/*
 * Copyright (C) 2005-2010 Alfresco Software Limited.
 *
 * This file is part of Alfresco
 *
 * Alfresco is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Alfresco is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
 */
package org.alfresco.repo.security.authentication;

import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.Collections;
import java.util.Set;

import net.sf.acegisecurity.Authentication;
import net.sf.acegisecurity.AuthenticationManager;
import net.sf.acegisecurity.UserDetails;
import net.sf.acegisecurity.providers.UsernamePasswordAuthenticationToken;

import org.alfresco.error.AlfrescoRuntimeException;
import org.alfresco.repo.security.authentication.ntlm.NLTMAuthenticator;

public class AuthenticationComponentImpl extends AbstractAuthenticationComponent implements NLTMAuthenticator
{
    private MutableAuthenticationDao authenticationDao;

    AuthenticationManager authenticationManager;

    public AuthenticationComponentImpl()
    {
        super();
    }

    /**
     * IOC
     * 
     * @param authenticationManager
     */
    public void setAuthenticationManager(AuthenticationManager authenticationManager)
    {
        this.authenticationManager = authenticationManager;
    }

    /**
     * IOC
     * 
     * @param authenticationDao
     */
    public void setAuthenticationDao(MutableAuthenticationDao authenticationDao)
    {
        this.authenticationDao = authenticationDao;
    }

    /**
     * Authenticate
     */
    @Override
    protected void authenticateImpl(String userName, char[] password) throws AuthenticationException
    {
        try
        {
            UsernamePasswordAuthenticationToken authentication = new UsernamePasswordAuthenticationToken(userName,
                    new String(password));
            this.authenticationManager.authenticate(authentication);
            setCurrentUser(userName);

        }
        catch (net.sf.acegisecurity.AuthenticationException ae)
        {
            // This is a bit gross, I admit, but when LDAP is
            // configured ae, above, is non-serializable and breaks
            // remote authentication.
            StringWriter sw = new StringWriter();
            PrintWriter out = new PrintWriter(sw);
            out.println(ae.toString());
            ae.printStackTrace(out);
            out.close();
            throw new AuthenticationException(sw.toString());
        }
    }

    /**
     * We actually have an acegi object so override the default method.
     */
    @Override
    protected UserDetails getUserDetails(String userName)
    {
        return this.authenticationDao.loadUserByUsername(userName);
    }

    /**
     * Get the password hash from the DAO
     */
    public String getMD4HashedPassword(String userName)
    {
        return this.authenticationDao.getMD4HashedPassword(userName);
    }

    /**
     * The default is not to support Authentication token base authentication
     */
    public Authentication authenticate(Authentication token) throws AuthenticationException
    {
        throw new AlfrescoRuntimeException("Authentication via token not supported");
    }
    
    /**
     * This implementation supported MD4 password hashes.
     */
    public NTLMMode getNTLMMode()
    {
        return NTLMMode.MD4_PROVIDER;
    }

    @Override
    protected boolean implementationAllowsGuestLogin()
    {
        return true;
    }

    /*
     * (non-Javadoc)
     * @see org.alfresco.repo.security.authentication.AuthenticationComponent#getDefaultAdministratorUserNames()
     */
    @Override
    public Set<String> getDefaultAdministratorUserNames()
    {
        return Collections.singleton(AuthenticationUtil.getAdminUserName());
    }
}