package com.mojang.blaze3d.opengl;

import java.util.Set;
import net.fabricmc.api.EnvType;
import net.fabricmc.api.Environment;
import org.lwjgl.opengl.ARBDirectStateAccess;
import org.lwjgl.opengl.GLCapabilities;

@Environment(EnvType.CLIENT)
public abstract class DirectStateAccess {
	public static DirectStateAccess create(GLCapabilities capabilities, Set<String> enabledExtensions) {
		if (capabilities.GL_ARB_direct_state_access && GlDevice.USE_GL_ARB_direct_state_access) {
			enabledExtensions.add("GL_ARB_direct_state_access");
			return new DirectStateAccess.Core();
		} else {
			return new DirectStateAccess.Emulated();
		}
	}

	abstract int createFrameBufferObject();

	abstract void bindFrameBufferTextures(int frameBuffer, int colorTexture, int depthTexture, int level, int target);

	abstract void blitFrameBuffers(
		int readFrameBuffer, int drawFrameBuffer, int srcX0, int srcY0, int srcX1, int srcY1, int destX0, int destY0, int destX1, int destY1, int mask, int filter
	);

	@Environment(EnvType.CLIENT)
	static class Core extends DirectStateAccess {
		@Override
		public int createFrameBufferObject() {
			return ARBDirectStateAccess.glCreateFramebuffers();
		}

		@Override
		public void bindFrameBufferTextures(int frameBuffer, int colorTexture, int depthTexture, int level, int target) {
			ARBDirectStateAccess.glNamedFramebufferTexture(frameBuffer, 36064, colorTexture, level);
			ARBDirectStateAccess.glNamedFramebufferTexture(frameBuffer, 36096, depthTexture, level);
			if (target != 0) {
				GlStateManager._glBindFramebuffer(target, frameBuffer);
			}
		}

		@Override
		public void blitFrameBuffers(
			int readFrameBuffer, int drawFrameBuffer, int srcX0, int srcY0, int srcX1, int srcY1, int destX0, int destY0, int destX1, int destY1, int mask, int filter
		) {
			ARBDirectStateAccess.glBlitNamedFramebuffer(readFrameBuffer, drawFrameBuffer, srcX0, srcY0, srcX1, srcY1, destX0, destY0, destX1, destY1, mask, filter);
		}
	}

	@Environment(EnvType.CLIENT)
	static class Emulated extends DirectStateAccess {
		@Override
		public int createFrameBufferObject() {
			return GlStateManager.glGenFramebuffers();
		}

		@Override
		public void bindFrameBufferTextures(int frameBuffer, int colorTexture, int depthTexture, int level, int target) {
			int i = target == 0 ? '販' : target;
			int j = GlStateManager.getFrameBuffer(i);
			GlStateManager._glBindFramebuffer(i, frameBuffer);
			GlStateManager._glFramebufferTexture2D(i, 36064, 3553, colorTexture, level);
			GlStateManager._glFramebufferTexture2D(i, 36096, 3553, depthTexture, level);
			if (target == 0) {
				GlStateManager._glBindFramebuffer(i, j);
			}
		}

		@Override
		public void blitFrameBuffers(
			int readFrameBuffer, int drawFrameBuffer, int srcX0, int srcY0, int srcX1, int srcY1, int destX0, int destY0, int destX1, int destY1, int mask, int filter
		) {
			int i = GlStateManager.getFrameBuffer(36008);
			int j = GlStateManager.getFrameBuffer(36009);
			GlStateManager._glBindFramebuffer(36008, readFrameBuffer);
			GlStateManager._glBindFramebuffer(36009, drawFrameBuffer);
			GlStateManager._glBlitFrameBuffer(srcX0, srcY0, srcX1, srcY1, destX0, destY0, destX1, destY1, mask, filter);
			GlStateManager._glBindFramebuffer(36008, i);
			GlStateManager._glBindFramebuffer(36009, j);
		}
	}
}