#' View Info of Dataset or Cohort at UCSC Xena Website Using Web browser

#'

#' This will open dataset/cohort link of UCSC Xena

#' in user's default browser.

#' @param x a [XenaHub] object.

#' @param type one of "dataset" and "cohort".

#' @param multiple if `TRUE`, browse multiple links instead of throwing error.

#' @importFrom utils URLencode browseURL

#' @export

#'

#' @examples

#' \donttest{

#' XenaGenerate(subset = XenaHostNames == "tcgaHub") %>%

#'   XenaFilter(filterDatasets = "clinical") %>%

#'   XenaFilter(filterDatasets = "LUAD") -> to_browse

#' }

XenaBrowse <- function(x, type = c("dataset", "cohort"), multiple = FALSE) { # nocov start

  if (!inherits(x, "XenaHub")) {

    stop("Input x must be a XenaHub object.")

  }

  type <- match.arg(type)

  if (type == "dataset") {

    all_datasets <- datasets(x)

    if (length(all_datasets) != 1) {

      if (!multiple) stop("This function limite 1 dataset to browse.\n Set multiple to TRUE if you want to browse multiple links.")

      for (i in all_datasets) {

        xe_tmp <- XenaFilter(x,

          filterDatasets = i,

          ignore.case = FALSE, fixed = TRUE

        )

        y <- utils::URLencode(

          paste0(

            "https://xenabrowser.net/datapages/?",

            "dataset=", datasets(xe_tmp),

            "&host=", hosts(xe_tmp)

          )

        )

        utils::browseURL(y)

      }

    } else {

      y <- utils::URLencode(

        paste0(

          "https://xenabrowser.net/datapages/?",

          "dataset=", datasets(x),

          "&host=", hosts(x)

        )

      )

      utils::browseURL(y)

    }

  } else {

    all_cohorts <- cohorts(x)

    if (length(all_cohorts) != 1) {

      if (!multiple) stop("This function limite 1 cohort to browse. \n Set multiple to TRUE if you want to browse multiple links.")

      for (i in all_cohorts) {

        xe_tmp <- XenaFilter(x,

          filterCohorts = i,

          ignore.case = FALSE, fixed = TRUE

        )

        y <- utils::URLencode(

          paste0(

            "https://xenabrowser.net/datapages/?",

            "cohort=", cohorts(xe_tmp)

          )

        )

        utils::browseURL(y)

      }

    } else {

      y <- utils::URLencode(

        paste0(

          "https://xenabrowser.net/datapages/?",

          "cohort=", cohorts(x)

        )

      )

      utils::browseURL(y)

    }

  }

  invisible(NULL)

} # nocov end

utils::globalVariables(c("XenaDatasets", "XenaHosts", "ProbeMap"))