// ==========================================
// SHARED: ЧИСТЫЕ СТРАТЕГИИ НУМЕРАЦИИ
// ==========================================

#let cyrillic_letters = (
  "А", "Б", "В", "Г", "Д", "Е", "Ж", "И", "К", "Л", "М", "Н", "П",
  "Р", "С", "Т", "У", "Ф", "Х", "Ц", "Ш", "Щ", "Э", "Ю", "Я",
)

#let cyrillic_letters_lower = (
  "а", "б", "в", "г", "д", "е", "ж", "и", "к", "л", "м", "н", "п",
  "р", "с", "т", "у", "ф", "х", "ц", "ш", "щ", "э", "ю", "я",
)

#let cyrillic_numbering = (..nums) => {
  let n = nums.pos().first()
  if n > 0 and n <= cyrillic_letters.len() {
    cyrillic_letters.at(n - 1)
  } else {
    str(n)
  }
}

#let cyrillic_lower_numbering = (..nums) => {
  let n = nums.pos().last()
  if n > 0 and n <= cyrillic_letters_lower.len() {
    cyrillic_letters_lower.at(n - 1)
  } else {
    str(n)
  }
}

#let num_11 = (..nums) => nums.pos().map(str).join(".") + "."

#let num_1a = (..nums) => {
  let pos = nums.pos()
  let out = ""
  for (i, n) in pos.enumerate() {
    if calc.rem(i, 2) == 0 {
      out += str(n) + "."
    } else {
      out += cyrillic_lower_numbering(n) + "."
    }
  }
  out
}

#let num_1_a = (..nums) => {
  let pos = nums.pos()
  let n = pos.last()
  if calc.rem(pos.len() - 1, 2) == 0 {
    str(n) + "."
  } else {
    cyrillic_lower_numbering(n) + "."
  }
}

#let attachment_numbering(policy, n) = {
  if policy == "arabic" {
    str(n)
  } else if policy == "cyrillic" {
    cyrillic_numbering(n)
  } else if policy == "none" {
    ""
  } else {
    panic("Scientia / attachment-numbering: неизвестная политика " + repr(policy))
  }
}