SPIGOT-7799, #1436: Expose explosion world interaction in EntityExplodeEvent and BlockExplodeEvent

By: antiPerson <nathat890@outlook.com>

paper-server/nms-patches/net/minecraft/world/entity/boss/enderdragon/EntityEnderDragon.patch

@@ -1,6 +1,6 @@
 --- a/net/minecraft/world/entity/boss/enderdragon/EntityEnderDragon.java
 +++ b/net/minecraft/world/entity/boss/enderdragon/EntityEnderDragon.java
-@@ -52,6 +52,20 @@
+@@ -52,6 +52,21 @@
  import net.minecraft.world.phys.Vec3D;
  import org.slf4j.Logger;
  
@@ -16,12 +16,13 @@
 +import org.bukkit.event.entity.EntityExplodeEvent;
 +import org.bukkit.event.entity.EntityRegainHealthEvent;
 +import org.bukkit.event.entity.EntityRemoveEvent;
++import org.bukkit.craftbukkit.event.CraftEventFactory;
 +// CraftBukkit end
 +
  public class EntityEnderDragon extends EntityInsentient implements IMonster {
  
      private static final Logger LOGGER = LogUtils.getLogger();
-@@ -89,6 +103,7 @@
+@@ -89,6 +104,7 @@
      private final PathPoint[] nodes;
      private final int[] nodeAdjacency;
      private final Path openSet;
@@ -29,7 +30,7 @@
  
      public EntityEnderDragon(EntityTypes<? extends EntityEnderDragon> entitytypes, World world) {
          super(EntityTypes.ENDER_DRAGON, world);
-@@ -110,6 +125,7 @@
+@@ -110,6 +126,7 @@
          this.noPhysics = true;
          this.noCulling = true;
          this.phaseManager = new DragonControllerManager(this);
@@ -37,7 +38,7 @@
      }
  
      public void setDragonFight(EnderDragonBattle enderdragonbattle) {
-@@ -257,7 +273,7 @@
+@@ -257,7 +274,7 @@
  
                      Vec3D vec3d1 = idragoncontroller.getFlyTargetLocation();
  
@@ -46,7 +47,7 @@
                          double d0 = vec3d1.x - this.getX();
                          double d1 = vec3d1.y - this.getY();
                          double d2 = vec3d1.z - this.getZ();
-@@ -404,7 +420,14 @@
+@@ -404,7 +421,14 @@
              if (this.nearestCrystal.isRemoved()) {
                  this.nearestCrystal = null;
              } else if (this.tickCount % 10 == 0 && this.getHealth() < this.getMaxHealth()) {
@@ -62,7 +63,7 @@
              }
          }
  
-@@ -489,6 +512,9 @@
+@@ -489,6 +513,9 @@
          int j1 = MathHelper.floor(axisalignedbb.maxZ);
          boolean flag = false;
          boolean flag1 = false;
@@ -72,7 +73,7 @@
  
          for (int k1 = i; k1 <= l; ++k1) {
              for (int l1 = j; l1 <= i1; ++l1) {
-@@ -498,7 +524,11 @@
+@@ -498,7 +525,11 @@
  
                      if (!iblockdata.isAir() && !iblockdata.is(TagsBlock.DRAGON_TRANSPARENT)) {
                          if (this.level().getGameRules().getBoolean(GameRules.RULE_MOBGRIEFING) && !iblockdata.is(TagsBlock.DRAGON_IMMUNE)) {
@@ -85,7 +86,7 @@
                          } else {
                              flag = true;
                          }
-@@ -507,6 +537,51 @@
+@@ -507,6 +538,49 @@
              }
          }
  
@@ -95,9 +96,7 @@
 +            return flag;
 +        }
 +
-+        org.bukkit.entity.Entity bukkitEntity = this.getBukkitEntity();
++        EntityExplodeEvent event = CraftEventFactory.callEntityExplodeEvent(this, destroyedBlocks, 0F, explosionSource.getBlockInteraction());
-+        EntityExplodeEvent event = new EntityExplodeEvent(bukkitEntity, bukkitEntity.getLocation(), destroyedBlocks, 0F);
-+        bukkitEntity.getServer().getPluginManager().callEvent(event);
 +        if (event.isCancelled()) {
 +            // This flag literally means 'Dragon hit something hard' (Obsidian, White Stone or Bedrock) and will cause the dragon to slow down.
 +            // We should consider adding an event extension for it, or perhaps returning true if the event is cancelled.
@@ -137,7 +136,7 @@
          if (flag1) {
              BlockPosition blockposition1 = new BlockPosition(i + this.random.nextInt(l - i + 1), j + this.random.nextInt(i1 - j + 1), k + this.random.nextInt(j1 - k + 1));
  
-@@ -562,7 +637,7 @@
+@@ -562,7 +636,7 @@
  
      @Override
      public void kill() {
@@ -146,7 +145,7 @@
          this.gameEvent(GameEvent.ENTITY_DIE);
          if (this.dragonFight != null) {
              this.dragonFight.updateDragon(this);
-@@ -571,6 +646,21 @@
+@@ -571,6 +645,21 @@
  
      }
  
@@ -168,7 +167,7 @@
      @Override
      protected void tickDeath() {
          if (this.dragonFight != null) {
-@@ -586,15 +676,20 @@
+@@ -586,15 +675,20 @@
              this.level().addParticle(Particles.EXPLOSION_EMITTER, this.getX() + (double) f, this.getY() + 2.0D + (double) f1, this.getZ() + (double) f2, 0.0D, 0.0D, 0.0D);
          }
  
@@ -190,7 +189,7 @@
                  EntityExperienceOrb.award((WorldServer) this.level(), this.position(), MathHelper.floor((float) short0 * 0.08F));
              }
  
-@@ -605,7 +700,7 @@
+@@ -605,7 +699,7 @@
  
          this.move(EnumMoveType.SELF, new Vec3D(0.0D, 0.10000000149011612D, 0.0D));
          if (this.dragonDeathTime == 200 && this.level() instanceof WorldServer) {
@@ -199,7 +198,7 @@
                  EntityExperienceOrb.award((WorldServer) this.level(), this.position(), MathHelper.floor((float) short0 * 0.2F));
              }
  
-@@ -613,7 +708,7 @@
+@@ -613,7 +707,7 @@
                  this.dragonFight.setDragonKilled(this);
              }
  
@@ -208,7 +207,7 @@
              this.gameEvent(GameEvent.ENTITY_DIE);
          }
  
-@@ -826,6 +921,7 @@
+@@ -826,6 +920,7 @@
          super.addAdditionalSaveData(nbttagcompound);
          nbttagcompound.putInt("DragonPhase", this.phaseManager.getCurrentPhase().getPhase().getId());
          nbttagcompound.putInt("DragonDeathTime", this.dragonDeathTime);
@@ -216,7 +215,7 @@
      }
  
      @Override
-@@ -839,6 +935,11 @@
+@@ -839,6 +934,11 @@
              this.dragonDeathTime = nbttagcompound.getInt("DragonDeathTime");
          }
  

paper-server/nms-patches/net/minecraft/world/level/Explosion.patch

@@ -112,13 +112,12 @@
                          entity.setDeltaMovement(entity.getDeltaMovement().add(vec3d1));
                          if (entity instanceof EntityHuman) {
                              EntityHuman entityhuman = (EntityHuman) entity;
-@@ -291,9 +350,65 @@
+@@ -291,9 +350,62 @@
  
              SystemUtils.shuffle(this.toBlow, this.level.random);
              ObjectListIterator objectlistiterator = this.toBlow.iterator();
 +            // CraftBukkit start
 +            org.bukkit.World bworld = this.level.getWorld();
-+            org.bukkit.entity.Entity explode = this.source == null ? null : this.source.getBukkitEntity();
 +            Location location = new Location(bworld, this.x, this.y, this.z);
 +
 +            List<org.bukkit.block.Block> blockList = new ObjectArrayList<>();
@@ -132,17 +131,15 @@
 +
 +            List<org.bukkit.block.Block> bukkitBlocks;
 +
-+            if (explode != null) {
++            if (this.source != null) {
-+                EntityExplodeEvent event = new EntityExplodeEvent(explode, location, blockList, this.yield);
++                EntityExplodeEvent event = CraftEventFactory.callEntityExplodeEvent(this.source, blockList, this.yield, getBlockInteraction());
-+                this.level.getCraftServer().getPluginManager().callEvent(event);
 +                this.wasCanceled = event.isCancelled();
 +                bukkitBlocks = event.blockList();
 +                this.yield = event.getYield();
 +            } else {
 +                org.bukkit.block.Block block = location.getBlock();
 +                org.bukkit.block.BlockState blockState = (damageSource.getDirectBlockState() != null) ? damageSource.getDirectBlockState() : block.getState();
-+                BlockExplodeEvent event = new BlockExplodeEvent(block, blockState, blockList, this.yield);
++                BlockExplodeEvent event = CraftEventFactory.callBlockExplodeEvent(block, blockState, blockList, this.yield, getBlockInteraction());
-+                this.level.getCraftServer().getPluginManager().callEvent(event);
 +                this.wasCanceled = event.isCancelled();
 +                bukkitBlocks = event.blockList();
 +                this.yield = event.getYield();
@@ -178,7 +175,7 @@
  
                  this.level.getBlockState(blockposition).onExplosionHit(this.level, blockposition, this, (itemstack, blockposition1) -> {
                      addOrAppendStack(list, itemstack, blockposition1);
-@@ -318,7 +433,11 @@
+@@ -318,7 +430,11 @@
                  BlockPosition blockposition1 = (BlockPosition) objectlistiterator1.next();
  
                  if (this.random.nextInt(3) == 0 && this.level.getBlockState(blockposition1).isAir() && this.level.getBlockState(blockposition1.below()).isSolidRender(this.level, blockposition1.below())) {
@@ -191,7 +188,7 @@
                  }
              }
          }
-@@ -326,6 +445,7 @@
+@@ -326,6 +442,7 @@
      }
  
      private static void addOrAppendStack(List<Pair<ItemStack, BlockPosition>> list, ItemStack itemstack, BlockPosition blockposition) {

paper-server/src/main/java/org/bukkit/craftbukkit/CraftExplosionResult.java

@@ -0,0 +1,27 @@
+package org.bukkit.craftbukkit;
+
+import com.google.common.base.Preconditions;
+import net.minecraft.world.level.Explosion;
+import org.bukkit.ExplosionResult;
+
+public final class CraftExplosionResult {
+
+    private CraftExplosionResult() {}
+
+    public static ExplosionResult toBukkit(Explosion.Effect effect) {
+        Preconditions.checkArgument(effect != null, "explosion effect cannot be null");
+
+        switch (effect) {
+            case KEEP:
+                return ExplosionResult.KEEP;
+            case DESTROY:
+                return ExplosionResult.DESTROY;
+            case DESTROY_WITH_DECAY:
+                return ExplosionResult.DESTROY_WITH_DECAY;
+            case TRIGGER_BLOCK:
+                return ExplosionResult.TRIGGER_BLOCK;
+            default:
+                throw new IllegalArgumentException("There is no ExplosionResult which matches " + effect);
+        }
+    }
+}

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

@@ -86,6 +86,7 @@ import org.bukkit.block.Sign;
 import org.bukkit.block.sign.Side;
 import org.bukkit.craftbukkit.CraftChunk;
 import org.bukkit.craftbukkit.CraftEquipmentSlot;
+import org.bukkit.craftbukkit.CraftExplosionResult;
 import org.bukkit.craftbukkit.CraftLootTable;
 import org.bukkit.craftbukkit.CraftRaid;
 import org.bukkit.craftbukkit.CraftServer;
@@ -143,6 +144,7 @@ import org.bukkit.event.block.BellRingEvent;
 import org.bukkit.event.block.BlockDamageAbortEvent;
 import org.bukkit.event.block.BlockDamageEvent;
 import org.bukkit.event.block.BlockDropItemEvent;
+import org.bukkit.event.block.BlockExplodeEvent;
 import org.bukkit.event.block.BlockFadeEvent;
 import org.bukkit.event.block.BlockFormEvent;
 import org.bukkit.event.block.BlockGrowEvent;
@@ -176,6 +178,7 @@ import org.bukkit.event.entity.EntityDamageEvent.DamageModifier;
 import org.bukkit.event.entity.EntityDeathEvent;
 import org.bukkit.event.entity.EntityEnterLoveModeEvent;
 import org.bukkit.event.entity.EntityExhaustionEvent;
+import org.bukkit.event.entity.EntityExplodeEvent;
 import org.bukkit.event.entity.EntityInteractEvent;
 import org.bukkit.event.entity.EntityKnockbackByEntityEvent;
 import org.bukkit.event.entity.EntityKnockbackEvent;
@@ -1835,6 +1838,18 @@ public class CraftEventFactory {
         return !event.isCancelled();
     }
 
+    public static EntityExplodeEvent callEntityExplodeEvent(Entity entity, List<Block> blocks, float yield, Explosion.Effect effect) {
+        EntityExplodeEvent event = new EntityExplodeEvent(entity.getBukkitEntity(), entity.getBukkitEntity().getLocation(), blocks, yield, CraftExplosionResult.toBukkit(effect));
+        Bukkit.getPluginManager().callEvent(event);
+        return event;
+    }
+
+    public static BlockExplodeEvent callBlockExplodeEvent(Block block, BlockState state, List<Block> blocks, float yield, Explosion.Effect effect) {
+        BlockExplodeEvent event = new BlockExplodeEvent(block, state, blocks, yield, CraftExplosionResult.toBukkit(effect));
+        Bukkit.getPluginManager().callEvent(event);
+        return event;
+    }
+
     public static ExplosionPrimeEvent callExplosionPrimeEvent(Explosive explosive) {
         ExplosionPrimeEvent event = new ExplosionPrimeEvent(explosive);
         Bukkit.getPluginManager().callEvent(event);

paper-server/src/test/java/org/bukkit/ExplosionResultTest.java

@@ -0,0 +1,23 @@
+package org.bukkit;
+
+import static org.junit.jupiter.api.Assertions.*;
+import net.minecraft.world.level.Explosion;
+import org.bukkit.craftbukkit.CraftExplosionResult;
+import org.junit.jupiter.api.Test;
+
+public class ExplosionResultTest {
+
+    @Test
+    public void testMatchingEnum() {
+        for (ExplosionResult result : ExplosionResult.values()) {
+            assertNotNull(Explosion.Effect.valueOf(result.name()), "No NMS enum for Bukkit result " + result);
+        }
+    }
+
+    @Test
+    public void testToBukkit() {
+        for (Explosion.Effect effect : Explosion.Effect.values()) {
+            assertNotNull(CraftExplosionResult.toBukkit(effect), "No Bukkit enum for NMS explosion effect " + effect);
+        }
+    }
+}