Merge pull request #77 from rafern/master

Add LocateFeature command

src/main/java/me/rigamortis/seppuku/impl/command/LocateFeatureCommand.java

@@ -0,0 +1,139 @@
+package me.rigamortis.seppuku.impl.command;
+
+import me.rigamortis.seppuku.Seppuku;
+import me.rigamortis.seppuku.api.command.Command;
+import me.rigamortis.seppuku.api.util.StringUtil;
+import me.rigamortis.seppuku.impl.management.WorldManager;
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.multiplayer.ServerData;
+import net.minecraft.client.multiplayer.WorldClient;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.World;
+import net.minecraft.world.WorldSettings;
+import net.minecraft.world.chunk.IChunkProvider;
+import net.minecraft.world.gen.IChunkGenerator;
+import net.minecraft.world.gen.MapGenBase;
+import net.minecraft.world.gen.structure.MapGenStructure;
+import net.minecraft.world.storage.SaveHandlerMP;
+import net.minecraft.world.storage.WorldInfo;
+import net.minecraftforge.common.DimensionManager;
+
+import java.lang.reflect.Field;
+
+public final class LocateFeatureCommand extends Command {
+
+    public LocateFeatureCommand() {
+        super("LocateFeature", new String[]{"LocFeature", "LocateFeat", "LF"}, "Like /locate, but client-side and with an option to override the origin for calculating the nearest feature", "LocateFeature <Feature name>\nLocate <Feature name> <X> <Z>");
+    }
+
+    @Override
+    public void exec(String input) {
+        if (!this.clamp(input, 2, 4)) {
+            this.printUsage();
+            return;
+        }
+
+        final String[] split = input.split(" ");
+
+        if (split.length == 3) {
+            this.printUsage();
+            return;
+        }
+
+        final BlockPos originPos;
+        final String originHint;
+        if (split.length == 4) {
+            if (StringUtil.isInt(split[2])) {
+                if (StringUtil.isInt(split[3])) {
+                    originPos = new BlockPos(Integer.parseInt(split[2]), 64, Integer.parseInt(split[3]));
+                } else {
+                    Seppuku.INSTANCE.errorChat("Unknown number " + "\247f\"" + split[3] + "\"");
+                    return;
+                }
+            } else {
+                Seppuku.INSTANCE.errorChat("Unknown number " + "\247f\"" + split[2] + "\"");
+                return;
+            }
+            originHint = "to " + String.valueOf(originPos.getX()) + ", " + String.valueOf(originPos.getZ());
+        } else {
+            originPos = new BlockPos(Minecraft.getMinecraft().player.posX, 64, Minecraft.getMinecraft().player.posZ);
+            originHint = "you";
+        }
+
+        final ServerData serverData = Minecraft.getMinecraft().getCurrentServerData();
+        if (serverData != null) {
+            final WorldManager.WorldData worldData = Seppuku.INSTANCE.getWorldManager().find(serverData.serverIP);
+            if (worldData != null) {
+                final FakeWorld world = new FakeWorld(worldData.getSeed());
+                final BlockPos pos = world.getNearestStructurePos(split[1], originPos);
+                if (pos == null) {
+                    Seppuku.INSTANCE.errorChat("No structure found " + "\247f\"" + split[1] + "\"");
+                } else {
+                    Seppuku.INSTANCE.logChat(split[1] + " nearest " + originHint + " is at " + String.valueOf(pos.getX()) + ", " + String.valueOf(pos.getZ()));
+                }
+            } else {
+                Seppuku.INSTANCE.errorChat("Seed not set. Use the seed command first");
+            }
+        } else {
+            Seppuku.INSTANCE.errorChat("Cannot locate feature on localhost, since localhost has no seed");
+        }
+    }
+
+    private class FakeWorld extends World {
+        final IChunkGenerator chunkGenerator;
+
+        public FakeWorld(long seed) {
+            this(Minecraft.getMinecraft().world, seed);
+        }
+
+        public FakeWorld(WorldClient worldClient, long seed) {
+            super(new SaveHandlerMP(), new WorldInfo(new WorldSettings(seed, worldClient.getWorldInfo().getGameType(), true, worldClient.getWorldInfo().isHardcoreModeEnabled(), worldClient.getWorldInfo().getTerrainType()), "MpServer"), DimensionManager.createProviderFor(worldClient.provider.getDimension()), null, true);
+            this.provider.setWorld(this);
+            this.chunkGenerator = this.provider.createChunkGenerator();
+
+            // I would use getDeclaredField("world") here, but it fails outside the dev environment
+            // I also tried using ObfuscationReflectionHelper but it wouldn't compile, so I gave up
+            Field worldField = null;
+            for(Field field : MapGenBase.class.getDeclaredFields()) {
+                if (World.class.isAssignableFrom(field.getType())) {
+                    worldField = field;
+                    break;
+                }
+            }
+
+            if (worldField == null) {
+                Seppuku.INSTANCE.errorChat("Could not find \"world\" field; feature location will fail");
+                return;
+            }
+
+            worldField.setAccessible(true);
+
+            for(Field field : this.chunkGenerator.getClass().getDeclaredFields()) {
+                try {
+                    if (MapGenStructure.class.isAssignableFrom(field.getType())) {
+                        field.setAccessible(true);
+                        MapGenBase structureGenerator = (MapGenBase) field.get(this.chunkGenerator);
+                        worldField.set(structureGenerator, this);
+                    }
+                } catch(IllegalAccessException e) {
+                    Seppuku.INSTANCE.errorChat("Potential feature type skipped due to exception");
+                    e.printStackTrace();
+                }
+            }
+        }
+
+        protected IChunkProvider createChunkProvider()
+        {
+            return null;
+        }
+
+        protected boolean isChunkLoaded(int x, int z, boolean allowEmpty)
+        {
+            return false;
+        }
+
+        public BlockPos getNearestStructurePos(String structureName, BlockPos position) {
+            return this.chunkGenerator.getNearestStructurePos(this, structureName, position, false);
+        }
+    }
+}

src/main/java/me/rigamortis/seppuku/impl/management/CommandManager.java

@@ -72,6 +72,7 @@ public final class CommandManager {
         this.commandList.add(new LastInvCommand());
         this.commandList.add(new SearchCommand());
         this.commandList.add(new PlayCommand());
+        this.commandList.add(new LocateFeatureCommand());
 
         //create commands for every value within every module
         loadValueCommands();