/*    This file is part of Peers.    This program is free software: you can redistribute it and/or modify    it under the terms of the GNU General Public License as published by    the Free Software Foundation, either version 3 of the License, or    any later version.    This program is distributed in the hope that it will be useful,    but WITHOUT ANY WARRANTY; without even the implied warranty of    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the    GNU General Public License for more details.    You should have received a copy of the GNU General Public License    along with this program.  If not, see <http://www.gnu.org/licenses/>.        Copyright 2007, 2008 Yohann Martineau */package net.sourceforge.peers.sip.transaction;import java.net.InetAddress;import java.util.Hashtable;import java.util.Timer;import net.sourceforge.peers.sip.RFC3261;import net.sourceforge.peers.sip.Utils;import net.sourceforge.peers.sip.syntaxencoding.SipHeaderFieldName;import net.sourceforge.peers.sip.syntaxencoding.SipHeaderFieldValue;import net.sourceforge.peers.sip.syntaxencoding.SipHeaderParamName;import net.sourceforge.peers.sip.transport.SipMessage;import net.sourceforge.peers.sip.transport.SipRequest;import net.sourceforge.peers.sip.transport.SipResponse;public class TransactionManager {    private static TransactionManager INSTANCE;    public static TransactionManager getInstance() {        if (INSTANCE == null) {            INSTANCE = new TransactionManager();        }        return INSTANCE;    }    protected Timer timer;        private Hashtable<String, ClientTransaction> clientTransactions;    private Hashtable<String, ServerTransaction> serverTransactions;    private TransactionManager() {        clientTransactions = new Hashtable<String, ClientTransaction>();        serverTransactions = new Hashtable<String, ServerTransaction>();        timer = new Timer("Transaction timer");    }        public ClientTransaction createClientTransaction(SipRequest sipRequest,            InetAddress inetAddress, int port, String transport, String pBranchId,            ClientTransactionUser clientTransactionUser) {        String branchId;        if (pBranchId == null || "".equals(pBranchId.trim())                || !pBranchId.startsWith(RFC3261.BRANCHID_MAGIC_COOKIE)) {            branchId = Utils.getInstance().generateBranchId();        } else {            branchId = pBranchId;        }        String method = sipRequest.getMethod();        ClientTransaction clientTransaction;        if (RFC3261.METHOD_INVITE.equals(method)) {            clientTransaction = new InviteClientTransaction(branchId,                    inetAddress, port, transport, sipRequest, clientTransactionUser);        } else {            clientTransaction = new NonInviteClientTransaction(branchId,                    inetAddress, port, transport, sipRequest, clientTransactionUser);        }        clientTransactions.put(getTransactionId(branchId, method),                clientTransaction);        return clientTransaction;    }    public ServerTransaction createServerTransaction(SipResponse sipResponse,            int port, String transport,            ServerTransactionUser serverTransactionUser,            SipRequest sipRequest) {        SipHeaderFieldValue via = Utils.getInstance().getTopVia(sipResponse);        String branchId = via.getParam(new SipHeaderParamName(                RFC3261.PARAM_BRANCH));        String cseq = sipResponse.getSipHeaders().get(                new SipHeaderFieldName(RFC3261.HDR_CSEQ)).toString();        String method = cseq.substring(cseq.lastIndexOf(' ') + 1);        ServerTransaction serverTransaction;        // TODO create server transport user and pass it to server transaction        if (RFC3261.METHOD_INVITE.equals(method)) {            serverTransaction = new InviteServerTransaction(branchId, port,                    transport, sipResponse, serverTransactionUser, sipRequest);            // serverTransaction = new InviteServerTransaction(branchId);        } else {            serverTransaction = new NonInviteServerTransaction(branchId, port,                    transport, method, serverTransactionUser, sipRequest);        }        serverTransactions.put(getTransactionId(branchId, method),                serverTransaction);        return serverTransaction;    }    public ClientTransaction getClientTransaction(SipMessage sipMessage) {        SipHeaderFieldValue via = Utils.getInstance().getTopVia(sipMessage);        String branchId = via.getParam(new SipHeaderParamName(                RFC3261.PARAM_BRANCH));        String cseq = sipMessage.getSipHeaders().get(                new SipHeaderFieldName(RFC3261.HDR_CSEQ)).toString();        String method = cseq.substring(cseq.lastIndexOf(' ') + 1);        return clientTransactions.get(getTransactionId(branchId, method));    }    public ServerTransaction getServerTransaction(SipMessage sipMessage) {        SipHeaderFieldValue via = Utils.getInstance().getTopVia(sipMessage);        String branchId = via.getParam(new SipHeaderParamName(                RFC3261.PARAM_BRANCH));        String method;        if (sipMessage instanceof SipRequest) {            method = ((SipRequest)sipMessage).getMethod();        } else {            String cseq = sipMessage.getSipHeaders().get(                    new SipHeaderFieldName(RFC3261.HDR_CSEQ)).toString();            method = cseq.substring(cseq.lastIndexOf(' ') + 1);        }        if (RFC3261.METHOD_ACK.equals(method)) {            method = RFC3261.METHOD_INVITE;            // TODO if positive response, ACK does not belong to transaction            // retrieve transaction and take responses from transaction            // and check if a positive response has been received            // if it is the case, a new standalone transaction must be created            // for the ACK        }        return serverTransactions.get(getTransactionId(branchId, method));    }    public ServerTransaction getServerTransaction(String branchId, String method) {        return serverTransactions.get(getTransactionId(branchId, method));    }        void removeServerTransaction(String branchId, String method) {        serverTransactions.remove(getTransactionId(branchId, method));    }        private String getTransactionId(String branchId, String method) {        StringBuffer buf = new StringBuffer();        buf.append(branchId);        buf.append(Transaction.ID_SEPARATOR);        buf.append(method);        return buf.toString();    }}