using Autodesk.Revit.DB;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace GraphicsStudy
{
    class MeshData
    {
        #region 数据

        /// <summary>
        /// 顶点集合
        /// </summary>
        public List<XYZ> VerticeList { get; set; }
        /// <summary>
        /// 面索引集合
        /// </summary>
        public List<int> IndiceList { get; set; }
        /// <summary>
        /// 顶点法向量集合
        /// </summary>
        public List<XYZ> VerticeNormalList { get; set; }
        /// <summary>
        /// 对应材质数组编号
        /// </summary>
        public int MaterialIndex { get; set; }
        #endregion

        #region 构造函数
        public MeshData()
        {
            VerticeList = new List<XYZ>();
            IndiceList = new List<int>();
            VerticeNormalList = new List<XYZ>();
        }
        #endregion

        #region 方法
        /// <summary>
        /// 把顶点信息添加到集合中，然后返回对应的点在顶点集合中的索引
        /// </summary>
        /// <param name="meshVerticeList"></param>
        /// <returns></returns>
        public List<int> AddVertice(IList<XYZ> meshVerticeList, XYZ faceNormal)
        {
            List<int> verticelIndexList = new List<int>();
            foreach (XYZ meshVertice in meshVerticeList)
            {
                int index = VerticeList.FindIndex(x => x.DistanceTo(meshVertice) < 1.ToFeet());
                if (index == -1)
                {
                    VerticeList.Add(meshVertice);
                    VerticeNormalList.Add(faceNormal);
                    verticelIndexList.Add(VerticeList.Count() - 1);
                }
                else
                {
                    verticelIndexList.Add(index);
                    //法向量相加再单位化
                    if (VerticeNormalList[index].AngleTo(faceNormal) < 91.ToRad())
                    {
                        VerticeNormalList[index] = (faceNormal + VerticeNormalList[index]).Normalize();
                    }
                }
            }
            return verticelIndexList;
        }

        public string ToJosn()
        {
            string result = null;
            result = string.Format
                (
                "\n \"vertices\":[\n{0}\n],"
                + "\n \"indices\":[\n{1}\n],"
                + "\n \"normals\":[\n{2}\n],"
                + "\n \"material\":{3}",
                string.Join(",\n", VerticeList.Select<XYZ, string>(x => XYZTransform(x,false))),
                string.Join(",\n", IndiceList.Select<int, string>(x => x.ToString())),
                string.Join(",\n", VerticeNormalList.Select<XYZ, string>(x => XYZTransform(x))),
                MaterialIndex
                );

            return "\n{" + result + "\n}";
        }

        

        private string XYZTransform(XYZ point,bool isDirection=true)
        {
            string result = null;
            if (isDirection)
            {
                point = point.Normalize();
                result = $"{point.X.Round(0)},\n{point.Y.Round(0)},\n{point.Z.Round(0)}";
            }
            else
            {
                result = $"{point.X.ToMM().Round(0)},\n{point.Y.ToMM().Round(0)},\n{point.Z.ToMM().Round(0)}";
            }
            
            return result;
        }


        #endregion
    }
}