#' QGIS-i algoritmi leidmine fraasi järele
#'
#' Funktsioon leiab fraasi järele QGIS-i algoritmid.
#' @param str	string otsitav algoritmi fraas.
#' @return Table found algorithms. Help for the selected algorithm.
#' @return A array of all database schemas.
#' @seealso [qgisprocess::qgis_algorithms()]
#' @keywords qgis, help
#' @export
#' @examples
#' \dontrun{
#'
#' qgis_algorithm_search_by_word(str = "clip")
#' algorithm <- "native:clip"
#' # Read help.
#' ruut::qgis_show_help(algorithm = algorithm)
#'
#' qgis_algorithm_search_by_word(str = "centroid")
#' qgis_algorithm_search_by_word(str = "filedownloader")
#' qgis_algorithm_search_by_word(str = "")
#' qgis_algorithm_search_by_word()
#' }
qgis_algorithm_search_by_word <- function(str = NULL) {
  if (is.null(str) || str == "") {
    return(NULL)
  }
  x <- system(sprintf("qgis_process list | grep %s", str), intern = TRUE)
  x <- do.call("rbind", strsplit(x, "\t"))[, 2:3]
  cat("\n----------------\n")
  x
}