// Emacs: -*- C++ -*-

//
//	Copyright 1993, Center for Computer Vision and Visualization,
//	University of Florida.  All rights reserved.
//


//
// $Log: img-templ-product,v $
// Revision 1.10  1994/07/25  17:26:39  thoth
// Name sanitization
//
// Revision 1.9  1994/03/30  14:01:44  thoth
// zero_extension is now a template function.
//
// Revision 1.8  1994/03/14  15:53:13  thoth
// We now use the FBI to extract the baseptr.
//
// Revision 1.7  1994/02/22  18:49:39  thoth
// We now efficiently evaluate lazy template-template convolutions
// convolved with images.
//
// Revision 1.6  1994/02/12  19:45:43  thoth
// Forward and Backward convolutions are now specified separately.
//
// Revision 1.5  1994/01/31  15:50:18  thoth
// fixed typing error in invariant convolutions.
//
// Revision 1.4  1994/01/07  15:10:00  thoth
// Image class is now CoreImage and named image types are
// Image<P,T>.
//
// Revision 1.3  1993/12/29  17:33:18  thoth
// New operator scheme that prevents the need for trivial Image conversions.
//
// Revision 1.2  1993/11/17  18:29:46  thoth
// We now have support for forward convolutions.
// IPSIter is now PSIter<IntPoint>.
//
// Revision 1.1  1993/09/15  13:02:08  thoth
// Initial revision
//
// Revision 1.5  93/05/27  11:48:55  thoth
// Copyright Notices
// 
// Revision 1.4  93/04/29  11:20:56  thoth
// Faster(?) extension for VectorDIs.
// 
// Revision 1.3  93/04/17  18:56:44  jnw
// Fixed to match IA_Point<int> membername (dim)
// 
// Revision 1.2  93/04/08  13:21:59  thoth
// internal helper functions are now static.
// 
// Revision 1.1  93/03/18  11:39:42  thoth
// Initial revision
// 

//
// backward convolutions
//

static IA_Image<IA_Point<int>,RTYPE>
backw_CONV_inv_core(IA_Point<int> src_infimum,
	      IA_Point<int> src_width,
	      const IBTYPE *src_data, // length is prod(src_width)
	      const IA_Image<IA_Point<int>,TBTYPE> &templ,
	      IA_Set<IA_Point<int> > dest_ps)
{
    const int	dimen = src_width.dim();

    IA_Set<IA_Point<int> >	templ_ps = templ.domain();
    int		templ_sz = templ_ps.card();
    TBTYPE	*const templ_data = new TBTYPE[templ_sz];
    int	*const templ_offsets = new int[templ_sz];

    {
	TBTYPE	*d_scan = templ_data;
	int	*o_scan = templ_offsets;
	IA_IPIter<IA_Point<int>,TBTYPE>	iter(templ);
	IA_Point<int>	ip;
	while (iter(ip, *d_scan)) {
	    *o_scan = ip[0];
	    for (unsigned i=1; i<dimen; i++) {
		*o_scan *= src_width[i];
		*o_scan += ip[i];
	    }
	    d_scan++;
	    o_scan++;
	}
    }

    IA_PSIter<IA_Point<int> >	iter(dest_ps);
    IA_Point<int>	ip;
    RTYPE *const	dest_data = new RTYPE[dest_ps.card()];
    RTYPE *	valp = dest_data;
    while (iter(ip)) {
	int	offset= ip[0] - src_infimum[0];
	unsigned i;
	for (i=1; i<dimen; i++) {
	    offset *= src_width[i];
	    offset += ip[i] - src_infimum[i];
	}
	const IBTYPE *const base = src_data + offset;

	// _IVAL_=(base[templ_offsets[i]])
	// _TVAL_=(templ_data[i])
	// _IRESULT_=(*valp)

	INITIALIZE ;

	for (i=0; i<templ_sz; i++) {
	    ACCUMULATE ;
	}
	{
	    RESULT ;
	}
	valp++;
    }
    delete[] templ_offsets;
    delete[] templ_data;

    return IA_Image<IA_Point<int>,RTYPE>(dest_ps, dest_data, dest_ps.card(), 1);
}

static IA_Image<IA_Point<int>,RTYPE>
backw_CONV_inv(const IA_Image<IA_Point<int>,IBTYPE> &img,
	 const IA_Image<IA_Point<int>,TBTYPE> &invtempl,
	 IA_Set<IA_Point<int> > dest_ps)
{
    IA_Point<int>	inf_ = dest_ps.inf()+invtempl.domain().inf();
    IA_Point<int>	sup_ = dest_ps.sup()+invtempl.domain().sup();
    IA_Set<IA_Point<int> >	src_ps = IA_Set<IA_Point<int> >(inf_,sup_);

    IBTYPE	*const src_data = new IBTYPE[src_ps.card()];

    zero_extend(img, src_ps, (IBTYPE*)src_data, IBTYPE(ZERO));
    IA_Image<IA_Point<int>,RTYPE>	rval =
	backw_CONV_inv_core(inf_, sup_-inf_ + 1, src_data, invtempl, dest_ps);

    delete[] src_data;

    return rval;
}

IA_Image<IA_Point<int>,RTYPE>
CONV(const IA_CoreImage<IA_Point<int>,IBTYPE> &img_,
     const IA_DDTemplate<TITYPE > &templ_,
     IA_Set<IA_Point<int> > dest_ps)
{
    IA_Image<IA_Point<int>,IBTYPE>	img(img_);
    /*PROMOTE*/IA_DDTemplate<TITYPE >	templ(templ_);

#ifdef KNOWN_IA_lazy_CONV_RTYPE
    if (templ.is_a(IA_lazy_inv_CONV_RTYPE::s_type())) {
	const IA_lazy_inv_CONV_RTYPE	*t =
	    (const IA_lazy_inv_CONV_RTYPE *)IA_FBI<IA_Point<int>, IA_Point<int>, IBTYPE, IBTYPE, IBTYPE>::extract_baseptr(templ);
	IA_Set<IA_Point<int> >	bigger_ps(
	    IA_Point<int>(dest_ps.inf()+
			(t->rhs(extend_to_point(0, t->rhs.domain().dim()))
			 .domain().inf())),
	    IA_Point<int>(dest_ps.sup()+
			(t->rhs(extend_to_point(0, t->rhs.domain().dim()))
			 .domain().sup())),
	    );
	return CONV(CONV(img, t->lhs, bigger_ps), t->rhs, dest_ps);
    } else
#else
#define UNKNOWN_IA_lazy_CONV_RTYPE
#endif
	if (templ.is_a(IA_InvariantDT<TITYPE >::s_type())) {
	return backw_CONV_inv
	    (img, ((IA_InvariantDT<TITYPE >*)IA_FBI<IA_Point<int>, IA_Point<int>, IBTYPE, IBTYPE, TBTYPE>::extract_baseptr(templ))->value, dest_ps);
//    } else if (templ.type() == IA_Lazy_REDUCT_DT<TITYPE >::s_type()) {
    } else {
	RTYPE *const	dest_data = new RTYPE[dest_ps.card()];
	RTYPE	*valp = dest_data;
	IA_PSIter<IA_Point<int> >	dest_iter(dest_ps);
	IA_Point<int>	base_ip;
	while (dest_iter(base_ip)) {
	    IA_CoreImage<IA_Point<int>,TBTYPE>	tv = templ(base_ip);

	    IA_IPIter<IA_Point<int>,TBTYPE>	templ_iter(tv);
	    IA_Point<int>	templ_ip;
	    TBTYPE	templ_val;

	    // _IVAL_=img(ip)
	    // _TVAL_=templ_val
	    // _IRESULT_=(*valp)

	    INITIALIZE ;

	    while ( templ_iter(templ_ip, templ_val) ) {
		const IA_Point<int>	ip = templ_ip; //+base_ip;
		if (! img.domain().contains(ip))
		    continue;
		ACCUMULATEVAR ;
	    }
	    {
		RESULT ;
	    }
	    valp++;
	}
	return IA_Image<IA_Point<int>,RTYPE>(dest_ps, dest_data,
					   dest_ps.card(), 1);
    }
}
