nodered.c

/*
 * Copyright (c) 2022-2023  Moddable Tech, Inc.
 *
 *   This file is part of the Moddable SDK Runtime.
 *
 *   The Moddable SDK Runtime is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   The Moddable SDK Runtime 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 Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with the Moddable SDK Runtime.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include "xsmc.h"

#include "xsHost.h"

// 16 byte string. random hex values.
void xs_nodered_util_generateId(xsMachine *the)
{
	char id[16];
	size_t i;
	static const char hex[] = "0123456789abcdef";

	for (i = 0; i < sizeof(id); i+= 4) {
		int r = c_rand();
		id[i + 0] = hex[r & 0x0f];
		id[i + 1] = hex[(r >> 4) & 0x0f];
		id[i + 2] = hex[(r >> 8) & 0x0f];
		id[i + 3] = hex[(r >> 12) & 0x0f];
	}

	xsmcSetStringBuffer(xsResult, id, sizeof(id));
}

void xs_nodered_util_debugging(xsMachine *the)
{
#ifdef mxDebug
	extern xsBooleanValue fxIsConnected(xsMachine* the);
	xsmcSetBoolean(xsResult, fxIsConnected(the));
#endif
}

void xs_buffer_prototype_indexOf(xsMachine *the)
{
	int offset = 0;
	uint8_t *needle, *haystack, *initialHaystack;
	xsUnsignedValue needleLength, haystackLength;

	if (xsmcArgc > 1) {
		offset = xsmcToInteger(xsArg(1));
		if (xsmcArgc > 2)
			xsUnknownError("unsupported");
	}

	if (xsReferenceType != xsmcTypeOf(xsArg(0)))
		xsUnknownError("unsupported");		// valid to pass string or number for arg(0)

	xsmcGetBufferReadable(xsArg(0), (void **)&needle, &needleLength);
	xsmcGetBufferReadable(xsThis, (void **)&haystack, &haystackLength);
	initialHaystack = haystack;

	if (0 == offset)
		;
	else if ((offset < 0) && (-offset < (int)haystackLength)) {
		haystack += haystackLength + offset;
		haystackLength = -offset;
	}
	else if ((offset > 0) && (offset < (int)haystackLength)) {
		haystack += offset;
		haystackLength -= offset;
	}
	else
		xsUnknownError("invalid offset");

	if (needleLength <= haystackLength) {
		uint8_t *lastHaystack = haystack + haystackLength - needleLength;
		for ( ; haystack <= lastHaystack; haystack++) {
			if (0 == c_memcmp(haystack, needle, needleLength)) {
				xsmcSetInteger(xsResult, haystack - initialHaystack);
				return;
			}
		}
	}

	xsmcSetInteger(xsResult, -1);
}

void xs_buffer_prototype_lastIndexOf(xsMachine *the)
{
	int offset;
	uint8_t *needle, *haystack, *initialHaystack;
	xsUnsignedValue needleLength, haystackLength;

	if (xsmcArgc > 1) {
		offset = xsmcToInteger(xsArg(1));
		if (xsmcArgc > 2)
			xsUnknownError("unsupported");
	}

	if (xsReferenceType != xsmcTypeOf(xsArg(0)))
		xsUnknownError("unsupported");		// valid to pass string or number for arg(0)

	xsmcGetBufferReadable(xsArg(0), (void **)&needle, &needleLength);
	xsmcGetBufferReadable(xsThis, (void **)&haystack, &haystackLength);
	initialHaystack = haystack;
	
	if (xsmcArgc < 2)
		haystack = initialHaystack + haystackLength - 1; 
	else if (0 == offset)
		;
	else if ((offset < 0) && (-offset < (int)haystackLength)) {
		haystack += haystackLength + offset;
	}
	else if ((offset > 0) && (offset < (int)haystackLength)) {
		haystack += offset;
	}
	else
		xsUnknownError("invalid offset");

	if (needleLength <= haystackLength) {
		if ((haystack + needleLength) > (initialHaystack + haystackLength))
			haystack = initialHaystack + haystackLength - needleLength; 
		for ( ; haystack >= initialHaystack; haystack--) {
			if (0 == c_memcmp(haystack, needle, needleLength)) {
				xsmcSetInteger(xsResult, haystack - initialHaystack);
				return;
			}
		}
	}

	xsmcSetInteger(xsResult, -1);
}