Improve Update Project notification: oneline & with filter info

Mention just the whole number of affected files, no matter whether they were added, modified or deleted. This information is not critical in this place and, if needed, can be achieved from the update project tree.
This makes the notification oneline: IDEA-172375

If there is a scope filter, calculate the number of files under this filter, to let user know if he needs to view updated files at all: IDEA-172015.

platform/vcs-impl/src/com/intellij/openapi/vcs/update/AbstractCommonUpdateAction.java

@@ -41,6 +41,7 @@ import com.intellij.openapi.vcs.ex.ProjectLevelVcsManagerEx;
 import com.intellij.openapi.vfs.VfsUtilCore;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.openapi.vfs.VirtualFileManager;
+import com.intellij.psi.search.scope.packageSet.NamedScope;
 import com.intellij.util.WaitForProgressToShow;
 import com.intellij.util.containers.MultiMap;
 import com.intellij.util.ui.OptionsDialog;
@@ -54,7 +55,6 @@ import java.io.File;
 import java.util.*;
 
 import static com.intellij.openapi.util.text.StringUtil.pluralize;
-import static com.intellij.openapi.util.text.StringUtil.toLowerCase;
 import static com.intellij.openapi.vcs.VcsNotifier.STANDARD_NOTIFICATION;
 import static com.intellij.util.ObjectUtils.notNull;
 
@@ -416,25 +416,24 @@ public abstract class AbstractCommonUpdateAction extends AbstractVcsAction {
       });
     }
 
-    private String prepareNotificationWithUpdateInfo() {
-      StringBuffer text = new StringBuffer();
-      final List<FileGroup> groups = myUpdatedFiles.getTopLevelGroups();
-      for (FileGroup group : groups) {
-        appendGroup(text, group);
-      }
-      return text.toString();
-    }
-
-    private void appendGroup(final StringBuffer text, final FileGroup group) {
-      final int s = group.getFiles().size();
-      if (s > 0) {
-        text.append(s).append(" ").append(pluralize("File", s)).append(" ").append(toLowerCase(group.getUpdateName())).append("<br/>");
+    @NotNull
+    private String prepareNotificationWithUpdateInfo(@NotNull UpdateInfoTree tree) {
+      String scopeText = "";
+      NamedScope scopeFilter = tree.getFilterScope();
+      if (scopeFilter != null) {
+        int filteredFiles = tree.getFilesCount(true);
+        String filterName = scopeFilter.getName();
+        if (filteredFiles == 0) {
+          scopeText = filterName + " wasn't modified";
+        }
+        else {
+          scopeText = "In " + filterName + ": " + filteredFiles + " " + pluralize("file", filteredFiles) + " modified";
+        }
+        scopeText += "<br/>In all scopes: ";
       }
 
-      final List<FileGroup> list = group.getChildren();
-      for (FileGroup g : list) {
-        appendGroup(text, g);
-      }
+      int allFiles = tree.getFilesCount(false);
+      return scopeText + allFiles + " " + pluralize("file", allFiles) + " modified";
     }
 
     @Override
@@ -533,8 +532,8 @@ public abstract class AbstractCommonUpdateAction extends AbstractVcsAction {
             title = "Project Updated";
             type = NotificationType.INFORMATION;
           }
-          
-          Notification notification = STANDARD_NOTIFICATION.createNotification(title, prepareNotificationWithUpdateInfo(), type, null);
+
+          Notification notification = STANDARD_NOTIFICATION.createNotification(title, prepareNotificationWithUpdateInfo(tree), type, null);
           notification.addAction(new ViewUpdateInfoNotification(myProject, tree, "View"));
           VcsNotifier.getInstance(myProject).notify(notification);
         }

platform/vcs-impl/src/com/intellij/openapi/vcs/update/FileTreeNode.java

@@ -25,6 +25,7 @@ import com.intellij.psi.search.scope.packageSet.PackageSetBase;
 import com.intellij.ui.SimpleTextAttributes;
 import com.intellij.util.PlatformIcons;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import javax.swing.*;
 import java.io.File;
@@ -55,14 +56,14 @@ public class FileTreeNode extends FileOrDirectoryTreeNode {
   }
 
   @Override
-  protected boolean acceptFilter(Pair<PackageSetBase, NamedScopesHolder> filter, boolean showOnlyFilteredItems) {
+  protected boolean acceptFilter(@Nullable Pair<PackageSetBase, NamedScopesHolder> filter, boolean showOnlyFilteredItems) {
     try {
       VirtualFilePointer filePointer = getFilePointer();
       if (!filePointer.isValid()) {
         return false;
       }
       VirtualFile file = filePointer.getFile();
-      if (file != null && file.isValid() && filter.first.contains(file, getProject(), filter.second)) {
+      if (file != null && file.isValid() && filter != null && filter.first.contains(file, getProject(), filter.second)) {
         applyFilter(true);
         return true;
       }

platform/vcs-impl/src/com/intellij/openapi/vcs/update/UpdateInfoTree.java

@@ -114,7 +114,7 @@ public class UpdateInfoTree extends PanelWithActionsAndCloseButton {
     myProject = project;
     myUpdatedFiles = updatedFiles;
     myRootName = rootName;
-    
+
     myShowOnlyFilteredItems = VcsConfiguration.getInstance(myProject).UPDATE_FILTER_BY_SCOPE;
 
     myFileStatusManager = FileStatusManager.getInstance(myProject);
@@ -358,6 +358,20 @@ public class UpdateInfoTree extends PanelWithActionsAndCloseButton {
     return result.toArray(new File[result.size()]);
   }
 
+  int getFilesCount(boolean filtered) {
+    Pair<PackageSetBase, NamedScopesHolder> scopeFilter = getScopeFilter();
+    int[] result = new int[1];
+    TreeUtil.traverse(myRoot, node -> {
+      if (node instanceof FileTreeNode) {
+        if (!filtered || ((FileTreeNode)node).acceptFilter(scopeFilter, true)) {
+          result[0]++;
+        }
+      }
+      return true;
+    });
+    return result[0];
+  }
+
   public void expandRootChildren() {
     TreeNode root = (TreeNode)myTreeModel.getRoot();
 
@@ -449,7 +463,7 @@ public class UpdateInfoTree extends PanelWithActionsAndCloseButton {
 
   @Nullable
   private Pair<PackageSetBase, NamedScopesHolder> getScopeFilter() {
-    String scopeName = VcsConfiguration.getInstance(myProject).UPDATE_FILTER_SCOPE_NAME;
+    String scopeName = getFilterScopeName();
     if (scopeName != null) {
       for (NamedScopesHolder holder : NamedScopesHolder.getAllNamedScopeHolders(myProject)) {
         NamedScope scope = holder.getScope(scopeName);
@@ -464,6 +478,17 @@ public class UpdateInfoTree extends PanelWithActionsAndCloseButton {
     return null;
   }
 
+  @Nullable
+  private String getFilterScopeName() {
+    return VcsConfiguration.getInstance(myProject).UPDATE_FILTER_SCOPE_NAME;
+  }
+
+  @Nullable
+  NamedScope getFilterScope() {
+    Pair<PackageSetBase, NamedScopesHolder> filter = getScopeFilter();
+    return filter == null ? null : filter.second.getScope(getFilterScopeName());
+  }
+
   private class FilterAction extends ToggleAction implements DumbAware {
     public FilterAction() {
       super("Scope Filter", VcsBundle.getString("settings.filter.update.project.info.by.scope"), AllIcons.General.Filter);
@@ -483,7 +508,7 @@ public class UpdateInfoTree extends PanelWithActionsAndCloseButton {
 
     public void update(AnActionEvent e) {
       super.update(e);
-      e.getPresentation().setEnabled(!myGroupByChangeList && VcsConfiguration.getInstance(myProject).UPDATE_FILTER_SCOPE_NAME != null);
+      e.getPresentation().setEnabled(!myGroupByChangeList && getFilterScopeName() != null);
     }
   }