package net.minecraft.client.gui.components.debug;

import java.util.ArrayList;
import java.util.List;
import net.fabricmc.api.EnvType;
import net.fabricmc.api.Environment;
import net.minecraft.client.Minecraft;
import net.minecraft.core.BlockPos;
import net.minecraft.resources.Identifier;
import net.minecraft.server.level.ServerChunkCache;
import net.minecraft.server.level.ServerLevel;
import net.minecraft.world.entity.Entity;
import net.minecraft.world.level.Level;
import net.minecraft.world.level.biome.BiomeSource;
import net.minecraft.world.level.biome.Climate;
import net.minecraft.world.level.chunk.ChunkGenerator;
import net.minecraft.world.level.chunk.LevelChunk;
import net.minecraft.world.level.levelgen.RandomState;
import org.jspecify.annotations.Nullable;

@Environment(EnvType.CLIENT)
public class DebugEntryChunkGeneration implements DebugScreenEntry {
	private static final Identifier GROUP = Identifier.withDefaultNamespace("chunk_generation");
	private final List<String> result = new ArrayList();
	@Nullable
	private BlockPos lastPos = null;

	@Override
	public void display(
		final DebugScreenDisplayer displayer,
		@Nullable final Level serverOrClientLevel,
		@Nullable final LevelChunk clientChunk,
		@Nullable final LevelChunk serverChunk
	) {
		Minecraft minecraft = Minecraft.getInstance();
		Entity entity = minecraft.getCameraEntity();
		ServerLevel serverLevel = serverOrClientLevel instanceof ServerLevel level ? level : null;
		if (entity != null && serverLevel != null) {
			BlockPos feetPos = entity.blockPosition();
			if (!feetPos.equals(this.lastPos)) {
				this.update(serverChunk, feetPos, serverLevel);
			}

			displayer.addToGroup(GROUP, this.result);
		}
	}

	private void update(@Nullable final LevelChunk serverChunk, final BlockPos feetPos, final ServerLevel serverLevel) {
		this.result.clear();
		this.lastPos = feetPos;
		ServerChunkCache chunkSource = serverLevel.getChunkSource();
		ChunkGenerator generator = chunkSource.getGenerator();
		RandomState randomState = chunkSource.randomState();
		generator.addDebugScreenInfo(this.result, randomState, feetPos);
		Climate.Sampler sampler = randomState.sampler();
		BiomeSource biomeSource = generator.getBiomeSource();
		biomeSource.addDebugInfo(this.result, feetPos, sampler);
		if (serverChunk != null && serverChunk.isOldNoiseGeneration()) {
			this.result.add("Blending: Old");
		}
	}
}