From cc7df5a4fc0c3f1c2e7845a46784c2894bf71f39 Mon Sep 17 00:00:00 2001
From: Nassim Jahnke <nassim@njahnke.dev>
Date: Thu, 28 Sep 2023 09:36:30 +1000
Subject: [PATCH] Fix serverbound beacon secondary effect

---
 .../rewriter/BlockItemPacketRewriter1_20_2.java            | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/common/src/main/java/com/viaversion/viabackwards/protocol/protocol1_20to1_20_2/rewriter/BlockItemPacketRewriter1_20_2.java b/common/src/main/java/com/viaversion/viabackwards/protocol/protocol1_20to1_20_2/rewriter/BlockItemPacketRewriter1_20_2.java
index 366a08c8..c72bc9b4 100644
--- a/common/src/main/java/com/viaversion/viabackwards/protocol/protocol1_20to1_20_2/rewriter/BlockItemPacketRewriter1_20_2.java
+++ b/common/src/main/java/com/viaversion/viabackwards/protocol/protocol1_20to1_20_2/rewriter/BlockItemPacketRewriter1_20_2.java
@@ -112,8 +112,11 @@ public final class BlockItemPacketRewriter1_20_2 extends ItemRewriter<Clientboun
         });
 
         protocol.registerServerbound(ServerboundPackets1_19_4.SET_BEACON_EFFECT, wrapper -> {
-            if (wrapper.passthrough(Type.BOOLEAN)) {
-                // Effects start at 1 before 1.20.2
+            // Effects start at 1 before 1.20.2
+            if (wrapper.passthrough(Type.BOOLEAN)) { // Primary effect
+                wrapper.write(Type.VAR_INT, wrapper.read(Type.VAR_INT) - 1);
+            }
+            if (wrapper.passthrough(Type.BOOLEAN)) { // Secondary effect
                 wrapper.write(Type.VAR_INT, wrapper.read(Type.VAR_INT) - 1);
             }
         });