// -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*-
//
// Copyright (c) 2006 Georgia Tech Research Corporation
// All rights reserved.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License version 2 as
// published by the Free Software Foundation;
//
// This program 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 this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//
// Author: George F. Riley<riley@ece.gatech.edu>
//         Gustavo Carneiro <gjc@inescporto.pt>

#include "ipv4-static-routing.h"
#include "ns3/packet.h"


namespace ns3 {


void 
Ipv4StaticRouting::AddHostRouteTo (Ipv4Address dest, 
                                   Ipv4Address nextHop, 
                                   uint32_t interface)
{
  Ipv4Route *route = new Ipv4Route ();
  *route = Ipv4Route::CreateHostRouteTo (dest, nextHop, interface);
  m_hostRoutes.push_back (route);
}
void 
Ipv4StaticRouting::AddHostRouteTo (Ipv4Address dest, 
                                   uint32_t interface)
{
  Ipv4Route *route = new Ipv4Route ();
  *route = Ipv4Route::CreateHostRouteTo (dest, interface);
  m_hostRoutes.push_back (route);
}
void 
Ipv4StaticRouting::AddNetworkRouteTo (Ipv4Address network, 
                                      Ipv4Mask networkMask, 
                                      Ipv4Address nextHop, 
                                      uint32_t interface)
{
  Ipv4Route *route = new Ipv4Route ();
  *route = Ipv4Route::CreateNetworkRouteTo (network,
                                            networkMask,
                                            nextHop,
                                            interface);
  m_networkRoutes.push_back (route);
}
void 
Ipv4StaticRouting::AddNetworkRouteTo (Ipv4Address network, 
                                      Ipv4Mask networkMask, 
                                      uint32_t interface)
{
  Ipv4Route *route = new Ipv4Route ();
  *route = Ipv4Route::CreateNetworkRouteTo (network,
                                            networkMask,
                                            interface);
  m_networkRoutes.push_back (route);
}
void 
Ipv4StaticRouting::SetDefaultRoute (Ipv4Address nextHop, 
                                    uint32_t interface)
{
  Ipv4Route *route = new Ipv4Route ();
  *route = Ipv4Route::CreateDefaultRoute (nextHop, interface);
  delete m_defaultRoute;
  m_defaultRoute = route;
}

Ipv4Route *
Ipv4StaticRouting::LookupStatic (Ipv4Address dest)
{
  for (HostRoutesCI i = m_hostRoutes.begin (); 
       i != m_hostRoutes.end (); 
       i++) 
    {
      NS_ASSERT ((*i)->IsHost ());
      if ((*i)->GetDest ().IsEqual (dest)) 
        {
          return (*i);
        }
    }
  for (NetworkRoutesI j = m_networkRoutes.begin (); 
       j != m_networkRoutes.end (); 
       j++) 
    {
      NS_ASSERT ((*j)->IsNetwork ());
      Ipv4Mask mask = (*j)->GetDestNetworkMask ();
      Ipv4Address entry = (*j)->GetDestNetwork ();
      if (mask.IsMatch (dest, entry)) 
        {
          return (*j);
        }
    }
  if (m_defaultRoute != 0) 
    {
      NS_ASSERT (m_defaultRoute->IsDefault ());
      return m_defaultRoute;
    }
  return 0;
}

uint32_t 
Ipv4StaticRouting::GetNRoutes (void)
{
  uint32_t n = 0;
  if (m_defaultRoute != 0)
    {
      n++;
    }
  n += m_hostRoutes.size ();
  n += m_networkRoutes.size ();
  return n;
}
Ipv4Route *
Ipv4StaticRouting::GetRoute (uint32_t index)
{
  if (index == 0 && m_defaultRoute != 0)
    {
      return m_defaultRoute;
    }
  if (index > 0 && m_defaultRoute != 0)
    {
      index--;
    }
  if (index < m_hostRoutes.size ())
    {
      uint32_t tmp = 0;
      for (HostRoutesCI i = m_hostRoutes.begin (); 
           i != m_hostRoutes.end (); 
           i++) 
        {
          if (tmp  == index)
            {
              return *i;
            }
          tmp++;
        }
    }
  index -= m_hostRoutes.size ();
  uint32_t tmp = 0;
  for (NetworkRoutesI j = m_networkRoutes.begin (); 
       j != m_networkRoutes.end (); 
       j++) 
    {
      if (tmp == index)
        {
          return *j;
        }
      tmp++;
    }
  NS_ASSERT (false);
  // quiet compiler.
  return 0;
}
void 
Ipv4StaticRouting::RemoveRoute (uint32_t index)
{
  if (index == 0 && m_defaultRoute != 0)
    {
      delete m_defaultRoute;
      m_defaultRoute = 0;
    }
  if (index > 0 && m_defaultRoute != 0)
    {
      index--;
    }
  if (index < m_hostRoutes.size ())
    {
      uint32_t tmp = 0;
      for (HostRoutesI i = m_hostRoutes.begin (); 
           i != m_hostRoutes.end (); 
           i++) 
        {
          if (tmp  == index)
            {
              delete *i;
              m_hostRoutes.erase (i);
              return;
            }
          tmp++;
        }
    }
  index -= m_hostRoutes.size ();
  uint32_t tmp = 0;
  for (NetworkRoutesI j = m_networkRoutes.begin (); 
       j != m_networkRoutes.end (); 
       j++) 
    {
      if (tmp == index)
        {
          delete *j;
          m_networkRoutes.erase (j);
          return;
        }
      tmp++;
    }
  NS_ASSERT (false);
}

bool
Ipv4StaticRouting::RequestRoute (Ipv4Header const &ipHeader,
                                 Packet packet,
                                 RouteReplyCallback routeReply)
{
  Ipv4Route *route = LookupStatic (ipHeader.GetDestination ());
  if (route != 0)
    {
      routeReply (true, *route, packet, ipHeader);
      return true;
    }
  else
    {
      return false; // Let other routing protocols try to handle this
                    // route request.
    }
}

void
Ipv4StaticRouting::DoDispose (void)
{
  for (HostRoutesI i = m_hostRoutes.begin (); 
       i != m_hostRoutes.end (); 
       i = m_hostRoutes.erase (i)) 
    {
      delete (*i);
    }
  for (NetworkRoutesI j = m_networkRoutes.begin (); 
       j != m_networkRoutes.end (); 
       j = m_networkRoutes.erase (j)) 
    {
      delete (*j);
    }
  if (m_defaultRoute != 0)
    {
      delete m_defaultRoute;
      m_defaultRoute = 0;
    }
  Ipv4RoutingProtocol::DoDispose ();
}


}//namespace ns3