using ESRI.ArcGIS.Geodatabase;
using ESRI.ArcGIS.Geometry;
using GaussCalculateLibrary;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Kingo.RuleCheck
{
    public class RuleCommon
    {
        /// <summary>
        ///  计算图形面积
        /// </summary>
        /// <param name="geo"></param>
        /// <returns></returns>
        public static double GetArea(IGeometry geo)
        {
            try
            {
                // 1、获得投影
                string SphName = geo.SpatialReference.Name.ToString().ToUpper();
                // 2、获得椭球
                ICoordinate coordinate = CoordinateFactory.CreateCoordinate();
                if (SphName.Contains("XIAN_1980") || SphName.Contains("XIAN1980"))
                {
                    coordinate = CoordinateFactory.CreateCoordinate(GaussCalculateLibrary.Spheroid.SphXian80);
                }
                else if (SphName.Contains("BEIJING_1954") || SphName.Contains("BEIJING1954"))
                {
                    coordinate = CoordinateFactory.CreateCoordinate(GaussCalculateLibrary.Spheroid.SphBeijing54);
                }
                else if (SphName.Contains("WGS_1984") || SphName.Contains("WGS1984"))
                {
                    coordinate = CoordinateFactory.CreateCoordinate(GaussCalculateLibrary.Spheroid.SphWGS84);
                }
                else if (SphName.Contains("CGCS_2000") || SphName.Contains("CGCS2000"))
                {
                    coordinate = CoordinateFactory.CreateCoordinate(GaussCalculateLibrary.Spheroid.SphCGCS2000);
                }
                else if (geo.SpatialReference is IGeographicCoordinateSystem && (SphName.Equals("GCS_China_Geodetic_Coordinate_System_2000", StringComparison.CurrentCultureIgnoreCase) || SphName.Contains("GCS_China") || SphName.Contains("Geodetic_Coordinate_System_2000")))
                {
                    coordinate = CoordinateFactory.CreateCoordinate(GaussCalculateLibrary.Spheroid.SphCGCS2000Geo);
                }
                else
                {
                    return -1;
                }
                // 3、计算面积

                double PolygonArea = 0.0;
                // 4、保留两位小数
                PolygonArea = Math.Round(coordinate.CalculateTerranArea(geo), 2, MidpointRounding.AwayFromZero);
                return PolygonArea;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

        /// <summary>
        /// 查询相交总面积
        /// </summary>
        /// <param name="geo"></param>
        /// <param name="featureClass"></param>
        /// <param name="whereClause"></param>
        /// <param name="geoWKID"></param>
        /// <returns></returns>
        public static double GetIntersectArea(IGeometry geo, IFeatureClass featureClass, string whereClause, int geoWKID)
        {
            IGeoDataset pGeoDataset = (IGeoDataset)featureClass;
            ISpatialReference pSpatialReference = pGeoDataset.SpatialReference;
            if (pSpatialReference.FactoryCode != geoWKID && (geo.SpatialReference == null || geo.SpatialReference.FactoryCode != pSpatialReference.FactoryCode))
            {
                geo.Project(pSpatialReference);
            }
            ISpatialFilter spatialFilter = new SpatialFilterClass()
            {
                Geometry = geo,
                WhereClause = whereClause
            };
            IFeatureCursor featureCursor = featureClass.Search(spatialFilter, true);
            IFeature feature = featureCursor.NextFeature();
            double intersectMJ = 0;
            while (feature != null)
            {

                feature = featureCursor.NextFeature();
                IGeometry geoIntersect = CheckHelper.CommonHelper.InterSect(geo, feature.ShapeCopy);
                if (geoIntersect != null)
                {
                    intersectMJ += GetArea(geoIntersect);
                }
            }
            return intersectMJ;
        }

        /// <summary>
        /// 获取线状地物宽度
        /// </summary>
        /// <param name="geo"></param>
        /// <returns></returns>
        public static double GetGeometryWidth(IGeometry geo)
        {
            IArea iarea = geo as IArea;
            if (iarea == null)
            {
                return 0;
            }
            double area = Math.Abs(iarea.Area);
            if (area <= 0)
            {
                return 0;
            }
            ITopologicalOperator2 topo2 = geo as ITopologicalOperator2;
            IPolyline line = topo2.Boundary as IPolyline;
            if (line == null)
            {
                return 0;
            }
            double length = line.Length;
            if (length <= 0 || length.Equals(double.NaN))
            {
                return 0;
            }
            try
            {
                //按照一元二次方程求解宽度
                //长=X,宽=Y,周长=C，面积=S
                //（X+Y）*2=C
                //  X*Y = S
                //由上计算出：Y^2-(C/2)Y+S=0;
                //二元一次方程求解常量
                double a = 1;
                double b = -(length / 2);//-(C/2)
                double c = area;//S
                double d = b * b - 4 * a * c;
                double Y = Math.Round(area / (length / 2), 1, MidpointRounding.AwayFromZero);
                if (d > 0)
                {
                    double x1 = ((-b) - Math.Sqrt(d)) / 2;
                    double x2 = ((-b) + Math.Sqrt(d)) / 2;
                    if (x1 > 0 && Math.Abs(x1 - Y) < Math.Abs(x2 - Y))
                    {
                        Y = Math.Round(x1, 1, MidpointRounding.AwayFromZero);
                    }
                    else if (x2 > 0 && Math.Abs(x2 - Y) < Math.Abs(x1 - Y))
                    {
                        Y = Math.Round(x2, 1, MidpointRounding.AwayFromZero);
                    }
                }
                else
                {
                    Y = Math.Round(area / (length / 2), 1, MidpointRounding.AwayFromZero);
                }
                return Y;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
    }
}