#include <u.h>
#include <libc.h>
#include <bio.h>

#include "apl9.h"

int datasizes[] = {
	[AtypeInt] = sizeof(vlong),
	[AtypeArray] = sizeof(Array *)
};

Array *
mkscalarint(vlong i)
{
	Array *a = allocarray(AtypeInt, 0, 1);
	a->intdata[0] = i;

	return a;
}

Array *
duparray(Array *a)
{
	Array *b = allocarray(a->type, a->rank, a->size);
	memcpy(b->shape, a->shape, sizeof(int) * a->rank);
	memcpy(b->rawdata, a->rawdata, datasizes[a->type]*a->size);
	if(b->type == AtypeArray)
		for(int i = 0; i < b->size; i++)
			incref(b->arraydata[i]);
	return b;
}

int
simplearray(Array *a)
{
	return a->type != AtypeArray;
}

int
simplescalar(Array *a)
{
	return simplearray(a) && a->rank == 0;
}

Array *
extend(Array *a, Array *b)
{
	/* extend the singleton a to the shape of b */
	Array *shape = fnShape(b);
	Array *res = fnReshape(shape, a);
	freearray(shape);
	return res;
}

int
scalarextend(Array *a, Array *b, Array **aa, Array **bb)
{
	/* Extend the arrays a and b to have the same shape.
	   The resulting arrays are stored in aa and bb,
	   except when the ranks don't match or extension can't
	   happen, in which case the function returns 0 and
	   aa and bb are unchanged.
	*/

	if(a->size == 1 && b->size != 1){
		*aa = extend(a, b);
		*bb = fnSame(b);
	}else if(b->size == 1 && a->size != 1){
		*aa = fnSame(a);
		*bb = extend(b, a);
	}else if(a->size == b->size && a->rank == b->rank){
		/* Check that each dimension matches */
		for(int i = 0; i < a->rank; i++)
			if(a->shape[i] != b->shape[i])
				return 0;
		*aa = fnSame(a);
		*bb = fnSame(b);
	}else
		return 0;
	return 1;
}