using System;
using System.Runtime.CompilerServices;
using AlicizaX.Runtime;

namespace AlicizaX.UI.Runtime
{
    public sealed class UIMetadata
    {
        public UIBase View { get; private set; }
        public EUIResLoadType LoadType;
        public readonly int UILayer;
        public readonly bool FullScreen;
        public string ResLocation;
        public readonly int CacheTime;
        public readonly Type UILogicType;

        public bool InCache = false;
        public readonly RuntimeTypeHandle RuntimeTypeHandle;

        private int NotFlag = 0;

        public UIState State
        {
            get
            {
                if (View == null) return UIState.Uninitialized;
                return View.State;
            }
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public void CreateUI()
        {
            if (View is null)
            {
                View = (UIBase)Activator.CreateInstance(UILogicType);
            }

            LoadUIAttribute();
        }

        public void Dispose()
        {
            if (State != UIState.Uninitialized)
            {
                View.InternalDestroy();
                View = null;
            }
        }

        public UIMetadata(Type uiType, UILayer layer, bool fullScreen, int cacheTime)
        {
            UILogicType = uiType;
            UILayer = (int)layer;
            FullScreen = fullScreen;
            CacheTime = cacheTime;
            RuntimeTypeHandle = uiType.TypeHandle;
        }

        public UIMetadata(Type uiType)
        {
            UILogicType = uiType;
            RuntimeTypeHandle = uiType.TypeHandle;
        }

        private void LoadUIAttribute()
        {
            if (NotFlag == 0)
            {
                NotFlag = 1;
                UIResAttribute resAttribute = Attribute.GetCustomAttribute(View.UIHolderType, typeof(UIResAttribute)) as UIResAttribute;
                if (resAttribute == null)
                    throw new GameFrameworkException($"UIHolder: {View.UIHolderType.FullName} UIResAttribute can be null.");
                ResLocation = resAttribute.ResLocation;
                LoadType = resAttribute.ResLoadType;
            }
        }
    }
}