UnityExplorer/src/UI/UIManager.cs

using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;
using UnityExplorer.Core.Inspectors;
using UnityExplorer.UI.Main;
using System.IO;
using System.Reflection;
using UnityExplorer.UI.Reusable;
using UnityExplorer.Core.Input;
using System;
using UnityExplorer.Core.Config;
using UnityExplorer.UI.Utility;

namespace UnityExplorer.UI
{
    public static class UIManager
    {
        public static GameObject CanvasRoot { get; private set; }
        public static EventSystem EventSys { get; private set; }

        internal static Font ConsoleFont { get; private set; }

        //internal static Sprite ResizeCursor { get; private set; }
        internal static Shader BackupShader { get; private set; }

        public static bool ShowMenu
        {
            get => s_showMenu;
            set => SetShowMenu(value);
        }
        public static bool s_showMenu;

        private static bool s_doneUIInit;
        private static float s_timeSinceStartup;

        internal static void CheckUIInit()
        {
            if (s_doneUIInit)
                return;

            s_timeSinceStartup += Time.deltaTime;

            if (s_timeSinceStartup > 0.1f)
            {
                s_doneUIInit = true;
                try
                {
                    Init();
                    ExplorerCore.Log("Initialized UnityExplorer UI.");

                    if (ExplorerConfig.Instance.Hide_On_Startup)
                        ShowMenu = false;

                    // InspectorManager.Instance.Inspect(Tests.TestClass.Instance);
                }
                catch (Exception e)
                {
                    ExplorerCore.LogWarning($"Exception setting up UI: {e}");
                }
            }
        }

        public static void Init()
        {
            LoadBundle();

            // Create core UI Canvas and Event System handler
            CreateRootCanvas();

            // Create submodules
            new MainMenu();
            InspectUnderMouse.UI.ConstructUI();
            PanelDragger.LoadCursorImage();

            // Force refresh of anchors
            Canvas.ForceUpdateCanvases();
        }

        private static GameObject CreateRootCanvas()
        {
            GameObject rootObj = new GameObject("ExplorerCanvas");
            UnityEngine.Object.DontDestroyOnLoad(rootObj);
            rootObj.layer = 5;

            CanvasRoot = rootObj;
            CanvasRoot.transform.position = new Vector3(0f, 0f, 1f);

            EventSys = rootObj.AddComponent<EventSystem>();
            InputManager.AddUIModule();

            Canvas canvas = rootObj.AddComponent<Canvas>();
            canvas.renderMode = RenderMode.ScreenSpaceCamera;
            canvas.referencePixelsPerUnit = 100;
            canvas.sortingOrder = 999;
            //canvas.pixelPerfect = false;

            CanvasScaler scaler = rootObj.AddComponent<CanvasScaler>();
            scaler.referenceResolution = new Vector2(1920, 1080);
            scaler.screenMatchMode = CanvasScaler.ScreenMatchMode.Expand;

            rootObj.AddComponent<GraphicRaycaster>();

            return rootObj;
        }

        private static void SetShowMenu(bool show)
        {
            if (s_showMenu == show)
                return;

            s_showMenu = show;

            if (CanvasRoot)
            {
                CanvasRoot.SetActive(show);

                if (show)
                    CursorUnlocker.SetEventSystem();
                else
                    CursorUnlocker.ReleaseEventSystem();
            }

            CursorUnlocker.UpdateCursorControl();
        }

        public static void Update()
        {
            if (InputManager.GetKeyDown(ExplorerConfig.Instance.Main_Menu_Toggle))
                ShowMenu = !ShowMenu;

            if (!ShowMenu || !s_doneUIInit || !CanvasRoot)
                return;

            MainMenu.Instance?.Update();

            if (EventSys)
            {
                if (EventSystem.current != EventSys)
                    CursorUnlocker.SetEventSystem();
#if CPP
                // Some IL2CPP games behave weird with multiple UI Input Systems, some fixes for them.
                var evt = InputManager.InputPointerEvent;
                if (evt != null)
                {
                    if (!evt.eligibleForClick && evt.selectedObject)
                        evt.eligibleForClick = true;
                }
#endif
            }

            if (PanelDragger.Instance != null)
                PanelDragger.Instance.Update();

            for (int i = 0; i < SliderScrollbar.Instances.Count; i++)
            {
                var slider = SliderScrollbar.Instances[i];

                if (slider.CheckDestroyed())
                    i--;
                else
                    slider.Update();
            }

            for (int i = 0; i < InputFieldScroller.Instances.Count; i++)
            {
                var input = InputFieldScroller.Instances[i];

                if (input.CheckDestroyed())
                    i--;
                else
                    input.Update();
            }
        }

        private static void LoadBundle()
        {
            AssetBundle bundle = null;

            try
            {
                bundle = LoadExplorerUi("modern");
                if (bundle == null)
                    throw new Exception();
            }
            catch
            {
                ExplorerCore.Log("Failed to load Unity 2017 ExplorerUI Bundle, falling back to legacy");

                try
                {
                    bundle = LoadExplorerUi("legacy");
                }
                catch
                {
                    // ignored
                }
            }

            if (bundle == null)
            {
                ExplorerCore.LogWarning("Could not load the ExplorerUI Bundle!");
                ConsoleFont = Resources.GetBuiltinResource<Font>("Arial.ttf");
                return;
            }

            BackupShader = bundle.LoadAsset<Shader>("DefaultUI");

            // Fix for games which don't ship with 'UI/Default' shader.
            if (Graphic.defaultGraphicMaterial.shader?.name != "UI/Default")
            {
                ExplorerCore.Log("This game does not ship with the 'UI/Default' shader, using manual Default Shader...");
                Graphic.defaultGraphicMaterial.shader = BackupShader;
            }

            //ResizeCursor = bundle.LoadAsset<Sprite>("cursor");

            ConsoleFont = bundle.LoadAsset<Font>("CONSOLA");

            ExplorerCore.Log("Loaded UI bundle");
        }

        private static AssetBundle LoadExplorerUi(string id)
        {
            var data = ReadFully(typeof(ExplorerCore).Assembly.GetManifestResourceStream($"UnityExplorer.Resources.explorerui.{id}.bundle"));
            return AssetBundle.LoadFromMemory(data);
        }

        private static byte[] ReadFully(this Stream input)
        {
            using (var ms = new MemoryStream())
            {
                byte[] buffer = new byte[81920];
                int read;
                while ((read = input.Read(buffer, 0, buffer.Length)) != 0)
                    ms.Write(buffer, 0, read);
                return ms.ToArray();
            }
        }
    }
}