using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.SceneManagement;

public class PlayerHealth : Singleton<PlayerHealth>
{
    public bool isDead { get; private set; }

    [SerializeField] private int maxHealth = 3;
    [SerializeField] private float knockBackThrustAmount = 10f;
    [SerializeField] private float damageRecoveryTime = 1f;

    private Slider healthSlider;
    private int currentHealth;
    private bool canTakeDamage = true;
    private Knockback knockback;
    private Flash flash;

    const string HEALTH_SLIDER_TEXT = "Health Slider";
    const string TOWN_TEXT = "Scene1";
    readonly int DEATH_HASH = Animator.StringToHash("Death");

    protected override void Awake() {
        base.Awake();

        flash = GetComponent<Flash>();
        knockback = GetComponent<Knockback>();
    }

    private void Start() {
        isDead = false;
        currentHealth = maxHealth;

        UpdateHealthSlider();
    }

    private void OnCollisionStay2D(Collision2D other) {
        EnemyAI enemy = other.gameObject.GetComponent<EnemyAI>();

        if (enemy) {
            TakeDamage(1, other.transform);
        }
    }

    public void HealPlayer() {
        if (currentHealth < maxHealth) {
            currentHealth += 1;
            UpdateHealthSlider();
        }
    }

    public void TakeDamage(int damageAmount, Transform hitTransform) {
        if (!canTakeDamage) { return; }

        ScreenShakeManager.Instance.ShakeScreen();
        knockback.GetKnockedBack(hitTransform, knockBackThrustAmount);
        StartCoroutine(flash.FlashRoutine());
        canTakeDamage = false;
        currentHealth -= damageAmount;
        StartCoroutine(DamageRecoveryRoutine());
        UpdateHealthSlider();
        CheckIfPlayerDeath();
    }

    private void CheckIfPlayerDeath() {
        if (currentHealth <= 0 && !isDead) {
            isDead = true;
            Destroy(ActiveWeapon.Instance.gameObject);
            currentHealth = 0;
            GetComponent<Animator>().SetTrigger(DEATH_HASH);
            
            // Reset gold when the player dies
            EconomyManager.Instance.ResetGold();
            
            StartCoroutine(DeathLoadSceneRoutine());
        }
    }

    private IEnumerator DeathLoadSceneRoutine() {
        yield return new WaitForSeconds(2f);
        Destroy(gameObject);
        SceneManager.LoadScene(TOWN_TEXT);
    }

    private IEnumerator DamageRecoveryRoutine() {
        yield return new WaitForSeconds(damageRecoveryTime);
        canTakeDamage = true;
    }

    private void UpdateHealthSlider() {
        if (healthSlider == null) {
            healthSlider = GameObject.Find(HEALTH_SLIDER_TEXT).GetComponent<Slider>();
        }

        healthSlider.maxValue = maxHealth;
        healthSlider.value = currentHealth;
    }
}