using UnityEngine;

public class FlipbookAnimationStarter : MonoBehaviour
{
    [Header("设置")]
    [Tooltip("是否在OnEnable时自动设置StartTime")]
    public bool autoSetOnEnable = true;

    [Tooltip("使用 MaterialPropertyBlock（推荐，支持GPU Instancing）还是Material实例")]
    public bool usePropertyBlock = true;

    [Tooltip("是否也处理子对象的Renderer")]
    public bool includeChildren = false;

    private static readonly int StartTimePropertyID = Shader.PropertyToID("_StartTime");
    private MaterialPropertyBlock _propertyBlock;
    private Renderer[] _renderers;

    private void Awake()
    {
        if (usePropertyBlock)
        {
            _propertyBlock = new MaterialPropertyBlock();
        }
        
        if (includeChildren)
        {
            _renderers = GetComponentsInChildren<Renderer>(true);
        }
        else
        {
            var renderer = GetComponent<Renderer>();
            _renderers = renderer != null ? new[] { renderer } : new Renderer[0];
        }
    }

    private void OnEnable()
    {
        if (autoSetOnEnable)
        {
            SetStartTime();
        }
    }

    public void SetStartTime()
    {
        SetStartTime(Time.time);
    }

    public void SetStartTime(float startTime)
    {
        foreach (var renderer in _renderers)
        {
            if (renderer == null) continue;

            if (usePropertyBlock)
            {
                renderer.GetPropertyBlock(_propertyBlock);
                _propertyBlock.SetFloat(StartTimePropertyID, startTime);
                renderer.SetPropertyBlock(_propertyBlock);
            }
            else
            {
                renderer.material.SetFloat(StartTimePropertyID, startTime);
            }
        }
    }

    public void ResetAnimation()
    {
        SetStartTime(0f);
    }

    public void RestartAnimation()
    {
        SetStartTime(Time.time);
    }

#if UNITY_EDITOR
    [ContextMenu("设置StartTime为当前时间")]
    private void EditorSetStartTime()
    {
        if (Application.isPlaying)
        {
            SetStartTime();
            Debug.Log($"已设置 {gameObject.name} 的StartTime为 {Time.time}");
        }
        else
        {
            Debug.LogWarning("请在运行时执行此操作");
        }
    }

    [ContextMenu("重置StartTime为0")]
    private void EditorResetStartTime()
    {
        if (Application.isPlaying)
        {
            ResetAnimation();
            Debug.Log($"已重置 {gameObject.name} 的StartTime为0");
        }
        else
        {
            Debug.LogWarning("请在运行时执行此操作");
        }
    }
#endif
}