/********************************************************************
**                Image Component Library (ICL)                    **
**                                                                 **
** Copyright (C) 2006-2013 CITEC, University of Bielefeld          **
**                         Neuroinformatics Group                  **
** Website: www.iclcv.org and                                      **
**          http://opensource.cit-ec.de/projects/icl               **
**                                                                 **
** File   : ICLUtils/src/ICLUtils/CLBuffer.h                       **
** Module : ICLUtils                                               **
** Authors: Viktor Losing                                          **
**                                                                 **
**                                                                 **
** GNU LESSER GENERAL PUBLIC LICENSE                               **
** This file may be used under the terms of the GNU Lesser General **
** Public License version 3.0 as published by the                  **
**                                                                 **
** Free Software Foundation and appearing in the file LICENSE.GPL  **
** included in the packaging of this file.  Please review the      **
** following information to ensure the license requirements will   **
** be met: http://www.gnu.org/licenses/lgpl-3.0.txt                **
**                                                                 **
** The development of this software was supported by the           **
** Excellence Cluster EXC 277 Cognitive Interaction Technology.    **
** The Excellence Cluster EXC 277 is a grant of the Deutsche       **
** Forschungsgemeinschaft (DFG) in the context of the German       **
** Excellence Initiative.                                          **
**                                                                 **
********************************************************************/
#ifdef ICL_HAVE_OPENCL
#pragma once

#include <ICLUtils/CompatMacros.h>
#include <ICLUtils/CLException.h>
#include <ICLUtils/CLMemory.h>
#include <string>

/** \cond */
namespace cl{
  class Buffer;
  class Context;
  class CommandQueue;
}
/** \endcond */

namespace icl {
  namespace utils {
    
    /// Wrapper for an OpenCL Buffer
    /** Valid CLBuffer instances can only be created by a CLProgram instance.
        @see CLProgram for more details */
	class ICLUtils_API CLBuffer : public CLMemory {
      struct Impl; //!< internal hidden implementation type
      Impl *impl;  //!< internal implemetation
      
      /// private constructor (buffer can only be created by CLProgram instances)
      CLBuffer(cl::Context& context, cl::CommandQueue &cmdQueue, 
               const string &accessMode, size_t size, const void *src=NULL) throw (CLBufferException);
      
	  CLBuffer(cl::Context& context, cl::CommandQueue &cmdQueue, const string &accessMode,
			   size_t length, size_t byte_depth, const void *src=NULL) throw (CLBufferException);

      /// provides access to the underlying cl-buffer
      cl::Buffer &getBuffer();
      const cl::Buffer &getBuffer() const;

    public:
      friend class CLProgram; //!< for tight integration with CLProgram instances
      friend class CLKernel;  //!< for tight integration with CLKernel instances
	  friend class CLDeviceContext;//!< for tight integration with CLDeviceContext instances

      /// default constructor (creates null instance)
      CLBuffer();
      
      /// copy constructor (always performs shallow copy)
      CLBuffer(const CLBuffer& other);

      /// assignment operator (always performs a shallow copy)
      CLBuffer& operator=(const CLBuffer& other);

      /// destructor
      ~CLBuffer();
      
      /// copies the content of this buffer into the given buffer      
      void copy(CLBuffer &dst, int len, int src_offset = 0, int dst_offset = 0) throw (CLBufferException);
      
      /// reads buffer from graphics memory into given destination pointer
      void read(void *dst, int len, int offset = 0, bool block = true) throw (CLBufferException);
      
      /// writes source data into the graphics memory
      void write(const void *src, int len, int offset = 0, bool block = true) throw (CLBufferException);
      
      /// checks whether buffer is null
      bool isNull() const {
        return !impl;
      }
      
      /// checks whether buffer is not null
      operator bool() const {
        return impl;
      }
      
    };
  }
}
#endif