package net.minecraft.client.gui.screens.inventory;

import java.util.List;
import net.fabricmc.api.EnvType;
import net.fabricmc.api.Environment;
import net.minecraft.client.gui.GuiGraphics;
import net.minecraft.client.renderer.RenderType;
import net.minecraft.resources.ResourceLocation;
import net.minecraft.util.ARGB;
import net.minecraft.world.inventory.AbstractContainerMenu;
import net.minecraft.world.inventory.Slot;

@Environment(EnvType.CLIENT)
public class CyclingSlotBackground {
	private static final int ICON_CHANGE_TICK_RATE = 30;
	private static final int ICON_SIZE = 16;
	private static final int ICON_TRANSITION_TICK_DURATION = 4;
	private final int slotIndex;
	private List<ResourceLocation> icons = List.of();
	private int tick;
	private int iconIndex;

	public CyclingSlotBackground(int slotIndex) {
		this.slotIndex = slotIndex;
	}

	public void tick(List<ResourceLocation> icons) {
		if (!this.icons.equals(icons)) {
			this.icons = icons;
			this.iconIndex = 0;
		}

		if (!this.icons.isEmpty() && ++this.tick % 30 == 0) {
			this.iconIndex = (this.iconIndex + 1) % this.icons.size();
		}
	}

	public void render(AbstractContainerMenu containerMenu, GuiGraphics guiGraphics, float partialTick, int x, int y) {
		Slot slot = containerMenu.getSlot(this.slotIndex);
		if (!this.icons.isEmpty() && !slot.hasItem()) {
			boolean bl = this.icons.size() > 1 && this.tick >= 30;
			float f = bl ? this.getIconTransitionTransparency(partialTick) : 1.0F;
			if (f < 1.0F) {
				int i = Math.floorMod(this.iconIndex - 1, this.icons.size());
				this.renderIcon(slot, (ResourceLocation)this.icons.get(i), 1.0F - f, guiGraphics, x, y);
			}

			this.renderIcon(slot, (ResourceLocation)this.icons.get(this.iconIndex), f, guiGraphics, x, y);
		}
	}

	private void renderIcon(Slot slot, ResourceLocation icon, float alpha, GuiGraphics guiGraphics, int x, int y) {
		guiGraphics.blitSprite(RenderType::guiTextured, icon, x + slot.x, y + slot.y, 16, 16, ARGB.white(alpha));
	}

	private float getIconTransitionTransparency(float partialTick) {
		float f = this.tick % 30 + partialTick;
		return Math.min(f, 4.0F) / 4.0F;
	}
}