Assets/Scripts/UIManager.cs

using UnityEngine;
using UnityEngine.UI;
using TMPro;

namespace UnityAgent
{
    /// <summary>
    /// Lightweight HUD manager using Unity UI + TextMeshPro. Exposes methods
    /// for other systems to update score / health / messages.
    /// </summary>
    public class UIManager : MonoBehaviour
    {
        public static UIManager Instance { get; private set; }

        [Header("HUD")]
        public TMP_Text scoreText;
        public TMP_Text healthText;
        public TMP_Text messageText;
        public Image healthBarFill;

        [Header("Message")]
        public float messageDuration = 2f;

        private float _messageTimer;

        private void Awake()
        {
            if (Instance != null && Instance != this) { Destroy(gameObject); return; }
            Instance = this;
            SetMessage(string.Empty);
        }

        private void Update()
        {
            if (_messageTimer > 0f)
            {
                _messageTimer -= Time.deltaTime;
                if (_messageTimer <= 0f && messageText != null) messageText.text = string.Empty;
            }
        }

        public void SetScore(int score)
        {
            if (scoreText != null) scoreText.text = $"Score: {score}";
        }

        public void SetHealth(float current, float max)
        {
            if (healthText != null) healthText.text = $"HP: {Mathf.CeilToInt(current)} / {Mathf.CeilToInt(max)}";
            if (healthBarFill != null) healthBarFill.fillAmount = Mathf.Clamp01(current / max);
        }

        public void SetMessage(string msg)
        {
            if (messageText != null) messageText.text = msg;
            _messageTimer = string.IsNullOrEmpty(msg) ? 0f : messageDuration;
        }
    }
}