/* 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.ui.preauth;

import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.security.util.ServletUtils;
import org.springframework.util.Assert;

/**
 * Source of the attributes associated with pre-authenticated authentication request. The attributes
 * can be supplied in the request header. The keys for values to be extracted must be specified as a
 * <tt>keys</tt> property.
 * 
 * @author Valery Tydykov
 * 
 */
public class HeaderAttributesSource implements AttributesSource, InitializingBean {

    /**
     * Logger for this class and subclasses
     */
    protected final Log logger = LogFactory.getLog(this.getClass());

    // keys for values to be extracted
    private List keys;

    /**
     * @return the keys
     */
    public List getKeys() {
        return this.keys;
    }

    /**
     * @param keys the keys to set
     */
    public void setKeys(List keys) {
        this.keys = keys;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.springframework.security.ui.preauth.AttributesSource#obtainAttributes(javax.servlet.http.HttpServletRequest)
     */
    public Map obtainAttributes(HttpServletRequest request) {
        Map attributes = ServletUtils.extractHeaderValues(request, this.getKeys());

        if (this.logger.isDebugEnabled()) {
            this.logger.debug("Obtained attributes=[" + attributes + "] from header");
        }

        return attributes;
    }

    public void afterPropertiesSet() throws Exception {
        Assert.notNull(this.keys, "keys must be not null");
    }
}
