using System;
using UnityEngine;
using UnityEngine.UI;

public class LevelSystem : MonoBehaviour
{
    [Header("Progression")]
    public int level = 1;
    public int currentExp = 0;
    public int expToNextLevel = 100;

    [Header("Dependencies")]
    public TalentManager talentManager;
    public NotificationUI notificationUI;

    [Header("HUD")]
    public Text levelText;
    public Text expText;
    public Image expFillImage;

    public event Action OnExperienceChanged;
    public event Action OnLevelChanged;

    private void Awake()
    {
        if (talentManager == null)
        {
            talentManager = FindObjectOfType<TalentManager>();
        }

        if (notificationUI == null)
        {
            notificationUI = FindObjectOfType<NotificationUI>();
        }
    }

    private void Start()
    {
        RefreshUI();
    }

    private void Update()
    {
        if (Input.GetKeyDown(KeyCode.X))
        {
            AddExperience(50);
        }
    }

    public void AddExperience(int amount)
    {
        if (amount <= 0)
        {
            return;
        }

        currentExp += amount;
        Notify($"Получено опыта: {amount}");

        while (currentExp >= expToNextLevel)
        {
            currentExp -= expToNextLevel;
            LevelUp();
        }

        RefreshUI();
        OnExperienceChanged?.Invoke();
    }

    public void LevelUp()
    {
        level = Mathf.Max(1, level + 1);
        expToNextLevel = Mathf.Max(1, Mathf.RoundToInt(expToNextLevel * 1.25f + 25f));

        if (talentManager != null)
        {
            talentManager.AddTalentPoints(1);
        }

        Notify($"Уровень {level}! Получено очко талантов");
        RefreshUI();
        OnLevelChanged?.Invoke();
    }

    public float GetExpNormalized()
    {
        if (expToNextLevel <= 0)
        {
            return 0f;
        }

        return Mathf.Clamp01((float)currentExp / expToNextLevel);
    }

    private void RefreshUI()
    {
        if (levelText != null)
        {
            levelText.text = $"Уровень {level}";
        }

        if (expText != null)
        {
            expText.text = $"{currentExp} / {expToNextLevel} XP";
        }

        if (expFillImage != null)
        {
            expFillImage.fillAmount = GetExpNormalized();
        }
    }

    private void Notify(string message)
    {
        if (notificationUI != null)
        {
            notificationUI.Show(message);
        }
    }
}