DbGeography polygon to JSON

Question

I store DbGeography polygon in database. My controller gets polygons from database and I need to convert them to JSON.

    var polygons = db.Areas
    .Where(x => x.Type == type)
    .Select(x => new ViewArea
    {
       Id = x.Id,
       Type = x.Type,
       Rate = x.Rate,
       Polygon = x.Polygon,
    });
    return Json(polygons, JsonRequestBehavior.AllowGet);

I try to use getJSON to take polygons from server, but can't convert DbGeography to JSON. How to make, that conversion?

Answer 1

First off, you probably don't want just any old JSON because there is a standard, GeoJSON.

You can use a NewtonSoft JsonConverter attribute like the following on your DbGeography:

  public class Foo
  {
      [JsonConverter(typeof(DbGeographyGeoJsonConverter))]
      public DbGeography Polygon { get; set; }
  }

You can convert an instance of Foo to JSON like:

var foo = new Foo { Polygon = DbGeography.FromText(
                          "Polygon((22.3 77.4, 22.5 77.5, 22.7 77.5, 22.3 77.4))") };
var jsonText = JsonConvert.SerializeObject(foo);

This should give you something like:

{"Polygon":{"type":"Polygon","coordinates":[[[22.3,77.4],[22.5,77.5],[22.7,77.5],[22.3,77.4]]]}}

Now, the DbGeographyGeoJsonConverter class is a bit complicated and the one I provided below isn't really complete (here is a more complete version). It is good enough to consume any JSON it produces. Part of the complication comes from it being partially copy-pasted from other classes I have used to deal with geospatial well-known binary and well-known text.

using System;
using System.Collections.Generic;
using System.Data.Entity.Spatial;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;

using AplPed.Common;

using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

/// <summary>
/// The <see cref="DbGeography"/> GeoJSON converter
/// </summary>
public class DbGeographyGeoJsonConverter : JsonConverter
{
    /// <summary>
    /// Well-known-binary point value.
    /// </summary>
    private const int PointWkb = 1;

    /// <summary>
    /// Well-known-binary line value.
    /// </summary>
    private const int LineStringWkb = 2;

    /// <summary>
    /// Well-known-binary polygon value.
    /// </summary>
    private const int PolygonWkb = 3;

    /// <summary>
    /// Well-known-binary multi-point value.
    /// </summary>
    private const int MultiPointWkb = 4;

    /// <summary>
    /// Well-known-binary multi-line value.
    /// </summary>
    private const int MultiLineStringWkb = 5;

    /// <summary>
    /// Well-known-binary multi-polygon value.
    /// </summary>
    private const int MultiPolygonWkb = 6;

    /// <summary>
    /// Well-known-binary geometry collection value.
    /// </summary>
    private const int GeometryCollectionWkb = 7;

    /// <summary>
    /// Well-known-binary line value.
    /// </summary>
    private static readonly Dictionary<int, string> WkbTypes = 
    new Dictionary<int, string>
    {
        { PointWkb, "Point" },
        { LineStringWkb, "LineString" },
        { PolygonWkb, "Polygon" },
        { MultiPointWkb, "MultiPoint" },
        { MultiLineStringWkb, "MultiLineString" },
        { MultiPolygonWkb, "MultiPolygon" },
        { GeometryCollectionWkb, "GeometryCollection" }
    };

    /// <summary>
    /// The types derived from <see cref="GeoBase"/> accessed by name.
    /// </summary>
    private static readonly Dictionary<string, Type> GeoBases =
    new Dictionary<string, Type>
    {
        { "Point", typeof(Point) },
        { "LineString", typeof(LineString) },
        { "Polygon", typeof(Polygon) },
        { "MultiPoint", typeof(MultiPoint) },
        { "MultiLineString", typeof(MultiLineString) },
        { "MultiPolygon", typeof(MultiPolygon) },
        { "GeometryCollection", typeof(Collection) },
    };

    /// <summary>
    /// Read the GeoJSON type value.
    /// </summary>
    /// <param name="jsonObject">
    /// The JSON object.
    /// </param>
    /// <param name="coordinateSystem">
    /// The coordinate System.
    /// </param>
    /// <returns>
    /// A function that can read the value.
    /// </returns>
    /// <exception cref="ArgumentException">
    /// Unexpected JSON.
    /// </exception>
    /// <remarks>
    /// Leaves the reader positioned where the value should start.
    /// </remarks>
    public static GeoBase ParseJsonObjectToGeoBase(JObject jsonObject, out int? coordinateSystem)
    {
        var type = jsonObject["type"];
        if (type == null)
        {
            throw new ArgumentException(string.Format("Expected a \"type\" property, found [{0}]", string.Join(", ", jsonObject.Properties().Select(p => p.Name))));
        }

        if (type.Type != JTokenType.String)
        {
            throw new ArgumentException(string.Format("Expected a string token for the type of the GeoJSON type, got {0}", type.Type), "jsonObject");
        }

        Type geoType;
        if (!GeoBases.TryGetValue(type.Value<string>(), out geoType))
        {
            throw new ArgumentException(
            string.Format(
            "Got unsupported GeoJSON object type {0}. Expected one of [{1}]",
            type.Value<string>(),
            string.Join(", ", GeoBases.Keys)),
            "jsonObject");
        }

        var geoObject = geoType == typeof(Collection) ? jsonObject["geometries"] : jsonObject["coordinates"];
        if (geoObject == null)
        {
            throw new ArgumentException(
            string.Format(
            "Expected a field named \"{0}\", found [{1}]",
            geoType == typeof(Collection) ? "geometries" : "coordinates",
            string.Join(", ", jsonObject.Properties().Select(p => p.Name))),
            "jsonObject");
        }

        var crs = jsonObject["crs"];
        coordinateSystem = crs != null ? ParseCrs(crs.Value<JObject>()) : null;

        var geo = (GeoBase)Activator.CreateInstance(geoType);
        geo.ParseJson(geoObject.Value<JArray>());
        return geo;
    }

    /// <inheritdoc/>
    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        BinaryReader lebr;
        BinaryReader bebr;
        var geographyValue = value as DbGeography;
        int coordinateSystemId;
        if (geographyValue != null)
        {
            var br = new BinaryReader(new MemoryStream(geographyValue.AsBinary()));
            lebr = BitConverter.IsLittleEndian ? br : new ReverseEndianBinaryReader(br.BaseStream);
            bebr = BitConverter.IsLittleEndian ? new ReverseEndianBinaryReader(br.BaseStream) : br;
            coordinateSystemId = geographyValue.CoordinateSystemId;
        }
        else
        {
            var geometryValue = value as DbGeometry;
            if (geometryValue != null)
            {
                var br = new BinaryReader(new MemoryStream(geometryValue.AsBinary()));
                lebr = BitConverter.IsLittleEndian ? br : new ReverseEndianBinaryReader(br.BaseStream);
                bebr = BitConverter.IsLittleEndian ? new ReverseEndianBinaryReader(br.BaseStream) : br;
                coordinateSystemId = geometryValue.CoordinateSystemId;
            }
            else
            {
                throw new ArgumentException(
                string.Format("Expecting DbGeography or DbGeometry, got {0}", value.GetType().CSharpName()), "value");
            }
        }

        var jsonObject = WriteObject(lebr, bebr);
        jsonObject.Add(
        "crs",
        new JObject
        {
            new JProperty("type", "name"),
            new JProperty(
            "properties",
            new JObject { new JProperty("name", string.Format("EPSG:{0}", coordinateSystemId)) })
        });
        writer.WriteRawValue(jsonObject.ToString(Formatting.None));
    }

    /// <inheritdoc/>
    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        // Load JObject from stream
        JObject jsonObject = JObject.Load(reader);

        // Create target object based on JObject
        object target = CreateDbGeo(jsonObject, objectType);

        // Populate the object properties
        serializer.Populate(jsonObject.CreateReader(), target);

        return target;
    }

    /// <inheritdoc/>
    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(DbGeography) || objectType == typeof(DbGeometry);
    }

    /// <summary>
    /// Parse the coordinate system object and return it's value.
    /// </summary>
    /// <param name="jsonObject">
    /// The JSON object.
    /// </param>
    /// <returns>
    /// The coordinate system value; null if couldn't parse it (only a couple EPSG-style values).
    /// </returns>
    private static int? ParseCrs(JObject jsonObject)
    {
        var properties = jsonObject["properties"];
        if (properties != null && properties.Type == JTokenType.Object)
        {
            var p = properties.Value<JObject>();
            var name = p["name"];
            if (name != null)
            {
                var s = name.Value<string>();
                if (!string.IsNullOrWhiteSpace(s))
                {
                    var m = Regex.Match(
                    s,
                    @"^\s*(urn\s*:\s*ogc\s*:\s*def\s*:crs\s*:EPSG\s*:\s*[\d.]*\s*:|EPSG\s*:)\s*(?<value>\d+)\s*$",
                    RegexOptions.ExplicitCapture | RegexOptions.IgnoreCase);
                    if (m.Success)
                    {
                        return int.Parse(m.Groups["value"].Value);
                    }
                }
            }
        }

        return null;
    }

    /// <summary>
    /// Get well known binary from a <see cref="JsonReader"/>.
    /// </summary>
    /// <param name="jsonObject">
    /// The JSON object.
    /// </param>
    /// <param name="defaultCoordinateSystemId">
    /// The default coordinate system id.
    /// </param>
    /// <returns>
    /// A tuple of the well-known-binary and the coordinate system identifier.
    /// </returns>
    /// <exception cref="ArgumentException">
    /// Unexpected JSON.
    /// </exception>
    private static Tuple<byte[], int> GetWellKnownBinary(JObject jsonObject, int defaultCoordinateSystemId)
    {
        var ob = new MemoryStream();

        int? coordinateSystemId;
        var geoBase = ParseJsonObjectToGeoBase(jsonObject, out coordinateSystemId);
        geoBase.WellKnownBinary(ob);

        return new Tuple<byte[], int>(ob.ToArray(), coordinateSystemId.HasValue ? coordinateSystemId.Value : defaultCoordinateSystemId);
    }

    /// <summary>
    /// Write a well-known binary object to JSON.
    /// </summary>
    /// <param name="lebr">
    /// The little-endian binary reader.
    /// </param>
    /// <param name="bebr">
    /// The big-endian binary reader.
    /// </param>
    /// <exception cref="ArgumentException">
    /// Unexpected well-known binary.
    /// </exception>
    /// <returns>
    /// The <see cref="JObject"/> for the given binary data.
    /// </returns>
    private static JObject WriteObject(BinaryReader lebr, BinaryReader bebr)
    {
        var jsonObject = new JObject();
        var br = lebr.ReadByte() == 0 ? bebr : lebr;
        int gtype = br.ReadInt32();
        string objTypeName;
        if (!WkbTypes.TryGetValue(gtype, out objTypeName))
        {
            throw new ArgumentException(
            string.Format(
            "Unsupported type {0}. Supported types: {1}",
            gtype,
            string.Join(", ", WkbTypes.Select(kv => string.Format("({0}, {1}", kv.Key, kv.Value)))));
        }

        jsonObject.Add("type", objTypeName);

        if (gtype == GeometryCollectionWkb)
        {
            var array = new JArray();
            int count = br.ReadInt32();
            for (int i = 0; i < count; ++i)
            {
                array.Add(WriteObject(lebr, bebr));
            }

            jsonObject.Add("geometries", array);
        }
        else
        {
            var array = new JArray();
            switch (gtype)
            {
            case PointWkb:
                array.Add(br.ReadDouble());
                array.Add(br.ReadDouble());
                break;
            case LineStringWkb:
                foreach (var a in WriteLine(br))
                {
                    array.Add(a);
                }

                break;
            case PolygonWkb:
                foreach (var a in WritePolygon(br))
                {
                    array.Add(a);
                }

                break;
            case MultiPointWkb:
                int pointCount = br.ReadInt32();
                for (int i = 0; i < pointCount; ++i)
                {
                    br = lebr.ReadByte() == 0 ? bebr : lebr;
                    gtype = br.ReadInt32();
                    if (gtype != PointWkb)
                    {
                        throw new ArgumentException(
                        string.Format("Expected a type of 1, got {0}", gtype),
                        "lebr");
                    }

                    array.Add(new JArray { br.ReadDouble(), br.ReadDouble() });
                }

                break;
            case MultiLineStringWkb:
                int lineCount = br.ReadInt32();
                for (int i = 0; i < lineCount; ++i)
                {
                    br = lebr.ReadByte() == 0 ? bebr : lebr;
                    gtype = br.ReadInt32();
                    if (gtype != LineStringWkb)
                    {
                        throw new ArgumentException(
                        string.Format("Expected a type of 2, got {0}", gtype),
                        "lebr");
                    }

                    var lineArray = new JArray();
                    foreach (var a in WriteLine(br))
                    {
                        lineArray.Add(a);
                    }

                    array.Add(lineArray);
                }

                break;
            case MultiPolygonWkb:
                int polygonCount = br.ReadInt32();
                for (int i = 0; i < polygonCount; ++i)
                {
                    br = lebr.ReadByte() == 0 ? bebr : lebr;
                    gtype = br.ReadInt32();
                    if (gtype != PolygonWkb)
                    {
                        throw new ArgumentException(
                        string.Format("Expected a type of 3, got {0}", gtype),
                        "lebr");
                    }

                    var polygonArray = new JArray();
                    foreach (var a in WritePolygon(br))
                    {
                        polygonArray.Add(a);
                    }

                    array.Add(polygonArray);
                }

                break;
            default:
                throw new ArgumentException(string.Format("Unsupported geo-type {0}", gtype), "lebr");
            }

            jsonObject.Add("coordinates", array);
        }

        return jsonObject;
    }

    /// <summary>
    /// Write a JSON polygon from well-known binary.
    /// </summary>
    /// <param name="br">
    /// Read from this.
    /// </param>
    /// <returns>
    /// The <see cref="JArray"/> enumerable for the polygon.
    /// </returns>
    private static IEnumerable<JArray> WritePolygon(BinaryReader br)
    {
        var ret = new List<JArray>();
        int ringCount = br.ReadInt32();
        for (int ri = 0; ri < ringCount; ++ri)
        {
            var array = new JArray();
            foreach (var a in WriteLine(br))
            {
                array.Add(a);
            }

            ret.Add(array);
        }

        return ret;
    }

    /// <summary>
    /// Write a JSON line from well-known binary.
    /// </summary>
    /// <param name="br">
    /// Read from this.
    /// </param>
    /// <returns>
    /// The <see cref="JArray"/> enumerable for the line.
    /// </returns>
    private static IEnumerable<JArray> WriteLine(BinaryReader br)
    {
        var ret = new List<JArray>();
        int count = br.ReadInt32() * 2;
        for (int i = 0; i < count; i += 2)
        {
            var array = new JArray { br.ReadDouble(), br.ReadDouble() };
            ret.Add(array);
        }

        return ret;
    }

    /// <summary>
    /// Create a <see cref="DbGeography"/> or <see cref="DbGeometry"/> from <paramref name="jsonObject"/>.
    /// </summary>
    /// <param name="jsonObject">
    /// The JSON object.
    /// </param>
    /// <param name="objectType">
    /// The object type.
    /// </param>
    /// <returns>
    /// The <see cref="DbGeography"/> or <see cref="DbGeometry"/> 
    /// </returns>
    /// <exception cref="ArgumentException">
    /// <paramref name="objectType"/> is not a <see cref="DbGeography"/> or <see cref="DbGeometry"/>.
    /// </exception>
    private static object CreateDbGeo(JObject jsonObject, Type objectType)
    {
        Func<Tuple<byte[], int>, object> returnValue;
        int defaultCoordinateSystemId;
        if (typeof(DbGeography).IsAssignableFrom(objectType))
        {
            returnValue = x => (object)DbGeography.FromBinary(x.Item1, x.Item2);
            defaultCoordinateSystemId = DbGeography.DefaultCoordinateSystemId;
        }
        else if (typeof(DbGeometry).IsAssignableFrom(objectType))
        {
            returnValue = x => (object)DbGeometry.FromBinary(x.Item1, x.Item2);
            defaultCoordinateSystemId = DbGeometry.DefaultCoordinateSystemId;
        }
        else
        {
            throw new ArgumentException(string.Format("Expected a DbGeography or DbGeometry objectType. Got {0}", objectType.CSharpName()), "objectType");
        }

        return jsonObject.Type == JTokenType.Null || jsonObject.Type == JTokenType.None ? null : returnValue(GetWellKnownBinary(jsonObject, defaultCoordinateSystemId));
    }

    /// <summary>
    /// A <see cref="BinaryReader"/> that expects byte-reversed numeric values.
    /// </summary>
    public class ReverseEndianBinaryReader : BinaryReader
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="ReverseEndianBinaryReader"/> class.
        /// </summary>
        /// <param name="stream">
        /// The stream.
        /// </param>
        public ReverseEndianBinaryReader(Stream stream)
        : base(stream)
        {
        }

        /// <inheritdoc/>
        public override short ReadInt16()
        {
            return BitConverter.ToInt16(this.ReadBytes(2).Reverse().ToArray(), 0);
        }

        /// <inheritdoc/>
        public override int ReadInt32()
        {
            return BitConverter.ToInt32(this.ReadBytes(4).Reverse().ToArray(), 0);
        }

        /// <inheritdoc/>
        public override long ReadInt64()
        {
            return BitConverter.ToInt64(this.ReadBytes(8).Reverse().ToArray(), 0);
        }

        /// <inheritdoc/>
        public override ushort ReadUInt16()
        {
            return BitConverter.ToUInt16(this.ReadBytes(2).Reverse().ToArray(), 0);
        }

        /// <inheritdoc/>
        public override uint ReadUInt32()
        {
            return BitConverter.ToUInt32(this.ReadBytes(4).Reverse().ToArray(), 0);
        }

        /// <inheritdoc/>
        public override ulong ReadUInt64()
        {
            return BitConverter.ToUInt64(this.ReadBytes(8).Reverse().ToArray(), 0);
        }

        /// <inheritdoc/>
        public override float ReadSingle()
        {
            return BitConverter.ToSingle(this.ReadBytes(4).Reverse().ToArray(), 0);
        }

        /// <inheritdoc/>
        public override double ReadDouble()
        {
            return BitConverter.ToDouble(this.ReadBytes(8).Reverse().ToArray(), 0);
        }
    }

    /// <summary>
    /// Base class for the types that know how to parse JSON and write well-known binary.
    /// </summary>
    public abstract class GeoBase
    {
        /// <summary>
        /// The point well-known bytes descriptor.
        /// </summary>
        protected static readonly byte[] PointWkbs = BitConverter.GetBytes(PointWkb);

        /// <summary>
        /// The line-string well-known bytes descriptor.
        /// </summary>
        protected static readonly byte[] LineStringWkbs = BitConverter.GetBytes(LineStringWkb);

        /// <summary>
        /// The polygon well-known bytes descriptor.
        /// </summary>
        protected static readonly byte[] PolygonWkbs = BitConverter.GetBytes(PolygonWkb);

        /// <summary>
        /// The multi-point well-known bytes descriptor.
        /// </summary>
        protected static readonly byte[] MultiPointWkbs = BitConverter.GetBytes(MultiPointWkb);

        /// <summary>
        /// The multi-line-string well-known bytes descriptor.
        /// </summary>
        protected static readonly byte[] MultiLineStringWkbs = BitConverter.GetBytes(MultiLineStringWkb);

        /// <summary>
        /// The multi-polygon well-known bytes descriptor.
        /// </summary>
        protected static readonly byte[] MultiPolygonWkbs = BitConverter.GetBytes(MultiPolygonWkb);

        /// <summary>
        /// The collection well-known bytes descriptor.
        /// </summary>
        protected static readonly byte[] GeometryCollectionWkbs = BitConverter.GetBytes(GeometryCollectionWkb);

        /// <summary>
        /// Helper function to parse a <see cref="List{T}"/> of <see cref="Position"/>.
        /// </summary>
        /// <param name="array">
        /// Get JSON from this.
        /// </param>
        /// <returns>
        /// The parsed JSON.
        /// </returns>
        /// <exception cref="ArgumentException">
        /// Unexpected JSON.
        /// </exception>
        public static List<Position> ParseListPosition(JArray array)
        {
            if (array.Cast<JArray>().Any(l => l.Count < 2))
            {
                throw new ArgumentException(
                string.Format(
                "Expected all points to have greater than two points, got {0} with zero and {1} with one",
                array.Cast<JArray>().Count(l => l.Count == 0),
                array.Cast<JArray>().Count(l => l.Count == 1)),
                "array");
            }

            return array.Select(l => new Position { P1 = (double)l[0], P2 = (double)l[1] }).ToList();
        }

        /// <summary>
        /// Helper function to parse a <see cref="List{T}"/> of <see cref="List{T}"/> of <see cref="Position"/>.
        /// </summary>
        /// <param name="array">
        /// Get JSON from this.
        /// </param>
        /// <returns>
        /// The parsed JSON.
        /// </returns>
        /// <exception cref="ArgumentException">
        /// Unexpected JSON.
        /// </exception>
        public static List<List<Position>> ParseListListPosition(JArray array)
        {
            if (array.Cast<JArray>().Any(r => r.Cast<JArray>().Any(l => l.Count < 2)))
            {
                throw new ArgumentException(
                string.Format(
                "Expected all points to have greater than two points, got {0} with zero and {1} with one",
                array.Cast<JArray>().Sum(r => r.Cast<JArray>().Count(l => l.Count == 0)),
                array.Cast<JArray>().Sum(r => r.Cast<JArray>().Count(l => l.Count == 1))),
                "array");
            }

            return array.Select(r => r.Select(l => new Position { P1 = (double)l[0], P2 = (double)l[1] }).ToList()).ToList();
        }

        /// <summary>
        /// Helper function to parse a <see cref="List{T}"/> of <see cref="List{T}"/> of <see cref="List{T}"/> of <see cref="Position"/>.
        /// </summary>
        /// <param name="array">
        /// Get JSON from this.
        /// </param>
        /// <returns>
        /// The parsed JSON.
        /// </returns>
        /// <exception cref="ArgumentException">
        /// Unexpected JSON.
        /// </exception>
        public static List<List<List<Position>>> ParseListListListPosition(JArray array)
        {
            if (array.Cast<JArray>().Any(p => p.Cast<JArray>().Any(r => r.Cast<JArray>().Any(l => l.Count < 2))))
            {
                throw new ArgumentException(
                string.Format(
                "Expected all points to have greater than two points, got {0} with zero and {1} with one",
                array.Cast<JArray>().Sum(p => p.Cast<JArray>().Sum(r => r.Cast<JArray>().Count(l => l.Count == 0))),
                array.Cast<JArray>().Sum(p => p.Cast<JArray>().Sum(r => r.Cast<JArray>().Count(l => l.Count == 1)))),
                "array");
            }

            return array.Select(p => p.Select(r => r.Select(l => new Position { P1 = (double)l[0], P2 = (double)l[1] }).ToList()).ToList()).ToList();
        }

        /// <summary>
        /// Write the contents to <paramref name="sout"/> in well-known 
        /// binary format.
        /// </summary>
        /// <param name="sout">
        /// The stream to write the position to.
        /// </param>
        public abstract void WellKnownBinary(Stream sout);

        /// <summary>
        /// Parse JSON into the <see cref="GeoBase"/>-derived type.
        /// </summary>
        /// <param name="array">
        /// Get JSON from this.
        /// </param>
        public abstract void ParseJson(JArray array);
    }

    /// <summary>
    /// The position.
    /// </summary>
    public class Position : GeoBase
    {
        /// <summary>
        /// Gets or sets the first value of the position.
        /// </summary>
        public double P1 { get; set; }

        /// <summary>
        /// Gets or sets the second value of the position.
        /// </summary>
        public double P2 { get; set; }

        /// <inheritdoc/>
        public override void WellKnownBinary(Stream sout)
        {
            sout.Write(BitConverter.GetBytes(this.P1), 0, 8);
            sout.Write(BitConverter.GetBytes(this.P2), 0, 8);
        }

        /// <inheritdoc/>
        public override void ParseJson(JArray array)
        {
            if (array.Count < 2)
            {
                throw new ArgumentException(string.Format("Expected at least 2 points for a position, got {0}", array.Count), "array");
            }

            this.P1 = (double)array[0];
            this.P2 = (double)array[1];
        }
    }

    // ReSharper disable RedundantNameQualifier

    /// <summary>
    /// The point.
    /// </summary>
    public class Point : GeoBase
    {
        /// <summary>
        /// Gets or sets the position.
        /// </summary>
        public Position Position { get; set; }

        /// <inheritdoc/>
        public override void WellKnownBinary(Stream sout)
        {
            sout.WriteByte(BitConverter.IsLittleEndian ? (byte)1 : (byte)0);
            sout.Write(GeoBase.PointWkbs, 0, 4);
            this.Position.WellKnownBinary(sout);
        }

        /// <inheritdoc/>
        public override void ParseJson(JArray array)
        {
            this.Position = new Position();
            this.Position.ParseJson(array);
        }
    }

    /// <summary>
    /// The line string.
    /// </summary>
    public class LineString : GeoBase
    {
        /// <summary>
        /// Gets or sets the points.
        /// </summary>
        public List<Point> Points { get; set; }

        /// <inheritdoc/>
        public override void WellKnownBinary(Stream sout)
        {
            sout.WriteByte(BitConverter.IsLittleEndian ? (byte)1 : (byte)0);
            sout.Write(GeoBase.LineStringWkbs, 0, 4);
            sout.Write(BitConverter.GetBytes(this.Points.Count), 0, 4);
            foreach (var point in this.Points)
            {
                point.Position.WellKnownBinary(sout);
            }
        }

        /// <inheritdoc/>
        public override void ParseJson(JArray array)
        {
            if (array.Cast<JArray>().Any(l => l.Count < 2))
            {
                throw new ArgumentException(
                string.Format(
                "Expected all points to have greater than two points, got {0} with zero and {1} with one",
                array.Cast<JArray>().Count(l => l.Count == 0),
                array.Cast<JArray>().Count(l => l.Count == 1)),
                "array");
            }

            this.Points = array.Cast<JArray>().Select(l => new Point { Position = new Position { P1 = (double)l[0], P2 = (double)l[1] } }).ToList();
        }
    }

    /// <summary>
    /// The polygon.
    /// </summary>
    public class Polygon : GeoBase
    {
        /// <summary>
        /// Gets or sets the rings.
        /// </summary>
        public List<List<Position>> Rings { get; set; }

        /// <inheritdoc/>
        public override void WellKnownBinary(Stream sout)
        {
            sout.WriteByte(BitConverter.IsLittleEndian ? (byte)1 : (byte)0);
            sout.Write(GeoBase.PolygonWkbs, 0, 4);
            sout.Write(BitConverter.GetBytes(this.Rings.Count), 0, 4);
            foreach (var ring in this.Rings)
            {
                sout.Write(BitConverter.GetBytes(ring.Count), 0, 4);
                foreach (var position in ring)
                {
                    position.WellKnownBinary(sout);
                }
            }
        }

        /// <inheritdoc/>
        public override void ParseJson(JArray array)
        {
            this.Rings = GeoBase.ParseListListPosition(array);
        }
    }

    /// <summary>
    /// The multi-point.
    /// </summary>
    public class MultiPoint : GeoBase
    {
        /// <summary>
        /// Gets or sets the points.
        /// </summary>
        public List<Position> Points { get; set; }

        /// <inheritdoc/>
        public override void WellKnownBinary(Stream sout)
        {
            byte order = BitConverter.IsLittleEndian ? (byte)1 : (byte)0;
            sout.WriteByte(order);
            sout.Write(GeoBase.MultiPointWkbs, 0, 4);
            sout.Write(BitConverter.GetBytes(this.Points.Count), 0, 4);
            foreach (var point in this.Points)
            {
                sout.WriteByte(order);
                sout.Write(GeoBase.PointWkbs, 0, 4); // Point
                point.WellKnownBinary(sout);
            }
        }

        /// <inheritdoc/>
        public override void ParseJson(JArray array)
        {
            this.Points = GeoBase.ParseListPosition(array);
        }
    }

    /// <summary>
    /// The multi-line.
    /// </summary>
    public class MultiLineString : GeoBase
    {
        /// <summary>
        /// Gets or sets the line strings.
        /// </summary>
        public List<List<Position>> LineStrings { get; set; }

        /// <inheritdoc/>
        public override void WellKnownBinary(Stream sout)
        {
            byte order = BitConverter.IsLittleEndian ? (byte)1 : (byte)0;
            sout.WriteByte(order);
            // ReSharper disable once RedundantNameQualifier
            sout.Write(GeoBase.MultiLineStringWkbs, 0, 4);
            sout.Write(BitConverter.GetBytes(this.LineStrings.Count), 0, 4);
            foreach (var lineString in this.LineStrings)
            {
                sout.WriteByte(order);
                sout.Write(GeoBase.LineStringWkbs, 0, 4);
                sout.Write(BitConverter.GetBytes(lineString.Count), 0, 4);
                foreach (var position in lineString)
                {
                    position.WellKnownBinary(sout);
                }
            }
        }

        /// <inheritdoc/>
        public override void ParseJson(JArray array)
        {
            this.LineStrings = GeoBase.ParseListListPosition(array);
        }
    }

    /// <summary>
    /// The multi-polygon.
    /// </summary>
    public class MultiPolygon : GeoBase
    {
        /// <summary>
        /// Gets or sets the polygons.
        /// </summary>
        public List<List<List<Position>>> Polygons { get; set; }

        /// <inheritdoc/>
        public override void WellKnownBinary(Stream sout)
        {
            byte order = BitConverter.IsLittleEndian ? (byte)1 : (byte)0;
            sout.WriteByte(order);
            sout.Write(GeoBase.MultiPolygonWkbs, 0, 4);
            sout.Write(BitConverter.GetBytes(this.Polygons.Count), 0, 4);
            foreach (var polygon in this.Polygons)
            {
                sout.WriteByte(order);
                sout.Write(GeoBase.PolygonWkbs, 0, 4);
                sout.Write(BitConverter.GetBytes(polygon.Count), 0, 4);
                foreach (var ring in polygon)
                {
                    sout.Write(BitConverter.GetBytes(ring.Count), 0, 4);
                    foreach (var position in ring)
                    {
                        position.WellKnownBinary(sout);
                    }
                }
            }
        }

        /// <inheritdoc/>
        public override void ParseJson(JArray array)
        {
            this.Polygons = GeoBase.ParseListListListPosition(array);
        }
    }

    /// <summary>
    /// The <see cref="GeoBase"/> collection.
    /// </summary>
    public class Collection : GeoBase
    {
        /// <summary>
        /// Gets or sets the entries.
        /// </summary>
        public List<GeoBase> Entries { get; set; }

        /// <inheritdoc/>
        public override void WellKnownBinary(Stream o)
        {
            o.WriteByte(BitConverter.IsLittleEndian ? (byte)1 : (byte)0);
            o.Write(GeoBase.GeometryCollectionWkbs, 0, 4);
            o.Write(BitConverter.GetBytes(this.Entries.Count), 0, 4);
            foreach (var entry in this.Entries)
            {
                entry.WellKnownBinary(o);
            }
        }

        /// <inheritdoc/>
        public override void ParseJson(JArray array)
        {
            this.Entries = new List<GeoBase>();
            foreach (var elem in array)
            {
                if (elem.Type != JTokenType.Object)
                {
                    throw new ArgumentException(
                    string.Format("Expected object elements of the collection array, got {0}", elem.Type),
                    "array");
                }

                int? dummyCoordinateSystem;
                this.Entries.Add(DbGeographyGeoJsonConverter.ParseJsonObjectToGeoBase((JObject)elem, out dummyCoordinateSystem));
            }
        }
    }

    // ReSharper restore RedundantNameQualifier
}