// Label math for the keyboard layout widget, kept Qt-free so it can be unit
// tested under node (test/shell.d/keyboard-layout-test.sh).

// xkbcli list prints YAML, and every layout and variant block pairs a brief with
// the description hyprctl reports as the active keymap:
//
//   - layout: 'us'
//     variant: ''
//     brief: 'en'
//     description: English (US)
//
// The models and option groups it also prints carry no brief of their own, and
// a brief never carries past the block it was printed in, so neither reaches
// the table.
function layoutBriefs(text) {
  var briefs = {}
  var brief = ""

  String(text || "").split("\n").forEach(function (line) {
    if (/^\s*- /.test(line)) brief = ""

    var field = line.match(/^  (brief|description): (.*)$/)
    if (!field) return

    if (field[1] === "brief") {
      brief = field[2].replace(/^'|'$/g, "")
    } else if (brief) {
      briefs[field[2]] = brief
      brief = ""
    }
  })

  return briefs
}

// The brief is a short language code rather than a country one, which keeps the
// label sensible for the layouts named after a language: Esperanto reads EO and
// Arabic reads AR. It is the same code GNOME shows in its own indicator.
//
// Layouts missing from the table fall back to the first word of the description,
// which reads as ENG/POR but at least says something.
//
// Nearly every brief is a bare two-letter code, but a few tack a script onto it
// (Burmese (Zawgyi) is my-zwg) and the custom layout's is a word, so drop the
// script and cap the result at the same three characters the fallback gets.
// The widget sits between fixed neighbours on the bar and has no room to grow.
function shortLabel(description, briefs) {
  if (!description) return ""

  // A description like "constructor" reaches an inherited member rather than a
  // brief, so take the lookup only when it hands back the string it promises.
  var brief = (briefs || {})[description]
  var label = typeof brief === "string" && brief ? brief.split("-")[0] : description.split(/\s+/)[0]
  return label.substring(0, 3).toUpperCase()
}

if (typeof module !== "undefined") {
  module.exports = {
    layoutBriefs: layoutBriefs,
    shortLabel: shortLabel
  }
}