Fix #500

nova/src/main/kotlin/xyz/xenondevs/nova/patch/Patcher.kt

@@ -20,6 +20,7 @@ import xyz.xenondevs.nova.patch.impl.FieldFilterPatch
 import xyz.xenondevs.nova.patch.impl.block.BlockBehaviorPatches
 import xyz.xenondevs.nova.patch.impl.block.BlockMigrationPatches
 import xyz.xenondevs.nova.patch.impl.block.DisableBackingStateLogicPatch
+import xyz.xenondevs.nova.patch.impl.block.EarlyBlockPlaceEventPatch
 import xyz.xenondevs.nova.patch.impl.block.FluidFlowPatch
 import xyz.xenondevs.nova.patch.impl.block.TripwireLogicPatch
 import xyz.xenondevs.nova.patch.impl.bossbar.BossBarOriginPatch
@@ -64,7 +65,7 @@ internal object Patcher {
             BroadcastPacketPatch, EventPreventionPatch, WearablePatch, BossBarOriginPatch,
             FakePlayerLastHurtPatch, BlockBehaviorPatches, ChunkSchedulingPatch, DisableBackingStateLogicPatch,
             ItemStackDataComponentsPatch, EnchantmentPatches, TagsPatch, RepairPatches, BlockMigrationPatches,
-            TripwireLogicPatch, FluidFlowPatch
+            TripwireLogicPatch, FluidFlowPatch, EarlyBlockPlaceEventPatch
         ).filter(Transformer::shouldTransform).toSet()
     }
 

nova/src/main/kotlin/xyz/xenondevs/nova/patch/impl/block/EarlyBlockPlaceEventPatch.kt

@@ -0,0 +1,45 @@
+package xyz.xenondevs.nova.patch.impl.block
+
+import net.minecraft.world.item.BlockItem
+import net.minecraft.world.item.context.BlockPlaceContext
+import net.minecraft.world.level.block.state.BlockState
+import org.objectweb.asm.Opcodes
+import org.objectweb.asm.tree.MethodInsnNode
+import xyz.xenondevs.bytebase.jvm.VirtualClassPath
+import xyz.xenondevs.bytebase.util.calls
+import xyz.xenondevs.bytebase.util.replaceEvery
+import xyz.xenondevs.nova.LOGGER
+import xyz.xenondevs.nova.patch.MultiTransformer
+import xyz.xenondevs.nova.util.reflection.ReflectionUtils
+import xyz.xenondevs.nova.util.toNovaPos
+import xyz.xenondevs.nova.world.block.logic.place.BlockPlacing
+import java.util.logging.Level
+
+private val BLOCK_ITEM_PLACE_BLOCK = ReflectionUtils.getMethod(BlockItem::class, "placeBlock", BlockPlaceContext::class, BlockState::class)
+
+internal object EarlyBlockPlaceEventPatch : MultiTransformer(BlockItem::class) {
+
+    override fun transform() {
+        VirtualClassPath[BlockItem::place].replaceEvery(
+            0, 0,
+            { invokeStatic(::placeBlock) }
+        ) { it.opcode == Opcodes.INVOKEVIRTUAL && (it as MethodInsnNode).calls(BLOCK_ITEM_PLACE_BLOCK) }
+        dumpAll()
+    }
+
+    @JvmStatic
+    fun placeBlock(blockItem: BlockItem, context: BlockPlaceContext, state: BlockState): Boolean {
+        try {
+            val pos = context.clickedPos.toNovaPos(context.level.world)
+            if (!BlockPlacing.handleBlockPlace(pos)) {
+                context.player?.containerMenu?.sendAllDataToRemote()
+                return false
+            }
+        } catch(t: Throwable) {
+            LOGGER.log(Level.SEVERE, "An exception occurred while handling early block place event", t)
+        }
+
+        return BLOCK_ITEM_PLACE_BLOCK.invoke(blockItem, context, state) as Boolean
+    }
+
+}

nova/src/main/kotlin/xyz/xenondevs/nova/world/block/logic/place/BlockPlacing.kt

@@ -10,8 +10,6 @@ import org.bukkit.event.EventHandler
 import org.bukkit.event.EventPriority
 import org.bukkit.event.Listener
 import org.bukkit.event.block.Action
-import org.bukkit.event.block.BlockMultiPlaceEvent
-import org.bukkit.event.block.BlockPlaceEvent
 import org.bukkit.event.player.PlayerBucketEmptyEvent
 import org.bukkit.event.player.PlayerBucketFillEvent
 import org.bukkit.event.player.PlayerInteractEvent
@@ -63,18 +61,10 @@ internal object BlockPlacing : Listener {
     // However, we want to permit this for built-in custom blocks, as those might have their
     // WorldDataManager entry set before this event is called (block migration patch)
 
-    @EventHandler(ignoreCancelled = true)
-    private fun handleBlockPlace(event: BlockPlaceEvent) {
-        val blockState = WorldDataManager.getBlockState(event.block.pos)
-        event.isCancelled = blockState != null && blockState.block.id.namespace != "nova"
-    }
-
-    @EventHandler(ignoreCancelled = true)
-    private fun handleBlockPlace(event: BlockMultiPlaceEvent) {
-        event.isCancelled = event.replacedBlockStates.any {
-            val blockState = WorldDataManager.getBlockState(it.location.pos)
-            blockState != null && blockState.block.id.namespace != "nova"
-        }
+    // requires earlier block place event because BlockMigrator has already removed WorldDataManager entry already otherwise
+    fun handleBlockPlace(pos: BlockPos): Boolean {
+        val blockState = WorldDataManager.getBlockState(pos)
+        return blockState == null || blockState.block.id.namespace == "nova"
     }
 
     @EventHandler(ignoreCancelled = true)