using UnityEngine;
namespace Thousandto.Launcher.ExternalLibs
{
    [ExecuteInEditMode]
    public class FuncellShaderScript : MonoBehaviour
    {

        #region//可视变量
        [SerializeField, TooltipAttribute("高度雾正对光时的颜色")]
        private Color _heightFogSunColor = Color.white;
        private Color _heightFogSunColor_cache = Color.white;

        [SerializeField, TooltipAttribute("高度雾背光时的颜色")]
        private Color _heightFogColor = Color.blue;
        private Color _heightFogColor_cache = Color.blue;
       
        [SerializeField, TooltipAttribute("环境信息(x:高度Min,y:高度Max,z:近平面,w:远平面)")]
        private Vector4 _heightFogInfo = new Vector4(0f, 50f, 10f, 150f);
        private Vector4 _heightFogInfo_cache = Vector4.zero;

        [SerializeField, TooltipAttribute("玩家位置")]
        private Vector3 _playerPos = Vector3.zero;
        private Vector3 _playerPos_cache = Vector3.zero;

        [SerializeField, TooltipAttribute("玩家灯光的颜色,rgb表示光线颜色,其中a通道代表光线强度")]
        private Color _playerLightColor = Color.gray;
        private Color _playerLightColor_cache = Color.gray;

        [SerializeField, TooltipAttribute("是否使用玩家灯")]
        private bool _isUsePlayerLight = false;


        #endregion

        #region//其他内部变量
        //数据是否被改变
        private DirtyFlagCode _dataIsDirty = DirtyFlagCode.None;   
        //存储玩家位置信息的内存块
        private float[] _posBlock = null;
        #endregion
       
        #region//MonoBehaviour的方法
        private void Awake()
        {
            if (_heightFogSunColorPropID <= 0) BuildPropertyID();

            CacheShaderValue();
        }
        // Use this for initialization
        private void Start()
        {
            //启动起来先刷新一下
            _dataIsDirty = DirtyFlagCode.All;           
        }


        // Update is called once per frame
        private void Update()
        {
            if (_heightFogSunColorPropID <= 0)
            {
                BuildPropertyID();
            }

            RefreshPlayerPos();
            RefreshShaderValue();
        }


        private void OnDestroy()
        {
            ResetCacheShaderValue();
        }

        //当在编辑器状态下,值改变就会重新刷
        private void OnValidate()
        {

            if (_posBlock == null || _posBlock.Length < 3)
            {
                _posBlock = GonbestGMemory.AllocFloatBlock("PlayerPos", 3);
            }
            if (_posBlock != null && _posBlock.Length >= 3)
            {
                _posBlock[0] = _playerPos.x;
                _posBlock[1] = _playerPos.y;
                _posBlock[2] = _playerPos.z;
            }
            _dataIsDirty = DirtyFlagCode.All;
        }
        #endregion

        #region  //私有方法

        private void RefreshPlayerPos()
        {
            if (_isUsePlayerLight)
            {

                if (_posBlock == null || _posBlock.Length < 3)
                {
                    _posBlock = GonbestGMemory.AllocFloatBlock("PlayerPos", 3);
                }
                if (_posBlock != null && _posBlock.Length >= 3)
                {
                    if (Mathf.Abs(_playerPos.x - _posBlock[0]) > 0.001f
                        || Mathf.Abs(_playerPos.y - _posBlock[1]) > 0.001f
                        || Mathf.Abs(_playerPos.z - _posBlock[2]) > 0.001f)
                    {
                        _playerPos.x = _posBlock[0];
                        _playerPos.y = _posBlock[1];
                        _playerPos.z = _posBlock[2];
                        _dataIsDirty |= DirtyFlagCode.PlayerPos;
                    }

                }

            }
        }

        //缓存原始的Shader值
        private void CacheShaderValue()
        {
            _heightFogSunColor_cache = Shader.GetGlobalColor(_heightFogSunColorPropID);
            _heightFogColor_cache = Shader.GetGlobalColor(_heightFogColorPropID);
            _heightFogInfo_cache = Shader.GetGlobalVector(_heightFogInfoPropID);
            _playerPos_cache = Shader.GetGlobalVector(_playerPosPropID);
            _playerLightColor_cache = Shader.GetGlobalColor(_playerLightColorPropID);
            
            //_normalScale_cache = Shader.GetGlobalFloat(_normalScalePropID);
        }
        //恢复缓存的Shader值
        private void ResetCacheShaderValue()
        {
            Shader.SetGlobalColor(_heightFogSunColorPropID, _heightFogSunColor_cache);
            Shader.SetGlobalColor(_heightFogColorPropID, _heightFogColor_cache);
            Shader.SetGlobalVector(_heightFogInfoPropID, _heightFogInfo_cache);
            Shader.SetGlobalVector(_playerPosPropID, _playerPos_cache);
            Shader.SetGlobalColor(_playerLightColorPropID, _playerLightColor_cache);
        }

        // 角度转换为方向的函数
        private Vector4 AngleToForword(Vector3 angle)
        {
            return new Vector4(-Mathf.Cos(angle.x) * Mathf.Sin(angle.y), Mathf.Sin(angle.x), -Mathf.Cos(angle.x) * Mathf.Cos(angle.y), angle.z);
        }

        //刷新新的Shader值
        private void RefreshShaderValue()
        {
            if (_dataIsDirty != DirtyFlagCode.None)
            {
                //高度雾向光的颜色
                if (DirtyFlagCode.HeightFogSunColor == (_dataIsDirty & DirtyFlagCode.HeightFogSunColor))
                {
                    Shader.SetGlobalColor(_heightFogSunColorPropID, _heightFogSunColor);
                }
                //高度雾背光的颜色
                if (DirtyFlagCode.HeightFogColor == (_dataIsDirty & DirtyFlagCode.HeightFogColor))
                {
                    Shader.SetGlobalColor(_heightFogColorPropID, _heightFogColor);
                }
                
                //环境信息
                if (DirtyFlagCode.HeightFogInfo == (_dataIsDirty & DirtyFlagCode.HeightFogInfo))
                {
                    Shader.SetGlobalVector(_heightFogInfoPropID, _heightFogInfo);
                }
                //玩家信息
                if (DirtyFlagCode.PlayerPos == (_dataIsDirty & DirtyFlagCode.PlayerPos))
                {
                    Shader.SetGlobalVector(_playerPosPropID, _playerPos);
                }
                //设置玩家颜色
                if (DirtyFlagCode.PlayerLitColor == (_dataIsDirty & DirtyFlagCode.PlayerLitColor))
                {
                    Shader.SetGlobalColor(_playerLightColorPropID, _playerLightColor);
                }
               

                //是否使用角色光
                if (DirtyFlagCode.UsePlayerLit == (_dataIsDirty & DirtyFlagCode.UsePlayerLit))
                {
                    if (_isUsePlayerLight)
                    {
                        Shader.DisableKeyword("_USE_PLAYER_SPOTLIGHT_OFF");
                        Shader.EnableKeyword("_USE_PLAYER_SPOTLIGHT_ON");
                    }
                    else
                    {
                        Shader.DisableKeyword("_USE_PLAYER_SPOTLIGHT_ON");
                        Shader.EnableKeyword("_USE_PLAYER_SPOTLIGHT_OFF");
                    }
                }
                /*
                //法线设置
                if (DirtyFlagCode.NormalScale == (_dataIsDirty & DirtyFlagCode.NormalScale))
                {
                    Shader.SetGlobalFloat(_normalScalePropID, _normalScale);
                }*/
                _dataIsDirty = DirtyFlagCode.None;
            }
        }
        #endregion

        #region//静态方法以及变量
        //Shader属性ID
        private static int _heightFogSunColorPropID = -1;
        private static int _heightFogColorPropID = -1;
        private static int _heightFogInfoPropID = -1;
        private static int _playerPosPropID = -1;
        private static int _normalScalePropID = -1;
        private static int _playerLightColorPropID;

        private static void BuildPropertyID()
        {
            _heightFogSunColorPropID = Shader.PropertyToID("_HeightFogSunColor");
            _heightFogColorPropID = Shader.PropertyToID("_HeightFogColor");
            _heightFogInfoPropID = Shader.PropertyToID("_HeightFogInfo");
            _playerPosPropID = Shader.PropertyToID("_PlayerPos");
            _playerLightColorPropID = Shader.PropertyToID("_PlayerLitColorAtten");
            _normalScalePropID = Shader.PropertyToID("_NormalScale");
            Debug.Log("BuildPropertyID Finished!!::"+ _heightFogSunColorPropID);
        }
        #endregion

        #region//子类
        [System.Flags]
        private enum DirtyFlagCode
        {
            None = 0,
            HeightFogSunColor = 1,
            HeightFogColor = 2,
            HeightFogInfo = 4,
            PlayerPos = 8,
            PlayerLitColor = 16,
            UsePlayerLit = 32,
            All = 63,
        }
        #endregion
    }
}