using UnityEngine;
using System.Collections.Generic;

namespace Thousandto.Launcher.ExternalLibs
{
    public class GrassRelationScript : MonoBehaviour
    {
        #region//私有变量
        [SerializeField]
        private ChildMeshDataScript[] _relationScripts = null;
        //[SerializeField]
        private Vector3[] _newVertices = null;
        [SerializeField]
        private Mesh _newMesh = null;

        //组合的mesh的位置
        [SerializeField]
        private Vector3 _meshPostion = Vector3.zero;
        //看到草的距离 --- 太远的就不处理了.
        private const float CN_VIEW_LENGTH = 25f;
        
        //当前摄像机
        private Camera _current = null;
        //当前摄像机的Transform
        private Transform _cameraTrans = null;
        //当前是否可以被泵装
        private bool _beCanCollision = false;
        #endregion

        #region//static
        //当前需不需要处理顶点动画
        public  static bool IsEnabled = false;
        #endregion

        #region//属性
        private Transform TransformInst
        {
            get
            {
                return transform;
            }
        }

        public Vector3[] NewVertices
        {
            get
            {
                return _newVertices;
            }

            set
            {
                _newVertices = value;
            }
        }
        #endregion

        #region//运行时调用
        void OnBecameInvisible()
        {
            if (IsEnabled)
            {
                SetVisible(false);
            }
            enabled = false;
        }

        void OnBecameVisible()
        {
            if (IsEnabled)
            {
                SetVisible(true);
            }
            enabled = true;
        }

        void OnWillRenderObject()
        {
            if (IsEnabled)
            {
                if (_current != Camera.current)
                {
                    _current = Camera.current;
                    _cameraTrans = Camera.current.transform;
                }
            }
        }
        private void Start()
        {
            SetVisible(IsEnabled);
            if (NewVertices == null)
            {
                NewVertices = _newMesh.vertices;
            }
        }

        //设置是否Enabled
        public static void SetEnabled(bool isEnabled)
        {
            IsEnabled = isEnabled;
        }

        //设置可见性
        public void SetVisible(bool isVisible)
        {
            for (int i = 0; i < _relationScripts.Length; i++)
            {
                _relationScripts[i].enabled = isVisible;
            }
        }

        //设置是否可以被碰撞
        private void SetBeCanCollision(bool beCanCollision)
        {
            if (beCanCollision != _beCanCollision)
            {
                _beCanCollision = beCanCollision;
                SetVisible(_beCanCollision);
            }
        }

        //更新顶点
        private void UpdateVerteices(RuntimeChildMesh info)
        {
            for (int i = 0; i < info.NewVertices.Length; i++)
            {
                NewVertices[info.StartIndex + i] = info.NewVertices[i];
            }
        }
        // Update is called once per frame
        void Update()
        {
            if (IsEnabled)
            {
                //设置
                if (_cameraTrans == null)
                {
                    SetBeCanCollision(false);
                }
                else
                {
                    SetBeCanCollision(Vector3.Distance(_cameraTrans.position, _meshPostion) < CN_VIEW_LENGTH);
                }

                if (_beCanCollision)
                {
                    bool isDirty = false;
                    for (int i = 0; _relationScripts != null && i < _relationScripts.Length; i++)
                    {
                        if (_relationScripts[i].ChildMeshInfo.IsDirty)
                        {
                            isDirty = true;
                            UpdateVerteices(_relationScripts[i].ChildMeshInfo);
                        }

                    }
                    if (isDirty)
                    {
                        _newMesh.vertices = NewVertices;
                    }
                }
            }
        }

        private void OnDestroy()
        {
            _beCanCollision = false;
            IsEnabled = false;
            _newMesh = null;
        }
        #endregion

        #region//编辑器编辑时调用
#if UNITY_EDITOR && !FUNCELL_LAUNCHER
        public void AddRelationScript(List<ChildMeshDataScript> list)
        {
            _relationScripts = list.ToArray();
        }

        public void InitCombineInfo()
        {
            for (int i = 0; i < _relationScripts.Length; i++)
            {
                var tran = _relationScripts[i].transform;
                if (i == 0)
                {
                    _meshPostion = tran.position;
                }
                else
                {
                    _meshPostion = Vector3.Slerp(_meshPostion, tran.position, 0.5f);
                }
                var child = _relationScripts[i];
                //增加小草的脚本
                var grass = Thousandto.Core.Base.UnityUtils.RequireComponent<GrassAnimateScript>(child.gameObject);
                grass.SetRunTimeScript(child);
            }
            MeshFilter mf = TransformInst.GetComponent<MeshFilter>();
            if (mf != null)
                _newMesh = mf.sharedMesh;
            //GameCenter.GameSetting.IsEnabled(GameSettingKeyCode.EnableGrass);
        }
#endif
#endregion
    }
}