/*******************************************************************************
    OpenAirInterface
    Copyright(c) 1999 - 2014 Eurecom

    OpenAirInterface 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 3 of the License, or
    (at your option) any later version.


    OpenAirInterface 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 OpenAirInterface.The full GNU General Public License is
    included in this distribution in the file called "COPYING". If not,
    see <http://www.gnu.org/licenses/>.

   Contact Information
   OpenAirInterface Admin: openair_admin@eurecom.fr
   OpenAirInterface Tech : openair_tech@eurecom.fr
   OpenAirInterface Dev  : openair4g-devel@eurecom.fr

   Address      : Eurecom, Campus SophiaTech, 450 Route des Chappes, CS 50193 - 06904 Biot Sophia Antipolis cedex, FRANCE

 *******************************************************************************/
/*! \file ethernet_lib.c 
 * \brief API to stream I/Q samples over standard ethernet
 * \author Katerina Trilyraki, Navid Nikaein, Pedro Dinis, Lucio Ferreira, Raymond Knopp
 * \date 2015
 * \version 0.2
 * \company Eurecom
 * \maintainer:  navid.nikaein@eurecom.fr
 * \note
 * \warning 
 */

#include <arpa/inet.h>
#include <linux/if_packet.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/ether.h>
#include <unistd.h>
#include <errno.h>

#include "common_lib.h"
#include "ethernet_lib.h"

//#define DEBUG 1

int num_devices_eth = 0;
int dest_addr_len[MAX_INST];
char sendbuf[MAX_INST][BUF_SIZ]; /*TODO*/


/*! \fn static int eth_socket_init(openair0_device *device)
* \brief initialization of UDP Socket to communicate with one destination
* \param[in] *device openair device for which the socket will be created
* \param[out]
* \return 0 on success, otherwise -1
* \note
* @ingroup  _oai
*/
static int eth_socket_init(openair0_device *device);

/*! \fn static int eth_set_dev_conf(openair0_device *device)
* \brief 
* \param[in] *device openair device 
* \param[out]
* \return 0 on success, otherwise -1
* \note
* @ingroup  _oai
*/
static int eth_set_dev_conf(openair0_device *device);

/*! \fn static int eth_get_dev_conf(openair0_device *device)
* \brief
* \param[in] *device openair device
* \param[out]
* \return 0 on success, otherwise -1
* \note
* @ingroup  _oai
*/
static int eth_get_dev_conf(openair0_device *device);



int trx_eth_start(openair0_device *device) {
  
  /* initialize socket */
  if (eth_socket_init(device)!=0) {
    return -1;
  }
  
  /* RRH gets openair0 device configuration BBU sets openair0 device configuration*/
  if (device->func_type == BBU_FUNC) {
    return eth_set_dev_conf(device);
  } else {
    return eth_get_dev_conf(device);
  }

  return 0;
}


int trx_eth_write(openair0_device *device, openair0_timestamp timestamp, void **buff, int nsamps,int cc, int flags) {	
  
  int n_written=0,i;
  uint16_t header_size=sizeof(int32_t) + sizeof(openair0_timestamp);
  eth_state_t *eth = (eth_state_t*)device->priv;
  int Mod_id = device->Mod_id;
  int sendto_flag =0;
  sendto_flag|=MSG_DONTWAIT;
  
  for (i=0;i<cc;i++) {	
    /* buff[i] points to the position in tx buffer where the payload to be sent is
       buff2 points to the position in tx buffer where the packet header will be placed */
    void *buff2 = (void*)(buff[i]-header_size); 
    
    /* we don't want to ovewrite with the header info the previous tx buffer data so we store it*/
    int32_t temp0 = *(int32_t *)buff2;
    openair0_timestamp  temp1 = *(openair0_timestamp *)(buff2 + sizeof(int32_t));
    
    n_written = 0;
    
    *(int16_t *)(buff2 + sizeof(int16_t))=1+(i<<1);
    *(openair0_timestamp *)(buff2 + sizeof(int32_t)) = timestamp;
    
    /* printf("[RRH]write mod_%d %d , len %d, buff %p antenna %d\n",
       Mod_id,eth->sockfd[Mod_id],(nsamps<<2)+header_size, buff2, antenna_id);*/
    
    while(n_written < nsamps) {
      /* Send packet */
      if ((n_written += sendto(eth->sockfd[Mod_id],
			       buff2, 
			       (nsamps<<2)+header_size,
			       0,
			       (struct sockaddr*)&eth->dest_addr[Mod_id],
			       dest_addr_len[Mod_id])) < 0) {
	perror("ETHERNET WRITE");
	exit(-1);
      }
    }

#if DEBUG
    printf("Buffer head TX: nu=%d an_id=%d ts%d samples_send=%d i=%d data=%x\n",
	   *(int16_t *)buff2,
	   *(int16_t *)(buff2 + sizeof(int16_t)),
	   *(openair0_timestamp *)(buff2 + sizeof(int32_t)),
	   n_written>>2,i,*(int32_t *)(buff2 + 20*sizeof(int32_t)));
#endif

    /* tx buffer values restored */  
    *(int32_t *)buff2 = temp0;
    *(openair0_timestamp *)(buff2 + sizeof(int32_t)) = temp1;
  }
  return n_written;
  
}

int trx_eth_read(openair0_device *device, openair0_timestamp *timestamp, void **buff, int nsamps, int cc) {

  int bytes_received=0;
  int block_cnt=0;
  int ret=0,i;
  uint16_t  header_size=sizeof(int32_t) + sizeof(openair0_timestamp);

  eth_state_t *eth = (eth_state_t*)device->priv;
  int Mod_id = device->Mod_id;
  
  for (i=0;i<cc;i++) {
    /* buff[i] points to the position in rx buffer where the payload to be received will be placed
       buff2 points to the position in rx buffer where the packet header will be placed */
    void *buff2 = (void*)(buff[i]-header_size);
    
    /* we don't want to ovewrite with the header info the previous rx buffer data so we store it*/
    int32_t temp0 = *(int32_t *)buff2;
    openair0_timestamp temp1 = *(openair0_timestamp *)(buff2 + sizeof(int32_t));
    
    bytes_received=0;
    block_cnt=0;
    ret=0;
    
    /* printf("[RRH] read mod_%d %d,len %d, buff %p antenna %d\n",
       Mod_id,eth->sockfd[Mod_id],(nsamps<<2)+header_size, buff2, antenna_id);*/
    
    while(bytes_received < (int)((nsamps<<2))) {
      ret=recvfrom(eth->sockfd[Mod_id],
		   buff2+bytes_received,
		   (nsamps<<2)+header_size-bytes_received,
		   0,//MSG_DONTWAIT,
                 (struct sockaddr *)&eth->dest_addr[Mod_id],
		   (socklen_t *)&dest_addr_len[Mod_id]);
      
      if (ret==-1) {
	if (errno == EAGAIN) {
	  perror("ETHERNET READ: ");
	  return((nsamps<<2) + header_size);
	} else if (errno == EWOULDBLOCK) {
	  block_cnt++;
	  usleep(10);
	  
	  if (block_cnt == 100) return(-1);
	}
      } else {
	bytes_received+=ret;
      }
    }

#if DEBUG   
    printf("Buffer head RX: nu=%d an_id=%d ts%d samples_recv=%d i=%d data=%x\n",
	   *(int16_t *)buff2,
	   *(int16_t *)(buff2 + sizeof(int16_t)),
	   *(openair0_timestamp *)(buff2 + sizeof(int32_t)),
	   ret>>2,i,*(int32_t *)(buff2 + 20*sizeof(int32_t)));
#endif  

    /* store the timestamp value from packet's header */
    *timestamp =  *(openair0_timestamp *)(buff2 + sizeof(int32_t));
    
    /* tx buffer values restored */  
    *(int32_t *)buff2 = temp0;
    *(openair0_timestamp *)(buff2 + sizeof(int32_t)) = temp1;
  }
  return nsamps;
  
}

void trx_eth_end(openair0_device *device) {

  eth_state_t *eth = (eth_state_t*)device->priv;
  int Mod_id = device->Mod_id;
  /*destroys socket only for the processes that call the eth_end fuction-- shutdown() for beaking the pipe */
  if ( close(eth->sockfd[Mod_id]) <0 ) {
    perror("ETHERNET: Failed to close socket");
    exit(0);
   } else {
    printf("[RRH] socket for mod_id %d has been successfully closed.\n",Mod_id);
   }
 
}


int trx_eth_request(openair0_device *device, void *msg, ssize_t msg_len) {

  int 	       Mod_id = device->Mod_id;
  eth_state_t *eth = (eth_state_t*)device->priv;
 
  /* BBU sends a message to RRH */
 if (sendto(eth->sockfd[Mod_id],msg,msg_len,0,(struct sockaddr *)&eth->dest_addr[Mod_id],dest_addr_len[Mod_id])==-1) {
    perror("ETHERNET: ");
    exit(0);
  }
     
  return 0;
}



int trx_eth_reply(openair0_device *device, void *msg, ssize_t msg_len) {

  eth_state_t   *eth = (eth_state_t*)device->priv;
  int 		Mod_id = device->Mod_id;

  /* RRH receives from BBU a message */
  if (recvfrom(eth->sockfd[Mod_id],
	       msg,
	       msg_len,
	       0,
	       (struct sockaddr *)&eth->dest_addr[Mod_id],
	       (socklen_t *)&dest_addr_len[Mod_id])==-1) {
    perror("ETHERNET: ");
    exit(0);
  }	
 
   return 0;
}


static int eth_set_dev_conf(openair0_device *device) {

  int 	       Mod_id = device->Mod_id;
  eth_state_t *eth = (eth_state_t*)device->priv;
  void 	      *msg;
  ssize_t      msg_len;

  
  /* a BBU client sents to RRH a set of configuration parameters (openair0_config_t)
     so that RF front end is configured appropriately and
     frame/packet size etc. can be set */ 
  
  msg=malloc(sizeof(openair0_config_t));
  msg_len=sizeof(openair0_config_t);
  memcpy(msg,(void*)&device->openair0_cfg,msg_len);	
  
  if (sendto(eth->sockfd[Mod_id],msg,msg_len,0,(struct sockaddr *)&eth->dest_addr[Mod_id],dest_addr_len[Mod_id])==-1) {
    perror("ETHERNET: ");
    exit(0);
  }
     
  return 0;
}


static int eth_get_dev_conf(openair0_device *device) {

  eth_state_t   *eth = (eth_state_t*)device->priv;
  int 		Mod_id = device->Mod_id;
  char 		str[INET_ADDRSTRLEN];
  void 		*msg;
  ssize_t	msg_len;
  
  msg=malloc(sizeof(openair0_config_t));
  msg_len=sizeof(openair0_config_t);

  /* RRH receives from BBU openair0_config_t */
  if (recvfrom(eth->sockfd[Mod_id],
	       msg,
	       msg_len,
	       0,
	       (struct sockaddr *)&eth->dest_addr[Mod_id],
	       (socklen_t *)&dest_addr_len[Mod_id])==-1) {
    perror("ETHERNET: ");
    exit(0);
  }
		
   memcpy((void*)&device->openair0_cfg,msg,msg_len);	
   inet_ntop(AF_INET, &(eth->dest_addr[Mod_id].sin_addr), str, INET_ADDRSTRLEN);
   device->openair0_cfg.remote_port =ntohs(eth->dest_addr[Mod_id].sin_port);
   device->openair0_cfg.remote_ip=str;
   /*apply additional configuration*/
   //ethernet_tune (device, RING_PAR);
   // printf("[RRH] write mod_%d %d to %s:%d\n",Mod_id,eth->sockfd[Mod_id],str,ntohs(eth->dest_addr[Mod_id].sin_port));

   return 0;
}



int trx_eth_stop(int card) {
  return(0);
}

int trx_eth_set_freq(openair0_device* device, openair0_config_t *openair0_cfg,int exmimo_dump_config) {
  return(0);
}

int trx_eth_set_gains(openair0_device* device, openair0_config_t *openair0_cfg) {
  return(0);
}

int trx_eth_get_stats(openair0_device* device) {
  return(0);
}

int trx_eth_reset_stats(openair0_device* device) {
  return(0);
}


static int eth_socket_init(openair0_device *device) {

  int i = 0;
  eth_state_t *eth = (eth_state_t*)device->priv;
  int Mod_id = device->Mod_id;  
  char str[INET_ADDRSTRLEN];
  const char *dest_ip;
  int dest_port=0;
  
  if (device->func_type == RRH_FUNC ) {
    dest_ip   = device->openair0_cfg.my_ip;   
    dest_port = device->openair0_cfg.my_port;
    printf("[RRH] ip addr %s port %d\n",dest_ip, dest_port);
  } else {
    dest_ip   = device->openair0_cfg.remote_ip;
    dest_port = device->openair0_cfg.remote_port;
    printf("[BBU] ip addr %s port %d\n",dest_ip, dest_port);
  }
    
  /* Open RAW socket to send on */
  if ((eth->sockfd[Mod_id] = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) {
    perror("ETHERNET: Error opening socket");
    exit(0);
  }

  /* initialize destination address */
  for (i=0; i< MAX_INST; i++) {
    bzero((void *)&(eth->dest_addr[i]), sizeof(eth->dest_addr[i]));
  }

 // bzero((void *)dest,sizeof(struct sockaddr_in));
  eth->dest_addr[Mod_id].sin_family = AF_INET;
  inet_pton(AF_INET,dest_ip,&(eth->dest_addr[Mod_id].sin_addr.s_addr));
  eth->dest_addr[Mod_id].sin_port=htons(dest_port);
  dest_addr_len[Mod_id] = sizeof(struct sockaddr_in);
  inet_ntop(AF_INET, &(eth->dest_addr[Mod_id].sin_addr), str, INET_ADDRSTRLEN);
  
  /* if RRH, then I am the server, so bind */
  if (device->func_type == RRH_FUNC ) {    
    if (bind(eth->sockfd[Mod_id],(struct sockaddr *)&eth->dest_addr[Mod_id], dest_addr_len[Mod_id])<0) {
      perror("ETHERNET: Cannot bind to socket");
      exit(0);
    } else {
      printf("[RRH] binding mod_%d to %s:%d\n",Mod_id,str,ntohs(eth->dest_addr[Mod_id].sin_port));
    }
    
  } else {
    printf("[BBU] Connecting to %s:%d\n",str,ntohs(eth->dest_addr[Mod_id].sin_port));
  }
  
  return 0;
}


int ethernet_tune(openair0_device *device , eth_opt_t option) {
  
  eth_state_t *eth = (eth_state_t*)device->priv;
  int Mod_id=device->Mod_id;
  
  unsigned int sndbuf_size=0, rcvbuf_size=0;
  struct timeval snd_timeout, rcv_timeout;
  struct ifreq ifr;   
  char system_cmd[256]; 
  char* if_name=DEFAULT_IF;

  /****************** socket level options ************************/
  if (option== SND_BUF_SIZE) {    /* transmit socket buffer size */   
    if (setsockopt(eth->sockfd[Mod_id],  
		   SOL_SOCKET,  
		   SO_SNDBUF,  
		   &sndbuf_size,sizeof(sndbuf_size))) {
      perror("[ETHERNET] setsockopt()");
    } else {
      printf( "sndbuf_size= %d bytes\n", sndbuf_size); 
    }     
  } else if (option== RCV_BUF_SIZE) {  /* receive socket buffer size */   
    if (setsockopt(eth->sockfd[Mod_id],  
		   SOL_SOCKET,  
		   SO_RCVBUF,  
		   &rcvbuf_size,sizeof(rcvbuf_size))) {
      perror("[ETHERNET] setsockopt()");
    } else {     
      printf( "rcvbuf_size= %d bytes\n", rcvbuf_size);    
    }
  } else if (option==RCV_TIMEOUT) {
    rcv_timeout.tv_sec = 0;
    rcv_timeout.tv_usec = 180;//less than rt_period
    if (setsockopt(eth->sockfd[Mod_id],  
		   SOL_SOCKET,  
		   SO_RCVTIMEO,  
		   (char *)&rcv_timeout,sizeof(rcv_timeout))) {
      perror("[ETHERNET] setsockopt()");  
    } else {   
      printf( "rcv_timeout= %d usecs\n", rcv_timeout.tv_usec);  
    }  
  } else if (option==SND_TIMEOUT) {
    snd_timeout.tv_sec = 0;
    snd_timeout.tv_usec = 180;//less than rt_period
    if (setsockopt(eth->sockfd[Mod_id],  
		   SOL_SOCKET,  
		   SO_SNDTIMEO,  
		   (char *)&snd_timeout,sizeof(snd_timeout))) {
      perror("[ETHERNET] setsockopt()");     
    } else {
      printf( "snd_timeout= %d usecs\n", snd_timeout.tv_usec);    
    }
  }
  
  /******************* interface level options  *************************/
  else if (option==MTU_SIZE) {    /* change  MTU of the eth interface */ 
    ifr.ifr_addr.sa_family = AF_INET;
    strncpy(ifr.ifr_name,if_name, sizeof(ifr.ifr_name));
    ifr.ifr_mtu =8960;
    if (ioctl(eth->sockfd[Mod_id],SIOCSIFMTU,(caddr_t)&ifr) < 0 )
      perror ("[ETHERNET] Can't set the MTU");
    else 
      printf("[ETHERNET] %s MTU size has changed to %d\n",DEFAULT_IF,ifr.ifr_mtu);
  } else if (option==TX_Q_LEN) {    /* change TX queue length of eth interface */ 
    ifr.ifr_addr.sa_family = AF_INET;
    strncpy(ifr.ifr_name,if_name, sizeof(ifr.ifr_name));
    ifr.ifr_qlen =3000 ;
    if (ioctl(eth->sockfd[Mod_id],SIOCSIFTXQLEN,(caddr_t)&ifr) < 0 )
      perror ("[ETHERNET] Can't set the txqueuelen");
    else 
      printf("[ETHERNET] %s txqueuelen size has changed to %d\n",DEFAULT_IF,ifr.ifr_qlen);


    /******************* device level options  *************************/
  } else if (option==COALESCE_PAR) {  
    if (snprintf(system_cmd,sizeof(system_cmd),"ethtool -C %s rx-usecs 3",DEFAULT_IF) > 0) {
      system(system_cmd);
      printf("[ETHERNET] Coalesce parameters %s\n",system_cmd);
    } else {
      perror("[ETHERNET] Can't set coalesce parameters\n");
    }
    
  } else if (option==PAUSE_PAR ) {  
    if (snprintf(system_cmd,sizeof(system_cmd),"ethtool -A %s autoneg off rx off tx off",DEFAULT_IF) > 0) {
      system(system_cmd);
      printf("[ETHERNET] Pause parameters %s\n",system_cmd);
    } else {
      perror("[ETHERNET] Can't set pause parameters\n");
    }
  } else if (option==RING_PAR ) {  
    if (snprintf(system_cmd,sizeof(system_cmd),"ethtool -G %s rx 4096 tx 4096",DEFAULT_IF) > 0) {
      system(system_cmd);
      printf("[ETHERNET] Ring parameters %s\n",system_cmd);
    } else {
      perror("[ETHERNET] Can't set ring parameters\n");
    }
    
  }
  return 0;
}



int openair0_dev_init_eth(openair0_device *device, openair0_config_t *openair0_cfg) {

  eth_state_t *eth = (eth_state_t*)malloc(sizeof(eth_state_t));
  int card = 0;
  memset(eth, 0, sizeof(eth_state_t));
  eth->buffer_size =  (unsigned int)openair0_cfg[card].samples_per_packet*sizeof(int32_t); // buffer size = 4096 for sample_len of 1024
  eth->sample_rate = (unsigned int)openair0_cfg[card].sample_rate;
  device->priv = eth; 	

  printf("ETHERNET: Initializing openair0_device for %s ...\n", ((device->func_type == BBU_FUNC) ? "BBU": "RRH"));
  device->Mod_id           = num_devices_eth++;
  device->trx_start_func   = trx_eth_start;
  device->trx_request_func = trx_eth_request;
  device->trx_reply_func   = trx_eth_reply;
  device->trx_write_func   = trx_eth_write;
  device->trx_read_func    = trx_eth_read;  
  device->trx_get_stats_func   = trx_eth_get_stats;
  device->trx_reset_stats_func = trx_eth_reset_stats;
  device->trx_end_func = trx_eth_end;
  device->trx_stop_func = trx_eth_stop;
  device->trx_set_freq_func = trx_eth_set_freq;
  device->trx_set_gains_func = trx_eth_set_gains;
  
  memcpy((void*)&device->openair0_cfg,(void*)openair0_cfg,sizeof(openair0_config_t));
  return 0;
}