Implement chunk inversion system.

foundation-chaos/src/main/kotlin/gay/pizza/foundation/chaos/modules/WorldSwapper.kt

@@ -1,7 +1,11 @@
 package gay.pizza.foundation.chaos.modules
 
 import gay.pizza.foundation.chaos.randomPlayer
+import org.bukkit.Chunk
 import org.bukkit.ChunkSnapshot
+import org.bukkit.Material
+import org.bukkit.block.Block
+import org.bukkit.block.data.BlockData
 import org.bukkit.plugin.Plugin
 
 class WorldSwapper(val plugin: Plugin) : ChaosModule {
@@ -9,38 +13,91 @@ class WorldSwapper(val plugin: Plugin) : ChaosModule {
   override fun name(): String = "World Swapper"
   override fun what(): String = "Swaps the world vertically on activation, and un-swaps it on deactivation."
 
-  var snapshot: ChunkSnapshot? = null
+  var chunkInversions = mutableListOf<ChunkInversion>()
 
   override fun activate() {
     val player = plugin.server.randomPlayer() ?: return
-    val chunk = player.world.getChunkAt(player.location)
-    val localSnapshot = chunk.chunkSnapshot
+    val baseChunk = player.chunk
+    recordInvert(baseChunk)
+    player.teleport(player.location.toHighestLocation())
+    val chunksToInvert = player.world.loadedChunks.filter { it != baseChunk }.toMutableList()
 
-    for (x in 0..15) {
-      for (z in 0..15) {
-        val heightRange = (chunk.world.minHeight + 1) until chunk.world.maxHeight
-        for (y in heightRange) {
-          val targetBlock = chunk.getBlock(x, y, z)
-          val inverseY = heightRange.random()
-          val nextBlock = localSnapshot.getBlockData(x, inverseY, z)
-          targetBlock.setBlockData(nextBlock, true)
-        }
+    println("Inverting ${chunksToInvert.size} chunks...")
+    fun scheduleOne() {
+      if (chunksToInvert.isEmpty()) {
+        return
       }
+
+      val chunk = chunksToInvert.removeAt(0)
+      plugin.server.scheduler.runTaskLater(plugin, { ->
+        recordInvert(chunk)
+        scheduleOne()
+      }, 5)
     }
-    snapshot = localSnapshot
+
+    scheduleOne()
+  }
+
+  fun recordInvert(chunk: Chunk) {
+    chunkInversions.add(invertChunk(chunk))
   }
 
   override fun deactivate() {
-    val localSnapshot = snapshot ?: return
-    val world = plugin.server.getWorld(localSnapshot.worldName) ?: return
-    val chunk = world.getChunkAt(localSnapshot.x, localSnapshot.z)
+    fun scheduleOne() {
+      if (chunkInversions.isEmpty()) {
+        return
+      }
 
+      val inversion = chunkInversions.removeAt(0)
+      plugin.server.scheduler.runTaskLater(plugin, { ->
+        inversion.revert()
+        scheduleOne()
+      }, 5)
+    }
+
+    scheduleOne()
+  }
+
+  fun invertChunk(chunk: Chunk): ChunkInversion {
+    val snapshot = chunk.chunkSnapshot
     for (x in 0..15) {
       for (z in 0..15) {
-        val heightRange = chunk.world.minHeight + 1 until chunk.world.maxHeight
-        for (y in heightRange) {
-          val originalBlock = localSnapshot.getBlockData(x, y, z)
-          chunk.getBlock(x, y, z).blockData = originalBlock
+        var sy = chunk.world.minHeight
+        var ey = chunk.world.maxHeight
+        while (sy != ey) {
+          sy++
+          ey--
+          val targetBlock = chunk.getBlock(x, sy, z)
+          val targetBlockData = targetBlock.blockData.clone()
+          val nextBlock = chunk.getBlock(x, ey, z)
+          val nextBlockData = nextBlock.blockData.clone()
+          invertSetBlockData(targetBlock, nextBlockData)
+          invertSetBlockData(nextBlock, targetBlockData)
+        }
+      }
+    }
+    return ChunkInversion(plugin, snapshot)
+  }
+
+  private fun invertSetBlockData(block: Block, data: BlockData) {
+    block.setBlockData(data, false)
+  }
+
+  class ChunkInversion(
+    val plugin: Plugin,
+    val snapshot: ChunkSnapshot
+  ) {
+    fun revert() {
+      val world = plugin.server.getWorld(snapshot.worldName) ?: return
+      val chunk = world.getChunkAt(snapshot.x, snapshot.z)
+
+      for (x in 0..15) {
+        for (z in 0..15) {
+          val heightRange = chunk.world.minHeight + 1 until chunk.world.maxHeight
+          for (y in heightRange) {
+            val originalBlock = snapshot.getBlockData(x, y, z)
+            chunk.getBlock(x, y, z).blockData = originalBlock
+          }
         }
       }
     }