R/set_path_to_tiger.R

In GL-Li/ggtiger: Draw and fill in TIGER boundaries on ggmap

#' Set path to directory storing processed TIGER data
#'
#'
#' @param path path to directory holding all downloaded and converted TIGER data, such as
#'     "E:/my_tiger_data" and "~/tiger_data".
#'
#' @export

set_path_to_tiger <- function (path = NULL){

    # get user permission
    message(paste(
        "Set path to the directory storing downloaded and processed TIGER data",
        "by adding a vairable 'PATH_TO_TIGER' to your .Renviron file.",
        "If no path is set, the data will be saved to a temperory directory",
        "that will not be available for future R sessions.\n"
    ))

    cat("Your choice:")

    choice <- switch(
        menu(c("temporary path for this R session",
               "permanent path for this and all future R sessions")),
        "temporary",
        "permanent"
    )

    if (choice == "permanent") {
        if (is.null(path)){
            message(paste("Please specify path to directory storing TIGER data,",
                          "such as E:/tiger_data or ~/my_tiger_data."))
            path <- readline("Input path here >> ")
        }

        # Windows does not recognize directory ending with "/", so delete "/" if path
        # is ended with it.
        path_end <- str_trim(path) %>%
            str_extract(".$")
        if (path_end == "/") {
            path <- str_replace(path, "/$", "")
        }

        if (!dir.exists(path)){
            dir.create(path)
            message(paste0("Directory ", path, " has been created."))
        }

        # save initial working directory for later recovery
        initial_wd <- getwd()

        # set working directory to home directory
        setwd(Sys.getenv("HOME"))

        if (!file.exists(".Renviron")) {
            file.create(".Renviron")
        } else {
            file.copy(".Renviron", ".Renviron_backup")
            message(paste(
                "Your original .Renviron has been backed up and stored as",
                ".Renviron_backup in your R HOME directory."
            ))
            oldenv = read.table(".Renviron", stringsAsFactors = FALSE)[[1]]
            newenv <- oldenv[!grepl("PATH_TO_TIGER", oldenv)]
            write.table(newenv, ".Renviron", quote = FALSE,
                        sep = "\n", col.names = FALSE, row.names = FALSE)
        }
        path_variable <- paste0("PATH_TO_TIGER=", "'", path, "'")
        write(path_variable, ".Renviron", sep = "\n", append = TRUE)
        readRenviron("~/.Renviron")
        message(paste(
            "Your path to TIGER data has been stored in your .Renviron and can",
            "be accessed by Sys.getenv(\"PATH_TO_TIGER\")"
        ))

        # recover to initial working directory
        setwd(initial_wd)

    } else if (choice == "temporary"){
        Sys.setenv(PATH_TO_TIGER = tempdir())
    }
}