#776: Add ability to cancel ProjectileHitEvent

By: Martoph <sager1018@gmail.com>

paper-server/nms-patches/net/minecraft/world/entity/projectile/EntityArrow.patch

@@ -13,6 +13,15 @@
  public abstract class EntityArrow extends IProjectile {
  
      private static final DataWatcherObject<Byte> f = DataWatcher.a(EntityArrow.class, DataWatcherRegistry.a);
+@@ -181,7 +187,7 @@
+                 }
+ 
+                 if (object != null && !flag) {
+-                    this.a((MovingObjectPosition) object);
++                    this.preOnHit((MovingObjectPosition) object); // CraftBukkit - projectile hit event
+                     this.impulse = true;
+                 }
+ 
 @@ -328,7 +334,13 @@
          int k = entity.getFireTicks();
  

paper-server/nms-patches/net/minecraft/world/entity/projectile/EntityFireball.patch

@@ -29,10 +29,12 @@
          double d6 = (double) MathHelper.sqrt(d3 * d3 + d4 * d4 + d5 * d5);
  
          if (d6 != 0.0D) {
-@@ -64,6 +74,12 @@
+@@ -63,7 +73,13 @@
+             MovingObjectPosition movingobjectposition = ProjectileHelper.a((Entity) this, this::a);
  
              if (movingobjectposition.getType() != MovingObjectPosition.EnumMovingObjectType.MISS) {
-                 this.a(movingobjectposition);
+-                this.a(movingobjectposition);
++                this.preOnHit(movingobjectposition); // CraftBukkit - projectile hit event
 +
 +                // CraftBukkit start - Fire ProjectileHitEvent
 +                if (this.dead) {

paper-server/nms-patches/net/minecraft/world/entity/projectile/EntityFireworks.patch

@@ -9,6 +9,15 @@
  public class EntityFireworks extends IProjectile {
  
      public static final DataWatcherObject<ItemStack> FIREWORK_ITEM = DataWatcher.a(EntityFireworks.class, DataWatcherRegistry.g);
+@@ -130,7 +132,7 @@
+         MovingObjectPosition movingobjectposition = ProjectileHelper.a((Entity) this, this::a);
+ 
+         if (!this.noclip) {
+-            this.a(movingobjectposition);
++            this.preOnHit(movingobjectposition); // CraftBukkit - projectile hit event
+             this.impulse = true;
+         }
+ 
 @@ -145,7 +147,11 @@
          }
  

paper-server/nms-patches/net/minecraft/world/entity/projectile/EntityFishingHook.patch

@@ -26,6 +26,15 @@
      private EntityFishingHook(World world, EntityHuman entityhuman, int i, int j) {
          super(EntityTypes.FISHING_BOBBER, world);
          this.b = new Random();
+@@ -244,7 +256,7 @@
+     private void m() {
+         MovingObjectPosition movingobjectposition = ProjectileHelper.a((Entity) this, this::a);
+ 
+-        this.a(movingobjectposition);
++        this.preOnHit(movingobjectposition); // CraftBukkit - projectile hit event
+     }
+ 
+     @Override
 @@ -291,6 +303,10 @@
                  this.waitTime = 0;
                  this.ai = 0;

paper-server/nms-patches/net/minecraft/world/entity/projectile/EntityLlamaSpit.patch

@@ -0,0 +1,11 @@
+--- a/net/minecraft/world/entity/projectile/EntityLlamaSpit.java
++++ b/net/minecraft/world/entity/projectile/EntityLlamaSpit.java
+@@ -34,7 +34,7 @@
+         MovingObjectPosition movingobjectposition = ProjectileHelper.a((Entity) this, this::a);
+ 
+         if (movingobjectposition != null) {
+-            this.a(movingobjectposition);
++            this.preOnHit(movingobjectposition); // CraftBukkit - projectile hit event
+         }
+ 
+         double d0 = this.locX() + vec3d.x;

paper-server/nms-patches/net/minecraft/world/entity/projectile/EntityProjectile.patch

@@ -0,0 +1,11 @@
+--- a/net/minecraft/world/entity/projectile/EntityProjectile.java
++++ b/net/minecraft/world/entity/projectile/EntityProjectile.java
+@@ -57,7 +57,7 @@
+         }
+ 
+         if (movingobjectposition.getType() != MovingObjectPosition.EnumMovingObjectType.MISS && !flag) {
+-            this.a(movingobjectposition);
++            this.preOnHit(movingobjectposition); // CraftBukkit - projectile hit event
+         }
+ 
+         this.checkBlockCollisions();

paper-server/nms-patches/net/minecraft/world/entity/projectile/EntityShulkerBullet.patch

@@ -22,6 +22,15 @@
      @Override
      public SoundCategory getSoundCategory() {
          return SoundCategory.HOSTILE;
+@@ -218,7 +231,7 @@
+             MovingObjectPosition movingobjectposition = ProjectileHelper.a((Entity) this, this::a);
+ 
+             if (movingobjectposition.getType() != MovingObjectPosition.EnumMovingObjectType.MISS) {
+-                this.a(movingobjectposition);
++                this.preOnHit(movingobjectposition); // CraftBukkit - projectile hit event
+             }
+         }
+ 
 @@ -280,7 +293,7 @@
          if (flag) {
              this.a(entityliving, entity);

paper-server/nms-patches/net/minecraft/world/entity/projectile/IProjectile.patch

@@ -1,6 +1,6 @@
 --- a/net/minecraft/world/entity/projectile/IProjectile.java
 +++ b/net/minecraft/world/entity/projectile/IProjectile.java
-@@ -15,6 +15,10 @@
+@@ -15,12 +15,20 @@
  import net.minecraft.world.phys.MovingObjectPositionEntity;
  import net.minecraft.world.phys.Vec3D;
  
@@ -11,7 +11,17 @@
  public abstract class IProjectile extends Entity {
  
      private UUID shooter;
-@@ -30,6 +34,7 @@
+     private int c;
+     private boolean d;
+ 
++    // CraftBukkit start
++    private boolean hitCancelled = false;
++    // CraftBukkit end
++
+     IProjectile(EntityTypes<? extends IProjectile> entitytypes, World world) {
+         super(entitytypes, world);
+     }
+@@ -30,6 +38,7 @@
              this.shooter = entity.getUniqueID();
              this.c = entity.getId();
          }
@@ -19,11 +29,32 @@
  
      }
  
-@@ -112,6 +117,7 @@
+@@ -111,6 +120,16 @@
+         this.setMot(this.getMot().add(vec3d.x, entity.isOnGround() ? 0.0D : vec3d.y, vec3d.z));
      }
  
++    // CraftBukkit start - call projectile hit event
++    protected void preOnHit(MovingObjectPosition movingobjectposition) {
++        org.bukkit.event.entity.ProjectileHitEvent event = org.bukkit.craftbukkit.event.CraftEventFactory.callProjectileHitEvent(this, movingobjectposition);
++        this.hitCancelled = event != null && event.isCancelled();
++        if (movingobjectposition.getType() == MovingObjectPosition.EnumMovingObjectType.BLOCK || !this.hitCancelled) {
++            this.a(movingobjectposition); // PAIL rename onHit
++        }
++    }
++    // CraftBukkit end
++
      protected void a(MovingObjectPosition movingobjectposition) {
-+        org.bukkit.craftbukkit.event.CraftEventFactory.callProjectileHitEvent(this, movingobjectposition); // CraftBukkit - Call event
          MovingObjectPosition.EnumMovingObjectType movingobjectposition_enummovingobjecttype = movingobjectposition.getType();
  
-         if (movingobjectposition_enummovingobjecttype == MovingObjectPosition.EnumMovingObjectType.ENTITY) {
+@@ -125,6 +144,11 @@
+     protected void a(MovingObjectPositionEntity movingobjectpositionentity) {}
+ 
+     protected void a(MovingObjectPositionBlock movingobjectpositionblock) {
++        // CraftBukkit start - cancellable hit event
++        if (hitCancelled) {
++            return;
++        }
++        // CraftBukkit end
+         IBlockData iblockdata = this.world.getType(movingobjectpositionblock.getBlockPosition());
+ 
+         iblockdata.a(this.world, iblockdata, movingobjectpositionblock, this);

paper-server/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java

@@ -1167,9 +1167,9 @@ public class CraftEventFactory {
         return event;
     }
 
-    public static void callProjectileHitEvent(Entity entity, MovingObjectPosition position) {
+    public static ProjectileHitEvent callProjectileHitEvent(Entity entity, MovingObjectPosition position) {
         if (position.getType() == MovingObjectPosition.EnumMovingObjectType.MISS) {
-            return;
+            return null;
         }
 
         Block hitBlock = null;
@@ -1187,6 +1187,7 @@ public class CraftEventFactory {
 
         ProjectileHitEvent event = new ProjectileHitEvent((Projectile) entity.getBukkitEntity(), hitEntity, hitBlock, hitFace);
         entity.world.getServer().getPluginManager().callEvent(event);
+        return event;
     }
 
     public static ExpBottleEvent callExpBottleEvent(Entity entity, int exp) {