WEB-34093 JSON Schema: improve the status for not yet downloaded schemas

+ fix rewriting urls when file extension is already provided

json/src/com/jetbrains/jsonSchema/remote/JsonFileResolver.java

@@ -40,7 +40,8 @@ public class JsonFileResolver {
       return JsonSchemaCatalogManager.DEFAULT_CATALOG_HTTPS;
     }
     if (StringUtil.startsWithIgnoreCase(urlString, JsonSchemaRemoteContentProvider.STORE_URL_PREFIX_HTTP)) {
-      return StringUtil.replace(urlString, "http://json.schemastore.org/", "https://schemastore.azurewebsites.net/schemas/json/") + ".json";
+      String newUrl = StringUtil.replace(urlString, "http://json.schemastore.org/", "https://schemastore.azurewebsites.net/schemas/json/");
+      return newUrl.endsWith(".json") ? newUrl : newUrl + ".json";
     }
     return urlString;
   }

json/src/com/jetbrains/jsonSchema/widget/JsonSchemaStatusWidget.java

@@ -126,23 +126,10 @@ class JsonSchemaStatusWidget extends EditorBasedStatusBarPopup {
       //noinspection EnumSwitchStatementWhichMissesCases
       switch (info.getState()) {
         case DOWNLOADING_NOT_STARTED:
+          addDownloadingUpdateListener(info);
+          return getNoSchemaState();
         case DOWNLOADING_IN_PROGRESS:
-          info.addDownloadingListener(new FileDownloadingAdapter() {
-            @Override
-            public void fileDownloaded(VirtualFile localFile) {
-              update();
-            }
-
-            @Override
-            public void errorOccurred(@NotNull String errorMessage) {
-              update();
-            }
-
-            @Override
-            public void downloadingCancelled() {
-              update();
-            }
-          });
+          addDownloadingUpdateListener(info);
           return new MyWidgetState("Download is scheduled or in progress", "Downloading JSON schema", false);
         case ERROR_OCCURRED:
           return getDownloadErrorState(info.getErrorMessage());
@@ -171,6 +158,25 @@ class JsonSchemaStatusWidget extends EditorBasedStatusBarPopup {
                              true);
   }
 
+  private void addDownloadingUpdateListener(@NotNull RemoteFileInfo info) {
+    info.addDownloadingListener(new FileDownloadingAdapter() {
+      @Override
+      public void fileDownloaded(VirtualFile localFile) {
+        update();
+      }
+
+      @Override
+      public void errorOccurred(@NotNull String errorMessage) {
+        update();
+      }
+
+      @Override
+      public void downloadingCancelled() {
+        update();
+      }
+    });
+  }
+
   private boolean isValidSchemaFile(VirtualFile schemaFile) {
     if (schemaFile == null || !myService.isApplicableToFile(schemaFile) || !myService.isSchemaFile(schemaFile)) return false;
     FileType type = schemaFile.getFileType();