/*
  OutputSlot  -  capability to transfer data to a physical output

  Copyright (C)         Lumiera.org
    2011,               Hermann Vosseler <Ichthyostega@web.de>

  This program 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 2 of
  the License, or (at your option) any later version.

  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., 675 Mass Ave, Cambridge, MA 02139, USA.

* *****************************************************/


#include "lib/error.hpp"
#include "proc/play/output-slot.hpp"
#include "proc/play/output-slot-connection.hpp"

#include <boost/noncopyable.hpp>
#include <vector>


namespace proc {
namespace play {
  
  using std::vector;
  
  namespace error = lumiera::error;
  
  
  
  namespace { // hidden local details of the service implementation....
    
  } // (End) hidden service impl details
  
  
  
  
  
  
  OutputSlot::~OutputSlot() { }  // emit VTables here....
  
  OutputSlot::Allocation::~Allocation() { }
  
  OutputSlot::Connection::~Connection() { }
  
  
  
  
  
  /** whether this output slot is occupied
   * @return true if currently unconnected and
   *         able to connect and handle output data 
   */
  bool
  OutputSlot::isFree()  const
  {
    return ! this->state_;
  }
  
  
  /** */
  OutputSlot::Allocation&
  OutputSlot::allocate()
  {
    if (!isFree())
      throw error::Logic ("Attempt to open/allocate an OutputSlot already in use.");
    
    UNIMPLEMENTED ("internal interface to determine the number of channel-connections");
    
    state_.reset (this->buildState());
    return *state_;
  }
  
  
  void
  OutputSlot::disconnect()
  {
    if (!isFree())
      state_.reset(0);    
  }
  
  
  
  /* === DataSink frontend === */
  
  BuffHandle
  DataSink::lockBufferFor(FrameID frameNr)
  {
    return impl().claimBufferFor(frameNr);
  }
  
  
  void
  DataSink::emit (FrameID frameNr, BuffHandle const& data2emit, TimeValue currentTime)
  {
    OutputSlot::Connection& connection = impl();
    if (connection.isTimely(frameNr,currentTime))
      connection.transfer(data2emit);
    else
      connection.discard(data2emit);
  }
  

  
  
  
}} // namespace proc::play