eruda/src/Elements/Highlight.js

import { evalCss, $, pxToNum, isStr, each, trim } from '../lib/util'

export default class Highlight {
  constructor($container) {
    this._style = evalCss(require('./Highlight.scss'))

    this._isShow = false

    this._appendTpl($container)
    this._bindEvent()
  }
  setEl(el) {
    this._$target = $(el)
    this._target = el
  }
  show() {
    this._isShow = true
    this.render()
    this._$el.show()
  }
  destroy() {
    evalCss.remove(this._style)
  }
  hide() {
    this._isShow = false
    this._$el.hide()
  }
  render() {
    let { left, width, top, height } = this._$target.offset()

    this._$el.css({ left, top: top - window.scrollY, width, height })

    let computedStyle = getComputedStyle(this._target, '')

    let getNumStyle = name => pxToNum(computedStyle.getPropertyValue(name))

    let ml = getNumStyle('margin-left'),
      mr = getNumStyle('margin-right'),
      mt = getNumStyle('margin-top'),
      mb = getNumStyle('margin-bottom')

    this._$margin.css({
      left: -ml,
      top: -mt,
      width: width + ml + mr,
      height: height + mt + mb
    })

    let bl = getNumStyle('border-left-width'),
      br = getNumStyle('border-right-width'),
      bt = getNumStyle('border-top-width'),
      bb = getNumStyle('border-bottom-width')

    let bw = width - bl - br,
      bh = height - bt - bb

    this._$padding.css({
      left: bl,
      top: bt,
      width: bw,
      height: bh
    })

    let pl = getNumStyle('padding-left'),
      pr = getNumStyle('padding-right'),
      pt = getNumStyle('padding-top'),
      pb = getNumStyle('padding-bottom')

    this._$content.css({
      left: bl + pl,
      top: bl + pt,
      width: bw - pl - pr,
      height: bh - pt - pb
    })

    this._$size
      .css({
        top: -mt - (top - mt < 25 ? 0 : 25),
        left: -ml
      })
      .html(`${formatElName(this._target)} | ${width} × ${height}`)
  }
  _bindEvent() {
    window.addEventListener(
      'scroll',
      () => {
        if (!this._isShow) return
        this.render()
      },
      false
    )
  }
  _appendTpl($container) {
    $container.append(require('./Highlight.hbs')())

    let $el = (this._$el = $('.eruda-elements-highlight'))
    this._$margin = $el.find('.eruda-margin')
    this._$padding = $el.find('.eruda-padding')
    this._$content = $el.find('.eruda-content')
    this._$size = $el.find('.eruda-size')
  }
}

function formatElName(el) {
  let { id, className } = el

  let ret = `<span style="color:#ee78e6">${el.tagName.toLowerCase()}</span>`

  if (id !== '') ret += `<span style="color:#ffab66">#${id}</span>`

  let classes = ''
  if (isStr(className)) {
    each(className.split(/\s+/g), val => {
      if (trim(val) === '') return

      classes += `.${val}`
    })
  }

  ret += `<span style="color:#8ed3fb">${classes}</span>`

  return ret
}