package org.argeo.cms.ui.forms;
   
   import java.util.Observable;
   import java.util.Observer;
   
   import javax.jcr.Node;
   
   import org.argeo.cms.ui.CmsEditable;
   import org.argeo.cms.ui.util.CmsUiUtils;
  import org.eclipse.swt.SWT;
  import org.eclipse.swt.events.SelectionEvent;
  import org.eclipse.swt.events.SelectionListener;
  import org.eclipse.swt.widgets.Button;
  import org.eclipse.swt.widgets.Composite;
  
  /** Add life cycle management abilities to an editable form page */
  public class FormEditorHeader implements SelectionListener, Observer {
  	private static final long serialVersionUID = 7392898696542484282L;
  
  	// private final Node context;
  	private final CmsEditable cmsEditable;
  	private Button publishBtn;
  
  	// Should we provide here the ability to switch from read only to edition
  	// mode?
  	// private Button editBtn;
  	// private boolean readOnly;
  
  	// TODO add information about the current node status, typically if it is
  	// dirty or not
  
  	private Composite parent;
  	private Composite display;
  	private Object layoutData;
  
  	public FormEditorHeader(Composite parent, int style, Node context,
  			CmsEditable cmsEditable) {
  		this.cmsEditable = cmsEditable;
  		this.parent = parent;
  		// readOnly = SWT.READ_ONLY == (style & SWT.READ_ONLY);
  		// this.context = context;
  		if (this.cmsEditable instanceof Observable)
  			((Observable) this.cmsEditable).addObserver(this);
  		refresh();
  	}
  
  	public void setLayoutData(Object layoutData) {
  		this.layoutData = layoutData;
  		if (display != null && !display.isDisposed())
  			display.setLayoutData(layoutData);
  	}
  
  	protected void refresh() {
  		if (display != null && !display.isDisposed())
  			display.dispose();
  
  		display = new Composite(parent, SWT.NONE);
  		display.setLayoutData(layoutData);
  
  		CmsUiUtils.style(display, FormStyle.header.style());
  		display.setBackgroundMode(SWT.INHERIT_FORCE);
  
  		display.setLayout(CmsUiUtils.noSpaceGridLayout());
  
  		publishBtn = createSimpleBtn(display, getPublishButtonLabel());
  		display.moveAbove(null);
  		parent.layout();
  	}
  
  	private Button createSimpleBtn(Composite parent, String label) {
  		Button button = new Button(parent, SWT.FLAT | SWT.PUSH);
  		button.setText(label);
  		CmsUiUtils.style(button, FormStyle.header.style());
  		button.addSelectionListener(this);
  		return button;
  	}
  
  	private String getPublishButtonLabel() {
  		// Rather check if the current node differs from what has been
  		// previously committed
  		// For the time being, we always reach here, the underlying CmsEditable
  		// is always editing.
  		if (cmsEditable.isEditing())
  			return " Publish ";
  		else
  			return " Edit ";
  	}
  
  	@Override
  	public void widgetSelected(SelectionEvent e) {
  		if (e.getSource() == publishBtn) {
  			// For the time being, the underlying CmsEditable
  			// is always editing when we reach this point
  			if (cmsEditable.isEditing()) {
  				// we always leave the node in a check outed state
  				cmsEditable.stopEditing();
  				cmsEditable.startEditing();
  			} else {
  				cmsEditable.startEditing();
 			}
 		}
 	}
 
 	@Override
 	public void widgetDefaultSelected(SelectionEvent e) {
 	}
 
 	@Override
 	public void update(Observable o, Object arg) {
 		if (o == cmsEditable) {
 			refresh();
 		}
 	}
 }