using UnityEngine;

namespace Cielonos.MainGame.Effects
{
    /// <summary>
    /// 单个残影个体生命周期与渐隐控制器。
    /// </summary>
    public class AfterImageItem : MonoBehaviour
    {
        private MeshRenderer[] renderers;
        private MaterialPropertyBlock propBlock;
        private float fadeSpeed;
        private float currentFade = 1f;

        public void Initialize(MeshFilter[] filters, MeshRenderer[] renderers, Material afterImageMat, float duration)
        {
            this.renderers = renderers;
            this.fadeSpeed = 1f / duration;
            this.propBlock = new MaterialPropertyBlock();

            foreach (var renderer in renderers)
            {
                if (renderer != null)
                {
                    renderer.sharedMaterial = afterImageMat;
                }
            }
        }

        private void Update()
        {
            currentFade -= Time.deltaTime * fadeSpeed;
            if (currentFade <= 0f)
            {
                // 必须手动销毁运行时烘焙出的 Mesh 资源，防止显存泄漏 (GC 不会自动回收 BakeMesh 产生的网格)
                foreach (var filter in GetComponentsInChildren<MeshFilter>())
                {
                    if (filter != null && filter.sharedMesh != null)
                    {
                        Destroy(filter.sharedMesh);
                    }
                }
                Destroy(gameObject);
                return;
            }

            propBlock.SetFloat("_Fade", currentFade);
            foreach (var renderer in renderers)
            {
                if (renderer != null)
                {
                    renderer.SetPropertyBlock(propBlock);
                }
            }
        }
    }
}