**   Copyright notice                                                       **

**                                                                          **

**   (c) 2005-2006 RSSOwl Development Team                                  **

**   http://www.rssowl.org/                                                 **

**                                                                          **

**   All rights reserved                                                    **

**                                                                          **

**   This program and the accompanying materials are made available under   **

**   the terms of the Eclipse Public License v1.0 which accompanies this    **

**   distribution, and is available at:                                     **

**   http://www.rssowl.org/legal/epl-v10.html                               **

**                                                                          **

**   A copy is found in the file epl-v10.html and important notices to the  **

**   license from the team is found in the textfile LICENSE.txt distributed **

**   in this package.                                                       **

**                                                                          **

**   This copyright notice MUST APPEAR in all copies of the file!           **

**                                                                          **

**   Contributors:                                                          **

**     RSSOwl Development Team - initial API and implementation             **

**                                                                          **

**  **********************************************************************  */

* The <code>SearchNewsDialog</code> allows to define a number of

* <code>ISearchCondition</code>s to search in all News. The result is given

* out in a Table-Control below.

* <p>

* TODO Unfortunately this Dialog copies a lot of existing code from

* NewsTableControl

* </p>

*

* @author bpasero

*/

  /* Min width of the dialog in DLUs */

  private static final int DIALOG_MIN_WIDTH = 500;

  /* Sash Weights when Preview is invisible */

  private static final int[] TWO_SASH_WEIGHTS = new int[] { 40, 60, 0 };

  /* Sash Weights when Preview is visible */

  private static final int[] THREE_SASH_WEIGHTS = new int[] { 33, 33, 33 };

  /* Section for Dialogs Settings */

  private static final String SETTINGS_SECTION = "org.rssowl.ui.internal.dialogs.SearchNewsDialog";

  /* Preference: Sash Weights */

  private static final String PREF_SASH_WEIGHTS = "org.rssowl.ui.internal.dialogs.search.SashWeights";

  /* Preference: Column Order */

  private static final String PREF_COL_ORDER = "org.rssowl.ui.internal.dialogs.search.ColumnOrder";

  /* ID to associate a Column with its ID */

  private static final String COL_ID = "org.rssowl.ui.internal.editors.feed.ColumnIdentifier";

  /* Workaround for unknown Dateo-Col Width */

  private static int DATE_COL_WIDTH = -1;

  /* Number of News to preload before showing as result */

  private static final int NUM_PRELOADED = 20;

  /* Count number of open Dialogs */

  private static int fgOpenDialogCount;

  /* A Set of Stop Words in English */

  private static final Set<String> STOP_WORDS = Collections.synchronizedSet(new HashSet<String>(Arrays.asList(StringUtils.ENGLISH_STOP_WORDS)));

  /* Button IDs */

  private static final int BUTTON_SEARCH = 1000;

  private static final int BUTTON_CLEAR = 1001;

  /* TODO Developer's flag to enable / disable COD */

  private static final boolean USE_CUSTOM_OWNER_DRAWN = true;

  /* Indices of Columns in the Table-Viewer */

  private static final int COL_RELEVANCE = 0;

  private static final int COL_TITLE = 1;

  private static final int COL_FEED = 2;

  private static final int COL_CATEGORY = 5;

  private static final int COL_STICKY = 6;

  /* Viewer and Controls */

  private Button fMatchAllRadio;

  private Button fMatchAnyRadio;

  private SearchConditionList fSearchConditionList;

  private TableViewer fResultViewer;

  private ScoredNewsComparator fNewsSorter;

  private Link fStatusLabel;

  private NewsBrowserViewer fBrowserViewer;

  private int[] fCachedWeights;

  private int[] fCachedColumnOrder;

  /* Misc. */

  private NewsTableControl.Columns fInitialSortColumn = NewsTableControl.Columns.SCORE;

  private boolean fInitialAscending;

  private LocalResourceManager fResources;

  private IDialogSettings fDialogSettings;

  private IModelSearch fModelSearch;

  private NewsListener fNewsListener;

  private boolean fFirstTimeOpen;

  private boolean fShowsHandCursor;

  private Cursor fHandCursor;

  private List<ISearchCondition> fInitialConditions;

  private boolean fRunSearch;

  private boolean fMatchAllConditions;

  private INewsDAO fNewsDao;

  private IPreferenceScope fPreferences;

  private LabelAdapter fLabelListener;

  private boolean fIsPreviewVisible;

  private SashForm fSashForm;

  private Composite fBottomSash;

  private List<ISearchCondition> fCurrentSearchConditions;

  /* Container for a search result */

  private static class ScoredNews {

    private NewsReference fNewsRef;

    private INews fResolvedNews;

    private Float fScore;

    private Relevance fRelevance;

    private final State fState;

    ScoredNews(NewsReference newsRef, INews.State state, Float score, Relevance relevance) {

      fNewsRef = newsRef;

      fState = state;

      fScore = score;

      fRelevance = relevance;

    }

    INews getNews() {

      if (fResolvedNews == null)

        fResolvedNews = fNewsRef.resolve();

      return fResolvedNews;

    }

    INews.State getState() {

      return fState;

    }

    NewsReference getNewsReference() {

      return fNewsRef;

    }

    Float getScore() {

      return fScore;

    }

    Relevance getRelevance() {

      return fRelevance;

    }

  }

  /* ScoredNews Relevance */

  private enum Relevance {

    /** Indicates Low Relevance */

    LOW,

    /** Indicates Medium Relevance */

    MEDIUM,

    /** Indicates High Relevance */

    HIGH;

  }

  /* Comparator for Scored News */

  private static class ScoredNewsComparator extends ViewerComparator implements Comparator<ScoredNews> {

    private NewsComparator fNewsComparator = new NewsComparator();

    /*

     * @see org.eclipse.jface.viewers.ViewerComparator#compare(org.eclipse.jface.viewers.Viewer,

     * java.lang.Object, java.lang.Object)

     */

    @Override

    public int compare(Viewer viewer, Object e1, Object e2) {

      /* Unlikely to happen */

      if (!(e1 instanceof ScoredNews) || !(e2 instanceof ScoredNews))

        return 0;

      /* Proceed comparing Scored News */

      return compare((ScoredNews) e1, (ScoredNews) e2);

    }

    /*

     * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object)

     */

    public int compare(ScoredNews news1, ScoredNews news2) {

      /* Not sorting by Score */

      if (fNewsComparator.getSortBy() != NewsTableControl.Columns.SCORE)

        return fNewsComparator.compare(news1.getNews(), news2.getNews());

      /* Sort by Score */

      if (!news1.getScore().equals(news2.getScore())) {

        int result = news1.getScore().compareTo(news2.getScore());

        return fNewsComparator.isAscending() ? result : result * -1;

      }

      /* Default: Sort by Date */

      Date date1 = DateUtils.getRecentDate(news1.getNews());

      Date date2 = DateUtils.getRecentDate(news2.getNews());

      return date2.compareTo(date1);

    }

    void setAscending(boolean ascending) {

      fNewsComparator.setAscending(ascending);

    }

    void setSortBy(Columns sortColumn) {

      fNewsComparator.setSortBy(sortColumn);

    }

    Columns getSortBy() {

      return fNewsComparator.getSortBy();

    }

    boolean isAscending() {

      return fNewsComparator.isAscending();

    }

  }

  /* LabelProvider for Scored News */

  private static class ScoredNewsLabelProvider extends NewsTableLabelProvider {

    private Image fHighRelevanceIcon;

    private Image fMediumRelevanceIcon;

    private Image fLowRelevanceIcon;

    ScoredNewsLabelProvider(StructuredViewer viewer) {

      super(viewer);

      createResources();

    }

    private void createResources() {

      fHighRelevanceIcon = OwlUI.getImage(fResources, "icons/obj16/high.gif");

      fMediumRelevanceIcon = OwlUI.getImage(fResources, "icons/obj16/medium.gif");

      fLowRelevanceIcon = OwlUI.getImage(fResources, "icons/obj16/low.gif");

    }

    /*

     * @see org.eclipse.jface.viewers.OwnerDrawLabelProvider#update(org.eclipse.jface.viewers.ViewerCell)

     */

    @Override

    public void update(ViewerCell cell) {

      ScoredNews scoredNews = (ScoredNews) cell.getElement();

      /* Text */

      if (cell.getColumnIndex() == COL_CATEGORY)

        cell.setText(getCategories(scoredNews.getNews()));

      else

        cell.setText(getColumnText(scoredNews.getNews(), cell.getColumnIndex() - 1));

      /* Image */

      cell.setImage(getColumnImage(scoredNews, cell.getColumnIndex()));

      /* Font */

      cell.setFont(getFont(scoredNews.getNews(), cell.getColumnIndex() - 1));

      /* Foreground */

      Color foreground = getForeground(scoredNews.getNews(), cell.getColumnIndex() - 1);

      /* TODO This is required to invalidate + redraw the entire TableItem! */

      if (USE_CUSTOM_OWNER_DRAWN) {

        Item item = (Item) cell.getItem();

        if (item instanceof TableItem)

          ((TableItem) cell.getItem()).setForeground(foreground);

      } else

        cell.setForeground(foreground);

      /* Background */

      cell.setBackground(getBackground(scoredNews.getNews(), cell.getColumnIndex() - 1));

    }

    private String getCategories(INews news) {

      StringBuilder builder = new StringBuilder();

      List<ICategory> categories = news.getCategories();

      for (ICategory category : categories) {

        if (category.getName() != null)

          builder.append(category.getName()).append(", ");

        else if (category.getDomain() != null)

          builder.append(category.getDomain()).append(", ");

      }

      if (builder.length() > 0)

        return builder.substring(0, builder.length() - 2);

      return builder.toString();

    }

    /*

     * @see org.rssowl.ui.internal.editors.feed.NewsTableLabelProvider#getColumnImage(java.lang.Object,

     * int)

     */

    @Override

    protected Image getColumnImage(Object element, int columnIndex) {

      /* Relevance Column */

      if (columnIndex == COL_RELEVANCE) {

        ScoredNews scoredNews = (ScoredNews) element;

        switch (scoredNews.getRelevance()) {

          case HIGH:

            return fHighRelevanceIcon;

          case MEDIUM:

            return fMediumRelevanceIcon;

          case LOW:

            return fLowRelevanceIcon;

        }

      }

      /* Any other Column */

      return super.getColumnImage(((ScoredNews) element).getNews(), columnIndex - 1);

    }

    /*

     * @see org.eclipse.jface.viewers.CellLabelProvider#getToolTipText(java.lang.Object)

     */

    @Override

    public String getToolTipText(Object element) {

      ScoredNews scoredNews = (ScoredNews) element;

      FeedLinkReference feedRef = scoredNews.getNews().getFeedReference();

      IBookMark bookMark = Controller.getDefault().getCacheService().getBookMark(feedRef);

      if (bookMark != null)

        return bookMark.getName();

      return null;

    }

    /*

     * @see org.rssowl.ui.internal.editors.feed.NewsTableLabelProvider#erase(org.eclipse.swt.widgets.Event,

     * java.lang.Object)

     */

    @Override

    public void erase(Event event, Object element) {

      super.erase(event, ((ScoredNews) element).getNews());

    }

    /*

     * @see org.rssowl.ui.internal.editors.feed.NewsTableLabelProvider#paint(org.eclipse.swt.widgets.Event,

     * java.lang.Object)

     */

    @Override

    protected void paint(Event event, Object element) {

      super.paint(event, ((ScoredNews) element).getNews());

    }

    /*

     * @see org.rssowl.ui.internal.editors.feed.NewsTableLabelProvider#measure(org.eclipse.swt.widgets.Event,

     * java.lang.Object)

     */

    @Override

    protected void measure(Event event, Object element) {

      super.measure(event, ((ScoredNews) element).getNews());

    }

  }

  /* Custom Tooltip Support for Feed Column */

  private static class FeedColumnToolTipSupport extends ColumnViewerToolTipSupport {

    FeedColumnToolTipSupport(ColumnViewer viewer, int style) {

      super(viewer, style, false);

    }

    /*

     * @see org.eclipse.jface.viewers.ColumnViewerToolTipSupport#getToolTipArea(org.eclipse.swt.widgets.Event)

     */

    @Override

    protected Object getToolTipArea(Event event) {

      Table table = (Table) event.widget;

      Point point = new Point(event.x, event.y);

      TableItem item = table.getItem(point);

      /* Only valid for Feed Column */

      if (item != null) {

        if (item.getBounds(COL_FEED).contains(point))

          return super.getToolTipArea(event);

      }

      return null;

    }

    public static void enableFor(ColumnViewer viewer) {

      new FeedColumnToolTipSupport(viewer, ToolTip.NO_RECREATE);

    }

  }

  /**

   * @param parentShell

   */

  public SearchNewsDialog(Shell parentShell) {

    this(parentShell, null, true, false);

  }

  /**

   * @param parentShell

   * @param searchScope

   */

  public SearchNewsDialog(Shell parentShell, List<IFolderChild> searchScope) {

    this(parentShell, toSearchConditions(searchScope), true, false);

  }

  private static List<ISearchCondition> toSearchConditions(List<IFolderChild> searchScope) {

    IModelFactory factory = Owl.getModelFactory();

    List<ISearchCondition> conditions = new ArrayList<ISearchCondition>(2);

    /* Add scope as condition if provided */

    if (!searchScope.isEmpty()) {

      ISearchField field = factory.createSearchField(INews.LOCATION, INews.class.getName());

      conditions.add(factory.createSearchCondition(field, SearchSpecifier.IS, ModelUtils.toPrimitive(searchScope)));

    }

    /* Add default condition as well */

    ISearchField field = factory.createSearchField(IEntity.ALL_FIELDS, INews.class.getName());

    conditions.add(factory.createSearchCondition(field, SearchSpecifier.CONTAINS, ""));

    return conditions;

  }

  /**

   * @param parentShell

   * @param initialConditions A List of Conditions that should show initially.

   * @param matchAllConditions If <code>TRUE</code>, require all conditions

   * to match, <code>FALSE</code> otherwise.

   * @param runSearch If <code>TRUE</code>, run the search after the dialog

   * opened.

   */

  public SearchNewsDialog(Shell parentShell, List<ISearchCondition> initialConditions, boolean matchAllConditions, boolean runSearch) {

    super(parentShell);

    fPreferences = Owl.getPreferenceService().getGlobalScope();

    fResources = new LocalResourceManager(JFaceResources.getResources());

    fDialogSettings = Activator.getDefault().getDialogSettings();

    fFirstTimeOpen = (fDialogSettings.getSection(SETTINGS_SECTION) == null);

    fIsPreviewVisible = fPreferences.getBoolean(DefaultPreferences.SEARCH_DIALOG_PREVIEW_VISIBLE);

    fCachedWeights = fPreferences.getIntegers(PREF_SASH_WEIGHTS);

    fCachedColumnOrder = fPreferences.getIntegers(PREF_COL_ORDER);

    fModelSearch = Owl.getPersistenceService().getModelSearch();

    fHandCursor = parentShell.getDisplay().getSystemCursor(SWT.CURSOR_HAND);

    fInitialConditions = initialConditions;

    fMatchAllConditions = matchAllConditions;

    fRunSearch = runSearch;

    fNewsDao = DynamicDAO.getDAO(INewsDAO.class);

  }

  /*

   * @see org.eclipse.jface.window.Window#open()

   */

  @Override

  public int open() {

    fgOpenDialogCount++;

    return super.open();

  }

  /*

   * @see org.eclipse.jface.dialogs.TrayDialog#close()

   */

  @Override

  public boolean close() {

    fgOpenDialogCount--;

    /* Store Preferences */

    fPreferences.putBoolean(DefaultPreferences.SEARCH_DIALOG_PREVIEW_VISIBLE, fIsPreviewVisible);

    if (fCachedWeights != null)

      fPreferences.putIntegers(PREF_SASH_WEIGHTS, fCachedWeights);

    if (fCachedColumnOrder != null)

      fPreferences.putIntegers(PREF_COL_ORDER, fCachedColumnOrder);

    /*

     * Workaround for Eclipse Bug 186025: The Virtual Manager is not cleared

     * when the TableViewer is disposed. Due to the hookListener() call, a

     * reference to the TableViewer is held in Memory, so we need to explicitly

     * clear the virtual manager.

     */

    fResultViewer.setItemCount(0);

    boolean res = super.close();

    fResources.dispose();

    unregisterListeners();

    return res;

  }

  /*

   * @see org.eclipse.jface.window.Window#configureShell(org.eclipse.swt.widgets.Shell)

   */

  @Override

  protected void configureShell(Shell shell) {

    super.configureShell(shell);

    shell.setText("Search News");

  }

  /*

   * @see org.eclipse.jface.dialogs.Dialog#create()

   */

  @Override

  public void create() {

    super.create();

    /* Perform the search slightly delayed if requested */

    if (fRunSearch) {

      JobRunner.runInUIThread(200, getShell(), new Runnable() {

        public void run() {

          onSearch();

        }

      });

    }

  }

  /*

   * @see org.eclipse.jface.dialogs.TitleAreaDialog#createDialogArea(org.eclipse.swt.widgets.Composite)

   */

  @Override

  protected Control createDialogArea(Composite parent) {

    /* Separator */

    new Label(parent, SWT.SEPARATOR | SWT.HORIZONTAL).setLayoutData(new GridData(SWT.FILL, SWT.BEGINNING, true, false));

    /* Title Image */

    setTitleImage(OwlUI.getImage(fResources, "icons/wizban/search.gif"));

    /* Title Message */

    setMessage("You can use \'?\' for any character and \'*\' for any number of characters in your search.", IMessageProvider.INFORMATION);

    /* Sashform dividing search definition from results */

    fSashForm = new SashForm(parent, SWT.VERTICAL | SWT.SMOOTH);

    fSashForm.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true, 2, 1));

    fSashForm.setBackground(parent.getDisplay().getSystemColor(SWT.COLOR_WHITE));

    /* Top Area */

    Composite topSash = new Composite(fSashForm, SWT.NONE);

    topSash.setLayout(LayoutUtils.createGridLayout(1, 0, 0, 0, 0, false));

    Composite topSashContent = new Composite(topSash, SWT.None);

    topSashContent.setLayout(LayoutUtils.createGridLayout(2, 0, 0, 0, 0, false));

    topSashContent.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));

    /* Create Condition Controls */

    createConditionControls(topSashContent);

    /* Create Center Sash */

    Composite centerSash = new Composite(fSashForm, SWT.NONE);

    centerSash.setLayout(LayoutUtils.createGridLayout(1, 0, 0, 0, 0, false));

    centerSash.addControlListener(new ControlAdapter() {

      @Override

      public void controlResized(ControlEvent e) {

        fCachedWeights = fSashForm.getWeights();

      }

    });

    /* Separator */

    new Label(centerSash, SWT.SEPARATOR | SWT.HORIZONTAL).setLayoutData(new GridData(SWT.FILL, SWT.END, true, false));

    Composite centerSashContent = new Composite(centerSash, SWT.None);

    centerSashContent.setLayout(LayoutUtils.createGridLayout(1, 0, 0, 0, 0, false));

    centerSashContent.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));

    /* Create Viewer for Results */

    createResultViewer(centerSashContent);

    /* Create Bottom Sash */

    fBottomSash = new Composite(fSashForm, SWT.NONE);

    fBottomSash.setLayout(LayoutUtils.createGridLayout(1, 0, 0, 0, 0, false));

    fBottomSash.setVisible(fIsPreviewVisible);

    Composite bottomSashContent = new Composite(fBottomSash, SWT.None);

    bottomSashContent.setLayout(LayoutUtils.createGridLayout(1, 0, 0, 0, 0, false));

    bottomSashContent.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));

    bottomSashContent.setBackground(bottomSashContent.getDisplay().getSystemColor(SWT.COLOR_WHITE));

    /* Create Viewer for News Item */

    createBrowserViewer(bottomSashContent);

    /* Set weight to SashForm */

    if (fCachedWeights != null)

      fSashForm.setWeights(fCachedWeights);

    else

      fSashForm.setWeights(fIsPreviewVisible ? THREE_SASH_WEIGHTS : TWO_SASH_WEIGHTS);

    /* Separator */

    new Label(fBottomSash, SWT.SEPARATOR | SWT.HORIZONTAL).setLayoutData(new GridData(SWT.FILL, SWT.END, true, false));

    return fSashForm;

  }

  private void createBrowserViewer(Composite bottomSashContent) {

    fBrowserViewer = new NewsBrowserViewer(bottomSashContent, SWT.NONE) {

      @Override

      protected List<String> getHighlightedWords() {

        List<String> words = new ArrayList<String>(fCurrentSearchConditions.size());

        /* Check Search Conditions for String-Values */

        for (ISearchCondition cond : fCurrentSearchConditions) {

          if (cond.getValue() instanceof String) {

            String value = cond.getValue().toString();

            /* TODO Wildcards are not yet supported */

            if (value.contains("?") || value.contains("*"))

              continue;

            /* Split into Words */

            StringTokenizer tokenizer = new StringTokenizer(value);

            while (tokenizer.hasMoreElements()) {

              String nextWord = tokenizer.nextElement().toString().toLowerCase();

              /* But ignore Stop Words */

              if (!STOP_WORDS.contains(nextWord) && !words.contains(nextWord))

                words.add(nextWord);

            }

          }

        }

        return words;

      }

    };

    fBrowserViewer.getControl().setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));

    /* Create Content Provider */

    fBrowserViewer.setContentProvider(new IStructuredContentProvider() {

      public Object[] getElements(Object inputElement) {

        if (inputElement instanceof Object[] && ((Object[]) inputElement).length > 0)

          inputElement = ((Object[]) inputElement)[0];

        if (inputElement instanceof NewsReference)

          return new Object[] { ((NewsReference) inputElement).resolve() };

        return new Object[] { inputElement };

      }

      public void dispose() {}

      public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {}

    });

    /* Create LabelProvider */

    fBrowserViewer.setLabelProvider(new NewsBrowserLabelProvider(fBrowserViewer));

    /* Set input when selection in result viewer changes */

    fResultViewer.addSelectionChangedListener(new ISelectionChangedListener() {

      public void selectionChanged(SelectionChangedEvent event) {

        IStructuredSelection selection = (IStructuredSelection) event.getSelection();

        if (!selection.isEmpty() && fIsPreviewVisible) {

          fBrowserViewer.setInput(selection.getFirstElement());

          hideBrowser(false);

        }

      }

    });

  }

  private void createConditionControls(Composite container) {

    Composite topControlsContainer = new Composite(container, SWT.None);

    topControlsContainer.setLayoutData(new GridData(SWT.FILL, SWT.BEGINNING, true, false, 2, 1));

    topControlsContainer.setLayout(LayoutUtils.createGridLayout(3, 10, 0));

    /* Radio to select Condition Matching */

    fMatchAllRadio = new Button(topControlsContainer, SWT.RADIO);

    fMatchAllRadio.setText("&Match all conditions");

    fMatchAllRadio.setSelection(fMatchAllConditions);

    fMatchAnyRadio = new Button(topControlsContainer, SWT.RADIO);

    fMatchAnyRadio.setText("Match any c&ondition");

    fMatchAnyRadio.setSelection(!fMatchAllConditions);

    /* ToolBar to add and select existing saved searches */

    final ToolBarManager dialogToolBar = new ToolBarManager(SWT.RIGHT | SWT.FLAT);

    /* Toggle Preview */

    final String previewActionId = "org.rssowl.ui.internal.dialogs.search.PreviewAction";

    IAction previewAction = new Action("&Preview Results", IAction.AS_CHECK_BOX) {

      @Override

      public void run() {

        fIsPreviewVisible = !fIsPreviewVisible;

        fSashForm.setWeights(fIsPreviewVisible ? THREE_SASH_WEIGHTS : TWO_SASH_WEIGHTS);

        fBottomSash.setVisible(fIsPreviewVisible);

        fSashForm.layout();

        dialogToolBar.find(previewActionId).update(IAction.TOOL_TIP_TEXT);

        /* Select and Show News if required */

        if (fIsPreviewVisible && fResultViewer.getTable().getItemCount() > 0) {

          /* Select first News if required */

          if (fResultViewer.getSelection().isEmpty())

            fResultViewer.getTable().select(0);

          /* Set input and Focus */

          fBrowserViewer.setInput(((IStructuredSelection) fResultViewer.getSelection()).getFirstElement());

          hideBrowser(false);

          fResultViewer.getTable().setFocus();

          /* Make sure to show the selection */

          fResultViewer.getTable().showSelection();

        }

      }

      @Override

      public ImageDescriptor getImageDescriptor() {

        return OwlUI.getImageDescriptor("icons/etool16/highlight.gif");

      }

      @Override

      public String getToolTipText() {

        if (fIsPreviewVisible)

          return "Hide Preview";

        return "Show Preview";

      }

    };

    previewAction.setId(previewActionId);

    previewAction.setChecked(fIsPreviewVisible);

    dialogToolBar.add(previewAction);

    /* Separator */

    dialogToolBar.add(new Separator());

    /* Existing Saved Searches */

    IAction savedSearches = new Action("S&aved Searches", IAction.AS_DROP_DOWN_MENU) {

      @Override

      public void run() {

        getMenuCreator().getMenu(dialogToolBar.getControl()).setVisible(true);

      }

      @Override

      public ImageDescriptor getImageDescriptor() {

        return OwlUI.SEARCHMARK;

      }

    };

    savedSearches.setMenuCreator(new IMenuCreator() {

      public void dispose() {}

      public Menu getMenu(Control parent) {

        Set<ISearchMark> searchMarks = Controller.getDefault().getCacheService().getSearchMarks();

        Menu menu = new Menu(parent);

        /* Create new Saved Search */

        MenuItem newSavedSearch = new MenuItem(menu, SWT.NONE);

        newSavedSearch.setText("New Saved Search...");

        newSavedSearch.setImage(OwlUI.getImage(fResources, "icons/etool16/add.gif"));

        newSavedSearch.addSelectionListener(new SelectionAdapter() {

          @Override

          public void widgetSelected(SelectionEvent e) {

            onSave();

          }

        });

        /* Separator */

        if (searchMarks.size() > 0)

          new MenuItem(menu, SWT.SEPARATOR);

        /* Show Existing Saved Searches */

        for (final ISearchMark searchMark : searchMarks) {

          MenuItem item = new MenuItem(menu, SWT.None);

          item.setText(searchMark.getName());

          item.setImage(OwlUI.getImage(fResources, OwlUI.SEARCHMARK));

          item.addSelectionListener(new SelectionAdapter() {

            @Override

            public void widgetSelected(SelectionEvent e) {

              show(searchMark);

            }

          });

        }

        return menu;

      }

      public Menu getMenu(Menu parent) {

        return null;

      }

    });

    dialogToolBar.add(savedSearches);

    dialogToolBar.createControl(topControlsContainer);

    dialogToolBar.getControl().setLayoutData(new GridData(SWT.END, SWT.BEGINNING, true, false));

    dialogToolBar.getControl().getItem(0).setText(previewAction.getText());

    dialogToolBar.getControl().getItem(2).setText(savedSearches.getText());

    /* Container for Conditions */

    final Composite conditionsContainer = new Composite(container, SWT.NONE);

    conditionsContainer.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true, 2, 1));

    conditionsContainer.setLayout(LayoutUtils.createGridLayout(2, 5, 10));

    conditionsContainer.setBackground(container.getDisplay().getSystemColor(SWT.COLOR_WHITE));

    conditionsContainer.setBackgroundMode(SWT.INHERIT_FORCE);

    conditionsContainer.addPaintListener(new PaintListener() {

      public void paintControl(PaintEvent e) {

        GC gc = e.gc;

        Rectangle clArea = conditionsContainer.getClientArea();

        gc.setForeground(conditionsContainer.getDisplay().getSystemColor(SWT.COLOR_GRAY));

        gc.drawLine(clArea.x, clArea.y, clArea.x + clArea.width, clArea.y);

      }

    });

    /* Search Conditions List */

    fSearchConditionList = new SearchConditionList(conditionsContainer, SWT.None, getDefaultConditions());

    fSearchConditionList.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true, 2, 1));

    fSearchConditionList.setVisibleItemCount(3);

    /* Show Initial Conditions if present */

    if (fInitialConditions != null)

      fSearchConditionList.showConditions(fInitialConditions);

    /* Focus Input */

    int index = 0;

    if (fInitialConditions != null && fInitialConditions.size() == 2)

      index = 1;

    fSearchConditionList.focusInput(index);

  }

  /* Show conditions of the given searchmark */

  private void show(ISearchMark sm) {

    /* Match Conditions */

    fMatchAllRadio.setSelection(sm.matchAllConditions());

    fMatchAnyRadio.setSelection(!sm.matchAllConditions());

    /* Show Conditions */

    fSearchConditionList.showConditions(sm.getSearchConditions());

    /* Unset Error Message */

    setErrorMessage(null);

  }

  /*

   * @see org.eclipse.jface.dialogs.TrayDialog#createButtonBar(org.eclipse.swt.widgets.Composite)

   */

  @Override

  protected Control createButtonBar(Composite parent) {

    GridLayout layout = new GridLayout(1, false);

    layout.marginWidth = convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_MARGIN);

    layout.marginHeight = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_MARGIN);

    layout.horizontalSpacing = convertHorizontalDLUsToPixels(IDialogConstants.HORIZONTAL_SPACING);

    layout.verticalSpacing = convertVerticalDLUsToPixels(IDialogConstants.VERTICAL_SPACING);

    Composite buttonBar = new Composite(parent, SWT.NONE);

    buttonBar.setLayoutData(new GridData(SWT.FILL, SWT.BEGINNING, true, false));

    buttonBar.setLayout(layout);

    /* Status Label */

    fStatusLabel = new Link(buttonBar, SWT.NONE);

    fStatusLabel.setLayoutData(new GridData(SWT.FILL, SWT.CENTER, true, true));

    ((GridData) fStatusLabel.getLayoutData()).heightHint = 20;

    fStatusLabel.addSelectionListener(new SelectionAdapter() {

      @Override

      public void widgetSelected(SelectionEvent e) {

        onSave();

      }

    });

    /* Search */

    Button searchButton = createButton(buttonBar, BUTTON_SEARCH, "&Search", true);

    ((GridData) searchButton.getLayoutData()).horizontalAlignment = SWT.END;

    ((GridData) searchButton.getLayoutData()).grabExcessHorizontalSpace = false;

    /* Clear */

    createButton(buttonBar, BUTTON_CLEAR, "&Clear", false);

    return buttonBar;

  }

  /*

   * @see org.eclipse.jface.dialogs.Dialog#buttonPressed(int)

   */

  @Override

  protected void buttonPressed(int buttonId) {

    switch (buttonId) {

      case BUTTON_SEARCH:

        onSearch();

        break;

      case BUTTON_CLEAR:

        onClear();

        break;

    }

  }

  private void onSearch() {

    /* Make sure Conditions are provided */

    if (fSearchConditionList.isEmpty()) {

      setErrorMessage("Please specify your search by defining some conditions below.");

      fSearchConditionList.focusInput();

      return;

    }

    /* Unset Error Message */

    setErrorMessage(null);

    /* Create Conditions */

    fCurrentSearchConditions = fSearchConditionList.createConditions();

    final boolean matchAllConditions = fMatchAllRadio.getSelection();

    /* Disable Buttons and update Cursor */

    getButton(BUTTON_SEARCH).setEnabled(false);

    getShell().setCursor(getShell().getDisplay().getSystemCursor(SWT.CURSOR_APPSTARTING));

    JobRunner.runUIUpdater(new UIBackgroundJob(getShell()) {

      private List<ScoredNews> fResult = null;

      @Override

      protected void runInBackground(IProgressMonitor monitor) {

        /* Perform Search in the Background */

        List<SearchHit<NewsReference>> searchHits = fModelSearch.searchNews(fCurrentSearchConditions, matchAllConditions);

        fResult = new ArrayList<ScoredNews>(searchHits.size());

        /* Retrieve maximum raw relevance */

        Float maxRelevanceScore = 0f;

        for (SearchHit<NewsReference> searchHit : searchHits) {

          Float relevanceRaw = searchHit.getRelevance();

          maxRelevanceScore = Math.max(maxRelevanceScore, relevanceRaw);

        }

        /* Calculate Thresholds */

        Float mediumRelThreshold = maxRelevanceScore / 3f * 1f;

        Float highRelThreshold = maxRelevanceScore / 3f * 2f;

        Set<State> visibleStates = State.getVisible();

        /* Fill Results with Relevance */

        for (SearchHit<NewsReference> searchHit : searchHits) {

          /* Only add visible News for now */

          INews.State state = (State) searchHit.getData(INews.STATE);

          if (!visibleStates.contains(state))

            continue;

          /* TODO Have to test if Entity really exists (bug 337) */

          if (!fNewsDao.exists(searchHit.getResult().getId()))

            continue;

          Float relevanceRaw = searchHit.getRelevance();

          Relevance relevance = Relevance.LOW;

          if (relevanceRaw > highRelThreshold)

            relevance = Relevance.HIGH;

          else if (relevanceRaw > mediumRelThreshold)

            relevance = Relevance.MEDIUM;

          /* Add to result */

          fResult.add(new ScoredNews(searchHit.getResult(), state, relevanceRaw, relevance));

        }

        /* Preload some results that are known to be shown initially */

        preload(fResult);

      }

      @Override

      protected void runInUI(IProgressMonitor monitor) {

        /* Set Input (sorted) to Viewer */

        fResultViewer.setInput(fResult);

        /* Update Status Label */

        String text;

        int size = fResult.size();

        if (size == 0)

          text = "The search returned no results. ";

        else if (size == 1)

          text = "The search returned " + fResult.size() + " result. ";

        else

          text = "The search returned " + fResult.size() + " results. ";

        text += "Click <a>here</a> to save this search.";

        fStatusLabel.setText(text);

        /* Enable Buttons and update Cursor */

        getButton(BUTTON_SEARCH).setEnabled(true);

        getShell().setCursor(null);

        getShell().setDefaultButton(getButton(BUTTON_SEARCH));

        getButton(BUTTON_SEARCH).setFocus();

        /* Move Focus back to last Search Condition Element */

        fSearchConditionList.focusInput();

        /* Select First Result if Preview is visible */

        if (fIsPreviewVisible && size > 0) {

          fResultViewer.getTable().select(0);

          fResultViewer.getTable().showSelection();

          /* Set input and Focus */

          Object selection = ((IStructuredSelection) fResultViewer.getSelection()).getFirstElement();

          boolean refresh = selection.equals(fBrowserViewer.getInput());

          fBrowserViewer.setInput(selection);

          hideBrowser(false);

          fResultViewer.getTable().setFocus();

          if (refresh)

            fBrowserViewer.refresh();

        }

        /* Clear Browser Viewer otherwise */

        else if (fIsPreviewVisible)

          hideBrowser(true);

      }

    });

  }

  private void preload(List<ScoredNews> list) {

    for (int i = 0; i < list.size() && i < NUM_PRELOADED; i++) {

      list.get(i).getNews();

    }

  }

  private void hideBrowser(boolean hide) {

    if (hide) {

      fBrowserViewer.setInput(URIUtils.ABOUT_BLANK);

      fBrowserViewer.getControl().setVisible(false);

    } else

      fBrowserViewer.getControl().setVisible(true);