#' @title Interpolate a color palette
#'
#' @param palette Character name of a palette in palettes
#' @param reverse Boolean indicating whether the palette should be reversed
#' @param show_palettes Should the ouput be the set of palettes names to pick from? Default to `FALSE`
#' @param ... Additional arguments to pass to colorRampPalette()
#'
#' @return A color palette
#'
#' @export
palette <- function(palette = "cat_5_main", reverse = FALSE, show_palettes = FALSE, ...) {

  #------ Checks

  # Check that palette is a character scalar
  checkmate::assert_character(palette, len = 1)

  # Check that reverse is a logical scalar
  checkmate::assert_logical(reverse, len = 1)

  # Check that show_palettes is a logical scalar
  checkmate::assert_logical(show_palettes, len = 1)

  #------ Get colors

  # Define palettes
  pals <- list(
    cat_2_yellow = color_pattern("cat_2_yellow")
    , cat_2_light = color_pattern("cat_2_light")
    , cat_2_green = color_pattern("cat_2_green")
    , cat_2_blue = color_pattern("cat_2_blue")
    , cat_5_main = color_pattern("cat_5_main")
    , cat_5_ibm = color_pattern("cat_5_ibm")
    , cat_3_aquamarine = color_pattern("cat_3_aquamarine")
    , cat_3_tol_high_contrast = color_pattern("cat_3_tol_high_contrast")
    , cat_8_tol_adapted = color_pattern("cat_8_tol_adapted")
    , cat_3_custom_1 = c("#003F5C", "#58508D", "#FFA600")
    , cat_4_custom_1 = c("#003F5C", "#7a5195", "#ef5675", "#ffa600")
    , cat_5_custom_1 = c("#003F5C", "#58508d", "#bc5090", "#ff6361", "#ffa600")
    , cat_6_custom_1 = c("#003F5C", "#444e86", "#955196", "#dd5182", "#ff6e54", "#ffa600")
    , div_5_orange_blue = color_pattern("div_5_orange_blue")
    , div_5_green_purple = color_pattern("div_5_green_purple")
  )

  # Return if show palettes
  if (show_palettes) {
    return(names(pals))
  }

  # palette is in pals
  if (palette %notin% names(pals)) {
    rlang::abort(c(
      "Palette not defined",
      "*" = glue::glue("Palette `{palette}` is not defined in the `palettes` list."),
      "i" = "Use `palette(show_palettes = TRUE)` to see all available palettes."
    ))
  }

  #------ Get palette

  pal <- pals[[palette]]

  if (reverse) pal <- rev(pal)

  return(pal)
}