package org.lsst.ccs.plugin.jas3.trending.timeselection;
   
   import java.awt.BorderLayout;
   import java.awt.Component;
   import java.awt.event.ActionEvent;
   import java.awt.event.ActionListener;
   import java.util.List;
   import javax.swing.DefaultComboBoxModel;
   import javax.swing.JComboBox;
  import javax.swing.JList;
  import javax.swing.JPanel;
  import javax.swing.JSeparator;
  import javax.swing.ListCellRenderer;
  import org.freehep.application.studio.Studio;
  
  /**
   * GUI for selecting time window for trending plots.
   * Provides a way to select time window from a list of presets and to open custom time window
   * creation and preset management dialogs, as well as access the currently selected time window.
   *
   * @author onoprien
   */
  final public class TimeSelectionComboBox extends JComboBox {
      
  // -- Private parts : ----------------------------------------------------------
         
      static private final String CUSTOM_BUTTON = "Choose...";
      static private final String PRESETS_BUTTON = "Presets...";
      static private final String DEFAULT_NAME = "custom";
      static private final int MAX_PRESETS = 10; // Maximum number of presets to include in drop-down list
      
      private final PresetList timeWindowList;
      private volatile TimeSelection selection;
      
  
  // -- Construction and initialization : ----------------------------------------
      
      public TimeSelectionComboBox(Studio application) {
          
          timeWindowList = new PresetList(application);
          
          setRenderer(new Renderer(getRenderer()));
          setMaximumRowCount(MAX_PRESETS + 5);
          
          Model model = new Model(timeWindowList);
          setModel(model);
          setSelectedIndex(1);
          selection = model.getSelectedItem();
          
          addActionListener(new ActionListener() {
              public void actionPerformed(ActionEvent e) {
                  TimeSelection ts = myModel().getSelectedItem();
                  
                  switch (ts.name) {
                      
                      case CUSTOM_BUTTON: // custom time window has been entered
                          
                          ts = TimeSelectionPanel.editTimeWindow(TimeSelectionComboBox.this, null);
                          if (ts == null) {
                              setSelectedItem(selection);
                          } else {
                              if (ts.name.isEmpty()) {
                                  ts.name = DEFAULT_NAME;
                                  if (DEFAULT_NAME.equals(selection.name)) {
                                      myModel().removeElementAt(4);
                                  }
                                  myModel().insertElementAt(ts, 4);
                                  setSelectedIndex(4);
                              } else {
                                  timeWindowList.insert(ts);
                                  Model model = new Model(timeWindowList);
                                  model.setSelectedItem(ts);
                                  setModel(model);
                              }
                              selection = ts;
                          }
                          break;
                          
                      case PRESETS_BUTTON: // one of the presets has been selected through presets dialog
                          
                          ts = PresetsDialog.managePresets(TimeSelectionComboBox.this, timeWindowList);
                          if (ts == null) ts = selection;
                          ts.touch();
                          Model model = new Model(timeWindowList);
                          int index = model.getIndexOf(ts);
                          if (index == -1) index = 1;
                          selection = model.getElementAt(index);
                          model.setSelectedItem(selection);
                          setModel(model);
                          break;
                          
                      default: // one of the presets has been selected from drop-down list
                          
                          if (!DEFAULT_NAME.equals(ts.name)) {
                              ts.touch();
                              if (DEFAULT_NAME.equals(selection.name)) {
                                  myModel().removeElementAt(4);
                              }
                          }
                         selection = ts;
                         
                 }
             }
         });
         
     }
     
 // -- Getters : ----------------------------------------------------------------
     
     private Model myModel() {
         return (Model) super.getModel();
     }
     
     /** Returns currently selected time window. */
     public TimeSelection getSelectedTimeWindow() {
         return selection;
     }
     
     /** 
      * Returns <tt>TimeSelectionList</tt> instance that maintains a list of time 
      * window presets currently known to the application.
      */
     public PresetList getPresetList() {
         return timeWindowList;
     }
     
 // -- Custom renderer : --------------------------------------------------------
     
     private class Renderer implements ListCellRenderer {
 
         private final ListCellRenderer horse;
         private final JPanel separatorPanel = new JPanel(new BorderLayout());
         private final JSeparator separator = new JSeparator();
 
         Renderer(ListCellRenderer renderer) {
             horse = renderer;
         }
 
         @Override
         public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
             Component comp = horse.getListCellRendererComponent(list, ((TimeSelection)value).name, index, isSelected, cellHasFocus);
             if (index == 0 || index == 3) {
                 separatorPanel.removeAll();
                 separatorPanel.add(comp, BorderLayout.CENTER);
                 separatorPanel.add(separator, BorderLayout.SOUTH);
                 comp = separatorPanel;
             } else if (index > 4 && index == TimeSelectionComboBox.this.getItemCount()-1) {
                 separatorPanel.removeAll();
                 separatorPanel.add(comp, BorderLayout.CENTER);
                 separatorPanel.add(separator, BorderLayout.NORTH);
                 comp = separatorPanel;
             }
             return comp;
         }
 
     }
     
 // -- Custom model : -----------------------------------------------------------
     
     private class Model extends DefaultComboBoxModel<TimeSelection> {
         
         Model(PresetList tsList) {
 
         // Add element for launching time range construction dialog :
             
             addElement(new TimeSelection(CUSTOM_BUTTON, "", "", false));
 
         // Add standard ranges :
             
             TimeSelection selectedItem = new TimeSelection("Last Hour", "now-3600", "now", false);
             addElement(selectedItem);
             addElement(new TimeSelection("Last 6 Hours", "now-21600", "now", false));
             addElement(new TimeSelection("Last 24 Hours", "now-86400", "now", false));
 
         // Add custom ranges :
             
             List<TimeSelection> customRanges = tsList.getRecent(MAX_PRESETS);
 
             for (TimeSelection ts : customRanges) {
                 addElement(ts);
             }
 
         // Add element for launching time range presets dialog :
             
             addElement(new TimeSelection(PRESETS_BUTTON, "", "", false));
 
         // Set default selection :
             
             setSelectedItem(selectedItem);
         }
     
         @Override
         public TimeSelection getSelectedItem() {
             return (TimeSelection) super.getSelectedItem();
         }
         
     }
     
 }