Check if all same projects.

src/main/resources/eu/simstadt/regionchooser/website/script/simstadt_openlayers.js

@@ -222,8 +222,18 @@ var regionChooser = (function(){
 			return kml_source.getFeatureById(i);
 		})
 		
-		var project = features[0].get("project"); //TODO: Check all the same
-		var srsName = features[0].get("srsName"); //TODO: Check all the same
+		var project = features[0].get("project");
+		var srsName = features[0].get("srsName");
+		
+		if (!features.every( f => f.get("project") === project)){
+			dataPanel.append("<h2 class='error'>Sorry, the CityGML files should all belong to the same project.</h2><br/>\n");
+			return;
+		}
+		
+		if (!features.every( f => f.get("srsName") === srsName)){
+			dataPanel.append("<h2 class='error'>Sorry, the CityGML files should all be written with the same coordinate system.</h2><br/>\n");
+		}
+		
 		var citygmlNames = features.map(f => f.get("name"));
 		// Waiting 100ms in order to let the cursor change
 		setTimeout(function() {