EDIT

// $Id$

/**

* Copyright (C) 2007 EDIT

* European Distributed Institute of Taxonomy 

* http://www.e-taxonomy.eu

* 

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.taxeditor.store;

import java.util.Observable;

import java.util.Set;

import org.apache.log4j.Logger;

import org.eclipse.core.runtime.IProgressMonitor;

import org.eclipse.ui.IMemento;

import org.springframework.security.authentication.BadCredentialsException;

import org.springframework.security.authentication.LockedException;

import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;

import org.springframework.security.core.Authentication;

import org.springframework.security.core.GrantedAuthority;

import org.springframework.security.core.context.SecurityContextHolder;

import eu.etaxonomy.cdm.api.conversation.ConversationHolder;

import eu.etaxonomy.cdm.api.conversation.IConversationEnabled;

import eu.etaxonomy.cdm.model.common.Group;

import eu.etaxonomy.cdm.model.common.User;

import eu.etaxonomy.cdm.persistence.hibernate.CdmDataChangeMap;

import eu.etaxonomy.cdm.persistence.hibernate.permission.CdmAuthority;

import eu.etaxonomy.taxeditor.model.IContextListener;

/**

 * <p>LoginManager class.</p>

 *

 * @author n.hoffmann

 * @created 03.07.2009

 * @version 1.0

 */

public class LoginManager extends Observable implements IConversationEnabled, IContextListener{

	public static final Logger logger = Logger.getLogger(LoginManager.class);

	private ConversationHolder conversation;

	public LoginManager(){

		CdmStore.getContextManager().addContextListener(this);

	}

	/**

	 * <p>authenticate</p>

	 *

	 * @param token a {@link org.springframework.security.authentication.UsernamePasswordAuthenticationToken} object.

	 * @return true if the login attempt was successful even if the authentication has changed or not

	 */

	public boolean authenticate(String username, String password){

		// close all open editors

		if(!StoreUtil.closeAll()){

			return false;

		}

		try{

			getConversationHolder().bind();

			getConversationHolder().commit();

			SecurityContextHolder.clearContext();

			Authentication lastAuthentication = CdmStore.getCurrentAuthentiation();

			UsernamePasswordAuthenticationToken token = new UsernamePasswordAuthenticationToken(username, password); 			

			Authentication authentication = CdmStore.getAuthenticationManager().authenticate(token);

			User user = (User) authentication.getPrincipal();

			/* circumventing problem with hibernate not refreshing the transient collection authorities in this case,

			 * see http://dev.e-taxonomy.eu/trac/ticket/4053 */

			user.initAuthorities(); 

			if(logger.isDebugEnabled()){

				StringBuilder gaText = new StringBuilder();

				String indent = "    ";

				Set<GrantedAuthority> gaSet = user.getGrantedAuthorities();

				_logGrantedAuthotities(gaText, indent, gaSet);

				for(Group gr : user.getGroups()){

					gaText.append(indent).append("gr[").append(gr.hashCode()).append("] \"").append(gr.getName()).append("\" ").append(gr.toString()).append("\n");

					_logGrantedAuthotities(gaText, indent + indent, gr.getGrantedAuthorities());

				}

				logger.debug("User authenticated: " + user.getUsername() + "\n" + gaText.toString());				

			}

			SecurityContextHolder.getContext().setAuthentication(authentication);			

			if(!authentication.equals(lastAuthentication)){

				this.setChanged();

				this.notifyObservers();

			}

			return true;

		}

		catch(BadCredentialsException e){

			StoreUtil.warningDialog("Could not authenticate", this, "Could not authenticate. Reason: Bad Credentials.");

		}

		catch(LockedException e){

			StoreUtil.warningDialog("Could not authenticate", this, "Could not authenticate. Reason: Account is locked.");

		}

		catch(IllegalArgumentException e){

			StoreUtil.warningDialog("Could not authenticate", this, "Could not authenticate. Reason: Username and/or Password empty.");

		}

		return false;

	}

	private void _logGrantedAuthotities(StringBuilder gaText, String indent,

			Set<GrantedAuthority> gaSet) {

		for(GrantedAuthority ga : gaSet){

			gaText.append(indent).append("ga[").append(ga.hashCode()).append("] ").append(ga.toString()).append("\n");

		}

	}

	/**

	 * <p>getAuthenticatedUser</p>

	 *

	 * @return a {@link eu.etaxonomy.cdm.model.common.User} object.

	 */

	public User getAuthenticatedUser(){

		Authentication authentication = SecurityContextHolder.getContext().getAuthentication();

		if(authentication != null 

				&& authentication.getPrincipal() != null 

				&& authentication.getPrincipal() instanceof User){

			return (User)authentication.getPrincipal();

		}

		return null;

	}

	public void logoutAll(){

		SecurityContextHolder.clearContext();

		notifyObservers();		

	}

	/* (non-Javadoc)

	 * @see eu.etaxonomy.cdm.persistence.hibernate.ICdmPostDataChangeObserver#update(eu.etaxonomy.cdm.persistence.hibernate.CdmDataChangeMap)

	 */

	@Override

	public void update(CdmDataChangeMap arg) {}

	/* (non-Javadoc)

	 * @see eu.etaxonomy.cdm.api.conversation.IConversationEnabled#getConversationHolder()

	 */

	@Override

	public ConversationHolder getConversationHolder() {

		if(conversation == null){

			conversation = CdmStore.createConversation();

		}

		return conversation;

	}

	/**

	 * Whether the current user has the role admin

	 * 

	 * @return

	 */

	public boolean isAdmin() {

		// FIXME until we have rights implemented properly we do this

		// by a simple string check. This has to change 

		return "admin".equals(getAuthenticatedUser().getUsername());

	}

	@Override

	public void contextAboutToStop(IMemento memento, IProgressMonitor monitor) {

	}

	@Override

	public void contextStop(IMemento memento, IProgressMonitor monitor) {

	}

	@Override

	public void contextStart(IMemento memento, IProgressMonitor monitor){

		conversation = CdmStore.createConversation();

	}

	@Override

	public void contextRefresh(IProgressMonitor monitor) {

		conversation = CdmStore.createConversation();

	}

	@Override

	public void workbenchShutdown(IMemento memento, IProgressMonitor monitor) {

	}

}