epam/miew

import { isString } from 'lodash'
import Loader from './Loader'

// we don't need to detect all kinds of URLs, just the evident ones
const urlStartRegexp = /^(https?|ftp):\/\//i

export default class XHRLoader extends Loader {
  constructor(source, options) {
    super(source, options)

    options = this._options
    this._binary = options.binary === true
  }

  load() {
    return new Promise((resolve, reject) => {
      if (this._abort) {
        throw new Error('Loading aborted')
      }

      const url = this._source
      const request = (this._agent = new XMLHttpRequest())

      request.addEventListener('load', () => {
        if (request.status === 200) {
          resolve(request.response)
        } else {
          reject(new Error(`HTTP ${request.status} while fetching ${url}`))
        }
      })
      request.addEventListener('error', () => {
        reject(new Error('HTTP request failed'))
      })
      request.addEventListener('abort', () => {
        reject(new Error('Loading aborted'))
      })
      request.addEventListener('progress', (event) => {
        this.dispatchEvent(event)
      })

      request.open('GET', url)
      if (this._binary) {
        request.responseType = 'arraybuffer'
      } else {
        request.responseType = 'text'
      }
      request.send()
    })
  }

  static canProbablyLoad(source) {
    return isString(source) && urlStartRegexp.test(source)
  }

  static extractName(source) {
    if (source) {
      const last =
        (source.indexOf('?') + 1 ||
          source.lastIndexOf('#') + 1 ||
          source.length + 1) - 1
      return source.slice(source.lastIndexOf('/', last) + 1, last)
    }
    return undefined
  }
}

XHRLoader.types = ['url']