// original author: tromboneher

// Number sections according to a number of schemes, omitting previous leading elements.
// For example, where the numbering pattern "A.I.1." would produce:
//
// A. A part of the story
//   A.I. A chapter
//   A.II. Another chapter
//     A.II.1. A section
//       A.II.1.a. A subsection
//       A.II.1.b. Another subsection
//     A.II.2. Another section
// B. Another part of the story
//   B.I. A chapter in the second part
//   B.II. Another chapter in the second part
//
// clean_numbering("A.", "I.", "1.a.") would produce:
//
// A. A part of the story
//   I. A chapter
//   II. Another chapter
//     1. A section
//       1.a. A subsection
//       1.b. Another subsection
//     2. Another section
// B. Another part of the story
//   I. A chapter in the second part
//   II. Another chapter in the second part
//
#let clean_numbering(..schemes) = {
  (..nums) => {
    let (section, ..subsections) = nums.pos()
    let (section_scheme, ..subschemes) = schemes.pos()

    if subsections.len() == 0 {
      numbering(section_scheme, section)
    } else if subschemes.len() == 0 {
      numbering(section_scheme, ..nums.pos())
    }
    else {
      clean_numbering(..subschemes)(..subsections)
    }
  }
}

#set heading(numbering: clean_numbering("A.", "I.", "1.a."))

= Part
== Chapter
== Another chapter
=== Section
==== Subsection
==== Another subsection
= Another part of the story
== A chapter in the second part
== Another chapter in the second part

// author: roehlichA
// Legal formatting of enumeration
#show enum: it => context {
  // Retrieve the last heading so we know what level to step at
  let headings = query(selector(heading).before(here()))
  let last = headings.at(-1)

  // Combine the output items
  let output = ()
  for item in it.children {
    output.push([
      #counter(heading).step(level: last.level + 1)
      #counter(heading).display()
    ])
    output.push([
      #text(item.body)
      #parbreak()
    ])
  }

  // Display in a grid
  grid(
    columns: (auto, 1fr),
    column-gutter: 1em,
    row-gutter: 1em,
    ..output
  )
}

= Some heading
+ Paragraphs here are preceded with a number so they can be referenced directly.
+ _#lorem(100)_
+ _#lorem(100)_

== A subheading
+ Paragraphs are also numbered correctly in subheadings.
+ _#lorem(50)_
+ _#lorem(50)_