package com.mojang.blaze3d.pipeline;

import com.mojang.blaze3d.GpuFormat;
import com.mojang.blaze3d.systems.GpuDevice;
import com.mojang.blaze3d.systems.RenderPass;
import com.mojang.blaze3d.systems.RenderSystem;
import com.mojang.blaze3d.textures.FilterMode;
import com.mojang.blaze3d.textures.GpuTexture;
import com.mojang.blaze3d.textures.GpuTextureView;
import java.util.Optional;
import java.util.OptionalDouble;
import net.minecraft.client.renderer.RenderPipelines;
import org.jspecify.annotations.Nullable;

public abstract class RenderTarget {
	private static int UNNAMED_RENDER_TARGETS = 0;
	public int width;
	public int height;
	protected final String label;
	public final boolean useDepth;
	protected final GpuFormat format;
	@Nullable
	protected GpuTexture colorTexture;
	@Nullable
	protected GpuTextureView colorTextureView;
	@Nullable
	protected GpuTexture depthTexture;
	@Nullable
	protected GpuTextureView depthTextureView;

	public RenderTarget(@Nullable final String label, final boolean useDepth, final GpuFormat format) {
		this.label = label == null ? "FBO " + UNNAMED_RENDER_TARGETS++ : label;
		this.useDepth = useDepth;
		this.format = format;
	}

	public void resize(final int width, final int height) {
		RenderSystem.assertOnRenderThread();
		this.destroyBuffers();
		this.createBuffers(width, height);
	}

	public void destroyBuffers() {
		RenderSystem.assertOnRenderThread();
		if (this.depthTexture != null) {
			this.depthTexture.close();
			this.depthTexture = null;
		}

		if (this.depthTextureView != null) {
			this.depthTextureView.close();
			this.depthTextureView = null;
		}

		if (this.colorTexture != null) {
			this.colorTexture.close();
			this.colorTexture = null;
		}

		if (this.colorTextureView != null) {
			this.colorTextureView.close();
			this.colorTextureView = null;
		}
	}

	public void copyDepthFrom(final RenderTarget source) {
		RenderSystem.assertOnRenderThread();
		if (this.depthTexture == null) {
			throw new IllegalStateException("Trying to copy depth texture to a RenderTarget without a depth texture");
		} else if (source.depthTexture == null) {
			throw new IllegalStateException("Trying to copy depth texture from a RenderTarget without a depth texture");
		} else {
			RenderSystem.getDevice().createCommandEncoder().copyTextureToTexture(source.depthTexture, this.depthTexture, 0, 0, 0, 0, 0, this.width, this.height);
		}
	}

	public void createBuffers(final int width, final int height) {
		RenderSystem.assertOnRenderThread();
		GpuDevice device = RenderSystem.getDevice();
		int maxTextureSize = device.getDeviceInfo().limits().maxTextureSize();
		if (width > 0 && width <= maxTextureSize && height > 0 && height <= maxTextureSize) {
			this.width = width;
			this.height = height;
			if (this.useDepth) {
				this.depthTexture = device.createTexture(() -> this.label + " / Depth", 15, GpuFormat.D32_FLOAT, width, height, 1, 1);
				this.depthTextureView = device.createTextureView(this.depthTexture);
			}

			this.colorTexture = device.createTexture(() -> this.label + " / Color", 15, this.format, width, height, 1, 1);
			this.colorTextureView = device.createTextureView(this.colorTexture);
		} else {
			throw new IllegalArgumentException("Window " + width + "x" + height + " size out of bounds (max. size: " + maxTextureSize + ")");
		}
	}

	public void blitAndBlendToTexture(final GpuTextureView output, final GpuTextureView outputDepth) {
		RenderSystem.assertOnRenderThread();

		try (RenderPass renderPass = RenderSystem.getDevice()
				.createCommandEncoder()
				.createRenderPass(() -> "Blit render target", output, Optional.empty(), outputDepth, OptionalDouble.empty())) {
			renderPass.setPipeline(RenderPipelines.ENTITY_OUTLINE_BLIT);
			RenderSystem.bindDefaultUniforms(renderPass);
			renderPass.bindTexture("InSampler", this.colorTextureView, RenderSystem.getSamplerCache().getClampToEdge(FilterMode.NEAREST));
			renderPass.draw(3, 1, 0, 0);
		}
	}

	@Nullable
	public GpuTexture getColorTexture() {
		return this.colorTexture;
	}

	@Nullable
	public GpuTextureView getColorTextureView() {
		return this.colorTextureView;
	}

	@Nullable
	public GpuTexture getDepthTexture() {
		return this.depthTexture;
	}

	@Nullable
	public GpuTextureView getDepthTextureView() {
		return this.depthTextureView;
	}
}