Allow updating the parent project from the WebUI

This change adds support for updating the parent project of a child
project from the WebUI. This functionality is offered in the
ProjectAccessScreen. When the access rights are changed the user is
also able to change the parent project (if the user has the needed
privileges, means if he is administrator). When the user saves the
new settings only one RPC to the server is done that updates both the
access rights and the parent project property. Technically both
updates are modifications of the 'project.config' file in the
'refs/meta/config' branch. There will be only one commit for this
file that does both updates.

In the UI only valid parent projects are suggested as new parent
project (all projects that would cause a cycle in the line of parent
projects are not suggested).

Bug: issue 1298
Change-Id: Ic63bdb039ea5057a0551138f8fef9ede280b2be3
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>

gerrit-gwtui/src/main/java/com/google/gerrit/client/ui/ParentProjectBox.java

@@ -0,0 +1,101 @@
+// Copyright (C) 2013 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.client.ui;
+
+import com.google.gerrit.client.projects.ProjectApi;
+import com.google.gerrit.client.projects.ProjectInfo;
+import com.google.gerrit.client.rpc.Natives;
+import com.google.gerrit.reviewdb.client.Project;
+import com.google.gwt.core.client.JsArray;
+import com.google.gwt.user.client.rpc.AsyncCallback;
+import com.google.gwt.user.client.ui.Composite;
+import com.google.gwt.user.client.ui.SuggestBox;
+import com.google.gwtexpui.globalkey.client.NpTextBox;
+
+import java.util.HashSet;
+import java.util.Set;
+
+public class ParentProjectBox extends Composite {
+  private final NpTextBox textBox;
+  private final SuggestBox suggestBox;
+  private final ParentProjectNameSuggestOracle suggestOracle;
+
+  public ParentProjectBox() {
+    textBox = new NpTextBox();
+    suggestOracle = new ParentProjectNameSuggestOracle();
+    suggestBox = new SuggestBox(suggestOracle, textBox);
+    initWidget(suggestBox);
+  }
+
+  public void setVisibleLength(int len) {
+    textBox.setVisibleLength(len);
+  }
+
+  public void setProject(final Project.NameKey project) {
+    suggestOracle.setProject(project);
+  }
+
+  public void setParentProject(final Project.NameKey parent) {
+    suggestBox.setText(parent != null ? parent.get() : "");
+  }
+
+  public Project.NameKey getParentProjectName() {
+    final String projectName = suggestBox.getText().trim();
+    if (projectName.isEmpty()) {
+      return null;
+    }
+    return new Project.NameKey(projectName);
+  }
+
+  private static class ParentProjectNameSuggestOracle extends ProjectNameSuggestOracle {
+    private Set<String> exclude = new HashSet<String>();
+
+    public void setProject(Project.NameKey project) {
+      exclude.clear();
+      exclude.add(project.get());
+      ProjectApi.getChildren(project, true, new AsyncCallback<JsArray<ProjectInfo>>() {
+        @Override
+        public void onSuccess(JsArray<ProjectInfo> result) {
+          for (ProjectInfo p : Natives.asList(result)) {
+            exclude.add(p.name());
+          }
+        }
+
+        @Override
+        public void onFailure(Throwable caught) {
+        }
+      });
+    }
+
+    @Override
+    public void _onRequestSuggestions(Request req, final Callback callback) {
+      super._onRequestSuggestions(req, new Callback() {
+        public void onSuggestionsReady(Request request, Response response) {
+          if (exclude.size() > 0) {
+            Set<Suggestion> filteredSuggestions =
+                new HashSet<Suggestion>(response.getSuggestions());
+            for (Suggestion s : response.getSuggestions()) {
+              if (exclude.contains(s.getReplacementString())) {
+                filteredSuggestions.remove(s);
+              }
+            }
+            response.setSuggestions(filteredSuggestions);
+          }
+          callback.onSuggestionsReady(request, response);
+        }
+      });
+    }
+  }
+}