SPIGOT-4570: Add FluidLevelChangeEvent

nms-patches/FluidTypeFlowing.patch

@@ -1,18 +1,21 @@
 --- a/net/minecraft/server/FluidTypeFlowing.java
 +++ b/net/minecraft/server/FluidTypeFlowing.java
-@@ -10,6 +10,11 @@
+@@ -10,6 +10,14 @@
  import java.util.Iterator;
  import java.util.Map;
  import java.util.Map.Entry;
 +// CraftBukkit start
 +import org.bukkit.block.BlockFace;
 +import org.bukkit.craftbukkit.block.CraftBlock;
++import org.bukkit.craftbukkit.block.data.CraftBlockData;
++import org.bukkit.craftbukkit.event.CraftEventFactory;
 +import org.bukkit.event.block.BlockFromToEvent;
++import org.bukkit.event.block.FluidLevelChangeEvent;
 +// CraftBukkit end
  
  public abstract class FluidTypeFlowing extends FluidType {
  
-@@ -141,6 +146,15 @@
+@@ -141,6 +149,15 @@
              Fluid fluid1 = this.a((IWorldReader) generatoraccess, blockposition1, iblockdata1);
  
              if (this.a(generatoraccess, blockposition, iblockdata, EnumDirection.DOWN, blockposition1, iblockdata1, generatoraccess.getFluid(blockposition1), fluid1.c())) {
@@ -28,7 +31,7 @@
                  this.a(generatoraccess, blockposition1, iblockdata1, EnumDirection.DOWN, fluid1);
                  if (this.a((IWorldReader) generatoraccess, blockposition) >= 3) {
                      this.a(generatoraccess, blockposition, fluid, iblockdata);
-@@ -171,6 +185,15 @@
+@@ -171,6 +188,15 @@
                  IBlockData iblockdata1 = generatoraccess.getType(blockposition1);
  
                  if (this.a(generatoraccess, blockposition, iblockdata, enumdirection, blockposition1, iblockdata1, generatoraccess.getFluid(blockposition1), fluid1.c())) {
@@ -44,3 +47,30 @@
                      this.a(generatoraccess, blockposition1, iblockdata1, enumdirection, fluid1);
                  }
              }
+@@ -448,12 +474,23 @@
+ 
+             if (fluid1.e()) {
+                 fluid = fluid1;
+-                world.setTypeAndData(blockposition, Blocks.AIR.getBlockData(), 3);
++                // CraftBukkit start
++                FluidLevelChangeEvent event = CraftEventFactory.callFluidLevelChangeEvent(world, blockposition, Blocks.AIR.getBlockData());
++                if (event.isCancelled()) {
++                    return;
++                }
++                world.setTypeAndData(blockposition, ((CraftBlockData) event.getNewData()).getState(), 3);
++                // CraftBukkit end
+             } else if (!fluid1.equals(fluid)) {
+                 fluid = fluid1;
+                 IBlockData iblockdata = fluid1.i();
+-
+-                world.setTypeAndData(blockposition, iblockdata, 2);
++                // CraftBukkit start
++                FluidLevelChangeEvent event = CraftEventFactory.callFluidLevelChangeEvent(world, blockposition, iblockdata);
++                if (event.isCancelled()) {
++                    return;
++                }
++                world.setTypeAndData(blockposition, ((CraftBlockData) event.getNewData()).getState(), 2);
++                // CraftBukkit end
+                 world.getFluidTickList().a(blockposition, fluid1.c(), i);
+                 world.applyPhysics(blockposition, iblockdata.getBlock());
+             }

src/main/java/org/bukkit/craftbukkit/block/CraftBlock.java

@@ -232,7 +232,7 @@ public class CraftBlock implements Block {
 
     @Override
     public String toString() {
-        return "CraftBlock{pos=" + position + ",type=" + getType() + ",data=" + getNMS() + '}';
+        return "CraftBlock{pos=" + position + ",type=" + getType() + ",data=" + getNMS() + ",fluid=" + world.getFluid(position) + '}';
     }
 
     public static BlockFace notchToBlockFace(EnumDirection notch) {

src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java

@@ -835,6 +835,12 @@ public class CraftEventFactory {
         return !event.isCancelled();
     }
 
+    public static FluidLevelChangeEvent callFluidLevelChangeEvent(World world, BlockPosition block, IBlockData newData) {
+        FluidLevelChangeEvent event = new FluidLevelChangeEvent(CraftBlock.at(world, block), CraftBlockData.fromData(newData));
+        world.getServer().getPluginManager().callEvent(event);
+        return event;
+    }
+
     public static FoodLevelChangeEvent callFoodLevelChangeEvent(EntityHuman entity, int level) {
         FoodLevelChangeEvent event = new FoodLevelChangeEvent(entity.getBukkitEntity(), level);
         entity.getBukkitEntity().getServer().getPluginManager().callEvent(event);