using UnityEngine;

namespace Gameplay.PostProcess.BlackArea
{
    public class LightPoint
    {
        public bool isLight;
        public int cellIndex;
        public float remainTime;

        private MeshRenderer _meshRenderer;
        private readonly GameObject _lightObj;
        
        private static MaterialPropertyBlock _cacheMatBlock;
        private static readonly int Alpha = Shader.PropertyToID("_Alpha");

        private float _currentAlpha;
        private const float LIGHT_UP_SPEED = 5F;
        private const float LIGHT_OFF_SPEED = 5F;

        public LightPoint(int cellIndex, GameObject lightObj)
        {
            if (_cacheMatBlock == null)
            {
                _cacheMatBlock = new MaterialPropertyBlock();
            }
            this.cellIndex = cellIndex;
            _lightObj = lightObj;
            isLight = false;
            remainTime = 0f;

            var meshTrans = _lightObj.transform.GetChild(0);
            _meshRenderer = meshTrans.GetComponent<MeshRenderer>();
            _currentAlpha = 0;
            _cacheMatBlock.SetFloat(Alpha, _currentAlpha);
            _meshRenderer.SetPropertyBlock(_cacheMatBlock);
        }

        public void LightUp()
        {
            isLight = true;
            // _lightObj.SetActive(true);
        }

        public void LightOff()
        {
            isLight = false;
            // _lightObj.SetActive(false);
        }

        public void MarkLight(float duringTime)
        {
            remainTime = Mathf.Max(duringTime, remainTime);
            if (!isLight)
            {
                LightUp();
            }
        }

        public void LogicUpdate(float dt)
        {
            if (isLight)
            {
                if (_currentAlpha < 1)
                {
                    _currentAlpha += dt * LIGHT_UP_SPEED;
                    _currentAlpha = Mathf.Min(1, _currentAlpha);
                    _cacheMatBlock.SetFloat(Alpha, _currentAlpha);
                    _meshRenderer.SetPropertyBlock(_cacheMatBlock);
                }
                remainTime -= dt;
                if (remainTime < 0)
                {
                    LightOff();
                }
            }
            else
            {
                if (_currentAlpha > 0)
                {
                    _currentAlpha -= dt * LIGHT_OFF_SPEED;
                    _currentAlpha = Mathf.Max(0, _currentAlpha);
                    _cacheMatBlock.SetFloat(Alpha, _currentAlpha);
                    _meshRenderer.SetPropertyBlock(_cacheMatBlock);
                }
            }
        }
    }
}