#ifndef ASCON_H
#define ASCON_H

#include "sics.h"
#include "errormsg.h"

/** \file
 * \brief Asynchronous connection handling for devices controlled over tcp-ip
 * connections. Interface for higher level modules.
 */
 
/** \brief the asynchronous connection
 */
typedef struct Ascon Ascon;

/** \brief the possible results of AsconTask
 */
typedef enum {
  AsconOffline,
  AsconUnconnected,
  AsconPending,
  AsconReady,
  AsconFailure
} AsconStatus;

/** \brief make a new asynchronous connection
 *  \param con the SICS connection
 *  \param argc number of arguments
 *  \param argv the arguments. argv[0] must be the protocol name, the other arguments
 *     are protocol specific, but argv[1] is usually host::port
 *  \return the created connection or NULL on failure
 */
Ascon *AsconMake(SConnection *con, int argc, char *argv[]);

/** \brief kill function
 *  \param a the connection to be killed
 */
void AsconKill(Ascon *a);

/** \brief the task handler. To be called repeatedly.
 *  \param a the connection
 *  \return the state of the connection
 */ 
AsconStatus AsconTask(Ascon *a);

/** \brief write to the connection. allowed only when the state is AsconReady
 *  \param a the connection
 *  \param command the command to be sent
 *  \param noResponse 0 normally, 1 if no reponse is expected
 *  \return 1 on success, 0 when not ready
 */
int AsconWrite(Ascon *a, char *command, int noResponse);

/** \brief read from the connection. allowed only when a response is available
 *  \param a the connection
 *  \return the response when a response is ready
 *      NULL when the command has not completed and the response is not yet finished
 *      "" when the command has completed, but no response was expected.
 *      The result is only valid until the next call to other AsconXxx functions
 *      and has to be duplicated if needed later.
 */
char *AsconRead(Ascon *a);

/** \brief get the connections error list
 *  \return the error list
 */
ErrMsg *AsconGetErrList(Ascon *a);

/** \brief a helper function
 *  \param argc the number of args
 *  \param argv the args to be concatenated
 *  \result a allocated string containing the concatenated arguments
 *     the args are properly quoted to be used as tcl proc arguments
 */
char *ConcatArgs(int argc, char *argv[]);

/** \brief function for dealing with times with musec resolution
 *  \return absolute time as double value
 */
double DoubleTime(void);

#endif