using UnityEngine;
using UnityEngine.UI;

/// <summary>
/// GraphicRaycaster 管理器，负责管理UI的射线检测功能
/// 使用组合模式，从UIWindow中提取出GraphicRaycaster管理功能
/// </summary>
public class GraphicRaycasterManager
{
    private GameObject _rootGameObject;
    private int _disableGraphicRaycasterCount;

    /// <summary>
    /// 构造函数
    /// </summary>
    /// <param name="rootGameObject">需要管理GraphicRaycaster的根GameObject</param>
    public GraphicRaycasterManager(GameObject rootGameObject)
    {
        _rootGameObject = rootGameObject;
        _disableGraphicRaycasterCount = 0;
    }

    /// <summary>
    /// 是否启用GraphicRaycaster
    /// </summary>
    public bool IsEnableGraphicRaycaster
    {
        get { return _disableGraphicRaycasterCount <= 0; }
        set
        {
            if (value)
            {
                if (_disableGraphicRaycasterCount > 0)
                    --_disableGraphicRaycasterCount;
            }
            else
                ++_disableGraphicRaycasterCount;

            if (null == _rootGameObject)
                return;

            UpdateGraphicRaycasterState();
        }
    }

    /// <summary>
    /// 更新GraphicRaycaster状态
    /// </summary>
    private void UpdateGraphicRaycasterState()
    {
        bool isEnabled = _disableGraphicRaycasterCount <= 0;

        if (null == _rootGameObject)
            return;

        // 确保根对象有GraphicRaycaster组件
        if (!_rootGameObject.TryGetComponent(out GraphicRaycaster graphicRaycaster))
            graphicRaycaster = _rootGameObject.AddComponent<GraphicRaycaster>();

        if (null != graphicRaycaster)
            graphicRaycaster.enabled = isEnabled;

        // 更新所有子对象的GraphicRaycaster
        GraphicRaycaster[] graphicRaycasters = _rootGameObject.GetComponentsInChildren<GraphicRaycaster>();
        foreach (GraphicRaycaster gr in graphicRaycasters)
        {
            if (null == gr)
                continue;

            gr.enabled = isEnabled;
        }
    }

    /// <summary>
    /// 获取当前禁用计数
    /// </summary>
    /// <returns>禁用计数</returns>
    public int GetDisableCount()
    {
        return _disableGraphicRaycasterCount;
    }

    /// <summary>
    /// 重置禁用计数
    /// </summary>
    public void ResetDisableCount()
    {
        _disableGraphicRaycasterCount = 0;
        UpdateGraphicRaycasterState();
    }

    /// <summary>
    /// 强制启用GraphicRaycaster
    /// </summary>
    public void ForceEnable()
    {
        _disableGraphicRaycasterCount = 0;
        UpdateGraphicRaycasterState();
    }

    /// <summary>
    /// 强制禁用GraphicRaycaster
    /// </summary>
    public void ForceDisable()
    {
        _disableGraphicRaycasterCount = 1;
        UpdateGraphicRaycasterState();
    }
}