/* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.security.authentication;

import org.springframework.beans.factory.InitializingBean;
import org.springframework.context.MessageSource;
import org.springframework.context.MessageSourceAware;
import org.springframework.context.support.MessageSourceAccessor;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.AuthenticationException;
import org.springframework.security.core.SpringSecurityMessageSource;
import org.springframework.util.Assert;


/**
 * An {@link AuthenticationProvider} implementation that validates {@link AnonymousAuthenticationToken}s.
 * <p>
 * To be successfully validated, the {@link AnonymousAuthenticationToken#getKeyHash()} must match this class'
 * {@link #getKey()}.
 *
 * @author Ben Alex
 */
public class AnonymousAuthenticationProvider implements AuthenticationProvider, InitializingBean, MessageSourceAware {

    //~ Instance fields ================================================================================================

    protected MessageSourceAccessor messages = SpringSecurityMessageSource.getAccessor();
    private String key;

    /**
     *
     * @deprecated Use constructor injection
     */
    @Deprecated
    public AnonymousAuthenticationProvider() {
    }

    public AnonymousAuthenticationProvider(String key) {
        this.key = key;
    }

    //~ Methods ========================================================================================================

    public void afterPropertiesSet() throws Exception {
        Assert.hasLength(key, "A Key is required");
    }

    public Authentication authenticate(Authentication authentication)
        throws AuthenticationException {
        if (!supports(authentication.getClass())) {
            return null;
        }

        if (this.key.hashCode() != ((AnonymousAuthenticationToken) authentication).getKeyHash()) {
            throw new BadCredentialsException(messages.getMessage("AnonymousAuthenticationProvider.incorrectKey",
                    "The presented AnonymousAuthenticationToken does not contain the expected key"));
        }

        return authentication;
    }

    public String getKey() {
        return key;
    }

    /**
     *
     * @deprecated Use constructor injection
     */
    @Deprecated
    public void setKey(String key) {
        this.key = key;
    }

    public void setMessageSource(MessageSource messageSource) {
        Assert.notNull(messageSource, "messageSource cannot be null");
        this.messages = new MessageSourceAccessor(messageSource);
    }

    public boolean supports(Class<?> authentication) {
        return (AnonymousAuthenticationToken.class.isAssignableFrom(authentication));
    }
}
