/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * Copyright (c) 2007 The Zdeno Ash Miklas
 *
 * This source file is part of VideoTexture library
 *
 * Contributor(s):
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file FilterBase.h
 *  \ingroup bgevideotex
 */

#ifndef __FILTERBASE_H__
#define __FILTERBASE_H__

#include "Common.h"

#include "PyObjectPlus.h"

#include "PyTypeList.h"

#define VT_C(v,idx)	((unsigned char*)&v)[idx]
#define VT_R(v)	((unsigned char*)&v)[0]
#define VT_G(v)	((unsigned char*)&v)[1]
#define VT_B(v)	((unsigned char*)&v)[2]
#define VT_A(v)	((unsigned char*)&v)[3]
#define VT_RGBA(v,r,g,b,a)	VT_R(v)=(unsigned char)r, VT_G(v)=(unsigned char)g, VT_B(v)=(unsigned char)b, VT_A(v)=(unsigned char)a

// forward declaration
class FilterBase;


// python structure for filter
struct PyFilter
{
	PyObject_HEAD
	// source object
	FilterBase * m_filter;
};


/// base class for pixel filters
class FilterBase
{
public:
	/// constructor
	FilterBase (void);
	/// destructor
	virtual ~FilterBase (void);
	// release python objects
	virtual void release (void);

	/// convert pixel
	template <class SRC> unsigned int convert (SRC src, short x, short y,
		short * size, unsigned int pixSize)
	{
		return filter(src, x, y, size, pixSize,
			convertPrevious(src, x, y, size, pixSize));
	}

	/// get previous filter
	PyFilter * getPrevious (void) { return m_previous; }
	/// set previous filter
	void setPrevious (PyFilter *filt, bool useRefCnt = true);

	/// find first filter in chain
	FilterBase * findFirst (void);

	/// get first filter's source pixel size
	unsigned int firstPixelSize (void) { return findFirst()->getPixelSize(); }

protected:
	/// previous pixel filter
	PyFilter * m_previous;

	/// filter pixel, source byte buffer
	virtual unsigned int filter(unsigned char *src, short x, short y,
	                            short *size, unsigned int pixSize, unsigned int val = 0)
	{ return val; }
	/// filter pixel, source int buffer
	virtual unsigned int filter(unsigned int *src, short x, short y,
	                            short *size, unsigned int pixSize, unsigned int val = 0)
	{ return val; }
	/// filter pixel, source float buffer
	virtual unsigned int filter(float *src, short x, short y,
	                            short *size, unsigned int pixSize, unsigned int val = 0)
	{ return val; }

	/// get source pixel size
	virtual unsigned int getPixelSize(void) { return 1; }

	/// get converted pixel from previous filters
	template <class SRC> unsigned int convertPrevious (SRC src, short x, short y,
		short * size, unsigned int pixSize)
	{
		// if previous filter doesn't exists, return source pixel
		if (m_previous == NULL) return *src;
		// otherwise return converted pixel
		return m_previous->m_filter->convert(src, x, y, size, pixSize);
	}
};


// list of python filter types
extern PyTypeList pyFilterTypes;


// functions for python interface

// object initialization
template <class T> static int Filter_init (PyObject *pySelf, PyObject *args, PyObject *kwds)
{
	PyFilter *self = reinterpret_cast<PyFilter*>(pySelf);
	// create filter object
	if (self->m_filter != NULL) delete self->m_filter;
	self->m_filter = new T();
	// initialization succeded
	return 0;
}

// object allocation
PyObject *Filter_allocNew(PyTypeObject *type, PyObject *args, PyObject *kwds);
// object deallocation
void Filter_dealloc(PyFilter *self);

// get previous pixel filter object
PyObject *Filter_getPrevious(PyFilter *self, void *closure);
// set previous pixel filter object
int Filter_setPrevious(PyFilter *self, PyObject *value, void *closure);


#endif