/**
@file	 AsyncTcpClientBase.h
@brief   Contains a base class for creating TCP client connections
@author  Tobias Blomberg
@date	 2003-04-12

This file contains a class that make it easy to create a new TCP connection
to a remote host. See usage instructions in the class definition.

\verbatim
Async - A library for programming event driven applications
Copyright (C) 2003-2022 Tobias Blomberg

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 2 of the License, or
(at your option) 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, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
\endverbatim
*/

#ifndef ASYNC_TCP_CLIENT_BASE_INCLUDED
#define ASYNC_TCP_CLIENT_BASE_INCLUDED


/****************************************************************************
 *
 * System Includes
 *
 ****************************************************************************/

#include <sigc++/sigc++.h>
#include <stdint.h>

#include <string>


/****************************************************************************
 *
 * Project Includes
 *
 ****************************************************************************/

#include <AsyncTcpConnection.h>
#include <AsyncFdWatch.h>
#include <AsyncDnsLookup.h>


/****************************************************************************
 *
 * Local Includes
 *
 ****************************************************************************/



/****************************************************************************
 *
 * Forward declarations
 *
 ****************************************************************************/



/****************************************************************************
 *
 * Namespace
 *
 ****************************************************************************/

namespace Async
{

/****************************************************************************
 *
 * Forward declarations of classes inside of the declared namespace
 *
 ****************************************************************************/

class IpAddress;


/****************************************************************************
 *
 * Defines & typedefs
 *
 ****************************************************************************/



/****************************************************************************
 *
 * Exported Global Variables
 *
 ****************************************************************************/



/****************************************************************************
 *
 * Class definitions
 *
 ****************************************************************************/

/**
@brief	A base class for creating a TCP client connection
@author Tobias Blomberg
@date   2003-04-12

This is a base class for creating TCP client connections. It should notmally
not be used direclt but rather the TcpClient class should be used.
*/
class TcpClientBase : virtual public sigc::trackable
{
  public:
    /**
     * @brief   Constructor
     * @param 	con The connection object associated with this client
     *
     * The object will be constructed and variables will be initialized but
     * no connection will be created until the connect function
     * (see @ref TcpClient::connect) is called.
     * When using this variant of the constructor the connect method which
     * take host and port must be used.
     */
    explicit TcpClientBase(TcpConnection *con);

    /**
     * @brief 	Constructor
     * @param 	con           The connection object associated with this client
     * @param 	remote_host   The hostname of the remote host
     * @param 	remote_port   The port on the remote host to connect to
     *
     * The object will be constructed and variables will be initialized but
     * no connection will be created until the connect function
     * (see @ref TcpClient::connect) is called.
     */
    TcpClientBase(TcpConnection *con, const std::string& remote_host,
                  uint16_t remote_port);

    /**
     * @brief 	Constructor
     * @param 	con           The connection object associated with this client
     * @param 	remote_ip     The IP address of the remote host
     * @param 	remote_port   The port on the remote host to connect to
     *
     * The object will be constructed and variables will be initialized but
     * no connection will be created until the connect function
     * (see @ref TcpClient::connect) is called.
     */
    TcpClientBase(TcpConnection *con, const IpAddress& remote_ip,
                  uint16_t remote_port);

    /**
     * @brief 	Destructor
     */
    virtual ~TcpClientBase(void);

    /**
     * @brief   Move assignmnt operator
     * @param   other The object to move from
     * @return  Returns this object
     */
    virtual TcpClientBase& operator=(TcpClientBase&& other);

    /**
     * @brief   Get the name of the remote host as given to connect()
     * @return  Returns the name of the remote host
     *
     * This function return the name of the remote host as it was given to the
     * connect call. If an IP address was used the text representation of that
     * will be returned.
     */
    std::string remoteHostName(void) const
    {
      if (!dns.label().empty())
      {
        return dns.label();
      }
      return con->remoteHost().toString();
    }

    /**
     * @brief   Bind to the interface having the specified IP address
     * @param   bind_ip The IP address of the interface to bind to
     */
    void setBindIp(const IpAddress& bind_ip);

    /**
     * @brief   Get the bind IP address
     * @return  Returns the bind IP address
     */
    const IpAddress& bindIp(void) const { return bind_ip; }

    /**
     * @brief 	Connect to the remote host
     * @param 	remote_host   The hostname of the remote host
     * @param 	remote_port   The port on the remote host to connect to
     *
     * This function will initiate a connection to the remote host. The
     * connection must not be written to before the connected signal
     * (see @ref TcpClient::connected) has been emitted. If the connection is
     * already established or pending, an assertion will be raised.
     */
    void connect(const std::string &remote_host, uint16_t remote_port);

    /**
     * @brief 	Connect to the remote host
     * @param 	remote_ip     The IP address of the remote host
     * @param 	remote_port   The port on the remote host to connect to
     *
     * This function will initiate a connection to the remote host. The
     * connection must not be written to before the connected signal
     * (see @ref TcpClient::connected) has been emitted. If the connection is
     * already established or pending, an assertion will be raised.
     */
    void connect(const Async::IpAddress& remote_ip, uint16_t remote_port);

    /**
     * @brief 	Connect to the remote host
     *
     * This function will initiate a connection to the remote host. The
     * connection must not be written to before the connected signal
     * (see @ref TcpClient::connected) has been emitted. If the connection is
     * already established or pending, an assertion will be raised.
     */
    void connect(void);

    /**
     * @brief 	Disconnect from the remote host
     *
     * Call this function to disconnect from the remote host. If already
     * disconnected, nothing will be done. The disconnected signal is not
     * emitted when this function is called
     */
    virtual void disconnect(void) = 0;

    /**
     * @brief   Check if the connection is idle
     * @return  Returns \em true if the connection is idle
     *
     * A connection being idle means that it is not connected nor connecting.
     */
    bool isIdle(void) const { return !dns.isPending() && (sock == -1); }

    /**
     * @brief   Return the connection object for this client connection
     * @return  Returns the connection object
     */
    TcpConnection* conObj(void) { return con; }

    /**
     * @brief 	A signal that is emitted when a connection has been established
     */
    sigc::signal<void()>       	      	  connected;

  protected:
    /**
     * @brief   Check if the connection has been fully connected
     * @return  Return \em true if the connection was successful
     *
     * This function return true when the connection has been fully
     * established. It will continue to return true even after disconnection
     * and will be reset at the moment when a new connection attempt is made.
     */
    //virtual bool successfulConnect(void)
    //{
    //  return m_successful_connect;
    //}

    /**
     * @brief   Disconnect from the remote peer
     *
     * This function is used internally to close the connection to the remote
     * peer.
     */
    virtual void closeConnection(void);

    /**
     * @brief   Called when the connection has been established to the server
     *
     * This function may be overridden by inheriting classes to get informed of
     * when a connection has been established. The overriding function should
     * normally call this function.
     */
    virtual void connectionEstablished(void)
    {
      //m_successful_connect = true;
      emitConnected();
    }

    virtual void emitConnected(void)
    {
      connected();
    }

  private:
    TcpConnection *   con;
    DnsLookup         dns;
    int       	      sock;
    FdWatch           wr_watch;
    Async::IpAddress  bind_ip;
    //bool              m_successful_connect  = false;

    void dnsResultsReady(DnsLookup& dns_lookup);
    void connectToRemote(void);
    void connectHandler(FdWatch *watch);

};  /* class TcpClientBase */


} /* namespace */

#endif /* ASYNC_TCP_CLIENT_BASE_INCLUDED */



/*
 * This file has not been truncated
 */

