@rpidanny/pdf2md/lib/models/TextItemLineGrouper.js

A PDF to Markdown Converter

// @flow

/*::
import TextItem from './TextItem'
*/

const { sortByX } = require('../util/page-item-functions')

// Groups all text items which are on the same y line
module.exports = class TextItemLineGrouper {
  constructor (options) {
    this.mostUsedDistance = options.mostUsedDistance || 12
  }

  // returns a CombineResult
  group (textItems /*: TextItem[] */) /*: TextItem[][] */ {
    const lines = []
    var currentLine = []
    textItems.forEach(item => {
      if (currentLine.length > 0 && Math.abs(currentLine[0].y - item.y) >= this.mostUsedDistance / 2) {
        lines.push(currentLine)
        currentLine = []
      }
      currentLine.push(item)
    })
    lines.push(currentLine)

    lines.forEach(textItems => {
      // we can't trust order of occurence, esp. footnoteLinks like to come last
      sortByX(textItems)
    })
    return lines
  }
}