import com.mojang.blaze3d.platform.DisplayData;
import com.mojang.blaze3d.systems.RenderSystem;
import com.mojang.authlib.properties.PropertyMap;
import net.minecraft.SharedConstants;
import net.minecraft.client.Minecraft;
import net.minecraft.client.User;
import net.minecraft.client.main.GameConfig;
import net.minecraft.server.Bootstrap;

import java.io.File;
import java.net.Proxy;
import java.util.OptionalInt;

/**
 * mcfold scaffold —— 只起 MC 的**渲染栈**，不进游戏主循环。
 *
 * 依据（反编译 net.minecraft.client.main.Main 的实测序列）：
 *   Bootstrap.bootStrap()
 *   RenderSystem.initRenderThread(); beginInitialization();
 *   new Minecraft(gameConfig)         ← 构造即完成 GL/资源/渲染器初始化
 *   RenderSystem.finishInitialization()
 * 之后 Main 才起 Game thread 跑主循环 —— 我们**不**走那步。
 */
public class Scaffold {

    public static void main(String[] args) throws Exception {
        String gameDir  = arg(args, "--gameDir", "/home/newqqagent/mcview/instances/default");
        String assets   = arg(args, "--assets",  "/home/newqqagent/mcview/store/vanilla-1.20.1/assets");
        // ★ 索引名必须是 assets/indexes/<name>.json 中真实存在的那个。
        //   version.json 的 assetIndex.id 是 "5"，但 MCLC 落盘用 version.number（1.20.1）
        //   —— 传 "5" 会导致索引加载失败，所有资源/icons 全部找不到（实测踩过）。
        String assetIdx = arg(args, "--assetIndex", "1.20.1");
        int width  = Integer.parseInt(arg(args, "--width",  "1280"));
        int height = Integer.parseInt(arg(args, "--height", "720"));

        System.out.println("[scaffold] bootstrap...");
        // ★ 官方 Main 的实测序列：tryDetectVersion 必须在 bootStrap 之前，
        //   否则 DataFixers.<clinit> 抛 "Game version not set"
        SharedConstants.tryDetectVersion();
        SharedConstants.enableDataFixerOptimizations();
        Bootstrap.bootStrap();
        System.out.println("[scaffold] bootstrap ok, mcVersion=" + SharedConstants.getCurrentVersion().getName());

        File runDir   = new File(gameDir);
        File assetsDir = new File(assets);

        User user = new User("mcfold_cam", "0".repeat(32), "mcfold_cam",
                java.util.Optional.empty(), java.util.Optional.empty(), User.Type.LEGACY);
        PropertyMap props = new PropertyMap();

        GameConfig cfg = new GameConfig(
            new GameConfig.UserData(user, props, props, Proxy.NO_PROXY),
            new DisplayData(width, height, OptionalInt.empty(), OptionalInt.empty(), false),
            new GameConfig.FolderData(
                // ★ 顺序是 (gameDirectory, resourcePackDirectory, assetDirectory, assetIndex)
                //   反着写会把 assets 当游戏目录，导致资源全找不到（实测踩过：icons/icon_16x16.png 404）
                runDir, new File(runDir, "resourcepacks"), assetsDir, assetIdx),
            new GameConfig.GameData(
                false,            // demo
                "mcfold",         // version
                "release",        // versionType
                false,            // disableMultiplayer
                false),           // disableChat
            new GameConfig.QuickPlayData(null, null, null, null)
        );

        System.out.println("[scaffold] RenderSystem init...");
        RenderSystem.initRenderThread();
        RenderSystem.beginInitialization();

        System.out.println("[scaffold] new Minecraft(cfg) ...");
        Minecraft mc = new Minecraft(cfg);

        RenderSystem.finishInitialization();
        System.out.println("[scaffold] OK Minecraft constructed");

        // 检查渲染栈关键对象是否就绪（不启主循环）
        System.out.println("[scaffold] window=" + mc.getWindow().getWidth() + "x" + mc.getWindow().getHeight());
        System.out.println("[scaffold] levelRenderer=" + (mc.levelRenderer != null ? "present" : "null"));
        System.out.println("[scaffold] gameRenderer=" + (mc.gameRenderer != null ? "present" : "null"));
        System.out.println("[scaffold] level=" + (mc.level != null ? "present" : "null (не connected)"));

        System.out.println("[scaffold] DONE (no main loop)");
    }

    private static String arg(String[] a, String key, String def) {
        for (int i = 0; i < a.length - 1; i++)
            if (a[i].equals(key)) return a[i + 1];
        return def;
    }
}