no guarantees this patch works but who knows

patches/server/0139-Add-StructureGenerateEvent.patch

@@ -0,0 +1,39 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Nahuel <nahueldolores@hotmail.com>
+Date: Sat, 9 Jan 2021 15:36:59 +0100
+Subject: [PATCH] Add StructureGenerateEvent
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Co-authored-by: Mariell Hoversholm <proximyst@proximyst.com>
+
+diff --git a/src/main/java/net/minecraft/world/level/chunk/ChunkGenerator.java b/src/main/java/net/minecraft/world/level/chunk/ChunkGenerator.java
+index e4591c0b3c8547cc6f4e2a0891fc378ee4334d9e..11b0697f668f6c0965a74081c149585fdf49b209 100644
+--- a/src/main/java/net/minecraft/world/level/chunk/ChunkGenerator.java
++++ b/src/main/java/net/minecraft/world/level/chunk/ChunkGenerator.java
+@@ -458,6 +458,14 @@ public abstract class ChunkGenerator implements BiomeManager.NoiseBiomeSource {
+             if (structurestart == null || !structurestart.isValid()) {
+                 StructureStart<?> structurestart1 = StructureFeatures.STRONGHOLD.generate(registryManager, this, this.biomeSource, structureManager, worldSeed, chunkcoordintpair, ChunkGenerator.fetchReferences(structureAccessor, chunk, sectionposition, StructureFeature.STRONGHOLD), structuresettingsfeature, chunk, ChunkGenerator::validStrongholdBiome);
+ 
++                // Purpur start
++                if (new org.purpurmc.purpur.event.world.StructureGenerateEvent(
++                        structureAccessor.getWorld().getWorld(),
++                        org.bukkit.StructureType.getStructureTypes().get(structurestart1.getFeature().getFeatureName().toLowerCase()),
++                        chunkcoordintpair.x,
++                        chunkcoordintpair.z
++                ).callEvent())
++                // Purpur end
+                 structureAccessor.setStartForFeature(sectionposition, StructureFeature.STRONGHOLD, structurestart1, chunk);
+             }
+         }