substance/model/CoordinateAdapter.js

Substance is a JavaScript library for web-based content editing. It provides building blocks for realizing custom text editors and web-based publishing system. It is developed to power our online editing platform [Substance](http://substance.io).

import isArrayEqual from '../util/isArrayEqual'
import Coordinate from './Coordinate'

/*
  Adapter for Coordinate oriented implementations.
  E.g. Coordinate transforms can be applied to update selections
  using OT.

  @internal
*/
class CoordinateAdapter extends Coordinate {
  constructor (owner, pathProperty, offsetProperty) {
    super('SKIP')

    this._owner = owner
    this._pathProp = pathProperty
    this._offsetProp = offsetProperty
    Object.freeze(this)
  }

  equals (other) {
    return (other === this ||
      (isArrayEqual(other.path, this.path) && other.offset === this.offset))
  }

  get path () {
    return this._owner[this._pathProp]
  }

  set path (path) {
    this._owner[this._pathProp] = path
  }

  get offset () {
    return this._owner[this._offsetProp]
  }

  set offset (offset) {
    this._owner[this._offsetProp] = offset
  }

  toJSON () {
    return {
      path: this.path,
      offset: this.offset
    }
  }

  toString () {
    return '(' + this.path.join('.') + ', ' + this.offset + ')'
  }
}

export default CoordinateAdapter