package com.TheRPGAdventurer.server.world;

import java.util.Map.Entry;
import java.util.Random;

import com.TheRPGAdventurer.RealmOfTheDragons;
import com.TheRPGAdventurer.RealmOfTheDragonsConfig;
import com.TheRPGAdventurer.RealmOfTheDragonsLootTables;
import com.TheRPGAdventurer.server.util.Utils;

import net.minecraft.block.Block;
import net.minecraft.init.Biomes;
import net.minecraft.init.Blocks;
import net.minecraft.tileentity.TileEntity;
import net.minecraft.tileentity.TileEntityChest;
import net.minecraft.util.ResourceLocation;
import net.minecraft.util.math.BlockPos;
import net.minecraft.world.World;
import net.minecraft.world.WorldServer;
import net.minecraft.world.chunk.IChunkGenerator;
import net.minecraft.world.chunk.IChunkProvider;
import net.minecraft.world.gen.structure.template.PlacementSettings;
import net.minecraft.world.gen.structure.template.Template;
import net.minecraft.world.gen.structure.template.TemplateManager;
import net.minecraftforge.fml.common.IWorldGenerator;

public class ROTDWorldGenerator implements IWorldGenerator {

	@Override
	public void generate(Random rand, int chunkX, int chunkZ, World world, IChunkGenerator chunkGenerator, IChunkProvider chunkProvider) {
		int blockX = chunkX * 16;
		int blockZ = chunkZ * 16;

		switch (world.provider.getDimension()) {
			case -1:
				generateNether(world, rand, blockX, blockZ);
				break;
			case 0:
				generateOverworld(world, rand, blockX, blockZ);
				break;
			case 1:
				generateEnd(world, rand, blockX, blockZ);
				break;
		}
	}

	private void generateNether(World world, Random rand, int chunkX, int chunkZ) {}
	private void generateEnd(World world, Random rand, int chunkX, int chunkZ) {}

	private void generateOverworld(World world, Random rand, int blockX, int blockZ)  {
		generateOverworldStructures(world, rand, blockX, blockZ);
	}

	private void generateOverworldStructures(World world, Random rand, int blockX, int blockZ) {

		if (RealmOfTheDragonsConfig.spawnStructures) {

			WorldServer server = (WorldServer) world;
			TemplateManager manager = server.getStructureTemplateManager();

			// templates
			Template testhouse = manager.getTemplate(world.getMinecraftServer(), new ResourceLocation(RealmOfTheDragons.MODID, "testhouse"));

			// structures
			if ((int) (Math.random() * RealmOfTheDragonsConfig.testhousechance) == 0) { // testhouse chance is 1500

				int randX = blockX + (int) Math.random() * 16;
				int randZ = blockZ + (int) Math.random() * 16;
				int groundY = getGroundFromAbove(world, randX, randZ);
				BlockPos pos = new BlockPos(randX, groundY, randZ);

				if (canSpawnHere(testhouse, world, pos) && world.getBiome(pos) == Biomes.PLAINS) {

					RealmOfTheDragons.LOGGER.info("Generating testhouse at " + pos);
					testhouse.addBlocksToWorld(world, pos, new PlacementSettings());
				}
			}
		}
    }
			/**
			 * Gets the Y-value of the ground at a specifix x/y coordinate.
			 * @param world
			 * @param x
			 * @param z
			 * @return
			 */
			private int getGroundFromAbove(World world, int x, int z) {
				int y = 255;
				boolean foundGround = false;
				while(!foundGround && y-- >= 63)
				{
					Block blockAt = world.getBlockState(new BlockPos(x,y,z)).getBlock();
					foundGround = blockAt == Blocks.DIRT || blockAt == Blocks.GRASS || blockAt == Blocks.SAND || blockAt == Blocks.SNOW || blockAt == Blocks.SNOW_LAYER;
				}

				return y;
			}

			private boolean canSpawnHere(Template template, World world, BlockPos posAboveGround) {
				int zwidth = template.getSize().getZ();
				int xwidth = template.getSize().getX();

				// check all the corners to see which ones are replaceable
				boolean corner1 = isCornerValid(world, posAboveGround);
				boolean corner2 = isCornerValid(world, posAboveGround.add(xwidth, 0, zwidth));

				// if Y > 20 and all corners pass the test, it's okay to spawn the structure
				return posAboveGround.getY() > 63 && corner1 && corner2;
			}

			private boolean isCornerValid(World world, BlockPos pos) {
				int variation = 3;
				int highestBlock = getGroundFromAbove(world, pos.getX(), pos.getZ());

				if (highestBlock > pos.getY() - variation && highestBlock < pos.getY() + variation)
					return true;

				RealmOfTheDragons.LOGGER.info("Canceling gen for this structure.");

				return true;
			}

		}