Gale/patches/server/0051-Dragon-respawn-end-crystal-proximity-check.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Martijn Muijsers <martijnmuijsers@live.nl>
Date: Mon, 7 Aug 2023 22:02:38 +0200
Subject: [PATCH] Dragon respawn end crystal proximity check

License: GPL-3.0 (https://www.gnu.org/licenses/gpl-3.0.html)
Gale - https://galemc.org

diff --git a/src/main/java/net/minecraft/world/item/EndCrystalItem.java b/src/main/java/net/minecraft/world/item/EndCrystalItem.java
index ca1edc083847b47bb450b291723aca778a5912dc..428eed6ad35b59bdf293ca727fa3e81520a8bf0b 100644
--- a/src/main/java/net/minecraft/world/item/EndCrystalItem.java
+++ b/src/main/java/net/minecraft/world/item/EndCrystalItem.java
@@ -56,7 +56,7 @@ public class EndCrystalItem extends Item {
                         EndDragonFight enderdragonbattle = ((ServerLevel) world).getDragonFight();
 
                         if (enderdragonbattle != null) {
-                            enderdragonbattle.tryRespawn();
+                            enderdragonbattle.tryRespawn(blockposition1); // Gale - check placed end crystal to portal proximity before attempting to respawn dragon
                         }
                     }
 
diff --git a/src/main/java/net/minecraft/world/level/dimension/end/EndDragonFight.java b/src/main/java/net/minecraft/world/level/dimension/end/EndDragonFight.java
index 02d5a5b799bfe90993bc6868369d31f43d5b7fd6..9cb6a36ac210574a3d62202b16058e9fdc94691e 100644
--- a/src/main/java/net/minecraft/world/level/dimension/end/EndDragonFight.java
+++ b/src/main/java/net/minecraft/world/level/dimension/end/EndDragonFight.java
@@ -535,6 +535,12 @@ public class EndDragonFight {
     }
 
     public boolean tryRespawn() { // CraftBukkit - return boolean
+        // Gale start - check placed end crystal to portal proximity before attempting to respawn dragon
+        return this.tryRespawn(null);
+    }
+
+    public boolean tryRespawn(@Nullable BlockPos placedEndCrystalBlockPos) { // CraftBukkit - return boolean
+        // Gale end - check placed end crystal to portal proximity before attempting to respawn dragon
         if (this.dragonKilled && this.respawnStage == null) {
             BlockPos blockposition = this.portalLocation;
 
@@ -552,6 +558,22 @@ public class EndDragonFight {
                 blockposition = this.portalLocation;
             }
 
+            // Gale start - check placed end crystal to portal proximity before attempting to respawn dragon
+            if (placedEndCrystalBlockPos != null) {
+                // The end crystal must be 0 or 1 higher than the portal origin
+                int dy = placedEndCrystalBlockPos.getY() - blockposition.getY();
+                if (dy != 0 && dy != 1) {
+                    return false;
+                }
+                // The end crystal must be within a distance of 1 in one planar direction, and 3 in the other
+                int dx = placedEndCrystalBlockPos.getX() - blockposition.getX();
+                int dz = placedEndCrystalBlockPos.getZ() - blockposition.getZ();
+                if (!((dx >= -1 && dx <= 1 && dz >= -3 && dz <= 3) || (dx >= -3 && dx <= 3 && dz >= -1 && dz <= 1))) {
+                    return false;
+                }
+            }
+            // Gale end - check placed end crystal to portal proximity before attempting to respawn dragon
+
             List<EndCrystal> list = Lists.newArrayList();
             BlockPos blockposition1 = blockposition.above(1);
             Iterator iterator = Direction.Plane.HORIZONTAL.iterator();