/*******************************************************************************
    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@lists.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  add alcatel 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 0
struct sockaddr_in dest_addr[MAX_INST];
struct sockaddr_in local_addr[MAX_INST];
int addr_len[MAX_INST];


 int eth_socket_init_udp(openair0_device *device) {

  int i = 0;
  eth_state_t *eth = (eth_state_t*)device->priv;
  int Mod_id = device->Mod_id;  
  char str_local[INET_ADDRSTRLEN];
  char str_remote[INET_ADDRSTRLEN];
  const char *local_ip, *remote_ip;
  int local_port=0, remote_port=0;
  int sock_dom=0;
  int sock_type=0;
  int sock_proto=0;
  int enable=1;
  
  if (device->host_type == RRH_HOST ) {
    local_ip   = device->openair0_cfg.my_addr;   
    local_port = device->openair0_cfg.my_port;
    remote_ip   = "0.0.0.0";   
    remote_port =  0;   
    printf("[%s] local ip addr %s port %d\n", "RRH", local_ip, local_port);    
  } else {
    local_ip   = device->openair0_cfg.my_addr;   
    local_port = device->openair0_cfg.my_port;
    remote_ip   = device->openair0_cfg.remote_addr;
    remote_port = device->openair0_cfg.remote_port;  
    printf("[%s] local ip addr %s port %d\n","BBU", local_ip, local_port);    
  }
  
  /* Open socket to send on */
  sock_dom=AF_INET;
  sock_type=SOCK_DGRAM;
  sock_proto=IPPROTO_UDP;
  
  if ((eth->sockfd[Mod_id] = socket(sock_dom, sock_type, sock_proto)) == -1) {
    perror("ETHERNET: Error opening socket");
    exit(0);
  }
  
  /* initialize addresses */
  for (i=0; i< MAX_INST; i++) {
    bzero((void *)&(dest_addr[i]), sizeof(dest_addr[i]));
    bzero((void *)&(local_addr[i]), sizeof(local_addr[i]));
  }

  addr_len[Mod_id] = sizeof(struct sockaddr_in);

  dest_addr[Mod_id].sin_family = AF_INET;
  inet_pton(AF_INET,remote_ip,&(dest_addr[Mod_id].sin_addr.s_addr));
  dest_addr[Mod_id].sin_port=htons(remote_port);
  inet_ntop(AF_INET, &(dest_addr[Mod_id].sin_addr), str_remote, INET_ADDRSTRLEN);


  local_addr[Mod_id].sin_family = AF_INET;
  inet_pton(AF_INET,local_ip,&(local_addr[Mod_id].sin_addr.s_addr));
  local_addr[Mod_id].sin_port=htons(local_port);
  inet_ntop(AF_INET, &(local_addr[Mod_id].sin_addr), str_local, INET_ADDRSTRLEN);

  
  /* set reuse address flag */
  if (setsockopt(eth->sockfd[Mod_id], SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(int))) {
    perror("ETHERNET: Cannot set SO_REUSEADDR option on socket");
    exit(0);
  }
  
  /* apply additional configuration */
  //ethernet_tune (device,MTU_SIZE,UDP_PACKET_SIZE_BYTES(device->openair0_cfg.samples_per_packet));
  
  /* if RRH, then I am the server, so bind */
  if (device->host_type == RRH_HOST) {    
    if (bind(eth->sockfd[Mod_id],(struct sockaddr *)&local_addr[Mod_id],addr_len[Mod_id])<0) {
      perror("ETHERNET: Cannot bind to socket");
      exit(0);
    } else {
      printf("[%s] binding mod_%d to %s:%d\n","RRH",Mod_id,str_local,ntohs(local_addr[Mod_id].sin_port));
    }
    /* if BBU, then I am a client, so connect */ 
  } else {
    printf("[%s] Connecting to %s:%d\n","BBU",str_remote,ntohs(dest_addr[Mod_id].sin_port));
  }
  
  

  return 0;
}

int trx_eth_write_udp(openair0_device *device, openair0_timestamp timestamp, void **buff, int nsamps,int cc, int flags) {	
  
  int bytes_sent=0;
  eth_state_t *eth = (eth_state_t*)device->priv;
  int Mod_id = device->Mod_id;
  int sendto_flag =0;
  int i=0;
  //sendto_flag|=flags;
  eth->tx_nsamps=nsamps;

  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]- APP_HEADER_SIZE_BYTES); 
    
    /* 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));
    
    bytes_sent = 0;
    
    *(int16_t *)(buff2 + sizeof(int16_t))=1+(i<<1);
    *(openair0_timestamp *)(buff2 + sizeof(int32_t)) = timestamp;
    
  
    while(bytes_sent < UDP_PACKET_SIZE_BYTES(nsamps)) {
#if DEBUG   
      printf("------- TX ------: buff2 current position=%d remaining_bytes=%d  bytes_sent=%d \n",
	     (void *)(buff2+bytes_sent), 
	     UDP_PACKET_SIZE_BYTES(nsamps) - bytes_sent,
	     bytes_sent);
#endif
      /* Send packet */
      bytes_sent += sendto(eth->sockfd[Mod_id],
			   buff2, 
                           UDP_PACKET_SIZE_BYTES(nsamps),
			   sendto_flag,
			   (struct sockaddr*)&dest_addr[Mod_id],
			   addr_len[Mod_id]);
      
      if ( bytes_sent == -1) {
	eth->num_tx_errors++;
	perror("ETHERNET WRITE: ");
	exit(-1);
      } else {
#if DEBUG
    printf("------- TX ------: nu=%d an_id=%d ts%d bytes_send=%d\n",
	   *(int16_t *)buff2,
	   *(int16_t *)(buff2 + sizeof(int16_t)),
	   *(openair0_timestamp *)(buff2 + sizeof(int32_t)),
	   bytes_sent);
    dump_packet((device->host_type == BBU_HOST)? "BBU":"RRH", buff2, UDP_PACKET_SIZE_BYTES(nsamps), TX_FLAG);
#endif
    eth->tx_actual_nsamps=bytes_sent>>2;
    eth->tx_count++;
      }
    }              
      /* tx buffer values restored */  
      *(int32_t *)buff2 = temp0;
      *(openair0_timestamp *)(buff2 + sizeof(int32_t)) = temp1;
  }
 
  return (bytes_sent-APP_HEADER_SIZE_BYTES)>>2;
}
      


int trx_eth_read_udp(openair0_device *device, openair0_timestamp *timestamp, void **buff, int nsamps, int cc) {
  
  int bytes_received=0;
  eth_state_t *eth = (eth_state_t*)device->priv;
  openair0_timestamp prev_timestamp = -1;
  int Mod_id = device->Mod_id;
  int rcvfrom_flag =0;
  int block_cnt=0;
  int again_cnt=0;
  int i=0;

  eth->rx_nsamps=nsamps;

  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]- APP_HEADER_SIZE_BYTES);
    
    /* 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;
    
    
    while(bytes_received < UDP_PACKET_SIZE_BYTES(nsamps)) {
    again:
#if DEBUG   
	   printf("------- RX------: buff2 current position=%d remaining_bytes=%d  bytes_recv=%d \n",
		  (void *)(buff2+bytes_received),
		  UDP_PACKET_SIZE_BYTES(nsamps) - bytes_received,
		  bytes_received);
#endif
      bytes_received +=recvfrom(eth->sockfd[Mod_id],
				buff2,
	                        UDP_PACKET_SIZE_BYTES(nsamps),
				rcvfrom_flag,
				(struct sockaddr *)&dest_addr[Mod_id],
				(socklen_t *)&addr_len[Mod_id]);
      
      if (bytes_received ==-1) {
	eth->num_rx_errors++;
	if (errno == EAGAIN) {
	  again_cnt++;
	  usleep(10);
	  if (again_cnt == 1000) {
	  perror("ETHERNET READ: ");
	  exit(-1);
	  } else {
	    printf("AGAIN AGAIN AGAIN AGAIN AGAIN AGAIN AGAIN AGAIN AGAIN AGAIN AGAIN AGAIN \n");
	    goto again;
	  }	  
	} else if (errno == EWOULDBLOCK) {
	     block_cnt++;
	     usleep(10);	  
	     if (block_cnt == 1000) {
      perror("ETHERNET READ: ");
      exit(-1);
    } else {
	    printf("BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK \n");
	    goto again;
	  }
	}
      } else {
#if DEBUG   
	   printf("------- RX------: nu=%d an_id=%d ts%d bytes_recv=%d\n",
		  *(int16_t *)buff2,
		  *(int16_t *)(buff2 + sizeof(int16_t)),
		  *(openair0_timestamp *)(buff2 + sizeof(int32_t)),
		  bytes_received);
	   dump_packet((device->host_type == BBU_HOST)? "BBU":"RRH", buff2, UDP_PACKET_SIZE_BYTES(nsamps),RX_FLAG);	  
#endif  
	   /* store the timestamp value from packet's header */
	   if (prev_timestamp == -1) {
	     prev_timestamp = *(openair0_timestamp *)(buff2 + sizeof(int32_t));
	   } else {
	     prev_timestamp =timestamp;
	   }
	   /* store the timestamp value from packet's header */
	   *timestamp =  *(openair0_timestamp *)(buff2 + sizeof(int32_t));
	   eth->rx_actual_nsamps=bytes_received>>2;
	   eth->rx_count++;
    }	 
      
    }
      /* tx buffer values restored */  
      *(int32_t *)buff2 = temp0;
      *(openair0_timestamp *)(buff2 + sizeof(int32_t)) = temp1;
	  
    }      
  return (bytes_received-APP_HEADER_SIZE_BYTES)>>2;
}
      



int eth_set_dev_conf_udp(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 *)&dest_addr[Mod_id],addr_len[Mod_id])==-1) {
    perror("ETHERNET: ");
    exit(0);
  }

  /* printf("[RRHbbb] mod_%d socket %d connected to BBU %s:%d\n", Mod_id, eth->sockfd[Mod_id], inet_ntoa(dest_addr[Mod_id].sin_addr), */
  /* 	ntohs(dest_addr[Mod_id].sin_port)); */
  return 0;
}

int eth_get_dev_conf_udp(openair0_device *device) {

  eth_state_t   *eth = (eth_state_t*)device->priv;
  int 		Mod_id = device->Mod_id;
  char 		str1[INET_ADDRSTRLEN],str[INET_ADDRSTRLEN];
  void 		*msg;
  ssize_t	msg_len;
  
  msg=malloc(sizeof(openair0_config_t));
  msg_len=sizeof(openair0_config_t);

  inet_ntop(AF_INET, &(local_addr[Mod_id].sin_addr), str, INET_ADDRSTRLEN);
      inet_ntop(AF_INET, &(dest_addr[Mod_id].sin_addr), str1, INET_ADDRSTRLEN);

  /* printf("[RRH] mod_%d socket %d connected to BBU %s:%d %s:%d\n", Mod_id, eth->sockfd[Mod_id], str1, */
  /* 	 ntohs(dest_addr[Mod_id].sin_port),str, */
  /* 	ntohs(local_addr[Mod_id].sin_port)); */
 
  /* RRH receives from BBU openair0_config_t */
  if (recvfrom(eth->sockfd[Mod_id],
	       msg,
	       msg_len,
	       0,
	       (struct sockaddr *)&dest_addr[Mod_id],
	       (socklen_t *)&addr_len[Mod_id])==-1) {
    perror("ETHERNET: ");
    exit(0);
  }
		
   memcpy((void*)&device->openair0_cfg,msg,msg_len);

   /* get remote ip address and port */
   inet_ntop(AF_INET, &(dest_addr[Mod_id].sin_addr), str1, INET_ADDRSTRLEN);
   device->openair0_cfg.remote_port =ntohs(dest_addr[Mod_id].sin_port);
   device->openair0_cfg.remote_addr =str1;

   /* restore local ip address and port */
   inet_ntop(AF_INET, &(local_addr[Mod_id].sin_addr), str, INET_ADDRSTRLEN);
   device->openair0_cfg.my_port =ntohs(local_addr[Mod_id].sin_port);
   device->openair0_cfg.my_addr =str;

   /* printf("[RRH2] mod_%d socket %d connected to BBU %s:%d  %s:%d\n", Mod_id, eth->sockfd[Mod_id],str1, device->openair0_cfg.remote_port, str, device->openair0_cfg.my_port); */
   return 0;
}