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.cdm.api.service;

import java.util.ArrayList;

import java.util.List;

import java.util.UUID;

import org.hibernate.NonUniqueResultException;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.dao.DataAccessException;

import org.springframework.dao.IncorrectResultSizeDataAccessException;

import org.springframework.security.access.AccessDeniedException;

import org.springframework.security.authentication.AuthenticationManager;

import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;

import org.springframework.security.authentication.dao.ReflectionSaltSource;

import org.springframework.security.authentication.dao.SaltSource;

import org.springframework.security.authentication.encoding.Md5PasswordEncoder;

import org.springframework.security.authentication.encoding.PasswordEncoder;

import org.springframework.security.core.Authentication;

import org.springframework.security.core.GrantedAuthority;

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

import org.springframework.security.core.userdetails.UserCache;

import org.springframework.security.core.userdetails.UserDetails;

import org.springframework.security.core.userdetails.UsernameNotFoundException;

import org.springframework.security.core.userdetails.cache.NullUserCache;

import org.springframework.stereotype.Service;

import org.springframework.transaction.annotation.Propagation;

import org.springframework.transaction.annotation.Transactional;

import org.springframework.util.Assert;

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

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

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

import eu.etaxonomy.cdm.persistence.dao.common.IGrantedAuthorityDao;

import eu.etaxonomy.cdm.persistence.dao.common.IGroupDao;

import eu.etaxonomy.cdm.persistence.dao.common.IUserDao;

@Service

@Transactional(propagation = Propagation.SUPPORTS, readOnly = true)

public class UserService extends ServiceBase<User,IUserDao> implements IUserService {

	protected IGroupDao groupDao;

	protected IGrantedAuthorityDao grantedAuthorityDao;

	private SaltSource saltSource = new ReflectionSaltSource();

	private PasswordEncoder passwordEncoder = new Md5PasswordEncoder();

	private AuthenticationManager authenticationManager;

	private UserCache userCache = new NullUserCache();

	@Autowired(required = false)

	public void setUserCache(UserCache userCache) {

		Assert.notNull(userCache, "userCache cannot be null");

		this.userCache = userCache;

	}

	@Autowired(required = false)

	public void setPasswordEncoder(PasswordEncoder passwordEncoder) {

		this.passwordEncoder = passwordEncoder;

	}

	@Autowired(required = false)

	public void setSaltSource(SaltSource saltSource) {

		this.saltSource = saltSource;

	}

	@Autowired(required= false)

	public void setAuthenticationManager(AuthenticationManager authenticationManager) {

		this.authenticationManager = authenticationManager;

	}

	@Override

	@Autowired

	protected void setDao(IUserDao dao) {

		this.dao = dao;

	}

	@Autowired

	public void setGroupDao(IGroupDao groupDao) {

		this.groupDao = groupDao;

	}

	@Autowired

	public void setGrantedAuthorityDao(IGrantedAuthorityDao grantedAuthorityDao) {

		this.grantedAuthorityDao = grantedAuthorityDao;

	}

	@Transactional(readOnly=false)

	protected Authentication createNewAuthentication(Authentication currentAuth, String newPassword) {

		UserDetails user = loadUserByUsername(currentAuth.getName());

		UsernamePasswordAuthenticationToken newAuthentication = new UsernamePasswordAuthenticationToken(user, user.getPassword(), user.getAuthorities());

		newAuthentication.setDetails(currentAuth.getDetails());

		return newAuthentication;

	}

	@Transactional(readOnly=false)

	public void changePassword(String oldPassword, String newPassword) {

		Assert.hasText(oldPassword);

		Assert.hasText(newPassword);

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

		if(authentication != null && authentication.getPrincipal() != null && authentication.getPrincipal() instanceof User) {

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

			authenticationManager.authenticate(new UsernamePasswordAuthenticationToken(user.getUsername(), oldPassword));

			Object salt = this.saltSource.getSalt(user);

			String password = passwordEncoder.encodePassword(newPassword, salt);

			((User)user).setPassword(password);

			dao.update((User)user);

			SecurityContextHolder.getContext().setAuthentication(createNewAuthentication(authentication, newPassword));

			userCache.removeUserFromCache(user.getUsername());

		} else {

			throw new AccessDeniedException("Can't change password as no Authentication object found in context for current user.");

		}		

	}

	@Transactional(readOnly=false)

	public void changePasswordForUser(String username, String newPassword) {

		Assert.hasText(username);

		Assert.hasText(newPassword);

		try {

		    User user = dao.findUserByUsername(username);

		    if(user == null) {

				throw new UsernameNotFoundException(username);

			}

            Object salt = this.saltSource.getSalt(user);

			String password = passwordEncoder.encodePassword(newPassword, salt);

			((User)user).setPassword(password);

			dao.update((User)user);

			userCache.removeUserFromCache(user.getUsername());

		} catch(NonUniqueResultException nure) {

			throw new IncorrectResultSizeDataAccessException("More than one user found with name '" + username + "'", 1);

		}

	}

	@Transactional(readOnly=false)

	public void createUser(UserDetails user) {

		Assert.isInstanceOf(User.class, user);

		String rawPassword = user.getPassword();

		Object salt = this.saltSource.getSalt(user);

		String password = passwordEncoder.encodePassword(rawPassword, salt);

		((User)user).setPassword(password);

		dao.save((User)user);

	}

	@Transactional(readOnly=false)

	public void deleteUser(String username) {

		Assert.hasLength(username);

		User user = dao.findUserByUsername(username); 

        if(user != null) {		

		    dao.delete((User)user);

        }

        userCache.removeUserFromCache(username);

	}

	@Transactional(readOnly=false)

	public void updateUser(UserDetails user) {

		Assert.isInstanceOf(User.class, user);

		dao.update((User)user);

		userCache.removeUserFromCache(user.getUsername());

	}

	public boolean userExists(String username) {

		Assert.hasText(username);

		User user = dao.findUserByUsername(username);

		return user != null;

	}

	/**

	 * DO NOT CALL THIS METHOD IN LONG RUNNING SESSIONS OR CONVERSATIONS

	 * A THROWN UsernameNotFoundException WILL RENDER THE CONVERSATION UNUSABLE

	 */

	public UserDetails loadUserByUsername(String username)

			throws UsernameNotFoundException, DataAccessException {

		Assert.hasText(username);

		try {

		    User user = dao.findUserByUsername(username);

		    if(user == null) {

				throw new UsernameNotFoundException(username);

			}

		    return user;

		} catch(NonUniqueResultException nure) {

			throw new IncorrectResultSizeDataAccessException("More than one user found with name '" + username + "'", 1);

		}

	}

	@Transactional(readOnly=false)

	public void addGroupAuthority(String groupName, GrantedAuthority authority) {

		Assert.hasText(groupName);

		Assert.notNull(authority);

		Group group = groupDao.findGroupByName(groupName);

		if(group.getGrantedAuthorities().add(authority)) {

			groupDao.update(group);

		}

	}

	@Transactional(readOnly=false)

	public void addUserToGroup(String username, String groupName) {

		Assert.hasText(username);

		Assert.hasText(groupName);

		Group group = groupDao.findGroupByName(groupName);

		User user = dao.findUserByUsername(username);

		if(group.addMember(user)) {

			groupDao.update(group);

			userCache.removeUserFromCache(user.getUsername());

		}		

	}

	@Transactional(readOnly=false)

	public void createGroup(String groupName, List<GrantedAuthority> authorities) {

		Assert.hasText(groupName);

		Assert.notNull(authorities);

		Group group = new Group();

		group.setName(groupName);

		for(GrantedAuthority authority : authorities) {

			group.getGrantedAuthorities().add(authority);

		}

		groupDao.save(group);

	}

	@Transactional(readOnly=false)

	public void deleteGroup(String groupName) {

		Assert.hasText(groupName);

		Group group = groupDao.findGroupByName(groupName);

		groupDao.delete(group);

	}

	public List<String> findAllGroups() {

		return groupDao.listNames(null,null);

	}

	public List<GrantedAuthority> findGroupAuthorities(String groupName) {

		Assert.hasText(groupName);

		Group group = groupDao.findGroupByName(groupName);

		return new ArrayList<GrantedAuthority>(group.getGrantedAuthorities());

	}

	public List<String> findUsersInGroup(String groupName) {

		Assert.hasText(groupName);

		Group group = groupDao.findGroupByName(groupName);

		List<String> users = groupDao.listMembers(group, null, null);

		return users;

	}

	@Transactional(readOnly=false)

	public void removeGroupAuthority(String groupName,	GrantedAuthority authority) {

		Assert.hasText(groupName);

		Assert.notNull(authority);

		Group group = groupDao.findGroupByName(groupName);

		if(group.getGrantedAuthorities().remove(authority)) {

			groupDao.update(group);

		}

	}

	@Transactional(readOnly=false)

	public void removeUserFromGroup(String username, String groupName) {

		Assert.hasText(username);

		Assert.hasText(groupName);

		Group group = groupDao.findGroupByName(groupName);

		User user = dao.findUserByUsername(username);

		if(group.removeMember(user)) {

			groupDao.update(group);

			userCache.removeUserFromCache(user.getUsername());

		}

	}

	@Transactional(readOnly=false)

	public void renameGroup(String oldName, String newName) {

		Assert.hasText(oldName);

		Assert.hasText(newName);

		Group group = groupDao.findGroupByName(oldName);

		group.setName(newName);

		groupDao.update(group);

	}

	@Transactional(readOnly=false)

	public UUID save(User user) {

		if(user.getId() == 0 || dao.load(user.getUuid()) == null){

			createUser(user);

		}else{

			updateUser(user);

		}

		return user.getUuid(); 

	}

	@Override

	public UUID update(User user) {

		updateUser(user);

		return user.getUuid(); 

	}

	@Transactional(readOnly=false)

	public UUID saveGrantedAuthority(GrantedAuthority grantedAuthority) {

		return grantedAuthorityDao.save((GrantedAuthorityImpl)grantedAuthority);

	}

	@Transactional(readOnly=false)

	public UUID saveGroup(Group group) {

		return groupDao.save(group);

	}

}