using System;
using System.Collections;
using RR.Common.Utility;
using UnityEngine;

namespace RR.Game2D.Entities
{
    public class TransparentForeground : MonoBehaviour
    {
        [SerializeField] private float fadeDuration = 0.25f;
        [SerializeField, Range(0, 255)] private float targetAlpha = 100f;

        private const float STARTING_ALPHA = 255f;
        private Collider2D _collider;
        private SpriteRenderer[] _spriteRenderers;

        private void Awake()
        {
            _collider = GetComponent<Collider2D>();
            if (!_collider.isTrigger) _collider.isTrigger = true;
            _spriteRenderers = GetComponentsInChildren<SpriteRenderer>();

            if (_collider == null)
                Debug.LogWarning($"[{nameof(TransparentForeground)}] Collider2D не найден на {gameObject.name}.");

            if (_spriteRenderers == null || _spriteRenderers.Length == 0)
                Debug.LogWarning($"[{nameof(TransparentForeground)}] SpriteRenderer'ы не найдены на {gameObject.name} и его дочерних объектах.");

            if (_spriteRenderers == null) return;
            
            float initialAlpha = MathUtils.Remap(STARTING_ALPHA, 0f, 255f, 0f, 1f);
            
            foreach (SpriteRenderer spriteRenderer in _spriteRenderers)
            {
                if (!Mathf.Approximately(spriteRenderer.color.a, initialAlpha))
                {
                    spriteRenderer.color = new Color(spriteRenderer.color.r, spriteRenderer.color.g, spriteRenderer.color.b,
                        initialAlpha);
                }
            }
        }

        private void OnTriggerEnter2D(Collider2D other)
        {
            if (!other.CompareTag("Player")) return;
            StopAllCoroutines();
            StartCoroutine(Fade(targetAlpha));
        }

        private void OnTriggerExit2D(Collider2D other)
        {
            if (!other.CompareTag("Player")) return;
            StopAllCoroutines();
            StartCoroutine(Fade(STARTING_ALPHA));
        }

        private IEnumerator Fade(float targetFadeAlpha)
        {
            float elapsed = 0f;
            float targetAlphaNormalized = MathUtils.Remap(targetFadeAlpha, 0f, 255f, 0f, 1f);
            
            // Сохраняем начальные цвета всех спрайтов
            Color[] initialColors = new Color[_spriteRenderers.Length];
            Color[] targetColors = new Color[_spriteRenderers.Length];
            
            for (int i = 0; i < _spriteRenderers.Length; i++)
            {
                initialColors[i] = _spriteRenderers[i].color;
                targetColors[i] = new Color(initialColors[i].r, initialColors[i].g, initialColors[i].b, targetAlphaNormalized);
            }

            // Интерполируем все спрайты одновременно
            while (elapsed < fadeDuration)
            {
                elapsed += Time.deltaTime;
                float t = elapsed / fadeDuration;
                
                for (int i = 0; i < _spriteRenderers.Length; i++)
                {
                    _spriteRenderers[i].color = Color.Lerp(initialColors[i], targetColors[i], t);
                }
                
                yield return null;
            }

            // Устанавливаем финальные значения
            for (int i = 0; i < _spriteRenderers.Length; i++)
            {
                _spriteRenderers[i].color = targetColors[i];
            }
        }
    }
}