/* This file is part of Ingen.
 * Copyright (C) 2007-2009 Dave Robillard <http://drobilla.net>
 *
 * Ingen 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.
 *
 * Ingen 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 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.,
 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef INGEN_ENGINE_BUFFER_HPP
#define INGEN_ENGINE_BUFFER_HPP

#include <cstddef>
#include <cassert>
#include <boost/utility.hpp>
#include <boost/intrusive_ptr.hpp>
#include "raul/Deletable.hpp"
#include "raul/SharedPtr.hpp"
#include "interface/PortType.hpp"
#include "types.hpp"
#include "BufferFactory.hpp"

namespace Ingen {

class Context;
class Engine;
class BufferFactory;

class Buffer : public boost::noncopyable, public Raul::Deletable
{
public:
	Buffer(BufferFactory& factory, Shared::PortType type, size_t size)
		: _factory(factory)
		, _type(type)
		, _size(size)
		, _refs(0)
	{}

	/** Clear contents and reset state */
	virtual void clear() = 0;

	virtual void resize(size_t size) { _size = size; }

	virtual void*       port_data(Shared::PortType port_type) = 0;
	virtual const void* port_data(Shared::PortType port_type) const = 0;

	/** Rewind (ie reset read pointer), but leave contents unchanged */
	virtual void rewind() const {}

	virtual void copy(Context& context, const Buffer* src) = 0;

	virtual void prepare_read(Context& context) {}
	virtual void prepare_write(Context& context) {}

	Shared::PortType type() const { return _type; }
	size_t           size() const { return _size; }

	inline void ref() { ++_refs; }

	inline void deref() {
		assert(_refs > 0);
		if ((--_refs) == 0)
			_factory.recycle(this);
	}

protected:
	BufferFactory&   _factory;
	Shared::PortType _type;
	size_t           _size;

	friend class BufferFactory;
	virtual ~Buffer() {}

private:
	Buffer* _next; ///< Intrusive linked list for BufferFactory
	size_t  _refs; ///< Intrusive reference count for intrusive_ptr
};

} // namespace Ingen


namespace boost {
	inline void intrusive_ptr_add_ref(Ingen::Buffer* b) { b->ref(); }
	inline void intrusive_ptr_release(Ingen::Buffer* b) { b->deref(); }
}


#endif // INGEN_ENGINE_BUFFER_HPP