using System.Collections.Generic;
using UnityEngine;

namespace AlicizaX.UI.Runtime
{
    internal sealed partial class UIManager
    {
        public Camera UICamera { get; set; }
        public Canvas UICanvas;
        public Transform UICanvasRoot { get; set; }
        public Transform UIRoot;

        private const int RootPosOffset = 1000;
        private const int LayerDistance = 1000;

        private const int LAYER_DEEP = 2000;
        private const int WINDOW_DEEP = 100;

        private readonly RectTransform[] m_AllWindowLayer = new RectTransform[(int)UILayer.All];

        #region 快捷获取层级

        private RectTransform m_UICache;

        public RectTransform UICache
        {
            get
            {
                if (m_UICache == null)
                {
                    m_UICache = GetLayerRect(UILayer.Cache);
                }

                return m_UICache;
            }
        }

        private RectTransform m_UIPanel;

        public RectTransform UIPanel
        {
            get
            {
                if (m_UIPanel == null)
                {
                    m_UIPanel = GetLayerRect(UILayer.UI);
                }

                return m_UIPanel;
            }
        }

        #endregion

        public void Initlize(Transform root)
        {
            UIRoot = root;
            Object.DontDestroyOnLoad(root.gameObject);

            UIRoot.transform.position = new Vector3(RootPosOffset, RootPosOffset, 0);

            UICanvas = UIRoot.GetComponentInChildren<Canvas>();
            UICamera = UICanvas.worldCamera;
            UICanvasRoot = UICanvas.transform;


            const int len = (int)UILayer.All;
            for (var i = len - 1; i >= 0; i--)
            {
                var layer = new GameObject($"Layer{i}-{(UILayer)i}");
                var rect = layer.AddComponent<RectTransform>();
                rect.SetParent(UICanvasRoot);
                rect.localScale = Vector3.one;
                rect.pivot = new Vector2(0.5f, 0.5f);
                rect.anchorMax = Vector2.one;
                rect.anchorMin = Vector2.zero;
                rect.sizeDelta = Vector2.zero;
                rect.localRotation = Quaternion.identity;
                rect.localPosition = new Vector3(0, 0, i * LayerDistance);
                m_AllWindowLayer[i] = rect;
                mShowUIWindow.Add((UILayer)i, new List<PanelInfo>(16));
                //算上持续缓存的 感觉一个层级 不可能同时有16个界面驻留吧??分层做处理也可以
            }

            InitAddUIBlock();
        }


        public RectTransform GetLayerRect(UILayer panelLayer)
        {
            return m_AllWindowLayer[(int)panelLayer];
        }
    }
}