@snippetify/book-reader/src/SelectionManager.js

Book reader utilities

const Events = require('./events')
require('rangy/lib/rangy-textrange')
const Selection = require('./models/Selection')
const rangy = require('rangy/lib/rangy-highlighter')
const classApplier = require('rangy/lib/rangy-classapplier')

class SelectionManager {
  constructor () {
    this.events = {}
    this.rangy = rangy
    this.rootElement = document
  }

  static getInstance () {
    return new SelectionManager()
  }

  setRootElement (element) {
    this.rootElement = element
    return this
  }

  setEvents (events) {
    this.events = events
    return this
  }

  initDispatcher () {
    $(this.rootElement).on('click', e => {
      const event = this.create()
      if (event && !this.fromContextMenu(e)) {
        this.events.notify(Events.textSelected, event)
      }
    }).on('mousedown', e => {
      if (!this.fromContextMenu(e)) {
        this.removePrevious()
      }
    })
    return this
  }

  fromContextMenu (e) {
    return $(e.target).parents('[data-type="context-menu"]').length > 0
  }

  create () {
    const selection = this.rangy.getSelection()
    if (!selection.isCollapsed) {
      this.initHighlighter()
      this.highlighter.highlightSelection('selection')

      const endPage = parseInt($(selection.focusNode).parents('[data-no]').attr('data-no'))
      const endRef = parseFloat($(selection.focusNode).parent('p[data-id]').attr('data-pos'))
      const startPage = parseInt($(selection.anchorNode).parents('[data-no]').attr('data-no'))
      const startRef = parseFloat($(selection.anchorNode).parent('p[data-id]').attr('data-pos'))

      return new Selection({
        pages: [startPage, endPage],
        content: selection.toString(),
        references: [startRef, endRef],
        serialized: this.getLast(this.highlighter.serialize())
      })
    }
  }

  getLast (value) {
    const items = value.split('|')
    return `${items[0]}|${items[items.length - 1]}`
  }

  removePrevious () {
    this.initHighlighter()
    this.highlighter.unhighlightSelection()
    return this
  }

  initHighlighter () {
    if (!this.highlighter) {
      this.highlighter = this.rangy.createHighlighter(document, 'TextRange')
      this.highlighter.addClassApplier(classApplier.createClassApplier('selection'))
    }
  }
}

module.exports = SelectionManager
module.exports.default = SelectionManager