using UnityEngine;
using TMPro;
using UnityEngine.UI;
using UnityEngine.SceneManagement;

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

    [Header("HUD Elements")]
    [SerializeField] private Slider healthBar;
    [SerializeField] private TextMeshProUGUI ammoText;
    [SerializeField] private TextMeshProUGUI zombieCountText;
    [SerializeField] private TextMeshProUGUI notificationText;
    [SerializeField] private GameObject gameOverPanel;

    private void Awake()
    {
        if (Instance != null && Instance != this)
        {
            Destroy(gameObject);
        }
        else
        {
            Instance = this;
        }
    }

    private void Start()
    {
        if (PlayerHealthController.Instance != null)
        {
            PlayerHealthController.Instance.OnHealthChanged += UpdateHealthBar;
            UpdateHealthBar(PlayerHealthController.Instance.CurrentHealth, PlayerHealthController.Instance.MaxHealth);
        }

        if (gameOverPanel != null)
        {
            gameOverPanel.SetActive(false);
        }
    }

    private void OnDestroy()
    {
        if (PlayerHealthController.Instance != null)
        {
            PlayerHealthController.Instance.OnHealthChanged -= UpdateHealthBar;
        }
    }

    public void UpdateHealthBar(int current, int max)
    {
        if (healthBar != null && max > 0)
        {
            healthBar.value = (float)current / max;
        }
    }

    public void UpdateAmmoDisplay(int current, int max)
    {
        if (ammoText != null)
        {
            ammoText.text = $"{current} / {max}";
        }
    }

    public void UpdateZombiesRemaining(int count)
    {
        if (zombieCountText != null)
        {
            zombieCountText.text = $"Zombies Left: {count}";
        }
    }

    public void ShowNotification(string message)
    {
        if (notificationText != null)
        {
            notificationText.text = message;
            CancelInvoke(nameof(ClearNotification));
            Invoke(nameof(ClearNotification), 4f);
        }
    }

    private void ClearNotification()
    {
        if (notificationText != null)
        {
            notificationText.text = "";
        }
    }

    public void ShowGameOverScreen()
    {
        if (gameOverPanel != null)
        {
            gameOverPanel.SetActive(true);
            Cursor.lockState = CursorLockMode.None;
            Cursor.visible = true;
        }
    }

    public void RestartCurrentScene()
    {
        SceneManager.LoadScene(SceneManager.GetActiveScene().name);
    }
}