using UnityEngine;
using System.Collections.Generic;
using TMPro;
using DG.Tweening; // cần DOTween

public class DamageTextManager : MonoBehaviour
{
    public static DamageTextManager Instance { get; private set; }

    [Header("Prefab")]
    [SerializeField] private TextMeshPro damageTextPrefab;

    [Header("Settings")]
    [SerializeField] private int poolSize = 20;
    [SerializeField] private Vector3 offset = new Vector3(0, 2f, 0);
    [SerializeField] private float riseDistance = 1.5f;
    [SerializeField] private float riseDuration = 0.8f;

    private readonly Queue<TextMeshPro> pool = new();

    private void Awake()
    {
        // Singleton
        if (Instance != null && Instance != this)
        {
            Destroy(gameObject);
            return;
        }
        Instance = this;
        DontDestroyOnLoad(gameObject);

        // Tạo sẵn pool
        for (int i = 0; i < poolSize; i++)
        {
            var textObj = Instantiate(damageTextPrefab, transform);
            textObj.gameObject.SetActive(false);
            pool.Enqueue(textObj);
        }
    }

    /// <summary>
    /// Gọi để spawn text damage
    /// </summary>
    public void ShowDamageText(Vector3 worldPos, int damage, Color color = default, float scale = 1f)
    {
        var text = GetFromPool();
        text.text = damage.ToString();
        text.color = color;
        text.fontSize = 6;
        text.transform.localScale = Vector3.one * scale;

        Vector3 startPos = worldPos + offset;
        text.transform.position = startPos;
        text.gameObject.SetActive(true);

        // Hiệu ứng bay lên + mờ dần
        text.transform.DOMoveY(startPos.y + riseDistance, riseDuration).SetEase(Ease.OutQuad);
        text.DOFade(0f, riseDuration)
            .SetEase(Ease.InQuad)
            .OnComplete(() =>
            {
                text.alpha = 1f;
                text.gameObject.SetActive(false);
                ReturnToPool(text);
            });
    }

    private TextMeshPro GetFromPool()
    {
        if (pool.Count > 0)
        {
            return pool.Dequeue();
        }

        // Nếu hết pool, tạo thêm
        var text = Instantiate(damageTextPrefab, transform);
        text.gameObject.SetActive(false);
        return text;
    }

    private void ReturnToPool(TextMeshPro text)
    {
        pool.Enqueue(text);
    }
}