/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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.cxf.ws.policy;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;

import org.apache.cxf.Bus;
import org.apache.cxf.common.logging.LogUtils;
import org.apache.cxf.endpoint.Endpoint;
import org.apache.cxf.interceptor.Interceptor;
import org.apache.cxf.message.Exchange;
import org.apache.cxf.message.Message;
import org.apache.cxf.message.MessageUtils;
import org.apache.cxf.phase.Phase;
import org.apache.cxf.service.model.BindingOperationInfo;
import org.apache.cxf.service.model.EndpointInfo;
import org.apache.cxf.transport.Conduit;
import org.apache.cxf.transport.Destination;
import org.apache.neethi.Assertion;
import org.apache.neethi.Policy;

/**
 * 
 */
public class PolicyInInterceptor extends AbstractPolicyInterceptor {
    public static final PolicyInInterceptor INSTANCE = new PolicyInInterceptor();
    
    private static final Logger LOG = LogUtils.getL7dLogger(PolicyInInterceptor.class);
    
    public PolicyInInterceptor() {
        super(PolicyConstants.POLICY_IN_INTERCEPTOR_ID, Phase.RECEIVE);
    }
    
    protected void handle(Message msg) {
        Exchange exchange = msg.getExchange();
        Bus bus = exchange.get(Bus.class);
        Endpoint e = exchange.get(Endpoint.class);
        if (null == e) {
            LOG.fine("No endpoint.");
            return;
        }
        EndpointInfo ei = e.getEndpointInfo();
        
        PolicyEngine pe = bus.getExtension(PolicyEngine.class);
        if (null == pe) {
            return;
        }

        List<Interceptor<? extends Message>> interceptors = new ArrayList<Interceptor<? extends Message>>();
        Collection<Assertion> assertions = new ArrayList<Assertion>();
        
        // 1. Check overridden policy
        Policy p = (Policy)msg.getContextualProperty(PolicyConstants.POLICY_OVERRIDE);
        if (p != null) {
            EndpointPolicyImpl endpi = new EndpointPolicyImpl(p);
            EffectivePolicyImpl effectivePolicy = new EffectivePolicyImpl();
            effectivePolicy.initialise(endpi, (PolicyEngineImpl)pe, true, msg);
            msg.put(EffectivePolicy.class, effectivePolicy);
            PolicyUtils.logPolicy(LOG, Level.FINEST, "Using effective policy: ", 
                                  effectivePolicy.getPolicy());
            
            interceptors.addAll(effectivePolicy.getInterceptors());
            assertions.addAll(effectivePolicy.getChosenAlternative());
        } else if (MessageUtils.isRequestor(msg)) {
            // 2. Process client policy
            BindingOperationInfo boi = exchange.get(BindingOperationInfo.class);
            if (boi == null) {
                Conduit conduit = exchange.getConduit(msg);
                EndpointPolicy ep = pe.getClientEndpointPolicy(ei, conduit, msg);
                if (ep != null) {
                    interceptors.addAll(ep.getInterceptors(msg));
                    assertions.addAll(ep.getVocabulary(msg));
                }
            } else {
                // We do not know the underlying message type yet - so we pre-emptively add interceptors 
                // that can deal with any resposes or faults returned to this client endpoint.
                
                EffectivePolicy ep = pe.getEffectiveClientResponsePolicy(ei, boi, msg);
                if (ep != null) {
                    interceptors.addAll(ep.getInterceptors());
                    // insert assertions of endpoint's vocabulary into message
                    if (ep.getPolicy() != null) {
                        msg.put(AssertionInfoMap.class, new AssertionInfoMap(ep.getPolicy()));
                        msg.getInterceptorChain().add(PolicyVerificationInInterceptor.INSTANCE);
                    }
                }
            }
        } else {            
            // 3. Process server policy
            Destination destination = exchange.getDestination();
            
            // We do not know the underlying message type yet - so we pre-emptively add interceptors 
            // that can deal with any messages to this endpoint
            
            EndpointPolicy ep = pe.getServerEndpointPolicy(ei, destination, msg);
            if (ep != null) {
                interceptors.addAll(ep.getInterceptors(msg));
                assertions.addAll(ep.getVocabulary(msg));
            }
        }
        
        // add interceptors into message chain
        for (Interceptor<? extends Message> i : interceptors) {
            msg.getInterceptorChain().add(i);
        }
        
        // Insert assertions of endpoint's vocabulary into message
        if (!assertions.isEmpty()) {
            msg.put(AssertionInfoMap.class, new AssertionInfoMap(assertions));
            msg.getInterceptorChain().add(PolicyVerificationInInterceptor.INSTANCE);
        }
        
    }
}