#include <stdio.h>

#include <sys/types.h>
#include <sys/socket.h>
#include <stdlib.h>
#include <unistd.h>
#include <netinet/in.h>

#include "ldp_struct.h"
#include "ldp_prefix.h"
#include "ldp_netlink.h"
#include "ldp_fib_impl.h"
#include "ldp_tree_impl.h"

extern int _netlink_fd;
ldp_fib_callback _netlink_fib_callback = NULL;
ldp_tree_handle _fib_tree = NULL;

extern uint32_t _ldp_ifmgr_find_name(uint32_t handle,uint8_t* name);

int _mask_length(uint32_t bits) {
  int num = 0;

  while (bits != 0) {
    num++;
    bits &= bits-1;
  }
  return num;
}

void ldp_fib_update_close(ldp_fib_handle handle) {
  _netlink_fib_callback = NULL;
  close(_netlink_fd);
}

ldp_bool
ldp_fib_handle_verify(ldp_fib_handle handle) {
  return LDP_TRUE;
}

ldp_fib_handle ldp_fib_open(const ldp_instance_handle handle,
          const ldp_cfg_handle cfg,ldp_fib_callback callback) {
  ldp_tree_handle t = ldp_tree_create(32);
  FILE *fp=fopen("/proc/net/route", "r");
  char buff[4096],iFace[16];
  char gateAddr[128],netAddr[128];
  char maskAddr[128];
  int num,iFlags,metric,refCnt,use,mss,window,irtt;
  ldp_prefix* pfx;
  int temp;

  _fib_tree = t;

  fgets(buff,1023,fp);

  while(fgets(buff,1023,fp)) {
    memset(iFace, 0, 16);
    memset(netAddr, 0, 128);
    memset(gateAddr, 0, 128);
    memset(maskAddr, 0, 128);
    metric = 0;

    num = sscanf(buff,"%16s %128s %128s %X %d %d %d %128s %d %d %d\n",
      iFace,netAddr,gateAddr,
      &iFlags,&refCnt,&use,&metric,maskAddr,
      &mss,&window,&irtt);

    if(!(iFlags & 1)) continue;

    pfx = ldp_prefix_create();

    pfx->network.protocol = AF_INET;
    pfx->network.u.ipv4 = ntohl(strtol(netAddr,NULL,16));

    pfx->next_hop.protocol = AF_INET;
    pfx->next_hop.u.ipv4 = ntohl(strtol(gateAddr,NULL,16));

    pfx->index = 0;
    if(!strcmp(maskAddr,"FFFFFFFF")) {
      pfx->prefix_len = 32;
    } else {
      temp = strtol(maskAddr,NULL,16);
      pfx->prefix_len = _mask_length(temp);
    }

    /* find if handle */
    pfx->out_if_handle = _ldp_ifmgr_find_name(0,iFace);

    fprintf(stderr,"Adding route %08x/%d via %d",pfx->network.u.ipv4,
      pfx->prefix_len,pfx->out_if_handle);
    if(ldp_tree_insert(t,pfx->network.u.ipv4,pfx->prefix_len,(void*)pfx) ==
      LDP_FAILURE) {
      fprintf(stderr," - failed");
    }
    fprintf(stderr,"\n");
  }
  fclose(fp);

  if(_netlink_fd == 0) {
    _netlink_fd = rtnl_open();
  }
  _netlink_fib_callback = callback;

  return t;
}

int ldp_fib_get_route(ldp_fib_handle handle,const int num,
  const ldp_prefix* dest,ldp_prefix* entry) {
  ldp_prefix* pfx = NULL;

  if(dest == NULL)
    return LDP_FAILURE;

  if(ldp_tree_get(handle,dest->network.u.ipv4,dest->prefix_len,(void**)&pfx) == 
    LDP_FAILURE) {
    return LDP_FAILURE;
  }

  if(pfx == 0) {
    return LDP_FAILURE;
  }

  memcpy(entry,pfx,sizeof(ldp_prefix));
  return 1;
}

int ldp_fib_get_best_route(ldp_fib_handle handle,const int num,
  const ldp_prefix* dest,ldp_prefix* entry) {
  ldp_prefix *pfx = NULL;

  if(dest == NULL)
    return 0;

  if(ldp_tree_get_longest(handle,dest->network.u.ipv4,(void**)&pfx) == 
    LDP_FAILURE) {
    return 0;
  }

  memcpy(entry,pfx,sizeof(ldp_prefix));
  return 1;
}

ldp_return_enum ldp_fib_getfirst_route(ldp_fib_handle handle,ldp_prefix* dest) {
  return LDP_FAILURE;
}

ldp_return_enum ldp_fib_getnext_route(ldp_fib_handle handle,ldp_prefix* dest) {
  return LDP_FAILURE;
}

void ldp_fib_close(ldp_fib_handle handle) {
  if(ldp_tree_handle_verify(handle) == LDP_TRUE) {
    ldp_tree_delete(handle);
  }
}