/****************************************************************************
 * This file is part of the project AqHome.
 * AqHome (c) by 2025 Martin Preuss, all rights reserved.
 *
 * The license for this file can be found in the file COPYING which you
 * should have received along with this file.
 ****************************************************************************/

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include "./msgwriter_p.h"
#include <aqhome/events2/fdobject.h>

#include <gwenhywfar/inherit.h>
#include <gwenhywfar/debug.h>
#include <gwenhywfar/endianfns.h>

#include <sys/socket.h>


#define AQH_MSGWRITER_FLAGS_MSGSTARTED 0x80000000



GWEN_INHERIT(AQH_OBJECT, AQH_MSG_WRITER)



/* ------------------------------------------------------------------------------------------------
 * forward declarations
 * ------------------------------------------------------------------------------------------------
 */

static void GWENHYWFAR_CB _freeData(void *bp, void *p);
static int _handleSignal(AQH_OBJECT *o, uint32_t slotId, AQH_OBJECT *senderObject, int param1, void *param2);
static int _handleSocketReady(AQH_OBJECT *o, AQH_OBJECT *fdObject);
static int _startMsg(AQH_MSG_WRITER *xo, AQH_OBJECT *fdObject);
static void _endMsg(AQH_MSG_WRITER *xo, AQH_OBJECT *fdObject);
static void _resetBuffer(AQH_OBJECT *o);
static void _cbEnable(AQH_OBJECT *o);
static void _cbDisable(AQH_OBJECT *o);



/* ------------------------------------------------------------------------------------------------
 * implementation
 * ------------------------------------------------------------------------------------------------
 */

AQH_OBJECT *AQH_MsgWriter_new(AQH_EVENT_LOOP *eventLoop, AQH_OBJECT *fdObject)
{
  AQH_OBJECT *o;
  AQH_MSG_WRITER *xo;

  o=AQH_Object_new(eventLoop);
  GWEN_NEW_OBJECT(AQH_MSG_WRITER, xo);
  GWEN_INHERIT_SETDATA(AQH_OBJECT, AQH_MSG_WRITER, o, xo, _freeData);

  AQH_Object_SetSignalHandlerFn(o, _handleSignal);
  AQH_Object_SetEnableFn(o, _cbEnable);
  AQH_Object_SetDisableFn(o, _cbDisable);

  if (fdObject) {
    xo->fdObject=fdObject;
    AQH_Object_AddLink(xo->fdObject, AQH_FDOBJECT_SIGNAL_ISREADY, AQH_MSGWRITER_SLOT_SOCKETREADY, o);
  }

  return o;
}



void GWENHYWFAR_CB _freeData(GWEN_UNUSED void *bp, void *p)
{
  AQH_MSG_WRITER *xo;

  xo=(AQH_MSG_WRITER*) p;
  if (xo->fdObject) {
    AQH_Object_Disable(xo->fdObject);
    AQH_Object_free(xo->fdObject);
    xo->fdObject=NULL;
  }
  GWEN_FREE_OBJECT(xo);
}



void AQH_MsgWriter_SendMsg(AQH_OBJECT *o, const uint8_t *ptr, int len)
{
  if (o) {
    AQH_MSG_WRITER *xo;

    xo=GWEN_INHERIT_GETDATA(AQH_OBJECT, AQH_MSG_WRITER, o);
    if (xo) {
      _resetBuffer(o);
      if (ptr && len) {
        xo->msgBufPtr=ptr;
        xo->msgBufLen=len;
      }
      xo->bytesLeft=xo->msgBufLen;
      xo->currentPtr=xo->msgBufPtr;
      xo->flags&=~AQH_MSGWRITER_FLAGS_MSGSTARTED;
    }
  }
}



int _handleSignal(AQH_OBJECT *o,
                  uint32_t slotId,
                  GWEN_UNUSED AQH_OBJECT *senderObject,
                  GWEN_UNUSED int param1,
                  GWEN_UNUSED void *param2)
{
  switch(slotId) {
  case AQH_MSGWRITER_SLOT_SOCKETREADY: return _handleSocketReady(o, senderObject);
  default:
    break;
  }

  return 0; /* not handled */
}



int _handleSocketReady(AQH_OBJECT *o, AQH_OBJECT *fdObject)
{
  AQH_MSG_WRITER *xo;

  DBG_DEBUG(AQH_LOGDOMAIN, "Socket ready");
  xo=GWEN_INHERIT_GETDATA(AQH_OBJECT, AQH_MSG_WRITER, o);
  if (xo) {
    int rv;

    if (xo->bytesLeft) {
      if (!(xo->flags & AQH_MSGWRITER_FLAGS_MSGSTARTED)) {
        DBG_INFO(NULL, "Starting message");
        rv=_startMsg(xo, fdObject);
        if (rv<0) {
          if (rv==GWEN_ERROR_TRY_AGAIN) {
            /* line is busy */
          }
          else {
            _endMsg(xo, fdObject);
            AQH_Object_EmitSignal(o, AQH_MSG_WRITER_SIGNAL_ERROR, rv, NULL);
          }
          return 1;
        }
      }

      do {
        rv=AQH_FdObject_Write(fdObject, xo->currentPtr, xo->bytesLeft);
        if (rv>0) {
          xo->currentPtr+=rv;
          xo->bytesLeft-=rv;
        }
      } while (rv>0 && xo->bytesLeft>0);
      if (rv<0 && rv!=GWEN_ERROR_TRY_AGAIN) {
        _endMsg(xo, fdObject);
        AQH_Object_EmitSignal(o, AQH_MSG_WRITER_SIGNAL_ERROR, rv, NULL);
      }
      else {
        if (xo->bytesLeft==0) {
          int msgLen;
          const uint8_t *msgPtr;

          _endMsg(xo, fdObject);
          DBG_INFO(NULL, "Ended message");
          msgPtr=xo->msgBufPtr;
          msgLen=xo->msgBufLen;
          _resetBuffer(o);
          rv=AQH_Object_EmitSignal(o, AQH_MSG_WRITER_SIGNAL_MSGSENT, msgLen, (void*) msgPtr);
          if (rv==0) {
            DBG_ERROR(AQH_LOGDOMAIN, "Sent message ignored");
          }
        }
      }
    }
    return 1;
  }
  return 0;
}



int _startMsg(AQH_MSG_WRITER *xo, AQH_OBJECT *fdObject)
{
  int rv;

  rv=AQH_FdObject_StartMsg(fdObject);
  if (rv<0) {
    /* line is busy */
    return rv;
  }
  xo->flags|=AQH_MSGWRITER_FLAGS_MSGSTARTED;
  return 0;
}



void _endMsg(AQH_MSG_WRITER *xo, AQH_OBJECT *fdObject)
{
  xo->flags&=~AQH_MSGWRITER_FLAGS_MSGSTARTED;
  AQH_FdObject_EndMsg(fdObject);
}



void _resetBuffer(AQH_OBJECT *o)
{
  AQH_MSG_WRITER *xo;

  xo=GWEN_INHERIT_GETDATA(AQH_OBJECT, AQH_MSG_WRITER, o);
  if (xo) {
    xo->msgBufPtr=NULL;
    xo->msgBufLen=0;
    xo->currentPtr=NULL;
    xo->bytesLeft=0;
  }
}



void _cbEnable(AQH_OBJECT *o)
{
  if (o) {
    AQH_MSG_WRITER *xo;

    xo=GWEN_INHERIT_GETDATA(AQH_OBJECT, AQH_MSG_WRITER, o);
    if (xo && xo->fdObject)
      AQH_Object_Enable(xo->fdObject);
  }
}



void _cbDisable(AQH_OBJECT *o)
{
  if (o) {
    AQH_MSG_WRITER *xo;

    xo=GWEN_INHERIT_GETDATA(AQH_OBJECT, AQH_MSG_WRITER, o);
    if (xo && xo->fdObject)
      AQH_Object_Disable(xo->fdObject);
  }
}