using UnityEngine;
using UnityEngine.UI;
using System.Collections;

/// <summary>
/// 金币 UI 显示，显示在屏幕右上角
/// </summary>
[RequireComponent(typeof(Text))]
public class GoldUI : MonoBehaviour
{
    private Text goldText;
    private bool isSubscribed = false;

    private void Awake()
    {
        goldText = GetComponent<Text>();
    }

    private void Start()
    {
        // 延迟订阅，确保 GoldManager 已初始化
        StartCoroutine(SubscribeToGoldManager());
    }

    private IEnumerator SubscribeToGoldManager()
    {
        // 等待 GoldManager 初始化
        while (GoldManager.Instance == null)
        {
            yield return null;
        }

        // 订阅事件
        GoldManager.Instance.OnGoldChanged += UpdateGoldDisplay;
        isSubscribed = true;

        // 立即更新显示
        UpdateGoldDisplay(GoldManager.Instance.CurrentGold);
    }

    private void OnDestroy()
    {
        // 取消订阅
        if (isSubscribed && GoldManager.Instance != null)
        {
            GoldManager.Instance.OnGoldChanged -= UpdateGoldDisplay;
        }
    }

    private void UpdateGoldDisplay(int newGold)
    {
        if (goldText != null)
        {
            goldText.text = $"金币: {newGold}";
        }
    }
}