/*
 * Copyright 2001-2004 The Apache Software Foundation.
 * 
 * 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.apache.ws.secpolicy.builders;

import java.util.Iterator;
import java.util.List;

import javax.xml.namespace.QName;

import org.apache.axiom.om.OMElement;
import org.apache.neethi.Assertion;
import org.apache.neethi.AssertionBuilderFactory;
import org.apache.neethi.Policy;
import org.apache.neethi.PolicyEngine;
import org.apache.neethi.builders.AssertionBuilder;
import org.apache.ws.secpolicy.Constants;
import org.apache.ws.secpolicy.model.ProtectionToken;
import org.apache.ws.secpolicy.model.Token;

public class ProtectionTokenBuilder implements AssertionBuilder {

    public Assertion build(OMElement element, AssertionBuilderFactory factory) throws IllegalArgumentException {
        ProtectionToken protectionToken = new ProtectionToken();
        
        Policy policy = PolicyEngine.getPolicy(element.getFirstElement());
        policy = (Policy) policy.normalize(false);
        
        for (Iterator iterator = policy.getAlternatives(); iterator.hasNext();) {
            processAlternative((List) iterator.next(), protectionToken);
            break; // since there should be only one alternative ..
        }
        
        return protectionToken;
    }
        
    public QName[] getKnownElements() {
        return new QName[] {Constants.PROTECTION_TOKEN};
    }

    private void processAlternative(List assertions, ProtectionToken parent) {
        Object token = assertions.get(0);
        
        if (token instanceof Token) {
            parent.setToken((Token) token);
        }
    }
}