First creation of an NMS Handler. Not sure if relocation works yet.

Signed-off-by: Gabriel Harris-Rouquette <gabizou@me.com>

bukkit/1_8_8/src/main/java/com/gmail/nossr50/bukkit/v1_8/NmsHandler.java

@@ -0,0 +1,93 @@
+package com.gmail.nossr50.bukkit.v1_8;
+
+import com.gmail.nossr50.VersionedHandler;
+import com.gmail.nossr50.mcMMO;
+import com.google.common.base.Joiner;
+import com.google.common.collect.ImmutableMap;
+import net.minecraft.server.v1_8_R3.Blocks;
+import net.minecraft.server.v1_8_R3.EntityTypes;
+import net.minecraft.server.v1_8_R3.IBlockData;
+import net.minecraft.server.v1_8_R3.IBlockState;
+import net.minecraft.server.v1_8_R3.MinecraftKey;
+import net.minecraft.server.v1_8_R3.RegistryBlocks;
+import org.bukkit.block.Block;
+import org.bukkit.block.BlockState;
+import org.bukkit.craftbukkit.v1_8_R3.entity.CraftEntity;
+import org.bukkit.craftbukkit.v1_8_R3.util.CraftMagicNumbers;
+import org.bukkit.entity.Entity;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+@SuppressWarnings({"unused", "Duplicates"}) // We use reflection to load this handler on 1.8 versions
+public class NmsHandler extends VersionedHandler {
+
+    /**
+     * Static reference to the block registry. Don't really care about the fact that
+     * it is being stored as a reference here, but for imports reasons, it's smaller
+     * line length makes it optimal to read for method usages.
+     */
+    private static final RegistryBlocks<MinecraftKey, net.minecraft.server.v1_8_R3.Block> BLOCK_REGISTRY = net.minecraft.server.v1_8_R3.Block.REGISTRY;
+    /**
+     * We can keep track of block state id's by generating them on demand, i.e., when
+     * they're being requested from Blocks, or BlockDatas.
+     */
+    private static final RegistryBlocks<MinecraftKey, IBlockData> BLOCK_STATE_REGISTRY = new RegistryBlocks<>(BLOCK_REGISTRY.c(Blocks.AIR)); // Default to AIR
+
+    NmsHandler(mcMMO plugin) {
+        super(plugin);
+    }
+
+    @Override
+    public String getIdFor(Block block) {
+        // We have to get the underlying nms block by the block, which might as well just be the type id.
+        final net.minecraft.server.v1_8_R3.Block block1 = CraftMagicNumbers.getBlock(block);
+        // The registry.c(T) will return MinecraftKey, and the toString() returns the "$mod:$name", so "minecraft:stone"
+        final MinecraftKey key = BLOCK_REGISTRY.c(block1);
+        return key.toString();
+    }
+
+    @Override
+    public String getIdFor(Entity entity) {
+        // EntityTypes maintains the maps of Class<? extends nms.Entity> to String for id's and to numerical id numbers.
+        // We of course are using the method that gets us the String id of the entity, such as "minecraft:creeper"
+        return EntityTypes.b(((CraftEntity) entity).getHandle());
+    }
+
+    @Override
+    public String getIdFor(BlockState block) {
+        // Much like #getIdFor(Block) except here we have the "state" by numerical id. So.. we have to grab it from
+        // the world.
+        final net.minecraft.server.v1_8_R3.Block nmsBlock = net.minecraft.server.v1_8_R3.Block.REGISTRY.a(block.getTypeId());
+        final MinecraftKey blockKey = net.minecraft.server.v1_8_R3.Block.REGISTRY.c(nmsBlock);
+        final IBlockData blockState = nmsBlock.fromLegacyData(block.getRawData());
+        // Now we can check if our blockstate registry actually has the block state.
+        final MinecraftKey stateKey = BLOCK_STATE_REGISTRY.c(blockState);
+        if (stateKey != null) { // If the state has been registered by the handler, then by all means.
+            return stateKey.toString();
+        }
+        // If not, well, it needs to have a key generated and registered.
+        final String nameSpace = blockKey.a();
+        StringBuilder builder = new StringBuilder();
+        builder.append(blockKey.a()); // We only want to get the block id, not the domain id, since that's going to be appended later
+
+        // Get the full Property -> Value mapping for the block state
+        final ImmutableMap<IBlockState, Comparable> properties = blockState.b();
+        if (!properties.isEmpty()) {
+            builder.append('[');
+            Joiner joiner = Joiner.on(',');
+            List<String> propertyValues = new ArrayList<>();
+            for (Map.Entry<IBlockState, Comparable> entry : properties.entrySet()) {
+                // a() gets the inputted "name" for the state, the value, well, that gets the value, which is always toStringable.
+                propertyValues.add(entry.getKey().a() + "=" + entry.getValue());
+            }
+            builder.append(joiner.join(propertyValues));
+            builder.append(']');
+        }
+        // Now we can make the MinecraftKey...
+        final MinecraftKey newKey = new MinecraftKey(builder.toString());
+        BLOCK_STATE_REGISTRY.a(newKey, blockState);
+        return newKey.toString();
+    }
+}