Method findSubstring

src/csvtable.cpp:272–338

* Searches for substring starting at the next cell from (myRow, myCol). * Returns (row,col) if found, (-1,-1) if not */

 *	Returns (row,col) if found, (-1,-1) if not
 */
std::tuple<table_index_t, table_index_t> CsvTable::findSubstring(std::string search, table_index_t startRow, table_index_t startCol, std::vector<table_index_t> sel, bool caseSensitive, bool useRegex) {
	table_index_t r;
	table_index_t c;
	int cnt;						// `cnt` is used to avoid endless loops in do-while below
	table_index_t searchAreaSize;
	std::string lowerSearch;
	std::string status;
	searchArea = sel;
	searchAreaSize = (sel[2]-sel[0]+1) * (sel[3]-sel[1]+1);
	std::tuple<table_index_t, std::string> executeReturn;				// for JS search
	
	//
	// if a Regex search, use JS 
	//
	if( useRegex ) {
		std::string js = createJsFindSubstring(search, startRow, startCol, caseSensitive);
		executeReturn = macro.execute(this, {sel[0],sel[1],sel[2],sel[3]}, js);
		// if( std::get<0>(executeReturn) == -1 ) {
		// 	printf("ERROR: %s\n", std::get<1>(executeReturn).c_str());
		// }
		std::vector<int> result = Macro::getLastResultInts();
		if( result.size() == 2 ) {
			return std::make_tuple(result[0], result[1]);
		}
		return std::make_tuple(-1, -1);
	}

	if( !caseSensitive ) {
		lowerSearch = Utf8CppUtils::utf8::casefold(search);
	}
	
	r = startRow;
	c = startCol;
	// step over to first cell within `searchArea`
	cnt = 0;
	do {
		std::tie(r,c) = nextField(r,c);
		++cnt;
	} while( (r < searchArea[0] || r > searchArea[2] || c < searchArea[1] || c > searchArea[3]) && cnt <= searchAreaSize );
	startRow = r;
	startCol = c;
	// start searching ...
	cnt = 0;
	// TODO Avoid multiple searches in the same row (to improve performance)
	do {
		if( caseSensitive ) {
			if(
				storage.getRow(r).find(search) != std::string::npos &&		// first search in rows – only if matching, search in cell
				getCell(r,c).find(search) != std::string::npos
			) {
				return std::make_tuple(r, c);
			}
		} else {
			if(
				Utf8CppUtils::utf8::casefold(storage.getRow(r)).find(lowerSearch) != std::string::npos &&
				Utf8CppUtils::utf8::casefold(getCell(r,c)).find(lowerSearch) != std::string::npos
			) {
				return std::make_tuple(r, c);