aurelia-dragula/src/util.js

An aurelia compatible version of Dragula

import * as classes from './classes'

class _Util {
  nextEl (el) {
    return el.nextElementSibling || manually()
    function manually () {
      let sibling = el
      do {
        sibling = sibling.nextSibling
      } while (sibling && sibling.nodeType !== 1)
      return sibling
    }
  }

  whichMouseButton (e) {
    if (e.touches !== void 0) { return e.touches.length }
    if (e.which !== void 0 && e.which !== 0) { return e.which } // see https://github.com/bevacqua/dragula/issues/261
    if (e.buttons !== void 0) { return e.buttons }
    let button = e.button
    if (button !== void 0) { // see https://github.com/jquery/jquery/blob/99e8ff1baa7ae341e94bb89c3e84570c7c3ad9ea/src/event.js#L573-L575
      return button & 1 ? 1 : button & 2 ? 3 : (button & 4 ? 2 : 0)
    }
  }

  getParent (el) { return el.parentNode === document ? null : el.parentNode }
  getRectWidth (rect) { return rect.width || (rect.right - rect.left) }
  getRectHeight (rect) { return rect.height || (rect.bottom - rect.top) }
  isInput (el) { return el.tagName === 'INPUT' || el.tagName === 'TEXTAREA' || el.tagName === 'SELECT' || Util.isEditable(el) }
  isEditable (el) {
    if (!el) { return false } // no parents were editable
    if (el.contentEditable === 'false') { return false } // stop the lookup
    if (el.contentEditable === 'true') { return true } // found a contentEditable element in the chain
    return this.isEditable(this.getParent(el)) // contentEditable is set to 'inherit'
  }

  getOffset (el) {
    let rect = el.getBoundingClientRect()
    return {
      left: rect.left + this.getScroll('scrollLeft', 'pageXOffset'),
      top: rect.top + this.getScroll('scrollTop', 'pageYOffset')
    }
  }

  getScroll (scrollProp, offsetProp) {
    if (typeof window[offsetProp] !== 'undefined') {
      return window[offsetProp]
    }
    if (document.documentElement.clientHeight) {
      return document.documentElement[scrollProp]
    }
    return document.body[scrollProp]
  }

  getElementBehindPoint (point, x, y) {
    if (point) {
      classes.add(point, 'gu-hide')
    }

    let el = document.elementFromPoint(x, y)

    if (point) {
      classes.rm(point, 'gu-hide')
    }
    return el
  }

  getEventHost (e) {
    // on touchend event, we have to use `e.changedTouches`
    // see http://stackoverflow.com/questions/7192563/touchend-event-properties
    // see https://github.com/bevacqua/dragula/issues/34
    if (e.targetTouches && e.targetTouches.length) {
      return e.targetTouches[0]
    }
    if (e.changedTouches && e.changedTouches.length) {
      return e.changedTouches[0]
    }
    return e
  }

  getCoord (coord, e) {
    let host = this.getEventHost(e)
    return host[coord]
  }

  getImmediateChild (dropTarget, target) {
    let immediate = target
    while (immediate !== dropTarget && this.getParent(immediate) !== dropTarget) {
      immediate = this.getParent(immediate)
    }
    if (immediate === document.documentElement) {
      return null
    }
    return immediate
  }

  getViewModel (element) {
    if (element && element.au && element.au.controller) {
      if (element.au.controller.viewModel.currentViewModel) {
        return element.au.controller.viewModel.currentViewModel
      } else {
        return element.au.controller.viewModel
      }
    }
    return null
  }
}

let Util = new _Util()
export { Util }