WorldGenDungeon.java

package cofh.lib.world;

import static cofh.lib.world.WorldGenMinableCluster.*;
import static java.lang.Math.abs;

import cofh.lib.util.WeightedRandomBlock;
import cofh.lib.util.WeightedRandomNBTTag;

import java.util.Arrays;
import java.util.List;
import java.util.Random;

import net.minecraft.init.Blocks;
import net.minecraft.nbt.NBTTagCompound;
import net.minecraft.tileentity.TileEntityChest;
import net.minecraft.tileentity.TileEntityMobSpawner;
import net.minecraft.util.WeightedRandom;
import net.minecraft.util.WeightedRandomChestContent;
import net.minecraft.world.World;
import net.minecraft.world.gen.feature.WorldGenerator;
import net.minecraftforge.common.ChestGenHooks;
import net.minecraftforge.common.DungeonHooks.DungeonMob;

public class WorldGenDungeon extends WorldGenerator
{
	private final List<WeightedRandomBlock> walls;
	private final WeightedRandomBlock[] genBlock;
	private final WeightedRandomNBTTag[] spawners;
	public int minWidthX = 2, maxWidthX = 3;
	public int minWidthZ = 2, maxWidthZ = 3;
	public int minHeight = 3, maxHeight = 3;
	public int minHoles = 1, maxHoles = 5;
	public int maxChests = 2;
	public List<DungeonMob> lootTables = Arrays.asList(new DungeonMob(100, ChestGenHooks.DUNGEON_CHEST));
	public List<WeightedRandomBlock> floor;

	public WorldGenDungeon(List<WeightedRandomBlock> blocks, List<WeightedRandomBlock> material, List<WeightedRandomNBTTag> mobs) {

		walls = blocks;
		floor = walls;
		spawners = mobs.toArray(new WeightedRandomNBTTag[mobs.size()]);
		genBlock = material.toArray(new WeightedRandomBlock[material.size()]);
	}

	@Override
	public boolean generate(World world, Random rand, int xStart, int yStart, int zStart)
	{
		if (yStart <= 2)
			return false;

		int height = nextInt(rand, maxHeight - minHeight + 1) + minHeight;
		int xWidth = nextInt(rand, maxWidthX - minWidthX + 1) + minWidthX;
		int zWidth = nextInt(rand, maxWidthZ - minWidthZ + 1) + minWidthZ;
		int holes = 0;
		int x, y, z;

		int floor = yStart - 1, ceiling = yStart + height + 1;

		for (x = xStart - xWidth - 1; x <= xStart + xWidth + 1; ++x) {
			for (z = zStart - zWidth - 1; z <= zStart + zWidth + 1; ++z) {
				for (y = floor; y <= ceiling; ++y) {

					if (y == floor && !canGenerateInBlock(world, x, y, z, genBlock))
						return false;

					if (y == ceiling && !canGenerateInBlock(world, x, y, z, genBlock))
						return false;

					if ((abs(x - xStart) == xWidth + 1 || abs(z - zStart) == zWidth + 1) && y == yStart &&
							world.isAirBlock(x, y, z) && world.isAirBlock(x, y + 1, z))
						++holes;
				}
			}
		}

		if (holes < minHoles || holes > maxHoles)
			return false;

		NBTTagCompound tag = (NBTTagCompound) ((WeightedRandomNBTTag)WeightedRandom.getRandomItem(rand, spawners)).tag;
		ChestGenHooks table = ChestGenHooks.getInfo(((DungeonMob)WeightedRandom.getRandomItem(rand, lootTables)).type);

		for (x = xStart - xWidth - 1; x <= xStart + xWidth + 1; ++x) {
			for (z = zStart - zWidth - 1; z <= zStart + zWidth + 1; ++z) {
				for (y = yStart + height; y >= floor; --y) {

					if ((abs(x - xStart) != xWidth + 1 || abs(z - zStart) != zWidth + 1) && y != ceiling) {
						world.setBlockToAir(x, y, z);
					}
					else if (y >= 0 && !canGenerateInBlock(world, x, y - 1, z, genBlock)) {
						world.setBlockToAir(x, y, z);
					}
					else if (canGenerateInBlock(world, x, y, z, genBlock)) {
						if (y == floor)
							generateBlock(world, x, y, z, this.floor);
						else
							generateBlock(world, x, y, z, walls);
					}
				}
			}
		}

		for (int i = maxChests; i --> 0; ) {
			for (int j = 0; j < 3; ++j) {
				x = xStart + nextInt(rand, xWidth * 2 + 1) - xWidth;
				z = zStart + nextInt(rand, zWidth * 2 + 1) - zWidth;

				if (world.isAirBlock(x, yStart, z)) {
					int walls = 0;

					if (isWall(world, x - 1, yStart, z))
						++walls;

					if (isWall(world, x + 1, yStart, z))
						++walls;

					if (isWall(world, x, yStart, z - 1))
						++walls;

					if (isWall(world, x, yStart, z + 1))
						++walls;

					if (walls >= 1 && walls <= 2) {
						world.setBlock(x, yStart, z, Blocks.chest, 0, 2);
						TileEntityChest chest = (TileEntityChest)world.getTileEntity(x, yStart, z);

						if (chest != null) {
							WeightedRandomChestContent.generateChestContents(rand, table.getItems(rand), chest, table.getCount(rand));
						}

						break;
					}
				}
			}
		}

		world.setBlock(xStart, yStart, zStart, Blocks.mob_spawner, 0, 2);
		TileEntityMobSpawner spawner = (TileEntityMobSpawner)world.getTileEntity(xStart, yStart, zStart);

		if (spawner != null) {
			spawner.func_145881_a().readFromNBT(tag);
		} else {
			System.err.println("Failed to fetch mob spawner entity at (" + xStart + ", " + yStart + ", " + zStart + ")");
		}

		return true;
	}

	private static int nextInt(Random rand, int v) {
		if (v <= 1)
			return 0;
		return rand.nextInt(v);
	}

	private boolean isWall(World world, int x, int y, int z) {

		int metadata = world.getBlockMetadata(x, y, z);
		return WeightedRandomBlock.isBlockContained(world.getBlock(x, y, z), metadata, walls);
	}

}