/******************************************************************************* 
 * Copyright (c) 2000, 2005 IBM Corporation and others. 
 * 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.eclipse.org/legal/epl-v10.html 
 * 
 * Contributors: 
 *     IBM Corporation - initial API and implementation 
 *     IBM Corporation - added the following constants
 *******************************************************************************/

package eclipseCon2005.KCH.AuthDemo;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import java.util.StringTokenizer;

import org.eclipse.jface.util.ListenerList;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.PlatformUI;

import eclipseCon2005.KCH.AuthDemo.perspectives.AuthPerspective;
import eclipseCon2005.KCH.AuthDemo.perspectives.NoAuthPerspective;

public class Auth {

	public interface AuthListener {
		public void authChanged();
	}
	
	private ListenerList listenerList = new ListenerList(); 
	
	private AuthEntry currentUser; 
	
	private class AuthEntry {
		String user;

		String password;

		Set activites;
	}

	private static Auth instance;

	private List authTable = new ArrayList();

	private Auth() {
		try {
			BufferedReader reader = new BufferedReader(new InputStreamReader(
					AuthDemoPlugin.getDefault().getBundle().getResource(
							"authtable").openStream()));

			for (String line = reader.readLine(); line != null; line = reader.readLine()) {
				AuthEntry entry = new AuthEntry();
				StringTokenizer tok = new StringTokenizer(line, " ");
				entry.user = tok.nextToken();
				entry.password = tok.nextToken();
				String activities = tok.nextToken();
				entry.activites = new HashSet(Arrays.asList(activities.split(",")));
				
				authTable.add(entry);
			}

		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	public static Auth getInstance() {
		if (instance == null) {
			instance = new Auth();
		}

		return instance;
	}

	public boolean login(String user, String password) {
		for (Iterator i = authTable.iterator(); i.hasNext();) {
			AuthEntry entry = (AuthEntry) i.next();
			if (entry.user.equals(user) && entry.password.equals(password)) {
				IWorkbench workbench = PlatformUI.getWorkbench();
				workbench.getActivitySupport().setEnabledActivityIds(
						entry.activites);
				workbench.getActiveWorkbenchWindow().getActivePage()
						.setPerspective(
								workbench.getPerspectiveRegistry()
										.findPerspectiveWithId(
												AuthPerspective.ID));				
				currentUser = entry;
				notifyListeners();
				return true;
			}
		}

		return false;
	}

	private void notifyListeners() {
		Object [] listeners = listenerList.getListeners();
		for (int k = 0; k < listeners.length; k++) {
			AuthListener l = (AuthListener) listeners[k];
			l.authChanged();
		}
	}

	public void logout() {
		currentUser = null;
		IWorkbench workbench = PlatformUI.getWorkbench();
		workbench.getActivitySupport().setEnabledActivityIds(
				Collections.EMPTY_SET);
		workbench.getActiveWorkbenchWindow().getActivePage().closePerspective(workbench.getPerspectiveRegistry()
				.findPerspectiveWithId(
						AuthPerspective.ID), false, false);
		workbench.getActiveWorkbenchWindow().getActivePage().setPerspective(
				workbench.getPerspectiveRegistry().findPerspectiveWithId(
						NoAuthPerspective.ID));
		notifyListeners();
	}
	
	public String getUserName() {
		return currentUser == null ? null : currentUser.user;
	}
	
	public boolean isManager() {
		return currentUser == null ? false : currentUser.activites.contains("managerActivity");
	}

	public void addAuthListener(AuthListener listener) {
		listenerList.add(listener);
	}
	
	public void removeAuthListener(AuthListener listener) {
		listenerList.remove(listener);
	}

	public Object[] getUserData() {
		ArrayList users = new ArrayList();
		for (Iterator i = authTable.iterator(); i.hasNext();) {
			AuthEntry element = (AuthEntry) i.next();
			users.add(new Object[] {element.user, element.activites.contains("managerActivity") ? "boss" : "monkey"});
		}
		
		return users.toArray();
	}
}