package net.minecraft.client.renderer;

import com.mojang.blaze3d.PrimitiveTopology;
import com.mojang.blaze3d.buffers.GpuBuffer;
import com.mojang.blaze3d.buffers.GpuBufferSlice;
import com.mojang.blaze3d.pipeline.RenderPipeline;
import com.mojang.blaze3d.pipeline.RenderTarget;
import com.mojang.blaze3d.systems.RenderPass;
import com.mojang.blaze3d.systems.RenderSystem;
import com.mojang.blaze3d.textures.GpuTextureView;
import com.mojang.blaze3d.vertex.BufferBuilder;
import com.mojang.blaze3d.vertex.ByteBufferBuilder;
import com.mojang.blaze3d.vertex.DefaultVertexFormat;
import com.mojang.blaze3d.vertex.MeshData;
import java.util.Optional;
import java.util.OptionalDouble;
import net.fabricmc.api.EnvType;
import net.fabricmc.api.Environment;
import net.minecraft.client.Minecraft;
import net.minecraft.client.renderer.state.level.CameraRenderState;
import org.joml.Matrix4f;
import org.joml.Matrix4fStack;

@Environment(EnvType.CLIENT)
public class DebugCrosshairRenderer implements AutoCloseable {
	private static final float CROSSHAIR_SCALE = 0.01F;
	private static final int CROSSHAIR_INDEX_COUNT = 36;
	private final GpuBuffer crosshairBuffer;
	private final RenderSystem.AutoStorageIndexBuffer crosshairIndicies = RenderSystem.getSequentialBuffer(PrimitiveTopology.LINES);

	public DebugCrosshairRenderer() {
		try (ByteBufferBuilder byteBufferBuilder = ByteBufferBuilder.exactlySized(DefaultVertexFormat.POSITION_COLOR_NORMAL_LINE_WIDTH.getVertexSize() * 12 * 2)) {
			BufferBuilder bufferBuilder = new BufferBuilder(byteBufferBuilder, PrimitiveTopology.LINES, DefaultVertexFormat.POSITION_COLOR_NORMAL_LINE_WIDTH);
			bufferBuilder.addVertex(0.0F, 0.0F, 0.0F).setColor(-16777216).setNormal(1.0F, 0.0F, 0.0F).setLineWidth(4.0F);
			bufferBuilder.addVertex(1.0F, 0.0F, 0.0F).setColor(-16777216).setNormal(1.0F, 0.0F, 0.0F).setLineWidth(4.0F);
			bufferBuilder.addVertex(0.0F, 0.0F, 0.0F).setColor(-16777216).setNormal(0.0F, 1.0F, 0.0F).setLineWidth(4.0F);
			bufferBuilder.addVertex(0.0F, 1.0F, 0.0F).setColor(-16777216).setNormal(0.0F, 1.0F, 0.0F).setLineWidth(4.0F);
			bufferBuilder.addVertex(0.0F, 0.0F, 0.0F).setColor(-16777216).setNormal(0.0F, 0.0F, 1.0F).setLineWidth(4.0F);
			bufferBuilder.addVertex(0.0F, 0.0F, 1.0F).setColor(-16777216).setNormal(0.0F, 0.0F, 1.0F).setLineWidth(4.0F);
			bufferBuilder.addVertex(0.0F, 0.0F, 0.0F).setColor(-65536).setNormal(1.0F, 0.0F, 0.0F).setLineWidth(2.0F);
			bufferBuilder.addVertex(1.0F, 0.0F, 0.0F).setColor(-65536).setNormal(1.0F, 0.0F, 0.0F).setLineWidth(2.0F);
			bufferBuilder.addVertex(0.0F, 0.0F, 0.0F).setColor(-16711936).setNormal(0.0F, 1.0F, 0.0F).setLineWidth(2.0F);
			bufferBuilder.addVertex(0.0F, 1.0F, 0.0F).setColor(-16711936).setNormal(0.0F, 1.0F, 0.0F).setLineWidth(2.0F);
			bufferBuilder.addVertex(0.0F, 0.0F, 0.0F).setColor(-8421377).setNormal(0.0F, 0.0F, 1.0F).setLineWidth(2.0F);
			bufferBuilder.addVertex(0.0F, 0.0F, 1.0F).setColor(-8421377).setNormal(0.0F, 0.0F, 1.0F).setLineWidth(2.0F);

			try (MeshData meshData = bufferBuilder.buildOrThrow()) {
				this.crosshairBuffer = RenderSystem.getDevice().createBuffer(() -> "Crosshair vertex buffer", 32, meshData.vertexBuffer());
			}
		}
	}

	public void close() {
		this.crosshairBuffer.close();
	}

	public void render(final CameraRenderState cameraState, final int guiScale) {
		Matrix4fStack modelViewStack = RenderSystem.getModelViewStack();
		modelViewStack.pushMatrix();
		modelViewStack.translate(0.0F, 0.0F, -1.0F);
		modelViewStack.rotateX(cameraState.xRot * (float) (Math.PI / 180.0));
		modelViewStack.rotateY(cameraState.yRot * (float) (Math.PI / 180.0));
		float crosshairScale = 0.01F * guiScale;
		modelViewStack.scale(-crosshairScale, crosshairScale, -crosshairScale);
		RenderPipeline renderPipelineOutline = RenderPipelines.LINES;
		RenderPipeline renderPipelineFill = RenderPipelines.LINES_DEPTH_BIAS;
		RenderTarget mainRenderTarget = Minecraft.getInstance().gameRenderer.mainRenderTarget();
		GpuTextureView colorTexture = mainRenderTarget.getColorTextureView();
		GpuTextureView depthTexture = mainRenderTarget.getDepthTextureView();
		GpuBuffer indexBuffer = this.crosshairIndicies.getBuffer(36);
		GpuBufferSlice dynamicTransform = RenderSystem.getDynamicUniforms().writeTransform(new Matrix4f(modelViewStack));

		try (RenderPass renderPass = RenderSystem.getDevice()
				.createCommandEncoder()
				.createRenderPass(() -> "3d crosshair", colorTexture, Optional.empty(), depthTexture, OptionalDouble.empty())) {
			renderPass.setPipeline(renderPipelineOutline);
			RenderSystem.bindDefaultUniforms(renderPass);
			renderPass.setVertexBuffer(0, this.crosshairBuffer.slice());
			renderPass.setIndexBuffer(indexBuffer, this.crosshairIndicies.type());
			renderPass.setUniform("DynamicTransforms", dynamicTransform);
			renderPass.drawIndexed(0, 0, 18, 1);
			renderPass.setPipeline(renderPipelineFill);
			renderPass.drawIndexed(0, 18, 18, 1);
		}

		modelViewStack.popMatrix();
	}
}