/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

#include "ns3/object.h"
#include "ns3/ptr.h"
#include "ns3/log.h"
#include "ns3/enum.h"

#include "leo-mock-net-device.h"
#include "leo-mock-channel.h"

namespace ns3 {

NS_LOG_COMPONENT_DEFINE ("LeoMockChannel");

NS_OBJECT_ENSURE_REGISTERED (LeoMockChannel);

TypeId
LeoMockChannel::GetTypeId (void)
{
  static TypeId tid = TypeId ("ns3::LeoMockChannel")
    .SetParent<MockChannel> ()
    .SetGroupName ("Leo")
    .AddConstructor<LeoMockChannel> ()
  ;
  return tid;
}

LeoMockChannel::LeoMockChannel() :
  MockChannel ()
{
  NS_LOG_FUNCTION_NOARGS ();
}

LeoMockChannel::~LeoMockChannel()
{
}

bool
LeoMockChannel::TransmitStart (Ptr<const Packet> p,
               		       uint32_t devId,
               		       Address dst,
               		       Time txTime)
{
  // Find devices joined to channel
  Ptr<MockNetDevice> srcDev = DynamicCast<MockNetDevice> (GetDevice (devId));

  bool isBroadcast = (srcDev->GetBroadcast () == dst);
  bool toSatellite = m_groundDevices.find (srcDev->GetAddress ()) != m_groundDevices.end ();

  if (isBroadcast)
    {
      // Broadcast hack for ARP and neighbor cache
      // TODO remove if found a way to fill neighbor cache / ARP by hand
      for (uint32_t i = 0; i < GetNDevices (); i++)
    	{
      	  // TODO deliver only to devices in the same beam
      	  Deliver (p, srcDev, DynamicCast<MockNetDevice> (GetDevice (i)), txTime);
    	}
    }
  else
    {
      if (toSatellite)
      	{
      	  // Satellites can always directly be addresses
      	  // Assume beams are narrow enough to not also receive the signal at other
      	  // satellites for performance reasons.
      	  DeviceIndex::iterator it = m_satelliteDevices.find (dst);
      	  if (it == m_satelliteDevices.end ())
      	    {
      	      NS_LOG_LOGIC (this << "unable to find satellite with address " << dst);
      	      return false;
      	    }
      	  Deliver (p, srcDev, it->second, txTime);
      	}
      else
      	// space to ground delivers to everything within the beam
      	{
      	  for (DeviceIndex::iterator it = m_groundDevices.begin ();
       	       it != m_groundDevices.end ();
       	       it++)
    	    {
      	      // TODO deliver only to devices in the same beam
      	      Deliver (p, srcDev, it->second, txTime);
    	    }
      	}
    }

  return true;
}

int32_t
LeoMockChannel::Attach (Ptr<MockNetDevice> device)
{
  Ptr<LeoMockNetDevice> leodev = DynamicCast<LeoMockNetDevice> (device);

  // Add to index
  switch (leodev->GetDeviceType ())
    {
    case LeoMockNetDevice::DeviceType::GND:
      m_groundDevices[leodev->GetAddress ()] = leodev;
      break;
    case LeoMockNetDevice::DeviceType::SAT:
      m_satelliteDevices[leodev->GetAddress ()] = leodev;
      break;
    default:
      break;
    }

  return MockChannel::Attach (device);
}

bool
LeoMockChannel::Detach (uint32_t deviceId)
{
  Ptr<NetDevice> dev = GetDevice (deviceId);
  m_groundDevices.erase (dev->GetAddress ());
  m_satelliteDevices.erase (dev->GetAddress ());

  return MockChannel::Detach (deviceId);
}

}; // namespace ns3