using System;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;

/// <summary>
/// Toggle 长按检测器:挂在 Toggle 同一个物体上。
/// - 短按:不干预,Toggle 自己正常翻转(走原有 onValueChanged 逻辑)
/// - 长按(按住超过 longPressTime):触发一次 onLongPress,并吞掉松手时的 Toggle 翻转
///   (松手瞬间 Toggle 的 OnPointerClick 因 interactable=false 不会翻转 isOn,下一帧恢复)
/// 用法:面板 Start 里 AddComponent 到目标 Toggle 上并订阅 onLongPress。
/// </summary>
public class ToggleLongPress : MonoBehaviour, IPointerDownHandler, IPointerUpHandler
{
    [Tooltip("长按判定时间(秒):按住超过此时间触发 onLongPress,提前松手不触发")]
    public float longPressTime = 0.6f;

    /// <summary>长按达到阈值时触发一次(提前松手不触发)</summary>
    public event Action onLongPress;

    private Toggle _toggle;
    private bool _pressing;
    private float _timer;
    private bool _fired;
    private bool _restoreInteractable;

    private void Awake()
    {
        _toggle = GetComponent<Toggle>();
    }

    private void Update()
    {
        if (_pressing)
        {
            _timer += Time.deltaTime;
            if (_timer >= longPressTime && !_fired)
            {
                _fired = true;
                _pressing = false;

                // ⭐ 吞掉松手时的 Toggle 翻转:Toggle.InternalToggle 检查 IsInteractable,
                //   置 false 后 OnPointerClick 不会翻转 isOn;下一帧恢复
                if (_toggle != null && _toggle.interactable)
                {
                    _toggle.interactable = false;
                    _restoreInteractable = true;
                }

                onLongPress?.Invoke();
            }
        }
        else if (_restoreInteractable && _toggle != null)
        {
            // 长按吞掉翻转后,下一帧恢复 interactable
            _toggle.interactable = true;
            _restoreInteractable = false;
        }
    }

    public void OnPointerDown(PointerEventData eventData)
    {
        if (eventData.button != PointerEventData.InputButton.Left) return;
        _pressing = true;
        _timer = 0f;
        _fired = false;
    }

    public void OnPointerUp(PointerEventData eventData)
    {
        _pressing = false;
        _timer = 0f;
        // 提前松手(未达长按阈值) → 不干预,Toggle 自己处理点击翻转
    }
}