package com.mojang.blaze3d.systems;

import com.google.common.annotations.VisibleForTesting;
import com.mojang.blaze3d.textures.AddressMode;
import com.mojang.blaze3d.textures.FilterMode;
import com.mojang.blaze3d.textures.GpuSampler;
import java.util.OptionalDouble;
import net.fabricmc.api.EnvType;
import net.fabricmc.api.Environment;

@Environment(EnvType.CLIENT)
public class SamplerCache {
	private final GpuSampler[] samplers = new GpuSampler[32];

	public void initialize() {
		GpuDevice device = RenderSystem.getDevice();
		if (AddressMode.values().length == 2 && FilterMode.values().length == 2) {
			for (AddressMode addressModeU : AddressMode.values()) {
				for (AddressMode addressModeV : AddressMode.values()) {
					for (FilterMode minFilter : FilterMode.values()) {
						for (FilterMode magFilter : FilterMode.values()) {
							for (boolean useMipmaps : new boolean[]{true, false}) {
								this.samplers[encode(addressModeU, addressModeV, minFilter, magFilter, useMipmaps)] = device.createSampler(
									addressModeU, addressModeV, minFilter, magFilter, 1, useMipmaps ? OptionalDouble.empty() : OptionalDouble.of(0.0)
								);
							}
						}
					}
				}
			}
		} else {
			throw new IllegalStateException("AddressMode and FilterMode enum sizes must be 2 - if you expanded them, please update SamplerCache");
		}
	}

	public GpuSampler getSampler(
		final AddressMode addressModeU, final AddressMode addressModeV, final FilterMode minFilter, final FilterMode magFilter, final boolean useMipmaps
	) {
		return this.samplers[encode(addressModeU, addressModeV, minFilter, magFilter, useMipmaps)];
	}

	public GpuSampler getClampToEdge(final FilterMode minMag) {
		return this.getSampler(AddressMode.CLAMP_TO_EDGE, AddressMode.CLAMP_TO_EDGE, minMag, minMag, false);
	}

	public GpuSampler getClampToEdge(final FilterMode minMag, final boolean mipmaps) {
		return this.getSampler(AddressMode.CLAMP_TO_EDGE, AddressMode.CLAMP_TO_EDGE, minMag, minMag, mipmaps);
	}

	public GpuSampler getRepeat(final FilterMode minMag) {
		return this.getSampler(AddressMode.REPEAT, AddressMode.REPEAT, minMag, minMag, false);
	}

	public GpuSampler getRepeat(final FilterMode minMag, final boolean mipmaps) {
		return this.getSampler(AddressMode.REPEAT, AddressMode.REPEAT, minMag, minMag, mipmaps);
	}

	public void close() {
		for (GpuSampler sampler : this.samplers) {
			sampler.close();
		}
	}

	@VisibleForTesting
	static int encode(
		final AddressMode addressModeU, final AddressMode addressModeV, final FilterMode minFilter, final FilterMode magFilter, final boolean useMipmaps
	) {
		int result = 0;
		result |= addressModeU.ordinal() & 1;
		result |= (addressModeV.ordinal() & 1) << 1;
		result |= (minFilter.ordinal() & 1) << 2;
		result |= (magFilter.ordinal() & 1) << 3;
		if (useMipmaps) {
			result |= 16;
		}

		return result;
	}
}