IRecipe irecipe = (IRecipe) iterator.next();
+             MinecraftKey minecraftkey = irecipe.getKey();
+ 
+-            if (!this.a.contains(minecraftkey) && !irecipe.c()) {
++            if (!this.a.contains(minecraftkey) && !irecipe.c() && CraftEventFactory.handlePlayerRecipeListUpdateEvent(entityplayer, minecraftkey)) { // CraftBukkit
+                 this.a(minecraftkey);
+                 this.c(minecraftkey);
+                 arraylist.add(minecraftkey);
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftHumanEntity.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftHumanEntity.java
index 289e267bdd..497783d4f3 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftHumanEntity.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftHumanEntity.java
@@ -1,6 +1,9 @@
 package org.bukkit.craftbukkit.entity;
 
 import com.google.common.base.Preconditions;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
 import java.util.Set;
 
 import net.minecraft.server.*;
@@ -10,6 +13,7 @@ import org.bukkit.Location;
 import org.bukkit.inventory.MainHand;
 import org.bukkit.inventory.Merchant;
 import org.bukkit.Material;
+import org.bukkit.NamespacedKey;
 import org.bukkit.entity.HumanEntity;
 import org.bukkit.entity.Villager;
 import org.bukkit.event.inventory.InventoryType;
@@ -27,6 +31,7 @@ import org.bukkit.craftbukkit.inventory.CraftItemStack;
 import org.bukkit.craftbukkit.inventory.CraftMerchant;
 import org.bukkit.craftbukkit.CraftServer;
 import org.bukkit.craftbukkit.util.CraftMagicNumbers;
+import org.bukkit.craftbukkit.util.CraftNamespacedKey;
 import org.bukkit.inventory.EntityEquipment;
 import org.bukkit.permissions.PermissibleBase;
 import org.bukkit.permissions.Permission;
@@ -455,6 +460,42 @@ public class CraftHumanEntity extends CraftLivingEntity implements HumanEntity {
         getHandle().getCooldownTracker().a(CraftMagicNumbers.getItem(material), ticks);
     }
 
+    @Override
+    public boolean discoverRecipe(NamespacedKey recipe) {
+        return discoverRecipes(Arrays.asList(recipe)) != 0;
+    }
+
+    @Override
+    public int discoverRecipes(Collection<NamespacedKey> recipes) {
+        return getHandle().a(bukkitKeysToMinecraftRecipes(recipes)); // PAIL rename discoverRecipes
+    }
+
+    @Override
+    public boolean undiscoverRecipe(NamespacedKey recipe) {
+        return undiscoverRecipes(Arrays.asList(recipe)) != 0;
+    }
+
+    @Override
+    public int undiscoverRecipes(Collection<NamespacedKey> recipes) {
+        return getHandle().b(bukkitKeysToMinecraftRecipes(recipes)); // PAIL rename undiscoverRecipes
+    }
+
+    private Collection<IRecipe> bukkitKeysToMinecraftRecipes(Collection<NamespacedKey> recipeKeys) {
+        Collection<IRecipe> recipes = new ArrayList<>();
+        CraftingManager manager = getHandle().world.getMinecraftServer().getCraftingManager();
+
+        for (NamespacedKey recipeKey : recipeKeys) {
+            IRecipe recipe = manager.a(CraftNamespacedKey.toMinecraft(recipeKey));
+            if (recipe == null) {
+                continue;
+            }
+
+            recipes.add(recipe);
+        }
+
+        return recipes;
+    }
+
     @Override
     public org.bukkit.entity.Entity getShoulderEntityLeft() {
         if (!getHandle().getShoulderEntityLeft().isEmpty()) {
diff --git a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
index deb166d787..67d2eb1b63 100644
--- a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
+++ b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
@@ -34,6 +34,7 @@ import org.bukkit.craftbukkit.inventory.CraftMetaBook;
 import org.bukkit.craftbukkit.potion.CraftPotionUtil;
 import org.bukkit.craftbukkit.util.CraftDamageSource;
 import org.bukkit.craftbukkit.util.CraftMagicNumbers;
+import org.bukkit.craftbukkit.util.CraftNamespacedKey;
 import org.bukkit.entity.AreaEffectCloud;
 import org.bukkit.entity.Arrow;
 import org.bukkit.entity.Bat;
@@ -1129,4 +1130,10 @@ public class CraftEventFactory {
         Bukkit.getPluginManager().callEvent(event);
         return !event.isCancelled();
     }
+
+    public static boolean handlePlayerRecipeListUpdateEvent(EntityHuman who, MinecraftKey recipe) {
+        PlayerRecipeDiscoverEvent event = new PlayerRecipeDiscoverEvent((Player) who.getBukkitEntity(), CraftNamespacedKey.fromMinecraft(recipe));
+        Bukkit.getPluginManager().callEvent(event);
+        return !event.isCancelled();
+    }
 }