A 1Writer action for adding a footnote to a Markdown document.

1writer-add_footnote.js

// Main Steps

let text = editor.getText()

const range = editor.getSelectedRange()
const label = `[^0]`

text = insertFootnote(text, range[1], label)
text = reorderFootnotes(text)

editor.setText(text)
moveCursor(text)

// Function Definitions

function insertFootnote(text, pos, label) {
  const note = `\n\n${label}: \n`
  return text.slice(0, pos) + label + text.slice(pos) + note
}

function reorderFootnotes(text) {
  text = renameLabels(text)
  text = reorderNotes(text)
  text = cleanLabels(text)
  return text
}

function renameLabels(text) {
  const label_re = /[^\n]\[\^\d+\]/g
  const labels = text.match(label_re)
  labels.forEach(function(label, i) {
    let num = i + 1
    let tmp_label = `[^tmp1_${num}]`
    label = label.substring(1)
    text = text.split(label).join(tmp_label)
  })
  return text
}

function reorderNotes(text) {
  const note_re = /\[\^tmp1_\d+\]: .*/g
  const notes = text.match(note_re)
  const ordered_notes = notes.slice(0).sort()

  notes.forEach(function(note, i) {
    let tmp_note = ordered_notes[i].replace('tmp1', 'tmp2')
    text = text.split(note).join(tmp_note)
  })
  return text
}

function cleanLabels(text) {
  const tmp_re = /(\[\^)tmp\d_(\d+\])/g
  return text.replace(tmp_re, '$1$2')
}

function moveCursor(text) {
  const empty_re = /[\n]\[\^\d+\]: [\n]/
  const empty = text.match(empty_re)
  editor.setSelectedRange(empty.index + empty[0].length - 1)
}