using System;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.InputSystem;

[RequireComponent(typeof(UXButton))]
public sealed class InputGlyphUXButton : MonoBehaviour
{
    [SerializeField] private UXButton button;
    [SerializeField] private Image targetImage;
    private InputActionReference _actionReference;
    private InputDeviceWatcher.InputDeviceCategory _cachedCategory;
    private Sprite _cachedSprite;

#if UNITY_EDITOR
    /// <summary>
    /// 编辑器验证，自动获取 UXButton 组件
    /// </summary>
    private void OnValidate()
    {
        if (button == null)
        {
            button = GetComponent<UXButton>();
        }
    }
#endif

    /// <summary>
    /// 启用时初始化组件并订阅设备变更事件
    /// </summary>
    void OnEnable()
    {
        if (button == null) button = GetComponent<UXButton>();
        if (targetImage == null) targetImage = GetComponent<Image>();
        _actionReference = button.HotKeyRefrence;
        InputDeviceWatcher.OnDeviceChanged += OnDeviceChanged;
        _cachedCategory = InputDeviceWatcher.InputDeviceCategory.Keyboard;
        UpdatePrompt();
    }

    /// <summary>
    /// 禁用时取消订阅设备变更事件
    /// </summary>
    void OnDisable()
    {
        InputDeviceWatcher.OnDeviceChanged -= OnDeviceChanged;
    }

    /// <summary>
    /// 设备类型变更时的回调，更新图标显示
    /// </summary>
    void OnDeviceChanged(InputDeviceWatcher.InputDeviceCategory cat)
    {
        if (_cachedCategory != cat)
        {
            _cachedCategory = cat;
            UpdatePrompt();
        }
    }

    /// <summary>
    /// 更新按钮的输入提示图标
    /// </summary>
    void UpdatePrompt()
    {
        if (_actionReference == null || _actionReference.action == null || targetImage == null) return;

        // 使用缓存的设备类型，避免重复查询 CurrentCategory
        if (GlyphService.TryGetUISpriteForActionPath(_actionReference, "", _cachedCategory, out Sprite sprite))
        {
            if (_cachedSprite != sprite)
            {
                _cachedSprite = sprite;
                targetImage.sprite = sprite;
            }
        }
    }
}