/****************************************************************************
 * This file is part of the project AqHome.
 * AqHome (c) by 2023 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 "aqhome/mqtt/endpoint_mqttc_p.h"
#include "aqhome/mqtt/msg_mqtt.h"

#include <gwenhywfar/endpoint_tcpc.h>
#include <gwenhywfar/debug.h>



#define GWEN_MSG_ENDPOINT_MQTTC_NAME    "mqttc"
#define GWEN_ENDPOINT_MQTTC_BUFFERSIZE  1024


GWEN_INHERIT(GWEN_MSG_ENDPOINT, AQH_ENDPOINT_MQTTC)


static void GWENHYWFAR_CB _freeData(void *bp, void *p);
static int _isMsgComplete(GWEN_MSG_ENDPOINT *ep, GWEN_MSG *msg);
static int _calcAndSetPayloadSizeAndOffset(GWEN_MSG *msg);




GWEN_MSG_ENDPOINT *AQH_MqttClientEndpoint_new(const char *host, int port, const char *name, int groupId)
{
  GWEN_MSG_ENDPOINT *ep;
  AQH_ENDPOINT_MQTTC *xep;

  ep=GWEN_TcpcEndpoint_new(host, port, name?name:GWEN_MSG_ENDPOINT_MQTTC_NAME, groupId);
  if (ep==NULL) {
    DBG_INFO(AQH_LOGDOMAIN, "here");
    return NULL;
  }
  GWEN_NEW_OBJECT(AQH_ENDPOINT_MQTTC, xep);
  GWEN_INHERIT_SETDATA(GWEN_MSG_ENDPOINT, AQH_ENDPOINT_MQTTC, ep, xep, _freeData);

  GWEN_MsgEndpoint_SetDefaultBufferSize(ep, GWEN_ENDPOINT_MQTTC_BUFFERSIZE);
  GWEN_MsgEndpoint_SetIsMsgCompleteFn(ep, _isMsgComplete);

  return ep;
}



void _freeData(void *bp, void *p)
{
  AQH_ENDPOINT_MQTTC *xep;

  xep=(AQH_ENDPOINT_MQTTC*) p;
  GWEN_FREE_OBJECT(xep);
}



int _isMsgComplete(GWEN_UNUSED GWEN_MSG_ENDPOINT *ep, GWEN_MSG *msg)
{
  int rv;

  if (!(GWEN_Msg_GetFlags(msg) & GWEN_MSG_FLAGS_PAYLOADINFO_SET)) {
    rv=_calcAndSetPayloadSizeAndOffset(msg);
    if (rv<0) {
      DBG_INFO(AQH_LOGDOMAIN, "here (%d)", rv);
      return rv;
    }
  }
  rv=AQH_MqttMsg_IsMsgComplete(msg);
  if (rv<0) {
    DBG_INFO(AQH_LOGDOMAIN, "here (%d)", rv);
    return rv;
  }

  return rv;
}



int _calcAndSetPayloadSizeAndOffset(GWEN_MSG *msg)
{
  int remainingBytesInBuffer;
  uint32_t mqttRemainingLength=0;

  remainingBytesInBuffer=GWEN_Msg_GetBytesInBuffer(msg);
  if (remainingBytesInBuffer>1) {
    const uint8_t *ptr;
    int idx;

    ptr=GWEN_Msg_GetConstBuffer(msg);
    idx=1;
    remainingBytesInBuffer--;
    while(remainingBytesInBuffer) {
      uint8_t len;

      len=ptr[idx];
      mqttRemainingLength<<=8;
      mqttRemainingLength+=(len & 0x7f);
      if (!(len & 0x80)) {
        /* last byte of size */
        GWEN_Msg_SetParsedPayloadSize(msg, mqttRemainingLength);
        GWEN_Msg_SetParsedPayloadOffset(msg, idx+1); /* payload follows at next byte */
        GWEN_Msg_AddFlags(msg, GWEN_MSG_FLAGS_PAYLOADINFO_SET);
        return 1; /* size successfully determined */
      }
    }
  }
  return 0;
}