using UnityEngine;
#if UNITY_WEBGL && !UNITY_EDITOR
using System.Runtime.InteropServices;
#endif

public class FullscreenController : MonoBehaviour
{
    // Assign this to your Button OnClick
    public void GoFullscreenPortrait()
    {
#if UNITY_WEBGL && !UNITY_EDITOR
        try { WebGL_RequestFullscreenAndPortrait(); } catch { }
#else
        ForcePortraitNative();
#endif
    }

#if UNITY_WEBGL && !UNITY_EDITOR
    // NOTE: name matches the JS function below (fixed the typo)
    [DllImport("__Internal")]
    private static extern void WebGL_RequestFullscreenAndPortrait();
#endif

#if !UNITY_WEBGL || UNITY_EDITOR
    private void ForcePortraitNative()
    {
        // Allow only portrait
        Screen.autorotateToPortrait = true;
        Screen.autorotateToPortraitUpsideDown = false;
        Screen.autorotateToLandscapeLeft = false;
        Screen.autorotateToLandscapeRight = false;
        Screen.orientation = ScreenOrientation.Portrait; // or ScreenOrientation.AutoRotation with only portrait enabled

        // Fullscreen
        Screen.fullScreenMode = FullScreenMode.FullScreenWindow;
        Screen.fullScreen = true;

#if UNITY_ANDROID
        EnableAndroidImmersive(); // hide status/nav bars
#endif
    }
#endif

#if UNITY_ANDROID
    // Immersive sticky for Android
    private void EnableAndroidImmersive()
    {
        using var unityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer");
        using var activity    = unityPlayer.GetStatic<AndroidJavaObject>("currentActivity");
        using var window      = activity.Call<AndroidJavaObject>("getWindow");
        using var decorView   = window.Call<AndroidJavaObject>("getDecorView");

        const int SYSTEM_UI_FLAG_LAYOUT_STABLE          = 0x00000100;
        const int SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION = 0x00000200;
        const int SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN      = 0x00000400;
        const int SYSTEM_UI_FLAG_HIDE_NAVIGATION        = 0x00000002;
        const int SYSTEM_UI_FLAG_FULLSCREEN             = 0x00000004;
        const int SYSTEM_UI_FLAG_IMMERSIVE_STICKY       = 0x00001000;

        int flags = SYSTEM_UI_FLAG_LAYOUT_STABLE
                  | SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                  | SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                  | SYSTEM_UI_FLAG_HIDE_NAVIGATION
                  | SYSTEM_UI_FLAG_FULLSCREEN
                  | SYSTEM_UI_FLAG_IMMERSIVE_STICKY;

        decorView.Call("setSystemUiVisibility", flags);
    }
#endif
}