Paper/patches/server/0860-More-Projectile-API.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Owen1212055 <23108066+Owen1212055@users.noreply.github.com>
Date: Tue, 22 Jun 2021 23:41:11 -0400
Subject: [PATCH] More Projectile API

Co-authored-by: Nassim Jahnke <nassim@njahnke.dev>

diff --git a/src/main/java/net/minecraft/world/entity/projectile/ThrownPotion.java b/src/main/java/net/minecraft/world/entity/projectile/ThrownPotion.java
index fee09e6ff72cf1da389d5811dd005642cd50a5b4..4f276b2a86735a2c664738450ae0fbdd82031d4e 100644
--- a/src/main/java/net/minecraft/world/entity/projectile/ThrownPotion.java
+++ b/src/main/java/net/minecraft/world/entity/projectile/ThrownPotion.java
@@ -98,6 +98,11 @@ public class ThrownPotion extends ThrowableItemProjectile implements ItemSupplie
     @Override
     protected void onHit(HitResult hitResult) {
         super.onHit(hitResult);
+        // Paper start - More projectile API
+        this.splash(hitResult);
+    }
+    public void splash(@org.jetbrains.annotations.Nullable HitResult hitResult) {
+        // Paper end - More projectile API
         if (!this.level.isClientSide) {
             ItemStack itemstack = this.getItem();
             Potion potionregistry = PotionUtils.getPotion(itemstack);
@@ -110,7 +115,7 @@ public class ThrownPotion extends ThrowableItemProjectile implements ItemSupplie
                 if (this.isLingering()) {
                     this.makeAreaOfEffectCloud(itemstack, potionregistry);
                 } else {
-                    this.applySplash(list, hitResult.getType() == HitResult.Type.ENTITY ? ((EntityHitResult) hitResult).getEntity() : null);
+                    this.applySplash(list, hitResult != null && hitResult.getType() == HitResult.Type.ENTITY ? ((EntityHitResult) hitResult).getEntity() : null); // Paper - nullable hitResult
                 }
             }
 
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftFirework.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftFirework.java
index c242f654c88ca1773429348939d3bb2ffae3768c..d1c7ab67cba881d96b7a5e9220130d86d0514304 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftFirework.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftFirework.java
@@ -16,24 +16,26 @@ import org.bukkit.inventory.meta.FireworkMeta;
 public class CraftFirework extends CraftProjectile implements Firework {
 
     private final Random random = new Random();
-    private final CraftItemStack item;
+    //private CraftItemStack item; // Paper - Remove usage, not accurate representation of current item.
 
     public CraftFirework(CraftServer server, FireworkRocketEntity entity) {
         super(server, entity);
 
-        ItemStack item = this.getHandle().getEntityData().get(FireworkRocketEntity.DATA_ID_FIREWORKS_ITEM);
-
-        if (item.isEmpty()) {
-            item = new ItemStack(Items.FIREWORK_ROCKET);
-            this.getHandle().getEntityData().set(FireworkRocketEntity.DATA_ID_FIREWORKS_ITEM, item);
-        }
-
-        this.item = CraftItemStack.asCraftMirror(item);
-
-        // Ensure the item is a firework...
-        if (this.item.getType() != Material.FIREWORK_ROCKET) {
-            this.item.setType(Material.FIREWORK_ROCKET);
-        }
+//        Paper Start - Expose firework item directly
+//        ItemStack item = this.getHandle().getEntityData().get(FireworkRocketEntity.DATA_ID_FIREWORKS_ITEM);
+//
+//        if (item.isEmpty()) {
+//            item = new ItemStack(Items.FIREWORK_ROCKET);
+//            this.getHandle().getEntityData().set(FireworkRocketEntity.DATA_ID_FIREWORKS_ITEM, item);
+//        }
+//
+//        this.item = CraftItemStack.asCraftMirror(item);
+//
+//        // Ensure the item is a firework...
+//        if (this.item.getType() != Material.FIREWORK_ROCKET) {
+//            this.item.setType(Material.FIREWORK_ROCKET);
+//        }
+        // Paper End - Expose firework item directly
     }
 
     @Override
@@ -53,12 +55,12 @@ public class CraftFirework extends CraftProjectile implements Firework {
 
     @Override
     public FireworkMeta getFireworkMeta() {
-        return (FireworkMeta) this.item.getItemMeta();
+        return (FireworkMeta) CraftItemStack.getItemMeta(this.getHandle().getEntityData().get(FireworkRocketEntity.DATA_ID_FIREWORKS_ITEM), Material.FIREWORK_ROCKET); // Paper - Expose firework item directly
     }
 
     @Override
     public void setFireworkMeta(FireworkMeta meta) {
-        this.item.setItemMeta(meta);
+        applyFireworkEffect(meta); // Paper - Expose firework item directly
 
         // Copied from EntityFireworks constructor, update firework lifetime/power
         this.getHandle().lifetime = 10 * (1 + meta.getPower()) + this.random.nextInt(6) + this.random.nextInt(7);
@@ -142,4 +144,46 @@ public class CraftFirework extends CraftProjectile implements Firework {
         return getHandle().spawningEntity;
     }
     // Paper end
+    // Paper start - Expose firework item directly + manually setting flight
+    @Override
+    public org.bukkit.inventory.ItemStack getItem() {
+        return CraftItemStack.asBukkitCopy(this.getHandle().getItem());
+    }
+
+    @Override
+    public void setItem(org.bukkit.inventory.ItemStack itemStack) {
+        FireworkMeta meta = getFireworkMeta();
+        ItemStack nmsItem = itemStack == null ? ItemStack.EMPTY : CraftItemStack.asNMSCopy(itemStack);
+        this.getHandle().getEntityData().set(FireworkRocketEntity.DATA_ID_FIREWORKS_ITEM, nmsItem);
+
+        applyFireworkEffect(meta);
+    }
+
+    @Override
+    public int getTicksFlown() {
+        return this.getHandle().life;
+    }
+
+    @Override
+    public void setTicksFlown(int ticks) {
+        this.getHandle().life = ticks;
+    }
+
+    @Override
+    public int getTicksToDetonate() {
+        return this.getHandle().lifetime;
+    }
+
+    @Override
+    public void setTicksToDetonate(int ticks) {
+        this.getHandle().lifetime = ticks;
+    }
+
+    void applyFireworkEffect(FireworkMeta meta) {
+        ItemStack item = this.getHandle().getItem();
+        CraftItemStack.applyMetaToItem(item, meta);
+
+        this.getHandle().getEntityData().set(FireworkRocketEntity.DATA_ID_FIREWORKS_ITEM, item);
+    }
+    // Paper end - Expose firework item directly + manually setting flight
 }
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftFishHook.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftFishHook.java
index 6bfa984781a483d048ef4318761203c701d8a632..5e0c2c5094e1578162d1a50d50701fbd25e6d961 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftFishHook.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftFishHook.java
@@ -119,4 +119,15 @@ public class CraftFishHook extends CraftProjectile implements FishHook {
     public HookState getState() {
         return HookState.values()[this.getHandle().currentState.ordinal()];
     }
+    // Paper start - More FishHook API
+    @Override
+    public int getWaitTime() {
+        return this.getHandle().timeUntilLured;
+    }
+
+    @Override
+    public void setWaitTime(int ticks) {
+        this.getHandle().timeUntilLured = ticks;
+    }
+    // Paper end
 }
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftThrownPotion.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftThrownPotion.java
index 0db8aa840ea026d48215ac5dc80ffde5f12725b1..397e0df15a0e64e5bc522f62f3b327a5039ec4c8 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftThrownPotion.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftThrownPotion.java
@@ -39,11 +39,31 @@ public class CraftThrownPotion extends CraftThrowableProjectile implements Throw
         Validate.notNull(item, "ItemStack cannot be null.");
 
         // The ItemStack must be a potion.
-        Validate.isTrue(item.getType() == Material.LINGERING_POTION || item.getType() == Material.SPLASH_POTION, "ItemStack must be a lingering or splash potion. This item stack was " + item.getType() + ".");
+        //Validate.isTrue(item.getType() == Material.LINGERING_POTION || item.getType() == Material.SPLASH_POTION, "ItemStack must be a lingering or splash potion. This item stack was " + item.getType() + "."); // Paper - Projectile API
+        org.bukkit.inventory.meta.PotionMeta meta = (item.getType() == Material.LINGERING_POTION || item.getType() == Material.SPLASH_POTION) ? null : this.getPotionMeta(); // Paper - Projectile API
 
         this.getHandle().setItem(CraftItemStack.asNMSCopy(item));
+        if (meta != null) this.setPotionMeta(meta); // Paper - Projectile API
     }
 
+    // Paper start - Projectile API
+    @Override
+    public org.bukkit.inventory.meta.PotionMeta getPotionMeta() {
+        return (org.bukkit.inventory.meta.PotionMeta) CraftItemStack.getItemMeta(this.getHandle().getItemRaw(), Material.SPLASH_POTION);
+    }
+
+    @Override
+    public void setPotionMeta(org.bukkit.inventory.meta.PotionMeta meta) {
+        net.minecraft.world.item.ItemStack item = this.getHandle().getItem();
+        CraftItemStack.applyMetaToItem(item, meta);
+        this.getHandle().setItem(item); // Reset item
+    }
+
+    @Override
+    public void splash() {
+        this.getHandle().splash(null);
+    }
+    // Paper end
     @Override
     public net.minecraft.world.entity.projectile.ThrownPotion getHandle() {
         return (net.minecraft.world.entity.projectile.ThrownPotion) entity;
diff --git a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java b/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
index 04aabec62f0c89e70681af3846d73659f4c81360..c7c5f18cde7a4ad4dd821e452de3068c2e2187d1 100644
--- a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
+++ b/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
@@ -274,12 +274,20 @@ public final class CraftItemStack extends ItemStack {
     public ItemMeta getItemMeta() {
         return CraftItemStack.getItemMeta(this.handle);
     }
+    // Paper start
+    public static void applyMetaToItem(net.minecraft.world.item.ItemStack itemStack, ItemMeta meta) {
+        ((org.bukkit.craftbukkit.inventory.CraftMetaItem) meta).applyToItem(itemStack.getOrCreateTag());
+    }
 
     public static ItemMeta getItemMeta(net.minecraft.world.item.ItemStack item) {
+        return getItemMeta(item, CraftItemStack.getType(item));
+    }
+    public static ItemMeta getItemMeta(net.minecraft.world.item.ItemStack item, Material material) {
+        // Paper end
         if (!CraftItemStack.hasItemMeta(item)) {
-            return CraftItemFactory.instance().getItemMeta(CraftItemStack.getType(item));
+            return CraftItemFactory.instance().getItemMeta(material); // Paper
         }
-        switch (CraftItemStack.getType(item)) {
+        switch (material) {  // Paper
             case WRITTEN_BOOK:
                 return new CraftMetaBookSigned(item.getTag());
             case WRITABLE_BOOK: