EZCheat/src/main/java/com/cimeyclust/ezcheat/Ezcheat.java

package com.cimeyclust.ezcheat;

import com.google.common.reflect.TypeToken;
import com.google.gson.Gson;
import com.mojang.logging.LogUtils;
import net.minecraft.client.Minecraft;
import net.minecraft.core.registries.Registries;
import net.minecraft.network.chat.Component;
import net.minecraft.resources.ResourceLocation;
import net.minecraft.server.MinecraftServer;
import net.minecraft.server.level.ServerPlayer;
import net.minecraft.world.food.FoodProperties;
import net.minecraft.world.item.BlockItem;
import net.minecraft.world.item.CreativeModeTab;
import net.minecraft.world.item.CreativeModeTabs;
import net.minecraft.world.item.Item;
import net.minecraft.world.level.block.Block;
import net.minecraft.world.level.block.Blocks;
import net.minecraft.world.level.block.state.BlockBehaviour;
import net.minecraft.world.level.material.MapColor;
import net.minecraftforge.api.distmarker.Dist;
import net.minecraftforge.common.MinecraftForge;
import net.minecraftforge.event.BuildCreativeModeTabContentsEvent;
import net.minecraftforge.event.server.ServerStartingEvent;
import net.minecraftforge.eventbus.api.IEventBus;
import net.minecraftforge.eventbus.api.SubscribeEvent;
import net.minecraftforge.fml.ModList;
import net.minecraftforge.fml.ModLoadingContext;
import net.minecraftforge.fml.common.Mod;
import net.minecraftforge.fml.config.ModConfig;
import net.minecraftforge.fml.event.lifecycle.FMLClientSetupEvent;
import net.minecraftforge.fml.event.lifecycle.FMLCommonSetupEvent;
import net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext;
import net.minecraftforge.fml.loading.moddiscovery.ModFileInfo;
import net.minecraftforge.forgespi.language.IModInfo;
import net.minecraftforge.network.NetworkRegistry;
import net.minecraftforge.network.simple.SimpleChannel;
import net.minecraftforge.registries.DeferredRegister;
import net.minecraftforge.registries.ForgeRegistries;
import net.minecraftforge.registries.RegistryObject;
import org.apache.commons.codec.digest.DigestUtils;
import org.slf4j.Logger;

import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Type;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;

@Mod(Ezcheat.MODID)
public class Ezcheat {
    public static final String MODID = "ezcheat";

    // Directly reference a slf4j logger
    private static final Logger LOGGER = LogUtils.getLogger();

    public static final String PROTOCOL_VERSION = "1";
    public static final SimpleChannel NETWORK = NetworkRegistry.newSimpleChannel(
            new ResourceLocation(MODID, "main"),
            () -> PROTOCOL_VERSION, PROTOCOL_VERSION::equals, PROTOCOL_VERSION::equals
    );

    public static Map<String, String> getInstalledModHashes() {
        Map<String, String> modHashes = new HashMap<>();

        for (IModInfo mod : ModList.get().getMods()) {
            Optional<Path> modFile = Optional.ofNullable(mod.getOwningFile().getFile().getFilePath());
            modFile.ifPresent(path -> {
                try (InputStream in = Files.newInputStream(path)) {
                    String hash = DigestUtils.sha256Hex(in); // Apache Commons Codec
                    modHashes.put(mod.getModId(), hash);
                } catch (IOException e) {
                    LOGGER.error("Failed to read mod file for {}: {}", mod.getModId(), e.getMessage());
                }
            });
        }

        return modHashes;
    }

    public static void handlePlayerModHashes(ServerPlayer player, Map<String, String> modHashes) {
        // Request an external whitelist
        MinecraftServer server = player.getServer();
        if (server == null) return;

        server.execute(() -> {
            try {
                URL url = new URL(Config.modEndpointUrl);
                HttpURLConnection conn = (HttpURLConnection) url.openConnection();
                conn.setRequestMethod("GET");

                InputStream in = conn.getInputStream();
                String response = new String(in.readAllBytes());
                in.close();

                Gson gson = new Gson();
                Type type = new TypeToken<Map<String, String>>() {}.getType();
                Map<String, String> allowedMods = gson.fromJson(response, type);

                StringBuilder unallowedMods = new StringBuilder("Unallowed mods: ");
                for (Map.Entry<String, String> entry : modHashes.entrySet()) {
                    String modid = entry.getKey();
                    String hash = entry.getValue();

                    if (!allowedMods.containsKey(modid) || !allowedMods.get(modid).equalsIgnoreCase(hash)) {
                        unallowedMods.append(modid).append(", ");
                    }
                }

                if (!unallowedMods.isEmpty()) {
                    unallowedMods.setLength(unallowedMods.length() - 2); // Remove last comma and space
                    player.connection.disconnect(Component.literal(unallowedMods.toString()));
                }
            } catch (IOException e) {
                Ezcheat.LOGGER.error("Modprüfung fehlgeschlagen", e);
            }
        });
    }

    public Ezcheat() {
        ModLoadingContext.get().registerConfig(ModConfig.Type.COMMON, Config.SPEC);

        NETWORK.registerMessage(0, ModHashesPacket.class,
                ModHashesPacket::encode,
                ModHashesPacket::decode,
                ModHashesPacket::handle
        );
    }

    // You can use SubscribeEvent and let the Event Bus discover methods to call
    @SubscribeEvent
    public void onServerStarting(ServerStartingEvent event) {

    }

    // You can use EventBusSubscriber to automatically register all static methods in the class annotated with @SubscribeEvent
    @Mod.EventBusSubscriber(modid = MODID, bus = Mod.EventBusSubscriber.Bus.MOD, value = Dist.CLIENT)
    public static class ClientModEvents {

        @SubscribeEvent
        public static void onClientSetup(FMLClientSetupEvent event) {
            event.enqueueWork(() -> {
                if (Minecraft.getInstance().getConnection() != null) {
                    Map<String, String> modHashes = Ezcheat.getInstalledModHashes();
                    Ezcheat.NETWORK.sendToServer(new ModHashesPacket(modHashes));
                }
            });
        }
    }
}