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

#include "apl9.h"

Rune primmonopnames[] = L"¨⍨⌸⌶&";
Rune primdyadopnames[] = L"⍣.∘⍤⍥@⍠⌺";

opmonad monadoperatordefs[] = {
	opEach, /* ¨ */
	opSwitch, /* ⍨ */
	0, /* ⌸ */
	0, /* ⌶ */
	0, /* & */
};

opdyad dyadoperatordefs[] = {
	0, /* ⍣ */
	0, /* . */
	opBind, /* ∘ */
	0, /* ⍤ */
	opOver, /* ⍥ */
	0, /* @ */
	0, /* ⍠ */
	0, /* ⌺ */
};

/* Monadic operators */
Array *
opEach(Datum *lefto, Array *left, Array *right)
{
	int i;
	if(lefto->tag != FunctionTag)
		return nil;
	Array *leftarr;
	Array *rightarr;
	if(left){
		int rankok = scalarextend(left, right, &leftarr, &rightarr);
		if(!rankok)
			throwerror(nil, ERank);
	}else{
		leftarr = nil;
		rightarr = fnSame(right);
	}

	Array *result = allocarray(AtypeArray, rightarr->rank, rightarr->size);
	for(i = 0; i < rightarr->rank; i++)
		result->shape[i] = rightarr->shape[i];
	for(i = 0; i < rightarr->size; i++){
		Array *elem1 = leftarr ? arrayitem(leftarr, i) : nil;
		Array *elem2 = arrayitem(rightarr, i);
		result->arraydata[i] = runfunc(lefto->func, elem1, elem2);
		freearray(elem1);
		freearray(elem2);
	}
	freearray(leftarr);
	freearray(rightarr);
	return result;
}

Array *
opSwitch(Datum *lefto, Array *left, Array *right)
{
	if(lefto->tag == ArrayTag){
		incref(lefto->array);
		return lefto->array;
	}else if(lefto->tag == FunctionTag){
		if(left)
			return runfunc(lefto->func, right, left);
		else
			return runfunc(lefto->func, right, right);
	}else
		return nil;
}

/* Dyadic operators */
Array *
opBind(Datum *lefto, Datum *righto, Array *left, Array *right)
{
	if(lefto->tag == FunctionTag && righto->tag == FunctionTag){
		Array *right1 = runfunc(righto->func, nil, right);
		Array *result = runfunc(lefto->func, left, right1);
		freearray(right1);
		return result;
	}else if(lefto->tag == FunctionTag && righto->tag == ArrayTag){
		if(left)
			throwerror(L"The function doesn't take a left argument", ESyntax);
		return runfunc(lefto->func, right, righto->array);
	}else if(lefto->tag == ArrayTag && righto->tag == FunctionTag){
		if(left)
			throwerror(L"The function doesn't take a left argument", ESyntax);
		return runfunc(righto->func, lefto->array, right);
	}else
		return nil;
}

Array *
opOver(Datum *lefto, Datum *righto, Array *left, Array *right)
{
	if(lefto->tag != FunctionTag || righto->tag != FunctionTag)
		return nil;
	if(left){
		Array *r = runfunc(righto->func, nil, right);
		Array *l = runfunc(righto->func, nil, left);
		Array *res = runfunc(lefto->func, l, r);
		freearray(r);
		freearray(l);
		return res;
	}else{
		Array *tmp = runfunc(righto->func, nil, right);
		Array *res = runfunc(lefto->func, nil, tmp);
		freearray(tmp);
		return res;
	}
}