item-despawn-timer/src/main/java/whirlfrenzy/itemdespawntimer/config/ServerConfig.java

package whirlfrenzy.itemdespawntimer.config;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import net.fabricmc.api.EnvType;
import net.fabricmc.loader.api.FabricLoader;
import net.minecraft.core.registries.BuiltInRegistries;
import net.minecraft.world.entity.item.ItemEntity;
import whirlfrenzy.itemdespawntimer.ItemDespawnTimer;
import java.io.*; import java.nio.file.*; import java.util.*;

public final class ServerConfig {
    private static final Gson GSON = new GsonBuilder().setPrettyPrinting().create();
    private static Data data = new Data();
    public static final class Data {
        public int defaultDespawnSeconds = 300;
        public boolean allowInfiniteLifetime = true;
        public Map<String,Integer> itemDespawnSeconds = new LinkedHashMap<>();
    }
    private ServerConfig() {}
    public static void load() {
        // The common/main initializer also runs in a physical Minecraft client.
        // Never create or read the server config there: a client installation owns
        // presentation settings only. Integrated singleplayer uses server defaults
        // in memory; a dedicated server owns the persistent server config file.
        if (FabricLoader.getInstance().getEnvironmentType() != EnvType.SERVER) {
            data = new Data();
            return;
        }

        Path p = FabricLoader.getInstance().getConfigDir().resolve("item-despawn-timer-server.json");
        try {
            if (Files.exists(p)) { try (Reader r=Files.newBufferedReader(p)) { Data d=GSON.fromJson(r,Data.class); if(d!=null)data=d; } }
            else { Files.createDirectories(p.getParent()); try(Writer w=Files.newBufferedWriter(p)){GSON.toJson(data,w);} }
        } catch(Exception e){ ItemDespawnTimer.LOGGER.error("Cannot load server config",e); }
    }
    public static int lifespanTicks(ItemEntity entity) {
        String id = BuiltInRegistries.ITEM.getKey(entity.getItem().getItem()).toString();
        int seconds = data.itemDespawnSeconds.getOrDefault(id, data.defaultDespawnSeconds);
        if (seconds < 0 && data.allowInfiniteLifetime) return Integer.MAX_VALUE;
        return Math.max(1, seconds) * 20;
    }
}