using System;
using System.Threading;
using BITKit.Mod;
using Cysharp.Threading.Tasks;
using UnityEngine.UIElements;
// ReSharper disable MemberCanBePrivate.Global

namespace BITKit.UX
{
    public abstract class UIToolkitOverlay:IDisposable
    {
        protected readonly CancellationTokenSource CancellationToken;
        protected readonly IUXService UXService;
        protected VisualElement RootVisualElement { get; set; }
        protected bool IsInitialized { get; private set; }
        protected readonly UniTaskCompletionSource WaitUntilInitialized = new();
        protected UIToolkitOverlay(IUXService uxService, CancellationTokenSource cancellationToken)
        {
            UXService = uxService;
            CancellationToken = cancellationToken;
            CancellationToken.Token.Register(Dispose);
        }
        protected abstract string DocumentPath { get; }
        // ReSharper disable once MemberCanBeProtected.Global
        public virtual async UniTask InitializeAsync()
        {
            if(IsInitialized)return;
            var asset =await ModService.LoadAsset<VisualTreeAsset>(DocumentPath);
            var root= RootVisualElement = UXService.Root.As<VisualElement>().Create(asset);
            
            RootVisualElement.BringToFront();
            
            RootVisualElement.name = GetType().Name;
            RootVisualElement.pickingMode = PickingMode.Ignore;

            root.style.position = Position.Absolute;
            root.style.top = 0;
            root.style.bottom = 0;
            root.style.left = 0;
            root.style.right = 0;
            
            UXUtils.Inject(this);
            IsInitialized = true;

            WaitUntilInitialized.TrySetResult();
        }
        public virtual void Dispose()
        {
            if(RootVisualElement is null)return;
            IsInitialized = false;
            RootVisualElement.RemoveFromHierarchy();
            RootVisualElement = null;
        }
    }

}