Use methods for palette rewriting, fix "value already present"

common/src/main/java/us/myles/ViaVersion/api/minecraft/chunks/ChunkSection.java

@@ -78,6 +78,24 @@ public class ChunkSection {
         return blocks[idx];
     }
 
+    public int getPaletteSize() {
+        return palette.size();
+    }
+
+    public int getPaletteEntry(int index) {
+        if (index < 0 || index >= palette.size()) throw new IndexOutOfBoundsException();
+        return palette.inverse().get(index);
+    }
+
+    public void setPaletteEntry(int index, int id) {
+        if (index < 0 || index >= palette.size()) throw new IndexOutOfBoundsException();
+        palette.forcePut(id, index);
+    }
+
+    public void replacePaletteEntry(int oldId, int newId) {
+        if (palette.containsKey(oldId)) palette.put(newId, palette.remove(oldId));
+    }
+
     /**
      * Set a block state in the chunk
      * This method will not update non-air blocks count

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_13_1to1_13/packets/WorldPackets.java

@@ -1,6 +1,5 @@
 package us.myles.ViaVersion.protocols.protocol1_13_1to1_13.packets;
 
-import com.google.common.collect.BiMap;
 import us.myles.ViaVersion.api.PacketWrapper;
 import us.myles.ViaVersion.api.minecraft.BlockChangeRecord;
 import us.myles.ViaVersion.api.minecraft.chunks.Chunk;
@@ -29,9 +28,8 @@ public class WorldPackets {
 
                         for (ChunkSection section : chunk.getSections()) {
                             if (section == null) continue;
-                            BiMap<Integer, Integer> inverse = section.getPalette().inverse();
+                            for (int i = 0; i < section.getPaletteSize(); i++) {
-                            for (int i = 0; i < inverse.size(); i++) {
+                                section.setPaletteEntry(i, Protocol1_13_1To1_13.getNewBlockStateId(section.getPaletteEntry(i)));
-                                inverse.put(i, Protocol1_13_1To1_13.getNewBlockStateId(inverse.get(i)));
                             }
                         }
                     }

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_13to1_12_2/packets/WorldPackets.java

@@ -242,14 +242,13 @@ public class WorldPackets {
 
                             boolean willStoreAnyBlock = false;
 
-                            BiMap<Integer, Integer> inverse = section.getPalette().inverse();
+                            for (int p = 0; p < section.getPaletteSize(); p++) {
-                            for (int p = 0; p < inverse.size(); p++) {
+                                int old = section.getPaletteEntry(p);
-                                int old = inverse.get(p);
                                 int newId = toNewId(old);
                                 if (storage.isWelcome(newId)) {
                                     willStoreAnyBlock = true;
                                 }
-                                inverse.put(p, newId);
+                                section.setPaletteEntry(p, newId);
                             }
 
                             if (willStoreAnyBlock) {

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_9_3to1_9_1_2/types/Chunk1_9_1_2Type.java

@@ -54,8 +54,8 @@ public class Chunk1_9_1_2Type extends PartialType<Chunk, ClientWorld> {
             if (world.getEnvironment() == Environment.NORMAL) {
                 section.readSkyLight(input);
             }
-            if (replacePistons && section.getPalette().containsKey(36)) {
+            if (replacePistons) {
-                section.getPalette().put(replacementId, section.getPalette().remove(36));
+                section.replacePaletteEntry(36, replacementId);
             }
         }
 

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_9to1_8/types/Chunk1_9to1_8Type.java

@@ -89,8 +89,8 @@ public class Chunk1_9to1_8Type extends PartialType<Chunk, ClientChunks> {
             ChunkSection section = Types1_8.CHUNK_SECTION.read(input);
             sections[i] = section;
 
-            if (replacePistons && section.getPalette().containsKey(36)) {
+            if (replacePistons) {
-                section.getPalette().put(replacementId, section.getPalette().remove(36));
+                section.replacePaletteEntry(36, replacementId);
             }
         }