R/zzz.R

In giswqs/whiteboxR: 'WhiteboxTools' R Frontend

.onLoad <- function(libname, pkgname) {
  # check_whitebox_binary() is called "loudly" only on package load either:
  #   1. interactively, or 
  #   2. environment var R_WHITEBOX_VERBOSE=TRUE or package option whitebox.verbose=TRUE
  check_whitebox_binary(silent = !wbt_verbose())
  
  # keep track of whether we have warned about version difference
  assign("whitebox.warned_version_difference", value = FALSE, envir = whitebox.env)
}

#' Check for 'WhiteboxTools' executable path
#'
#' @param silent logical. Print help on installation/setting path. Default `TRUE`.
#' @seealso [wbt_exe_path()]
#' @return logical if 'WhiteboxTools' executable file exists.
#' @export
#' @keywords General
check_whitebox_binary <- function(silent = TRUE) {

  # look in standard locations
  exe_path <- wbt_exe_path(shell_quote = FALSE)
  res <- file.exists(exe_path)

  if (!res && !silent) {
    msg <- paste0(
      "\n",
      "------------------------------------------------------------------------\n",
      "Could not find WhiteboxTools!\n",
      "------------------------------------------------------------------------\n",
      "\n",
      "Your next step is to download and install the WhiteboxTools binary:\n",
      "    > whitebox::install_whitebox()\n",
      "\n",
      "If you have WhiteboxTools installed already run `wbt_init(exe_path=...)`': \n",
      "    > wbt_init(exe_path='/home/user/path/to/whitebox_tools')\n",
      "\n",
      "For whitebox package documentation, ask for help:\n",
      "    > ??whitebox\n",
      "\n",
      "For more information visit https://whiteboxR.gishub.org/\n",
      "\n",
      "------------------------------------------------------------------------\n")
    message(msg)
  }
  res
}