From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Warrior <50800980+Warriorrrr@users.noreply.github.com>
Date: Thu, 31 Aug 2023 10:23:06 +0200
Subject: [PATCH] Paper PR: Fix some beacon event issues

Original license: GPLv3
Original project: https://github.com/PaperMC/Paper
Paper pull request: https://github.com/PaperMC/Paper/pull/9674

Closes Paper#8947

Moves the deactivate event call into the onRemove method for the beacon block itself to prevent it from running when the block entity is unloaded. Also fixes an issue where the events were not being called when the beacon beam gets blocked.

The field I added feels a bit wrong but it works, it's to prevent the activation event being called immediately after loading, can't see any better way to differentiate between a newly placed beacon and a newly loaded one.

diff --git a/net/minecraft/world/level/block/entity/BeaconBlockEntity.java b/net/minecraft/world/level/block/entity/BeaconBlockEntity.java
index c2e15c6e1c6bfc5a9d89afc9b8aa9551bad2cc8f..bf79ba5da09b4b3a7152aa5f5175e86b79ec124b 100644
--- a/net/minecraft/world/level/block/entity/BeaconBlockEntity.java
+++ b/net/minecraft/world/level/block/entity/BeaconBlockEntity.java
@@ -173,6 +173,8 @@ public class BeaconBlockEntity extends BlockEntity implements MenuProvider, Name
         return VALID_EFFECTS.contains(effect) ? effect : null;
     }
 
+    public boolean justLoadedAndPreviouslyActive; // Paper PR - consider beacon previously active for first tick to skip activate event/sound
+
     public BeaconBlockEntity(BlockPos pos, BlockState blockState) {
         super(BlockEntityType.BEACON, pos, blockState);
     }
@@ -238,10 +240,15 @@ public class BeaconBlockEntity extends BlockEntity implements MenuProvider, Name
             }
         }
         // Paper start - beacon activation/deactivation events
-        if (originalLevels <= 0 && blockEntity.levels > 0) {
+        // Paper PR start - Fix some beacon event issues
+        final boolean prevActive = originalLevels > 0 && (!blockEntity.beamSections.isEmpty() || (blockEntity.justLoadedAndPreviouslyActive && !blockEntity.checkingBeamSections.isEmpty()));
+        blockEntity.justLoadedAndPreviouslyActive = false;
+        final boolean newActive = blockEntity.levels > 0 && !blockEntity.checkingBeamSections.isEmpty();
+        if (!prevActive && newActive) {
+            // Paper PR end - Fix some beacon event issues
             org.bukkit.block.Block block = org.bukkit.craftbukkit.block.CraftBlock.at(level, pos);
             new io.papermc.paper.event.block.BeaconActivatedEvent(block).callEvent();
-        } else if (originalLevels > 0 && blockEntity.levels <= 0) {
+        } else if (prevActive && !newActive) { // Paper PR - Fix some beacon event issues
             org.bukkit.block.Block block = org.bukkit.craftbukkit.block.CraftBlock.at(level, pos);
             new io.papermc.paper.event.block.BeaconDeactivatedEvent(block).callEvent();
         }
@@ -249,10 +256,10 @@ public class BeaconBlockEntity extends BlockEntity implements MenuProvider, Name
 
         if (blockEntity.lastCheckY >= height) {
             blockEntity.lastCheckY = level.getMinY() - 1;
-            boolean flag = i > 0;
+            boolean flag = prevActive; // Paper PR - Fix MC-183981
             blockEntity.beamSections = blockEntity.checkingBeamSections;
             if (!level.isClientSide) {
-                boolean flag1 = blockEntity.levels > 0;
+                boolean flag1 = newActive; // Paper PR - Fix MC-183981
                 if (!flag && flag1) {
                     playSound(level, pos, SoundEvents.BEACON_ACTIVATE);
 
@@ -296,10 +303,6 @@ public class BeaconBlockEntity extends BlockEntity implements MenuProvider, Name
 
     @Override
     public void setRemoved() {
-        // Paper start - beacon activation/deactivation events
-        org.bukkit.block.Block block = org.bukkit.craftbukkit.block.CraftBlock.at(level, worldPosition);
-        new io.papermc.paper.event.block.BeaconDeactivatedEvent(block).callEvent();
-        // Paper end - beacon activation/deactivation events
         // Paper start - fix MC-153086
         if (this.levels > 0 && !this.beamSections.isEmpty()) {
         playSound(this.level, this.worldPosition, SoundEvents.BEACON_DEACTIVATE);
@@ -427,6 +430,7 @@ public class BeaconBlockEntity extends BlockEntity implements MenuProvider, Name
         this.primaryPower = loadEffect(input, "primary_effect");
         this.secondaryPower = loadEffect(input, "secondary_effect");
         this.levels = input.getIntOr("Levels", 0); // CraftBukkit - SPIGOT-5053, use where available
+        this.justLoadedAndPreviouslyActive = this.levels > 0; // Paper PR - Fix some beacon event issues
         this.name = parseCustomNameSafe(input, "CustomName");
         this.lockKey = LockCode.fromTag(input);
         this.effectRange = input.getDoubleOr(PAPER_RANGE_TAG, -1); // Paper - Custom beacon ranges
@@ -498,4 +502,15 @@ public class BeaconBlockEntity extends BlockEntity implements MenuProvider, Name
         super.setLevel(level);
         this.lastCheckY = level.getMinY() - 1;
     }
+
+    // Paper PR start - Fix some beacon event issues - BeaconDeactivatedEvent
+    @Override
+    public void preRemoveSideEffects(BlockPos pos, BlockState state) {
+        BeaconBlockEntity beacon = this;
+        if (true /*beacon.levels > 0 && !beacon.getBeamSections().isEmpty()*/) { // Calling deactive everytime on remove to keep consistent with Paper's behavior
+            org.bukkit.block.Block block = org.bukkit.craftbukkit.block.CraftBlock.at(this.level, pos);
+            new io.papermc.paper.event.block.BeaconDeactivatedEvent(block).callEvent();
+        }
+    }
+    // Paper PR end - Fix some beacon event issues - BeaconDeactivatedEvent
 }