From 45b5d037bb569a732ced7b6ddb429bea682758ab Mon Sep 17 00:00:00 2001
From: Clemens <fischer.clemens@gmail.com>
Date: Sat, 22 Jan 2022 20:32:17 +0100
Subject: [PATCH] Updated GeoApiProjectionFactory

---
 MapControl/Shared/MapProjectionFactory.cs     |  5 ++-
 .../Shared/GeoApiProjectionFactory.cs         | 40 +++----------------
 MapUiTools/Shared/MapProjectionsMenuButton.cs |  4 +-
 3 files changed, 11 insertions(+), 38 deletions(-)

diff --git a/MapControl/Shared/MapProjectionFactory.cs b/MapControl/Shared/MapProjectionFactory.cs
index a312e719..e4f292a0 100644
--- a/MapControl/Shared/MapProjectionFactory.cs
+++ b/MapControl/Shared/MapProjectionFactory.cs
@@ -6,7 +6,7 @@ namespace MapControl
 {
     public class MapProjectionFactory
     {
-        public virtual MapProjection CreateProjection(string crsId)
+        public virtual MapProjection GetProjection(string crsId)
         {
             MapProjection projection = null;
 
@@ -43,6 +43,9 @@ namespace MapControl
                 case "EPSG:97003": // proprietary CRS ID
                     projection = new AzimuthalEquidistantProjection { CrsId = crsId };
                     break;
+
+                default:
+                    break;
             }
 
             return projection;
diff --git a/MapProjections/Shared/GeoApiProjectionFactory.cs b/MapProjections/Shared/GeoApiProjectionFactory.cs
index d419a45f..efdbdfa2 100644
--- a/MapProjections/Shared/GeoApiProjectionFactory.cs
+++ b/MapProjections/Shared/GeoApiProjectionFactory.cs
@@ -2,11 +2,6 @@
 // © 2022 Clemens Fischer
 // Licensed under the Microsoft Public License (Ms-PL)
 
-using System;
-using System.Collections.Generic;
-using System.Diagnostics;
-using System.Net.Http;
-
 namespace MapControl.Projections
 {
     public class GeoApiProjectionFactory : MapProjectionFactory
@@ -22,10 +17,7 @@ namespace MapControl.Projections
         public const int Wgs84UtmSouthLast = 32760;
         public const int Wgs84UpsSouth = 32761;
 
-        private readonly Dictionary<int, string> wkts = new Dictionary<int, string>();
-        private readonly HttpClient httpClient = new HttpClient();
-
-        public override MapProjection CreateProjection(string crsId)
+        public override MapProjection GetProjection(string crsId)
         {
             MapProjection projection = null;
 
@@ -62,17 +54,16 @@ namespace MapControl.Projections
                         break;
 
                     default:
-                        projection = new GeoApiProjection(GetWkt(epsgCode));
                         break;
                 }
             }
 
-            return projection ?? base.CreateProjection(crsId);
+            return projection ?? base.GetProjection(crsId);
         }
 
         private static string GetEtrs89UtmWkt(int epsgCode)
         {
-            const string etrs89UtmWktFormat
+            const string wktFormat
                 = "PROJCS[\"ETRS89 / UTM zone {1}N\","
                 + "GEOGCS[\"ETRS89\","
                 + "DATUM[\"European_Terrestrial_Reference_System_1989\","
@@ -97,29 +88,10 @@ namespace MapControl.Projections
                 + "AXIS[\"Northing\",NORTH],"
                 + "AUTHORITY[\"EPSG\",\"{0}\"]]";
 
-            int centralMeridian = 6 * (epsgCode - Etrs89UtmNorthFirst) - 15;
+            var zone = epsgCode % 100;
+            var centralMeridian = 6 * (epsgCode - Etrs89UtmNorthFirst) - 15;
 
-            return string.Format(etrs89UtmWktFormat, epsgCode, epsgCode - 25800, centralMeridian);
-        }
-
-        private string GetWkt(int epsgCode)
-        {
-            if (!wkts.TryGetValue(epsgCode, out string wkt))
-            {
-                var url = string.Format("https://epsg.io/{0}.wkt", epsgCode);
-
-                try
-                {
-                    wkt = httpClient.GetStringAsync(url).Result; // potential deadlock?
-                    wkts[epsgCode] = wkt;
-                }
-                catch (Exception ex)
-                {
-                    Debug.WriteLine($"GeoApiProjectionFactory.GetWkt({epsgCode}): {url}: {ex.Message}");
-                }
-            }
-
-            return wkt;
+            return string.Format(wktFormat, epsgCode, zone, centralMeridian);
         }
     }
 }
diff --git a/MapUiTools/Shared/MapProjectionsMenuButton.cs b/MapUiTools/Shared/MapProjectionsMenuButton.cs
index f506c907..9dddb870 100644
--- a/MapUiTools/Shared/MapProjectionsMenuButton.cs
+++ b/MapUiTools/Shared/MapProjectionsMenuButton.cs
@@ -4,7 +4,6 @@
 
 using System.Collections.ObjectModel;
 using System.Collections.Specialized;
-using System.Diagnostics;
 using System.Linq;
 #if WINUI
 using Microsoft.UI.Xaml;
@@ -14,7 +13,6 @@ using Windows.UI.Xaml;
 using Windows.UI.Xaml.Markup;
 #else
 using System.Windows;
-using System.Windows.Controls;
 using System.Windows.Markup;
 #endif
 
@@ -91,7 +89,7 @@ namespace MapControl.UiTools
             if (selectedProjection != projection)
             {
                 selectedProjection = projection;
-                Map.MapProjection = MapProjection.Factory.CreateProjection(selectedProjection);
+                Map.MapProjection = MapProjection.Factory.GetProjection(selectedProjection);
             }
 
             UpdateCheckedStates();