/*
 *
 * 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.
 *
 */
using System;
using System.Text;
using log4net;
using Qpid.Client.Protocol;
using Qpid.Client.State;
using Qpid.Framing;

namespace Qpid.Client.Handler
{
    public class ConnectionStartMethodHandler : IStateAwareMethodListener
    {
        private static readonly ILog _log = LogManager.GetLogger(typeof(ConnectionStartMethodHandler));

        public void MethodReceived(AMQStateManager stateManager, AMQMethodEvent evt)
        {
            ConnectionStartBody body = (ConnectionStartBody) evt.Method;
            AMQProtocolSession ps = evt.ProtocolSession;
            string username = ps.Username;
            string password = ps.Password;

            try
            {
                if (body.Mechanisms == null)
                {
                    throw new AMQException("mechanism not specified in ConnectionStart method frame");
                }
                string allMechanisms = Encoding.ASCII.GetString(body.Mechanisms);
                string[] mechanisms = allMechanisms.Split(' ');
                string selectedMechanism = null;
                foreach (string mechanism in mechanisms)
                {
                    if (mechanism.Equals("PLAIN"))
                    {
                        selectedMechanism = mechanism;
                        break;
                    }
                }
        
                if (selectedMechanism == null)
                {
                    throw new AMQException("No supported security mechanism found, passed: " + mechanisms);
                }

                // we always write out a null authzid which we don't currently use
                byte[] plainData = new byte[1 + ps.Username.Length + 1 + ps.Password.Length];
                Encoding.UTF8.GetBytes(username, 0, username.Length, plainData, 1);
                Encoding.UTF8.GetBytes(password, 0, password.Length, plainData, username.Length + 2);
                if (body.Locales == null)
                {
                    throw new AMQException("Locales is not defined in Connection Start method");
                }
                string allLocales = Encoding.ASCII.GetString(body.Locales);
                string[] locales = allLocales.Split(' ');
                string selectedLocale;
                if (locales != null && locales.Length > 0)
                {
                    selectedLocale = locales[0];
                }
                else
                {
                    throw new AMQException("No locales sent from server, passed: " + locales);
                }

                stateManager.ChangeState(AMQState.CONNECTION_NOT_TUNED);
                FieldTable clientProperties = new FieldTable();
                clientProperties["product"] = "Qpid.NET";
                clientProperties["version"] = "1.0";
                clientProperties["platform"] = GetFullSystemInfo();
                AMQFrame frame = ConnectionStartOkBody.CreateAMQFrame(evt.ChannelId, clientProperties, selectedMechanism,
                                                                      plainData, selectedLocale);
                ps.WriteFrame(frame);
            }
            catch (Exception e)
            {
                throw new AMQException(_log, "Unable to decode data: " + e, e);
            }
        }

        private string GetFullSystemInfo()
        {
            /*StringBuffer fullSystemInfo = new StringBuffer();
            fullSystemInfo.append(System.getProperty("java.runtime.name"));
            fullSystemInfo.append(", " + System.getProperty("java.runtime.version"));
            fullSystemInfo.append(", " + System.getProperty("java.vendor"));
            fullSystemInfo.append(", " + System.getProperty("os.arch"));
            fullSystemInfo.append(", " + System.getProperty("os.name"));
            fullSystemInfo.append(", " + System.getProperty("os.version"));
            fullSystemInfo.append(", " + System.getProperty("sun.os.patch.level"));*/
            // TODO: add in details here
            return ".NET 1.1 Client";
        }
    }
}
