using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UIElements;
using UnityEngine.Events;
using Sirenix.OdinInspector;
using Cysharp.Threading.Tasks;
using System.Threading;
namespace BITKit.UX
{
    public abstract class UXElement : Provider, IProvider<bool>, IActivable, IEnabled
    {
        protected bool isActive = true;
        public virtual bool Get() => isActive;
        public virtual void Set(bool active) { }
        public virtual void OnStart() { }
        public override void Set<T>(T obj)
        {
            (this as IProvider<T>).Set(obj);
        }
        public virtual void SetActive(bool active)
        {
            GetVisualElement().SetActive(active);
        }

        public virtual void SetPosition(Vector3 worldPosition)
        {
            if (Camera.main != null)
            {
                var cameraTrans = Camera.main.transform;
                var visualElement = GetVisualElement();
                var pos = RuntimePanelUtils
                    .CameraTransformWorldToPanel(visualElement.panel, worldPosition, Camera.main);
                pos.x = (pos.x - visualElement.layout.width / 2);

                Rect elementRect = new()
                {
                    position = pos,
                    size = visualElement.layout.size,
                };
            
                visualElement.style.left = 0;
                visualElement.style.top = 0;
                visualElement.style.position = Position.Absolute;
                visualElement.transform.position = pos;
                visualElement.SetOpacity(Vector3.Dot(cameraTrans.forward, worldPosition - cameraTrans.position) > 0 ? 1 : 0);
            }
        }
        public virtual VisualElement GetVisualElement() => null;

        public virtual bool IsEnabled()
        {
            return GetVisualElement().enabledSelf;
        }
        public virtual void SetEnabled(bool enabled)
        {
            GetVisualElement().SetEnabled(enabled);
        }
    }
    public abstract class UXElement<UX> : UXElement, IProvider<UX> where UX : VisualElement
    {
        public static implicit operator UX(UXElement<UX> self)
        {
            return self.visualElement;
        }
        [Header(Constant.Header.Components)]
        public UIDocument document;
        [Header(Constant.Header.Settings)]
        public string bindName;
        [SerializeField, SerializeReference, SubclassSelector]
        IReference bindNameProvider = new GetNameFromGameobject();
        [Header(Constant.Header.InternalVariables)]
        private UX m_visualElement;
        protected IStyle style => visualElement.style;
        public UX visualElement
        {
            get
            {
                if (m_visualElement is null)
                {
                    var bindName = this.bindName;
                    if (string.IsNullOrEmpty(bindName))
                    {
                        bindName = bindNameProvider.Get();
                    }
                    var split = bindName.Split(@".");
                    var visualElement = document.rootVisualElement;
                    foreach (var name in split)
                    {
                        try
                        {
                            visualElement = visualElement.Q(name);
                        }
                        catch (System.Exception)
                        {
                            Debug.LogWarning(name);
                            throw;
                        }
                    }
                    m_visualElement = visualElement as UX;

                    if (m_visualElement is null)
                    {
                        Debug.LogWarning(bindName);
                    }
                }
                return m_visualElement;
            }
        }

        public override bool Get() => isActive;
        public override VisualElement GetVisualElement() => visualElement;
        protected CancellationToken cancellationToken;
        public override async void Set(bool active)
        {
            await UniTask.SwitchToMainThread(cancellationToken);
            visualElement.SetEnabled(active);
            if (active != isActive)
            {
                isActive = active;
                visualElement.SetEnabled(active);
            }
        }
        void Awake()
        {
            cancellationToken = gameObject.GetCancellationTokenOnDestroy();
            OnStart();
        }
        void OnValidate()
        {
            if (bindNameProvider is GetNameFromGameobject x)
            {
                x.gameobject = gameObject;
            }
            if (document is null)
            {
                document = GetComponentInParent<UIDocument>();
            }
        }
        UX IProvider<UX>.Get() => visualElement;
        public override T Get<T>()
        {
            if (visualElement is T t)
            {
                return t;
            }
            return base.Get<T>();
        }
        public void Set(UX t)
        {
            var root = visualElement.parent;
            root.Remove(visualElement);
            root.Add(t);
            m_visualElement = t;
        }
        protected virtual void OnVistualElementDisabled()
        {

        }
        public void AddToClassList(string className)
        {
            visualElement.AddToClassList(className);
        }
        public void RemoveFromClassList(string className)
        {
            visualElement.RemoveFromClassList(className);
        }
    }
}