Purpur/purpur-server/minecraft-patches/features/0021-lightning-transforms-blocks.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: granny <granny@purpurmc.org>
Date: Sun, 27 Aug 2023 02:09:51 -0700
Subject: [PATCH] lightning transforms blocks


diff --git a/net/minecraft/world/entity/LightningBolt.java b/net/minecraft/world/entity/LightningBolt.java
index e81eabf901e755e1254fff98cdd1e609cf07aab8..d971384c64baf6954f92ac9d2c1c9f782b11a6e3 100644
--- a/net/minecraft/world/entity/LightningBolt.java
+++ b/net/minecraft/world/entity/LightningBolt.java
@@ -38,6 +38,10 @@ public class LightningBolt extends Entity {
     public boolean visualOnly;
     private @Nullable ServerPlayer cause;
     private final Set<Entity> hitEntities = Sets.newHashSet();
+    // Purpur start - lightning transforms blocks
+    public List<org.bukkit.craftbukkit.block.CraftBlockState> blocks;
+    private BlockPos blockPos;
+    // Purpur end - lightning transforms blocks
     private int blocksSetOnFire;
     public boolean isEffect; // Paper - Properly handle lightning effects api
 
@@ -46,6 +50,10 @@ public class LightningBolt extends Entity {
         this.life = 2;
         this.seed = this.random.nextLong();
         this.flashes = this.random.nextInt(3) + 1;
+        // Purpur start - lightning transforms blocks
+        this.blocks = this.getTransformedBlocks();
+        this.blockPos = this.getStrikePosition();
+        // Purpur end - lightning transforms blocks
     }
 
     public void setVisualOnly(boolean visualOnly) {
@@ -73,6 +81,65 @@ public class LightningBolt extends Entity {
         }
     }
 
+    // Purpur start - lightning transforms blocks
+    private List<org.bukkit.craftbukkit.block.CraftBlockState> getTransformedBlocks() {
+        if (!level().purpurConfig.lightningTransformsBlocks) return new java.util.ArrayList<>();
+
+        BlockPos blockposition = this.getStrikePosition();
+        BlockState iblockdata = this.level().getBlockState(blockposition);
+        BlockPos pos;
+        BlockState iblockdata2;
+
+        if (iblockdata.is(net.minecraft.world.level.block.Blocks.LIGHTNING_ROD)) {
+            pos = blockposition.below();
+            iblockdata2 = this.level().getBlockState(pos);
+        } else {
+            iblockdata2 = iblockdata;
+            pos = blockposition;
+        }
+
+        if (level().purpurConfig.lightningTurnsSandIntoGlass && iblockdata2.is(net.minecraft.world.level.block.Blocks.SAND)) {
+            level().setBlock(pos, net.minecraft.world.level.block.Blocks.GLASS.defaultBlockState(), 2);
+        } else if (level().purpurConfig.lightningTurnsStoneIntoObsidian && iblockdata2.is(net.minecraft.world.level.block.Blocks.STONE)) {
+            level().setBlock(pos, net.minecraft.world.level.block.Blocks.OBSIDIAN.defaultBlockState(), 2);
+        } else if (level().purpurConfig.lightningTurnsWaterIntoStone && iblockdata2.is(net.minecraft.world.level.block.Blocks.WATER)) {
+            level().setBlock(pos, net.minecraft.world.level.block.Blocks.STONE.defaultBlockState(), 2);
+        } else if (!level().purpurConfig.lightningTurnsNearbySandIntoGlass) {
+            return new java.util.ArrayList<>();
+        }
+
+        org.bukkit.craftbukkit.util.BlockStateListPopulator blockList = new org.bukkit.craftbukkit.util.BlockStateListPopulator(level());
+        BlockPos.breadthFirstTraversal(
+                pos,
+                level().purpurConfig.lightningTurnsNearbySandIntoGlassMaxDepth,
+                level().purpurConfig.lightningTurnsNearbySandIntoGlassMaxIterations,
+                (validPos, queueAdder) -> {
+                    for (net.minecraft.core.Direction direction : net.minecraft.core.Direction.values()) {
+                        queueAdder.accept(validPos.relative(direction));
+                    }
+                },
+        blockPos -> {
+                    if (blockPos.equals(pos)) {
+                        return BlockPos.TraversalNodeStatus.ACCEPT;
+                    } else {
+                        BlockState iblockdata3 = blockList.getBlockState(blockPos);
+
+                        if (!iblockdata3.is(net.minecraft.world.level.block.Blocks.SAND)) { // Purpur
+                            return BlockPos.TraversalNodeStatus.SKIP;
+                        } else {
+                            blockList.setBlock(blockPos, net.minecraft.world.level.block.Blocks.GLASS.defaultBlockState(), 3);
+                            return BlockPos.TraversalNodeStatus.ACCEPT;
+                        }
+                    }
+                }
+            );
+
+        this.blockPos = pos; // TODO find a way to not need this variable
+
+        return blockList.getSnapshotBlocks();
+    }
+    // Purpur end - lightning transforms blocks
+
     @Override
     public void tick() {
         super.tick();
@@ -107,6 +174,7 @@ public class LightningBolt extends Entity {
                 }
 
                 this.powerLightningRod();
+                if (level().purpurConfig.lightningTransformsBlocks) net.minecraft.world.level.block.SpongeBlock.processBlocksBreadthFirstSearch(level(), this.blockPos, this.blocks, false); // Purpur - lightning transforms blocks
                 clearCopperOnLightningStrike(this.level(), this.getStrikePosition(), this); // Paper - Call EntityChangeBlockEvent
                 this.gameEvent(GameEvent.LIGHTNING_STRIKE);
             }
diff --git a/net/minecraft/world/level/block/SpongeBlock.java b/net/minecraft/world/level/block/SpongeBlock.java
index 83185c5341fe0033f542520bc1436a31eed27bf5..73d9f24586e960359be9fd8d941c3d2c7584de43 100644
--- a/net/minecraft/world/level/block/SpongeBlock.java
+++ b/net/minecraft/world/level/block/SpongeBlock.java
@@ -102,13 +102,20 @@ public class SpongeBlock extends Block {
             );
         // CraftBukkit start
         java.util.List<org.bukkit.craftbukkit.block.CraftBlockState> snapshots = blockList.getSnapshotBlocks(); // Is a clone
+    // Purpur start - lightning transforms blocks
+        return processBlocksBreadthFirstSearch(level, pos, snapshots, true);
+    }
+    public static boolean processBlocksBreadthFirstSearch(net.minecraft.world.level.Level level, net.minecraft.core.BlockPos pos, java.util.List<org.bukkit.craftbukkit.block.CraftBlockState> snapshots, boolean emitSpongeAbscorbEvent) {
+    // Purpur end - lightning transforms blocks
         if (!snapshots.isEmpty()) {
             final org.bukkit.block.Block sponge = org.bukkit.craftbukkit.block.CraftBlock.at(level, pos);
 
+            if (emitSpongeAbscorbEvent) { // Purpur - lightning transforms blocks
             org.bukkit.event.block.SpongeAbsorbEvent event = new org.bukkit.event.block.SpongeAbsorbEvent(sponge, (java.util.List<org.bukkit.block.BlockState>) (java.util.List) snapshots);
             if (!event.callEvent()) {
                 return false;
             }
+            } // Purpur - lightning transforms blocks
 
             for (org.bukkit.craftbukkit.block.CraftBlockState snapshot : snapshots) {
                 BlockPos blockPos = snapshot.getPosition();