GeoJson polygon converter

using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.IO;
using CityGen3D;
using GeoJSON.Net;
using GeoJSON.Net.Feature;
using GeoJSON.Net.Geometry;
using Newtonsoft.Json;
using UnityEditor;
using UnityEngine;
using Feature = GeoJSON.Net.Feature.Feature;

// ReSharper disable InvertIf

public class TestGeoJson : MonoBehaviour
{
    public string jsonFilename = "test.geojson";

    public static void ProcessGeoJson (string path)
    {
        string json = File.ReadAllText (path);
        FeatureCollection jsonObject = JsonConvert.DeserializeObject<FeatureCollection> (json);

        GeoCoord origin = Map.Instance.data.GetOrigin ();
        List<Vector3> buildingPoints = new List<Vector3> ();
        foreach (Feature feature in jsonObject.Features)
        {
            buildingPoints.Clear ();
            string buildingId = string.Empty;
            if (feature.Properties.TryGetValue ("uuid", out object buildingIdProperty))
            {
                buildingId = (string) buildingIdProperty;
            }
            IGeometryObject geometry = feature.Geometry;
            if (geometry.Type == GeoJSONObjectType.Polygon)
            {
                Polygon polygon = (Polygon) geometry;
                ReadOnlyCollection<LineString> coordinates = polygon.Coordinates;
                if (coordinates != null && coordinates.Count != 0)
                {
                    foreach (LineString coordinate in coordinates)
                    {
                        ReadOnlyCollection<IPosition> points = coordinate.Coordinates;
                        if (points != null && points.Count != 0)
                        {
                            foreach (IPosition point in points)
                            {
                                double latitude = point.Latitude;
                                double longitude = point.Longitude;
                                GeoCoord geoPos = new GeoCoord (latitude, longitude);
                                MapCoord mapPos = geoPos.GetMapCoord (origin);
                                buildingPoints.Add (mapPos.GetPosition ());
                            }
                        }
                    }

                    GameObject building = Map.Instance.mapBuildings.Create (0, buildingPoints);
                    if (!string.IsNullOrEmpty (buildingId))
                    {
                        building.name += " " + buildingId;
                    }
                    if (building != null)
                    {
                        building.GetComponent<MapBuilding> ().RefreshPivot ();
                        building.GetComponent<MapBuilding> ().BuildMap ();
                    }
                }
            }
        }
    }
}

[CustomEditor (typeof (TestGeoJson))]
public class EditorCreateBuilding : Editor
{
    public override void OnInspectorGUI ()
    {
        DrawDefaultInspector ();
        EditorGUILayout.Separator ();
        TestGeoJson script = (TestGeoJson) target;
        if (GUILayout.Button ("Process GeoJson File"))
        {
            string path = Path.Combine (Application.dataPath, "Data", script.jsonFilename);
            TestGeoJson.ProcessGeoJson (path);
        }
    }
}