/****************************************************************************
 * net/procfs/netdev_statistics.c
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <sys/types.h>
#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#include <assert.h>
#include <debug.h>

#include <netinet/ether.h>

#include <nuttx/net/netdev.h>
#include <nuttx/net/sixlowpan.h>

#include "inet/inet.h"
#include "netdev/netdev.h"
#include "utils/utils.h"
#include "procfs/procfs.h"

#if !defined(CONFIG_DISABLE_MOUNTPOINT) && defined(CONFIG_FS_PROCFS) && \
    !defined(CONFIG_FS_PROCFS_EXCLUDE_NET)

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

#ifdef CONFIG_NET_IPv4
#  define NETSTAT_IPv6_IDX 2
#else
#  define NETSTAT_IPv6_IDX 1
#endif

/****************************************************************************
 * Private Function Prototypes
 ****************************************************************************/

static int netprocfs_linklayer(FAR struct netprocfs_file_s *netfile);
#ifdef CONFIG_NET_IPv4
static int netprocfs_inet4addresses(FAR struct netprocfs_file_s *netfile);
#endif
#ifdef CONFIG_NET_IPv6
static int netprocfs_inet6address(FAR struct netprocfs_file_s *netfile);
static int netprocfs_inet6draddress(FAR struct netprocfs_file_s *netfile);
#endif
#if !defined(CONFIG_NET_IPv4) && !defined(CONFIG_NET_IPv6)
static int netprocfs_blank_line(FAR struct netprocfs_file_s *netfile);
#endif
#ifdef CONFIG_NETDEV_STATISTICS
static int netprocfs_rxstatistics_header(
    FAR struct netprocfs_file_s *netfile);
static int netprocfs_rxstatistics(FAR struct netprocfs_file_s *netfile);
static int netprocfs_rxpackets_header(FAR struct netprocfs_file_s *netfile);
static int netprocfs_rxpackets(FAR struct netprocfs_file_s *netfile);
static int netprocfs_txstatistics_header(
    FAR struct netprocfs_file_s *netfile);
static int netprocfs_txstatistics(FAR struct netprocfs_file_s *netfile);
static int netprocfs_errors(FAR struct netprocfs_file_s *netfile);
#endif /* CONFIG_NETDEV_STATISTICS */

/****************************************************************************
 * Private Data
 ****************************************************************************/

/* Line generating functions */

static const linegen_t g_netstat_linegen[] =
{
  netprocfs_linklayer
#ifdef CONFIG_NET_IPv4
  , netprocfs_inet4addresses
#endif
#ifdef CONFIG_NET_IPv6
#  if defined(CONFIG_NETDEV_MULTIPLE_IPv6) && \
      defined(CONFIG_DESIGNATED_INITIALIZERS)
  , [NETSTAT_IPv6_IDX ... NETSTAT_IPv6_IDX + CONFIG_NETDEV_MAX_IPv6_ADDR - 1]
  = netprocfs_inet6address
#  else
  , netprocfs_inet6address
#  endif
  , netprocfs_inet6draddress
#endif
#if !defined(CONFIG_NET_IPv4) && !defined(CONFIG_NET_IPv6)
  , netprocfs_blank_line
#endif

#ifdef CONFIG_NETDEV_STATISTICS
  , netprocfs_rxstatistics_header,
  netprocfs_rxstatistics,
  netprocfs_rxpackets_header,
  netprocfs_rxpackets,
  netprocfs_txstatistics_header,
  netprocfs_txstatistics,
  netprocfs_errors
#endif /* CONFIG_NETDEV_STATISTICS */
};

#define NSTAT_LINES (sizeof(g_netstat_linegen) / sizeof(linegen_t))

/****************************************************************************
 * Private Functions
 ****************************************************************************/

#if defined(CONFIG_NET_6LOWPAN) || defined(CONFIG_NET_IEEE802154)
static int netprocfs_radio_linklayer(FAR struct netprocfs_file_s *netfile,
                                       int len)
{
  FAR struct netdev_varaddr_s *addr;
  FAR struct net_driver_s *dev;
#if RADIO_MAX_ADDRLEN > 1
  int i;
#endif

  DEBUGASSERT(netfile != NULL && netfile->dev != NULL);
  dev  = netfile->dev;
  addr = &dev->d_mac.radio;

#ifdef CONFIG_NET_6LOWPAN
  len += snprintf(&netfile->line[len], NET_LINELEN - len,
                  "%s\tLink encap:6LoWPAN HWaddr ",
                  dev->d_ifname);
#else
  len += snprintf(&netfile->line[len], NET_LINELEN - len,
                  "%s\tLink encap:Raw HWaddr ",
                  dev->d_ifname);
#endif

  if (addr->nv_addrlen < 1 || addr->nv_addrlen > RADIO_MAX_ADDRLEN)
    {
      nwarn("WARNING: Bad or undefined node address: %u\n",
            addr->nv_addrlen);

      len += snprintf(&netfile->line[len], NET_LINELEN - len,
                      "--");
    }
  else
    {
      len += snprintf(&netfile->line[len], NET_LINELEN - len,
                      "%02x", addr->nv_addr[0]);

#if RADIO_MAX_ADDRLEN > 1  /* Avoids a warning */
      for (i = 1; i < addr->nv_addrlen; i++)
        {
          len += snprintf(&netfile->line[len], NET_LINELEN - len,
                          ":%02x", addr->nv_addr[i]);
        }
#endif
    }

  return len;
}
#endif

/****************************************************************************
 * Name: netprocfs_linklayer
 ****************************************************************************/

static int netprocfs_linklayer(FAR struct netprocfs_file_s *netfile)
{
  FAR struct net_driver_s *dev;
  FAR const char *status;
  int len = 0;

  DEBUGASSERT(netfile != NULL && netfile->dev != NULL);
  dev = netfile->dev;

  /* Get the interface status:  RUNNING, UP, or DOWN */

  if ((dev->d_flags & IFF_RUNNING) != 0)
    {
      status = "RUNNING";
    }
  else if ((dev->d_flags & IFF_UP) != 0)
    {
      status = "UP";
    }
  else
    {
      status = "DOWN";
    }

  /* Select the output appropriate for the link type associated with
   * this device.
   */

  switch (dev->d_lltype)
    {
#if defined(CONFIG_NET_ETHERNET) || defined(CONFIG_DRIVERS_IEEE80211)
      case NET_LL_ETHERNET:
      case NET_LL_IEEE80211:
        {
          char hwaddr[20];
          len += snprintf(&netfile->line[len], NET_LINELEN - len,
                          "%s\tLink encap:Ethernet HWaddr %s",
                          dev->d_ifname,
                          ether_ntoa_r(&dev->d_mac.ether, hwaddr));
        }
        break;
#endif

#if defined(CONFIG_NET_6LOWPAN) || defined(CONFIG_NET_IEEE802154)
      case NET_LL_IEEE802154:
      case NET_LL_PKTRADIO:
        {
          len += netprocfs_radio_linklayer(netfile, len);
        }
        break;
#endif /* CONFIG_NET_6LOWPAN || CONFIG_NET_IEEE802154 */

#ifdef CONFIG_NET_LOOPBACK
      case NET_LL_LOOPBACK:
        len += snprintf(&netfile->line[len], NET_LINELEN - len,
                        "%s\tLink encap:Local Loopback",
                        dev->d_ifname);
        break;
#endif

#ifdef CONFIG_NET_SLIP
      case NET_LL_SLIP:
        len += snprintf(&netfile->line[len], NET_LINELEN - len,
                        "%s\tLink encap:SLIP", dev->d_ifname);
        break;
#endif

#ifdef CONFIG_NET_PPP
      case NET_LL_PPP:
        len += snprintf(&netfile->line[len], NET_LINELEN - len,
                        "%s\tLink encap:P-t-P", dev->d_ifname);
        break;
#endif

#ifdef CONFIG_NET_TUN
      case NET_LL_TUN:
        len += snprintf(&netfile->line[len], NET_LINELEN - len,
                        "%s\tLink encap:TUN", dev->d_ifname);
        break;
#endif

      default:
        len += snprintf(&netfile->line[len], NET_LINELEN - len,
                        "%s\tLink encap:UNSPEC", dev->d_ifname);
    }

  len += snprintf(&netfile->line[len], NET_LINELEN - len,
                  " at %s", status);

  len += snprintf(&netfile->line[len], NET_LINELEN - len,
                  " mtu %d\n", (dev->d_pktsize - dev->d_llhdrlen));
  return len;
}

/****************************************************************************
 * Name: netprocfs_inet4addresses
 ****************************************************************************/

#ifdef CONFIG_NET_IPv4
static int netprocfs_inet4addresses(FAR struct netprocfs_file_s *netfile)
{
  FAR struct net_driver_s *dev;
  struct in_addr addr;
  int len = 0;
  char inetaddr[INET_ADDRSTRLEN];

  DEBUGASSERT(netfile != NULL && netfile->dev != NULL);
  dev = netfile->dev;

  /* Show the IPv4 address */

  addr.s_addr = dev->d_ipaddr;
  len += snprintf(&netfile->line[len], NET_LINELEN - len,
                  "\tinet addr:%s ", inet_ntoa_r(addr, inetaddr,
                                                 sizeof(inetaddr)));
#ifdef CONFIG_NET_ARP_ACD
  if (dev->d_acd.conflict_flag == ARP_ACD_ADDRESS_CONFLICT)
    {
      len += snprintf(&netfile->line[len], NET_LINELEN - len,
                      "(conflict!) ");
    }
#endif

  /* Show the IPv4 default router address */

  addr.s_addr = dev->d_draddr;
  len += snprintf(&netfile->line[len], NET_LINELEN - len,
                  "DRaddr:%s ", inet_ntoa_r(addr, inetaddr,
                                            sizeof(inetaddr)));

  /* Show the IPv4 network mask */

  addr.s_addr = dev->d_netmask;
  len += snprintf(&netfile->line[len], NET_LINELEN - len,
#ifdef CONFIG_NET_IPv6
                  "Mask:%s\n",    /* IPv6 addresses will follow */
#else
                  "Mask:%s\n\n",  /* Double space at end of device description */
#endif
                  inet_ntoa_r(addr, inetaddr, sizeof(inetaddr)));

  return len;
}
#endif

/****************************************************************************
 * Name: netprocfs_inet6address
 ****************************************************************************/

#ifdef CONFIG_NET_IPv6
static int netprocfs_inet6address(FAR struct netprocfs_file_s *netfile)
{
  FAR struct net_driver_s *dev;
  char addrstr[INET6_ADDRSTRLEN];
  uint8_t preflen;
  int idx = netfile->lineno - NETSTAT_IPv6_IDX;
  int len = 0;

  DEBUGASSERT(netfile != NULL && netfile->dev != NULL);
  dev = netfile->dev;

#ifdef CONFIG_NETDEV_MULTIPLE_IPv6
  if (net_ipv6addr_cmp(dev->d_ipv6[idx].addr, g_ipv6_unspecaddr))
    {
      return 0;
    }
#endif

  /* Convert the 128 network mask to a human friendly prefix length */

  preflen = net_ipv6_mask2pref(dev->d_ipv6[idx].mask);

  /* Show the assigned IPv6 address */

  if (inet_ntop(AF_INET6, dev->d_ipv6[idx].addr, addrstr, INET6_ADDRSTRLEN))
    {
      len += snprintf(&netfile->line[len], NET_LINELEN - len,
                      "\tinet6 addr: %s/%d\n", addrstr, preflen);
    }

  return len;
}
#endif

/****************************************************************************
 * Name: netprocfs_inet6draddress
 ****************************************************************************/

#ifdef CONFIG_NET_IPv6
static int netprocfs_inet6draddress(FAR struct netprocfs_file_s *netfile)
{
  FAR struct net_driver_s *dev;
  char addrstr[INET6_ADDRSTRLEN];
  int len = 0;

  DEBUGASSERT(netfile != NULL && netfile->dev != NULL);
  dev = netfile->dev;

  /* Show the IPv6 default router address */

  if (inet_ntop(AF_INET6, dev->d_ipv6draddr, addrstr, INET6_ADDRSTRLEN))
    {
      len += snprintf(&netfile->line[len], NET_LINELEN - len,
                      "\tinet6 DRaddr: %s\n\n", addrstr);
    }

  return len;
}
#endif

/****************************************************************************
 * Name: netprocfs_blank_line
 ****************************************************************************/

#if !defined(CONFIG_NET_IPv4) && !defined(CONFIG_NET_IPv6)
static int netprocfs_blank_line(FAR struct netprocfs_file_s *netfile)
{
  netfile->line[0] = '\n';
  netfile->line[1] = '\0';
  return 1;
}
#endif

/****************************************************************************
 * Name: netprocfs_rxstatistics_header
 ****************************************************************************/

#ifdef CONFIG_NETDEV_STATISTICS
static int netprocfs_rxstatistics_header(
    FAR struct netprocfs_file_s *netfile)
{
  DEBUGASSERT(netfile != NULL);
  return snprintf(netfile->line, NET_LINELEN , "\tRX: %-8s %-8s %-8s %-8s\n",
                  "Received", "Fragment", "Errors", "Bytes");
}
#endif /* CONFIG_NETDEV_STATISTICS */

/****************************************************************************
 * Name: netprocfs_rxstatistics
 ****************************************************************************/

#ifdef CONFIG_NETDEV_STATISTICS
static int netprocfs_rxstatistics(FAR struct netprocfs_file_s *netfile)
{
  FAR struct netdev_statistics_s *stats;
  FAR struct net_driver_s *dev;

  DEBUGASSERT(netfile != NULL && netfile->dev != NULL);
  dev = netfile->dev;
  stats = &dev->d_statistics;

  return snprintf(netfile->line, NET_LINELEN, \
                  "\t    %08lx %08lx %08lx %-16llx\n",
                  (unsigned long)stats->rx_packets,
                  (unsigned long)stats->rx_fragments,
                  (unsigned long)stats->rx_errors,
                  (unsigned long long)stats->rx_bytes);
}
#endif /* CONFIG_NETDEV_STATISTICS */

/****************************************************************************
 * Name: netprocfs_rxpackets_header
 ****************************************************************************/

#ifdef CONFIG_NETDEV_STATISTICS
static int netprocfs_rxpackets_header(FAR struct netprocfs_file_s *netfile)
{
  FAR char *fmt;

  DEBUGASSERT(netfile != NULL);

  fmt = "\t    "
#ifdef CONFIG_NET_IPv4
        "%-8s "
#endif
#ifdef CONFIG_NET_IPv6
        "%-8s "
#endif
#ifdef CONFIG_NET_ARP
        "%-8s "
#endif
        "%-8s\n";

  return snprintf(netfile->line, NET_LINELEN, fmt
#ifdef CONFIG_NET_IPv4
        , "IPv4"
#endif
#ifdef CONFIG_NET_IPv6
        , "IPv6"
#endif
#ifdef CONFIG_NET_ARP
        , "ARP"
#endif
        , "Dropped");
}
#endif /* CONFIG_NETDEV_STATISTICS */

/****************************************************************************
 * Name: netprocfs_rxpackets
 ****************************************************************************/

#ifdef CONFIG_NETDEV_STATISTICS
static int netprocfs_rxpackets(FAR struct netprocfs_file_s *netfile)
{
  FAR struct netdev_statistics_s *stats;
  FAR struct net_driver_s *dev;
  FAR char *fmt;

  DEBUGASSERT(netfile != NULL && netfile->dev != NULL);
  dev = netfile->dev;
  stats = &dev->d_statistics;

  fmt = "\t    "
#ifdef CONFIG_NET_IPv4
        "%08lx "
#endif
#ifdef CONFIG_NET_IPv6
        "%08lx "
#endif
#ifdef CONFIG_NET_ARP
        "%08lx "
#endif
        "%08lx\n";

  return snprintf(netfile->line, NET_LINELEN, fmt
#ifdef CONFIG_NET_IPv4
        , (unsigned long)stats->rx_ipv4
#endif
#ifdef CONFIG_NET_IPv6
        , (unsigned long)stats->rx_ipv6
#endif
#ifdef CONFIG_NET_ARP
        , (unsigned long)stats->rx_arp
#endif
        , (unsigned long)stats->rx_dropped);
}
#endif /* CONFIG_NETDEV_STATISTICS */

/****************************************************************************
 * Name: netprocfs_txstatistics_header
 ****************************************************************************/

#ifdef CONFIG_NETDEV_STATISTICS
static int netprocfs_txstatistics_header(
    FAR struct netprocfs_file_s *netfile)
{
  DEBUGASSERT(netfile != NULL);

  return snprintf(netfile->line, NET_LINELEN,
                 "\tTX: %-8s %-8s %-8s %-8s %-8s\n",
                 "Queued", "Sent", "Errors", "Timeouts", "Bytes");
}
#endif /* CONFIG_NETDEV_STATISTICS */

/****************************************************************************
 * Name: netprocfs_txstatistics
 ****************************************************************************/

#ifdef CONFIG_NETDEV_STATISTICS
static int netprocfs_txstatistics(FAR struct netprocfs_file_s *netfile)
{
  FAR struct netdev_statistics_s *stats;
  FAR struct net_driver_s *dev;

  DEBUGASSERT(netfile != NULL && netfile->dev != NULL);
  dev = netfile->dev;
  stats = &dev->d_statistics;

  return snprintf(netfile->line, NET_LINELEN,
                  "\t    %08lx %08lx %08lx %08lx %-16llx \n",
                  (unsigned long)stats->tx_packets,
                  (unsigned long)stats->tx_done,
                  (unsigned long)stats->tx_errors,
                  (unsigned long)stats->tx_timeouts,
                  (unsigned long long)stats->tx_bytes);
}
#endif /* CONFIG_NETDEV_STATISTICS */

/****************************************************************************
 * Name: netprocfs_errors
 ****************************************************************************/

#ifdef CONFIG_NETDEV_STATISTICS
static int netprocfs_errors(FAR struct netprocfs_file_s *netfile)
{
  FAR struct netdev_statistics_s *stats;
  FAR struct net_driver_s *dev;

  DEBUGASSERT(netfile != NULL && netfile->dev != NULL);
  dev = netfile->dev;
  stats = &dev->d_statistics;

  return snprintf(netfile->line, NET_LINELEN,
                  "\tTotal Errors: %08" PRIx32 "\n\n",
                  stats->errors);
}
#endif /* CONFIG_NETDEV_STATISTICS */

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: netprocfs_read_devstats
 *
 * Description:
 *   Read and format network device statistics.
 *
 * Input Parameters:
 *   priv - A reference to the network procfs file structure
 *   buffer - The user-provided buffer into which device status will be
 *            returned.
 *   bulen  - The size in bytes of the user provided buffer.
 *
 * Returned Value:
 *   Zero (OK) is returned on success; a negated errno value is returned
 *   on failure.
 *
 ****************************************************************************/

ssize_t netprocfs_read_devstats(FAR struct netprocfs_file_s *priv,
                                FAR char *buffer, size_t buflen)
{
  return netprocfs_read_linegen(priv, buffer, buflen, g_netstat_linegen,
                                NSTAT_LINES);
}

#endif /* !CONFIG_DISABLE_MOUNTPOINT && CONFIG_FS_PROCFS &&
        * !CONFIG_FS_PROCFS_EXCLUDE_NET */