// message_port.h

/*    Copyright 2009 10gen Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    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 Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects
 *    for all of the code used other than as permitted herein. If you modify
 *    file(s) with this exception, you may extend this exception to your
 *    version of the file(s), but you are not obligated to do so. If you do not
 *    wish to do so, delete this exception statement from your version. If you
 *    delete this exception statement from all source files in the program,
 *    then also delete it in the license file.
 */

#pragma once

#include <boost/noncopyable.hpp>
#include <vector>

#include "mongo/config.h"
#include "mongo/util/net/message.h"
#include "mongo/util/net/sock.h"

namespace mongo {

    class MessagingPort;
    class PiggyBackData;

    class AbstractMessagingPort : boost::noncopyable {
    public:
        AbstractMessagingPort() : tag(0), _connectionId(0) {}
        virtual ~AbstractMessagingPort() { }
        virtual void reply(Message& received, Message& response, MSGID responseTo) = 0; // like the reply below, but doesn't rely on received.data still being available
        virtual void reply(Message& received, Message& response) = 0;

        virtual HostAndPort remote() const = 0;
        virtual unsigned remotePort() const = 0;
        virtual SockAddr remoteAddr() const = 0;
        virtual SockAddr localAddr() const = 0;
        
        void setX509SubjectName(const std::string& x509SubjectName) {
            _x509SubjectName = x509SubjectName;
        }

        std::string getX509SubjectName() {
            return _x509SubjectName;
        }

        long long connectionId() const { return _connectionId; }
        void setConnectionId( long long connectionId );

    public:
        // TODO make this private with some helpers

        /* ports can be tagged with various classes.  see closeAllSockets(tag). defaults to 0. */
        unsigned tag;

    private:
        long long _connectionId;
        std::string _x509SubjectName;
    };

    class MessagingPort : public AbstractMessagingPort {
    public:
        MessagingPort(int fd, const SockAddr& remote);

        // in some cases the timeout will actually be 2x this value - eg we do a partial send,
        // then the timeout fires, then we try to send again, then the timeout fires again with
        // no data sent, then we detect that the other side is down
        MessagingPort(double so_timeout = 0,
                      logger::LogSeverity logLevel = logger::LogSeverity::Log() );

        MessagingPort(std::shared_ptr<Socket> socket);

        virtual ~MessagingPort();

        void setSocketTimeout(double timeout);

        void shutdown();

        /* it's assumed if you reuse a message object, that it doesn't cross MessagingPort's.
           also, the Message data will go out of scope on the subsequent recv call.
        */
        bool recv(Message& m);
        void reply(Message& received, Message& response, MSGID responseTo);
        void reply(Message& received, Message& response);
        bool call(Message& toSend, Message& response);

        void say(Message& toSend, int responseTo = 0);

        /**
         * this is used for doing 'async' queries
         * instead of doing call( to , from )
         * you would do
         * say( to )
         * recv( from )
         * Note: if you fail to call recv and someone else uses this port,
         *       horrible things will happen
         */
        bool recv( const Message& sent , Message& response );

        void piggyBack( Message& toSend , int responseTo = 0 );

        unsigned remotePort() const { return psock->remotePort(); }
        virtual HostAndPort remote() const;
        virtual SockAddr remoteAddr() const;
        virtual SockAddr localAddr() const;

        std::shared_ptr<Socket> psock;
                
        void send( const char * data , int len, const char *context ) {
            psock->send( data, len, context );
        }
        void send(const std::vector< std::pair< char *, int > > &data, const char *context) {
            psock->send( data, context );
        }
        bool connect(SockAddr& farEnd) {
            return psock->connect( farEnd );
        }
#ifdef MONGO_CONFIG_SSL
        /**
         * Initiates the TLS/SSL handshake on this MessagingPort.
         * When this function returns, further communication on this
         * MessagingPort will be encrypted.
         * ssl - Pointer to the global SSLManager.
         * remoteHost - The hostname of the remote server.
         */
        bool secure( SSLManagerInterface* ssl, const std::string& remoteHost ) {
            return psock->secure( ssl, remoteHost );
        }
#endif

        bool isStillConnected() {
            return psock->isStillConnected();
        }

        uint64_t getSockCreationMicroSec() const {
            return psock->getSockCreationMicroSec();
        }

    private:
        
        PiggyBackData * piggyBackData;

        // this is the parsed version of remote
        // mutable because its initialized only on call to remote()
        mutable HostAndPort _remoteParsed; 

    public:
        static void closeAllSockets(unsigned tagMask = 0xffffffff);

        friend class PiggyBackData;
    };


} // namespace mongo