/*
 * 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.tuscany.sca.policy.logging.jdk;

import java.util.logging.ConsoleHandler;
import java.util.logging.Handler;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.xml.namespace.QName;

import org.apache.tuscany.sca.assembly.xml.Constants;
import org.apache.tuscany.sca.interfacedef.Operation;
import org.apache.tuscany.sca.invocation.Interceptor;
import org.apache.tuscany.sca.invocation.Invoker;
import org.apache.tuscany.sca.invocation.Message;
import org.apache.tuscany.sca.policy.PolicySet;

/**
 * Policy handler to handle PolicySet related to Logging with the QName
 * {http://tuscany.apache.org/xmlns/sca/1.0/impl/java}LoggingPolicy
 *
 * @version $Rev$ $Date$
 */
public class JDKLoggingPolicyInterceptor implements Interceptor {
    public static final String loggingPolicy = "JDKLoggingPolicy";
    public static final QName policySetQName = new QName(Constants.SCA10_TUSCANY_NS, loggingPolicy);
    private Logger logger = null;

    private Invoker next;
    private Operation operation;
    private PolicySet policySet = null;
    private String context;

    public JDKLoggingPolicyInterceptor(String context, Operation operation, PolicySet policySet) {
        super();
        this.operation = operation;
        this.policySet = policySet;
        this.context = context;
        init();
    }

    private void init() {
        if (policySet != null) {
            JDKLoggingPolicy policy = (JDKLoggingPolicy)policySet.getPolicies().get(0);
            logger = Logger.getLogger(policy.getLoggerName());
            logger.setLevel(policy.getLogLevel());
            logger.setUseParentHandlers(policy.isUseParentHandlers());

            boolean found = false;
            for (Handler handler : logger.getHandlers()) {
                if (handler instanceof ConsoleHandler) {
                    found = true;
                    break;
                }
            }

            if (!found) {
                ConsoleHandler consoleHandler = new ConsoleHandler();
                consoleHandler.setLevel(Level.ALL);
                logger.addHandler(consoleHandler);
            }
        }
    }

    public Message invoke(Message msg) {
        if (logger == null) {
            return getNext().invoke(msg);
        }
        Object msgBody = msg.getBody();
        if (msgBody instanceof Object[]) {
            logger.logp(Level.INFO, context, "", "Invoking operation - " + operation.getName());

            StringBuffer sb = new StringBuffer();
            if (msgBody == null) {
                sb.append("");
            } else {
                Object[] args = (Object[])msgBody;
                for (int i = 0; i < args.length; i++) {
                    sb.append(args[i]);
                    if (i != args.length - 1) {
                        sb.append(", ");
                    }
                }
            }

            Object[] logParams = new Object[] {operation.getName(), sb.toString()};
            logger.logp(Level.FINER, context, "", "Invoking operation {0} with arguments {1}", logParams);
        }

        Message responseMsg = null;
        try {
            responseMsg = getNext().invoke(msg);
            return responseMsg;
        } catch (RuntimeException e) {
            logger.logp(Level.SEVERE, context, "", "Exception thrown from operation - " + operation.getName(), e);
            throw e;
        } finally {
            if (responseMsg != null) {
                Object[] logParams = new Object[] {operation.getName(), responseMsg.getBody()};
                logger.logp(Level.INFO, context, "", "Returned from operation - " + operation.getName());
                logger.logp(Level.FINER, context, "", "Returning from operation {0} with return value {1}", logParams);
            }
        }
    }

    public Invoker getNext() {
        return next;
    }

    public void setNext(Invoker next) {
        this.next = next;
    }
}