@rpidanny/pdf2md/lib/util/string-functions.js

A PDF to Markdown Converter

const MIN_DIGIT_CHAR_CODE = 48
const MAX_DIGIT_CHAR_CODE = 57
const WHITESPACE_CHAR_CODE = 32
const TAB_CHAR_CODE = 9
const DOT_CHAR_CODE = 46

exports.removeLeadingWhitespaces = function removeLeadingWhitespaces (string) {
  while (string.charCodeAt(0) === WHITESPACE_CHAR_CODE) {
    string = string.substring(1, string.length)
  }
  return string
}

exports.removeTrailingWhitespaces = function removeTrailingWhitespaces (string) {
  while (string.charCodeAt(string.length - 1) === WHITESPACE_CHAR_CODE) {
    string = string.substring(0, string.length - 1)
  }
  return string
}

exports.isDigit = function isDigit (charCode) {
  return charCode >= MIN_DIGIT_CHAR_CODE && charCode <= MAX_DIGIT_CHAR_CODE
}

exports.isNumber = function isNumber (string) {
  for (var i = 0; i < string.length; i++) {
    const charCode = string.charCodeAt(i)
    if (!exports.isDigit(charCode)) {
      return false
    }
  }
  return true
}

exports.hasOnly = function hasOnly (string, char) {
  const charCode = char.charCodeAt(0)
  for (var i = 0; i < string.length; i++) {
    const aCharCode = string.charCodeAt(i)
    if (aCharCode !== charCode) {
      return false
    }
  }
  return true
}

exports.hasUpperCaseCharacterInMiddleOfWord = function hasUpperCaseCharacterInMiddleOfWord (text) {
  var beginningOfWord = true
  for (var i = 0; i < text.length; i++) {
    const character = text.charAt(i)
    if (character === ' ') {
      beginningOfWord = true
    } else {
      if (!beginningOfWord && isNaN(character * 1) && character === character.toUpperCase() && character.toUpperCase() !== character.toLowerCase()) {
        return true
      }
      beginningOfWord = false
    }
  }
  return false
}

// Remove whitespace/dots + to uppercase
exports.normalizedCharCodeArray = function normalizedCharCodeArray (string) {
  string = string.toUpperCase()
  return exports.charCodeArray(string).filter(charCode => charCode !== WHITESPACE_CHAR_CODE && charCode !== TAB_CHAR_CODE && charCode !== DOT_CHAR_CODE)
}

exports.charCodeArray = function charCodeArray (string) {
  const charCodes = []
  for (var i = 0; i < string.length; i++) {
    charCodes.push(string.charCodeAt(i))
  }
  return charCodes
}

exports.prefixAfterWhitespace = function prefixAfterWhitespace (prefix, string) {
  if (string.charCodeAt(0) === WHITESPACE_CHAR_CODE) {
    string = exports.removeLeadingWhitespaces(string)
    return ' ' + prefix + string
  } else {
    return prefix + string
  }
}

exports.suffixBeforeWhitespace = function suffixBeforeWhitespace (string, suffix) {
  if (string.charCodeAt(string.length - 1) === WHITESPACE_CHAR_CODE) {
    string = exports.removeTrailingWhitespaces(string)
    return string + suffix + ' '
  } else {
    return string + suffix
  }
}

exports.isListItemCharacter = function isListItemCharacter (string) {
  if (string.length > 1) {
    return false
  }
  const char = string.charAt(0)
  return char === '-' || char === '•' || char === '–'
}

exports.isListItem = function isListItem (string) {
  return /^[\s]*[-•–][\s].*$/g.test(string)
}

exports.isNumberedListItem = function isNumberedListItem (string) {
  return /^[\s]*[\d]*[.][\s].*$/g.test(string)
}

exports.wordMatch = function wordMatch (string1, string2) {
  const words1 = new Set(string1.toUpperCase().split(' '))
  const words2 = new Set(string2.toUpperCase().split(' '))
  const intersection = new Set(
    [...words1].filter(x => words2.has(x)))
  return intersection.size / Math.max(words1.size, words2.size)
}