// Zielpfad: src/main/java/ovh/glitchlabs/ornamentum/client/ClientSkyboxTracker.java
package ovh.glitchlabs.ornamentum.client;

import net.minecraft.client.Minecraft;
import net.minecraft.client.player.LocalPlayer;
import net.minecraft.client.multiplayer.ClientLevel;
import net.minecraft.core.BlockPos;
import ovh.glitchlabs.ornamentum.blocks.entity.SkyboxBlockEntity;

import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;

public class ClientSkyboxTracker {

    private static final Set<BlockPos> POSITIONS = ConcurrentHashMap.newKeySet();
    private static final int FADE_DISTANCE = 12;

    public static void register(BlockPos pos) {
        POSITIONS.add(pos);
    }

    public static void unregister(BlockPos pos) {
        POSITIONS.remove(pos);
    }

    /**
     * Bündelt alle für das Rendering relevanten Werte des aktuell "gewinnenden"
     * (nächstgelegenen, aktivsten) Skybox-Blocks.
     */
    public record ActiveSkybox(float blend, int colorIndex, boolean starsEnabled, int texturePreset) {
    }

    /**
     * @return null, wenn kein Skybox-Block in Reichweite ist, sonst die Werte
     * des Blocks mit dem stärksten Überblend-Faktor.
     */
    public static ActiveSkybox getActive() {
        LocalPlayer player = Minecraft.getInstance().player;
        ClientLevel level = Minecraft.getInstance().level;
        if (player == null || level == null || POSITIONS.isEmpty()) {
            return null;
        }

        ActiveSkybox best = null;
        float bestBlend = 0f;

        for (BlockPos pos : POSITIONS) {
            if (!(level.getBlockEntity(pos) instanceof SkyboxBlockEntity be)) {
                continue;
            }

            double dist = Math.sqrt(player.blockPosition().distSqr(pos));
            int range = be.getRange();
            if (dist >= range) {
                continue;
            }

            float blend = dist <= range - FADE_DISTANCE
                    ? 1f
                    : (float) ((range - dist) / FADE_DISTANCE);

            if (blend > bestBlend) {
                bestBlend = blend;
                best = new ActiveSkybox(blend, be.getColorIndex(), be.isStarsEnabled(), be.getTexturePreset());
            }
        }

        return best;
    }
}