carbon/lib/customDomToImage.js

/* eslint-disable */
;(function(global) {
  'use strict'

  var util = newUtil()
  var inliner = newInliner()
  var fontFaces = newFontFaces()
  var images = newImages()

  // Default impl options
  var defaultOptions = {
    // Default is to fail on error, no placeholder
    imagePlaceholder: undefined,
    // Default cache bust is false, it will use the cache
    cacheBust: false
  }

  var domtoimage = {
    toSvg: toSvg,
    toPng: toPng,
    toJpeg: toJpeg,
    toBlob: toBlob,
    toPixelData: toPixelData,
    impl: {
      fontFaces: fontFaces,
      images: images,
      util: util,
      inliner: inliner,
      options: {}
    }
  }

  global.domtoimage = domtoimage

  /**
   * @param {Node} node - The DOM Node object to render
   * @param {Object} options - Rendering options
   * @param {Function} options.filter - Should return true if passed node should be included in the output
   *          (excluding node means excluding it's children as well). Not called on the root node.
   * @param {String} options.bgcolor - color for the background, any valid CSS color value.
   * @param {Number} options.width - width to be applied to node before rendering.
   * @param {Number} options.height - height to be applied to node before rendering.
   * @param {Object} options.style - an object whose properties to be copied to node's style before rendering.
   * @param {Number} options.quality - a Number between 0 and 1 indicating image quality (applicable to JPEG only),
              defaults to 1.0.
   * @param {String} options.imagePlaceholder - dataURL to use as a placeholder for failed images, default behaviour is to fail fast on images we can't fetch
   * @param {Boolean} options.cacheBust - set to true to cache bust by appending the time to the request url
   * @return {Promise} - A promise that is fulfilled with a SVG image data URL
   * */
  function toSvg(node, options) {
    options = options || {}
    copyOptions(options)
    return Promise.resolve(node)
      .then(function(node) {
        return cloneNode(node, options.filter, true)
      })
      .then(embedFonts)
      .then(inlineImages)
      .then(applyOptions)
      .then(function(clone) {
        return makeSvgDataUri(
          clone,
          options.width || util.width(node),
          options.height || util.height(node)
        )
      })

    function applyOptions(clone) {
      if (options.bgcolor) clone.style.backgroundColor = options.bgcolor

      if (options.width) clone.style.width = options.width + 'px'
      if (options.height) clone.style.height = options.height + 'px'

      if (options.style)
        Object.keys(options.style).forEach(function(property) {
          clone.style[property] = options.style[property]
        })

      return clone
    }
  }

  /**
   * @param {Node} node - The DOM Node object to render
   * @param {Object} options - Rendering options, @see {@link toSvg}
   * @return {Promise} - A promise that is fulfilled with a Uint8Array containing RGBA pixel data.
   * */
  function toPixelData(node, options) {
    return draw(node, options || {}).then(function(canvas) {
      return canvas.getContext('2d').getImageData(0, 0, util.width(node), util.height(node)).data
    })
  }

  /**
   * @param {Node} node - The DOM Node object to render
   * @param {Object} options - Rendering options, @see {@link toSvg}
   * @return {Promise} - A promise that is fulfilled with a PNG image data URL
   * */
  function toPng(node, options) {
    return draw(node, options || {}).then(function(canvas) {
      return canvas.toDataURL()
    })
  }

  /**
   * @param {Node} node - The DOM Node object to render
   * @param {Object} options - Rendering options, @see {@link toSvg}
   * @return {Promise} - A promise that is fulfilled with a JPEG image data URL
   * */
  function toJpeg(node, options) {
    options = options || {}
    return draw(node, options).then(function(canvas) {
      return canvas.toDataURL('image/jpeg', options.quality || 1.0)
    })
  }

  /**
   * @param {Node} node - The DOM Node object to render
   * @param {Object} options - Rendering options, @see {@link toSvg}
   * @return {Promise} - A promise that is fulfilled with a PNG image blob
   * */
  function toBlob(node, options) {
    return draw(node, options || {}).then(util.canvasToBlob)
  }

  function copyOptions(options) {
    // Copy options to impl options for use in impl
    if (typeof options.imagePlaceholder === 'undefined') {
      domtoimage.impl.options.imagePlaceholder = defaultOptions.imagePlaceholder
    } else {
      domtoimage.impl.options.imagePlaceholder = options.imagePlaceholder
    }

    if (typeof options.cacheBust === 'undefined') {
      domtoimage.impl.options.cacheBust = defaultOptions.cacheBust
    } else {
      domtoimage.impl.options.cacheBust = options.cacheBust
    }
  }

  function draw(domNode, options) {
    return toSvg(domNode, options)
      .then(util.makeImage)
      .then(util.delay(100))
      .then(function(image) {
        var canvas = newCanvas(domNode)
        canvas.getContext('2d').drawImage(image, 0, 0)
        return canvas
      })

    function newCanvas(domNode) {
      var canvas = document.createElement('canvas')
      canvas.width = options.width || util.width(domNode)
      canvas.height = options.height || util.height(domNode)

      if (options.bgcolor) {
        var ctx = canvas.getContext('2d')
        ctx.fillStyle = options.bgcolor
        ctx.fillRect(0, 0, canvas.width, canvas.height)
      }

      return canvas
    }
  }

  function cloneNode(node, filter, root) {
    if (!root && filter && !filter(node)) return Promise.resolve()

    return Promise.resolve(node)
      .then(makeNodeCopy)
      .then(function(clone) {
        return cloneChildren(node, clone, filter)
      })
      .then(function(clone) {
        return processClone(node, clone)
      })

    function makeNodeCopy(node) {
      if (node instanceof HTMLCanvasElement) return util.makeImage(node.toDataURL())
      return node.cloneNode(false)
    }

    function cloneChildren(original, clone, filter) {
      var children = original.childNodes
      if (children.length === 0) return Promise.resolve(clone)

      return cloneChildrenInOrder(clone, util.asArray(children), filter).then(function() {
        return clone
      })

      function cloneChildrenInOrder(parent, children, filter) {
        var done = Promise.resolve()
        children.forEach(function(child) {
          done = done
            .then(function() {
              return cloneNode(child, filter)
            })
            .then(function(childClone) {
              if (childClone) parent.appendChild(childClone)
            })
        })
        return done
      }
    }

    function processClone(original, clone) {
      if (!(clone instanceof Element)) return clone

      return Promise.resolve()
        .then(cloneStyle)
        .then(clonePseudoElements)
        .then(copyUserInput)
        .then(fixSvg)
        .then(function() {
          return clone
        })

      function cloneStyle() {
        copyStyle(window.getComputedStyle(original), clone.style)

        function copyStyle(source, target) {
          if (source.cssText) target.cssText = source.cssText
          else copyProperties(source, target)

          function copyProperties(source, target) {
            util.asArray(source).forEach(function(name) {
              target.setProperty(
                name,
                source.getPropertyValue(name),
                source.getPropertyPriority(name)
              )
            })
          }
        }
      }

      function clonePseudoElements() {
        ;[':before', ':after'].forEach(function(element) {
          clonePseudoElement(element)
        })

        function clonePseudoElement(element) {
          var style = window.getComputedStyle(original, element)
          var content = style.getPropertyValue('content')

          if (content === '' || content === 'none') return

          var className = util.uid()
          clone.className = clone.className + ' ' + className
          var styleElement = document.createElement('style')
          styleElement.appendChild(formatPseudoElementStyle(className, element, style))
          clone.appendChild(styleElement)

          function formatPseudoElementStyle(className, element, style) {
            var selector = '.' + className + ':' + element
            var cssText = style.cssText ? formatCssText(style) : formatCssProperties(style)
            return document.createTextNode(selector + '{' + cssText + '}')

            function formatCssText(style) {
              var content = style.getPropertyValue('content')
              return style.cssText + ' content: ' + content + ';'
            }

            function formatCssProperties(style) {
              return (
                util
                  .asArray(style)
                  .map(formatProperty)
                  .join('; ') + ';'
              )

              function formatProperty(name) {
                return (
                  name +
                  ': ' +
                  style.getPropertyValue(name) +
                  (style.getPropertyPriority(name) ? ' !important' : '')
                )
              }
            }
          }
        }
      }

      function copyUserInput() {
        if (original instanceof HTMLTextAreaElement) clone.innerHTML = original.value
        if (original instanceof HTMLInputElement) clone.setAttribute('value', original.value)
      }

      function fixSvg() {
        if (!(clone instanceof SVGElement)) return
        clone.setAttribute('xmlns', 'http://www.w3.org/2000/svg')

        if (!(clone instanceof SVGRectElement)) return
        ;['width', 'height'].forEach(function(attribute) {
          var value = clone.getAttribute(attribute)
          if (!value) return

          clone.style.setProperty(attribute, value)
        })
      }
    }
  }

  function embedFonts(node) {
    return fontFaces.resolveAll().then(function(cssText) {
      var styleNode = document.createElement('style')
      node.appendChild(styleNode)
      styleNode.appendChild(document.createTextNode(cssText))
      return node
    })
  }

  function inlineImages(node) {
    return images.inlineAll(node).then(function() {
      return node
    })
  }

  function makeSvgDataUri(node, width, height) {
    return Promise.resolve(node)
      .then(function(node) {
        node.setAttribute('xmlns', 'http://www.w3.org/1999/xhtml')
        return new XMLSerializer().serializeToString(node)
      })
      .then(util.escapeXhtml)
      .then(function(xhtml) {
        return '<foreignObject x="0" y="0" width="100%" height="100%">' + xhtml + '</foreignObject>'
      })
      .then(function(foreignObject) {
        return (
          '<svg xmlns="http://www.w3.org/2000/svg" width="' +
          width +
          '" height="' +
          height +
          '">' +
          foreignObject +
          '</svg>'
        )
      })
      .then(function(svg) {
        return 'data:image/svg+xml;charset=utf-8,' + svg
      })
  }

  function newUtil() {
    return {
      escape: escape,
      parseExtension: parseExtension,
      mimeType: mimeType,
      dataAsUrl: dataAsUrl,
      isDataUrl: isDataUrl,
      canvasToBlob: canvasToBlob,
      resolveUrl: resolveUrl,
      getAndEncode: getAndEncode,
      uid: uid(),
      delay: delay,
      asArray: asArray,
      escapeXhtml: escapeXhtml,
      makeImage: makeImage,
      width: width,
      height: height
    }

    function mimes() {
      /*
           * Only WOFF and EOT mime types for fonts are 'real'
           * see http://www.iana.org/assignments/media-types/media-types.xhtml
           */
      var WOFF = 'application/font-woff'
      var JPEG = 'image/jpeg'

      return {
        woff: WOFF,
        woff2: WOFF,
        ttf: 'application/font-truetype',
        eot: 'application/vnd.ms-fontobject',
        png: 'image/png',
        jpg: JPEG,
        jpeg: JPEG,
        gif: 'image/gif',
        tiff: 'image/tiff',
        svg: 'image/svg+xml'
      }
    }

    function parseExtension(url) {
      var match = /\.([^\.\/]*?)$/g.exec(url)
      if (match) return match[1]
      else return ''
    }

    function mimeType(url) {
      var extension = parseExtension(url).toLowerCase()
      return mimes()[extension] || ''
    }

    function isDataUrl(url) {
      return url.search(/^(data:)/) !== -1
    }

    function toBlob(canvas) {
      return new Promise(function(resolve) {
        var binaryString = window.atob(canvas.toDataURL().split(',')[1])
        var length = binaryString.length
        var binaryArray = new Uint8Array(length)

        for (var i = 0; i < length; i++) binaryArray[i] = binaryString.charCodeAt(i)

        resolve(
          new Blob([binaryArray], {
            type: 'image/png'
          })
        )
      })
    }

    function canvasToBlob(canvas) {
      if (canvas.toBlob)
        return new Promise(function(resolve) {
          canvas.toBlob(resolve)
        })

      return toBlob(canvas)
    }

    function resolveUrl(url, baseUrl) {
      var doc = document.implementation.createHTMLDocument()
      var base = doc.createElement('base')
      doc.head.appendChild(base)
      var a = doc.createElement('a')
      doc.body.appendChild(a)
      base.href = baseUrl
      a.href = url
      return a.href
    }

    function uid() {
      var index = 0

      return function() {
        return 'u' + fourRandomChars() + index++

        function fourRandomChars() {
          /* see http://stackoverflow.com/a/6248722/2519373 */
          return ('0000' + ((Math.random() * Math.pow(36, 4)) << 0).toString(36)).slice(-4)
        }
      }
    }

    function makeImage(uri) {
      return new Promise(function(resolve, reject) {
        var image = new Image()
        image.onload = function() {
          resolve(image)
        }
        image.onerror = reject
        image.src = uri
      })
    }

    function getAndEncode(url) {
      var TIMEOUT = 30000
      if (domtoimage.impl.options.cacheBust) {
        // Cache bypass so we dont have CORS issues with cached images
        // Source: https://developer.mozilla.org/en/docs/Web/API/XMLHttpRequest/Using_XMLHttpRequest#Bypassing_the_cache
        url += (/\?/.test(url) ? '&' : '?') + new Date().getTime()
      }

      return new Promise(function(resolve) {
        var request = new XMLHttpRequest()

        request.onreadystatechange = done
        request.ontimeout = timeout
        request.responseType = 'blob'
        request.timeout = TIMEOUT
        request.open('GET', url, true)
        request.send()

        var placeholder
        if (domtoimage.impl.options.imagePlaceholder) {
          var split = domtoimage.impl.options.imagePlaceholder.split(/,/)
          if (split && split[1]) {
            placeholder = split[1]
          }
        }

        function done() {
          if (request.readyState !== 4) return

          if (request.status !== 200) {
            if (placeholder) {
              resolve(placeholder)
            } else {
              fail('cannot fetch resource: ' + url + ', status: ' + request.status)
            }

            return
          }

          var encoder = new FileReader()
          encoder.onloadend = function() {
            var content = encoder.result.split(/,/)[1]
            resolve(content)
          }
          encoder.readAsDataURL(request.response)
        }

        function timeout() {
          if (placeholder) {
            resolve(placeholder)
          } else {
            fail('timeout of ' + TIMEOUT + 'ms occured while fetching resource: ' + url)
          }
        }

        function fail(message) {
          console.error(message)
          resolve('')
        }
      })
    }

    function dataAsUrl(content, type) {
      return 'data:' + type + ';base64,' + content
    }

    function escape(string) {
      return string.replace(/([.*+?^${}()|\[\]\/\\])/g, '\\$1')
    }

    function delay(ms) {
      return function(arg) {
        return new Promise(function(resolve) {
          setTimeout(function() {
            resolve(arg)
          }, ms)
        })
      }
    }

    function asArray(arrayLike) {
      var array = []
      var length = arrayLike.length
      for (var i = 0; i < length; i++) array.push(arrayLike[i])
      return array
    }

    function escapeXhtml(string) {
      return string.replace(/#/g, '%23').replace(/\n/g, '%0A')
    }

    function width(node) {
      var leftBorder = px(node, 'border-left-width')
      var rightBorder = px(node, 'border-right-width')
      return node.scrollWidth + leftBorder + rightBorder
    }

    function height(node) {
      var topBorder = px(node, 'border-top-width')
      var bottomBorder = px(node, 'border-bottom-width')
      return node.scrollHeight + topBorder + bottomBorder
    }

    function px(node, styleProperty) {
      var value = window.getComputedStyle(node).getPropertyValue(styleProperty)
      return parseFloat(value.replace('px', ''))
    }
  }

  function newInliner() {
    var URL_REGEX = /url\(['"]?([^'"]+?)['"]?\)/g

    return {
      inlineAll: inlineAll,
      shouldProcess: shouldProcess,
      impl: {
        readUrls: readUrls,
        inline: inline
      }
    }

    function shouldProcess(string) {
      return string.search(URL_REGEX) !== -1
    }

    function readUrls(string) {
      var result = []
      var match
      while ((match = URL_REGEX.exec(string)) !== null) {
        result.push(match[1])
      }
      return result.filter(function(url) {
        return !util.isDataUrl(url)
      })
    }

    function inline(string, url, baseUrl, get) {
      return Promise.resolve(url)
        .then(function(url) {
          return baseUrl ? util.resolveUrl(url, baseUrl) : url
        })
        .then(get || util.getAndEncode)
        .then(function(data) {
          return util.dataAsUrl(data, util.mimeType(url))
        })
        .then(function(dataUrl) {
          return string.replace(urlAsRegex(url), '$1' + dataUrl + '$3')
        })

      function urlAsRegex(url) {
        return new RegExp('(url\\([\'"]?)(' + util.escape(url) + ')([\'"]?\\))', 'g')
      }
    }

    function inlineAll(string, baseUrl, get) {
      if (nothingToInline()) return Promise.resolve(string)

      return Promise.resolve(string)
        .then(readUrls)
        .then(function(urls) {
          var done = Promise.resolve(string)
          urls.forEach(function(url) {
            done = done.then(function(string) {
              return inline(string, url, baseUrl, get)
            })
          })
          return done
        })

      function nothingToInline() {
        return !shouldProcess(string)
      }
    }
  }

  function newFontFaces() {
    return {
      resolveAll: resolveAll,
      impl: {
        readAll: readAll
      }
    }

    function resolveAll() {
      return readAll(document)
        .then(function(webFonts) {
          return Promise.all(
            webFonts.map(function(webFont) {
              return webFont.resolve()
            })
          )
        })
        .then(function(cssStrings) {
          return cssStrings.join('\n')
        })
    }

    function readAll() {
      return Promise.resolve(util.asArray(document.styleSheets))
        .then(getCssRules)
        .then(selectWebFontRules)
        .then(function(rules) {
          return rules.map(newWebFont)
        })

      function selectWebFontRules(cssRules) {
        return cssRules
          .filter(function(rule) {
            return rule.type === CSSRule.FONT_FACE_RULE
          })
          .filter(function(rule) {
            return inliner.shouldProcess(rule.style.getPropertyValue('src'))
          })
      }

      function getCssRules(styleSheets) {
        var cssRules = []
        styleSheets.forEach(function(sheet) {
          try {
            util.asArray(sheet.cssRules || []).forEach(cssRules.push.bind(cssRules))
          } catch (e) {
            console.log('Error while reading CSS rules from ' + sheet.href, e.toString())
          }
        })
        return cssRules
      }

      function newWebFont(webFontRule) {
        return {
          resolve: function resolve() {
            var baseUrl = (webFontRule.parentStyleSheet || {}).href
            return inliner.inlineAll(webFontRule.cssText, baseUrl)
          },
          src: function() {
            return webFontRule.style.getPropertyValue('src')
          }
        }
      }
    }
  }

  function newImages() {
    return {
      inlineAll: inlineAll,
      impl: {
        newImage: newImage
      }
    }

    function newImage(element) {
      return {
        inline: inline
      }

      function inline(get) {
        if (util.isDataUrl(element.src)) return Promise.resolve()

        return Promise.resolve(element.src)
          .then(get || util.getAndEncode)
          .then(function(data) {
            return util.dataAsUrl(data, util.mimeType(element.src))
          })
          .then(function(dataUrl) {
            return new Promise(function(resolve, reject) {
              element.onload = resolve
              element.onerror = reject
              element.src = dataUrl
            })
          })
      }
    }

    function inlineAll(node) {
      if (!(node instanceof Element)) return Promise.resolve(node)

      return inlineBackground(node).then(function() {
        if (node instanceof HTMLImageElement) return newImage(node).inline()
        else
          return Promise.all(
            util.asArray(node.childNodes).map(function(child) {
              return inlineAll(child)
            })
          )
      })

      function inlineBackground(node) {
        var background = node.style.getPropertyValue('background')

        if (!background) return Promise.resolve(node)

        return inliner
          .inlineAll(background)
          .then(function(inlined) {
            node.style.setProperty(
              'background',
              inlined,
              node.style.getPropertyPriority('background')
            )
          })
          .then(function() {
            return node
          })
      }
    }
  }
})(this)