/**
 * 
 */
package ie.dcu.apps.ist;

import ie.dcu.apps.ist.actions.ActionManager;
import ie.dcu.apps.ist.actions.HoverMenuManager;
import ie.dcu.apps.ist.actions.OpenAction;
import ie.dcu.apps.ist.actions.OpenRecentAction;

import java.io.File;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Properties;

import org.eclipse.jface.action.Action;
import org.eclipse.jface.action.IAction;
import org.eclipse.jface.action.IMenuListener;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.MenuItem;

/**
 * Recent files menu.
 * 
 * @author Kevin McGuinness
 */
class AppRecentMenu extends HoverMenuManager {
	private final AppRecentFiles history;
	private final EmptyAction empty;
	private final AppWindow window;
	private IAction action;
	
	public AppRecentMenu(AppWindow window, IMenuManager parent) {
		super("Open &Recent");
		
		this.window = window;
		setParent(parent);
		history = AppRecentFiles.getInstance();
		add(empty = new EmptyAction());
		addMenuListener(menuListener);
	
		ActionManager actions = window.getActions();
		if (actions != null) {
			OpenAction openAction = actions.get(OpenAction.class);
			openAction.addPropertyChangeListener(actionListener);
			action = openAction;
		}
		
		try {
			Properties props = window.getProperties();
			String icon = props.getProperty("AppRecentMenu.icon", 
				"file:icons/open-recent.png");
			setImageURL(new URL(icon));
		} catch (MalformedURLException e) {
			// Ignore
		}
	}	
	
	@Override
	public void fill(Menu parent, int index) {
		super.fill(parent, index);
		MenuItem item = getMenuItem();
		if (item != null) {
			item.setEnabled(action.isEnabled());
		}
	}


	private void buildMenu() {
		removeAll();
		
		if (history.empty()) {
			add(empty);
		} else {
			for (File file : history) {
				add(new OpenRecentAction(window.getActions(), file));
			}
		}
		
		update(false);
	}
	
	
	private final class EmptyAction extends Action {
		public EmptyAction() {
			setText("No Recent Files");
			setEnabled(false);
		}
	};
	
	
	private final IMenuListener menuListener = new IMenuListener() {
		public void menuAboutToShow(IMenuManager manager) {
			buildMenu();
		}
	};

	
	private final IPropertyChangeListener actionListener 
		= new IPropertyChangeListener() {

		public void propertyChange(PropertyChangeEvent event) {
			MenuItem item = getMenuItem();
			if (item != null) {
				item.setEnabled(action.isEnabled());
			}
		}
	};
	
}