// ==UserScript==
// @name         Save page in reader mode
// @namespace    https://github.com/gildas-lormeau/SingleFile/
// @version      1.0
// @description  Save page in reader mode with SingleFile
// @author       Gildas Lormeau
// @match        *://*/*
// @grant        none
// ==/UserScript==

(function () {
    'use strict';

    dispatchEvent(new CustomEvent("single-file-user-script-init"));

    let styleContent;

    addEventListener("single-file-on-before-capture-request", event => {    
        const article = new Readability(document).parse();
        document.body.innerHTML = "";
        const styleElement = document.createElement("style");
        styleElement.textContent = styleContent;
        document.body.appendChild(styleElement);
        document.body.innerHTML += article.content;
        document.body.classList.add("moz-reader-content");
        document.body.style.setProperty("display", "block");
        document.head.innerHTML = "";
        document.title = article.title;
    });

    styleContent = `

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

/* Avoid adding ID selector rules in this style sheet, since they could
 * inadvertently match elements in the article content. */
:root {
   --close-button-hover: #d94141;
}
body {
  --toolbar-bgcolor: #fbfbfb;
  --toolbar-border: #b5b5b5;
  --toolbar-hover: #ebebeb;
  --popup-bgcolor: #fbfbfb;
  --popup-border: #b5b5b5;
  --font-color: #4c4c4c;
  --icon-fill: #808080;
  /* light colours */
}

body.dark {
  --toolbar-bgcolor: #2a2a2d;
  --toolbar-border: #4B4A50;
  --toolbar-hover: #737373;
  --popup-bgcolor: #4b4a50;
  --popup-border: #65646a;
  --font-color: #fff;
  --icon-fill: #fff;
  /* dark colours */
}

body {
  padding: 64px 51px;
}

body.loaded {
  transition: color 0.4s, background-color 0.4s;
}

body.light {
  color: #333333;
  background-color: #ffffff;
}

body.dark {
  color: #eeeeee;
  background-color: #333333;
}

body.dark *::-moz-selection {
  background-color: #FFFFFF;
  color: #0095DD;
}
body.dark a::-moz-selection {
  color: #DD4800;
}

body.sepia {
  color: #5b4636;
  background-color: #f4ecd8;
}

body.sans-serif,
body.sans-serif .remove-button {
  font-family: Helvetica, Arial, sans-serif;
}

body.serif,
body.serif .remove-button  {
  font-family: Georgia, "Times New Roman", serif;
}

.container {
  --font-size: 12;
  max-width: 30em;
  margin: 0 auto;
  font-size: var(--font-size);
}

.container.content-width1 {
  max-width: 20em;
}

.container.content-width2 {
  max-width: 25em;
}

.container.content-width3 {
  max-width: 30em;
}

.container.content-width4  {
  max-width: 35em;
}

.container.content-width5 {
  max-width: 40em;
}

.container.content-width6 {
  max-width: 45em;
}

.container.content-width7 {
  max-width: 50em;
}

.container.content-width8 {
  max-width: 55em;
}

.container.content-width9 {
  max-width: 60em;
}

/* Override some controls and content styles based on color scheme */

body.light > .container > .header > .domain {
  border-bottom-color: #333333 !important;
}

body.sepia > .container > .header > .domain {
  border-bottom-color: #5b4636 !important;
}

body.dark > .container > .header > .domain {
  border-bottom-color: #eeeeee !important;
}

body.sepia > .container > .footer {
  background-color: #dedad4 !important;
}

body.light blockquote {
  border-inline-start: 2px solid #333333 !important;
}

body.sepia blockquote {
  border-inline-start: 2px solid #5b4636 !important;
}

body.dark blockquote {
  border-inline-start: 2px solid #eeeeee !important;
}

/* Add toolbar transition base on loaded class  */

body.loaded .toolbar {
  transition: transform 0.3s ease-out;
}

body:not(.loaded) .toolbar:-moz-locale-dir(ltr) {
  transform: translateX(-100%);
}

body:not(.loaded) .toolbar:-moz-locale-dir(rtl) {
  transform: translateX(100%);
}

.light-button {
  color: #333333;
  background-color: #ffffff;
}

.dark-button {
  color: #eeeeee;
  background-color: #333333;
}

.sepia-button {
  color: #5b4636;
  background-color: #f4ecd8;
}

.sans-serif-button {
  font-family: Helvetica, Arial, sans-serif;
}

.serif-button {
  font-family: Georgia, "Times New Roman", serif;
}

/* Loading/error message */

.reader-message {
  margin-top: 40px;
  display: none;
  text-align: center;
  width: 100%;
  font-size: 0.9em;
}

/* Header */

.header {
  text-align: start;
  display: none;
}

.domain {
  font-size: 0.9em;
  line-height: 1.48em;
  padding-bottom: 4px;
  font-family: Helvetica, Arial, sans-serif;
  text-decoration: none;
  border-bottom: 1px solid;
  color: #0095dd;
}

.header > h1 {
  font-size: 1.6em;
  line-height: 1.25em;
  width: 100%;
  margin: 30px 0;
  padding: 0;
}

.header > .credits {
  font-size: 0.9em;
  line-height: 1.48em;
  margin: 0 0 10px 0;
  padding: 0;
  font-style: italic;
}

.header > .meta-data {
  font-size: 0.65em;
  margin: 0 0 15px 0;
}

/*======= Controls toolbar =======*/

.toolbar {
  font-family: Helvetica, Arial, sans-serif;
  position: fixed;
  height: 100%;
  top: 0;
  left: 0;
  margin: 0;
  padding: 0;
  list-style: none;
  background-color:  var(--toolbar-bgcolor);
  -moz-user-select: none;
  border-right: 1px solid  var(--toolbar-border);
  z-index: 1;
}

.button {
  display: block;
  background-size: 24px 24px;
  background-repeat: no-repeat;
  color: #333;
  background-color: var(--toolbar-bgcolor);
  height: 40px;
  padding: 0;
}

button {
  -moz-context-properties: fill;
  color: var(--font-color);
  fill: var(--icon-fill);
}

.toolbar .button {
  width: 40px;
  background-position: center;
  margin-right: -1px;
  border-top: 0;
  border-left: 0;
  border-right: 1px solid var(--toolbar-border);
  border-bottom: 1px solid var(--toolbar-border);
  background-color:  var(--toolbar-bgcolor);
}

.button[hidden] {
  display: none;
}

.dropdown {
  text-align: center;
  list-style: none;
  margin: 0;
  padding: 0;
}

.dropdown li {
  margin: 0;
  padding: 0;
}

/*======= Popup =======*/

.dropdown-popup {
  min-width: 300px;
  text-align: start;
  position: absolute;
  left: 48px; /* offset to account for toolbar width */
  z-index: 1000;
  background-color: var(--popup-bgcolor);
  visibility: hidden;
  border-radius: 4px;
  border: 1px solid var(--popup-border);
  border-bottom-width: 0;
  box-shadow: 0 1px 3px #c1c1c1;
}

.keep-open .dropdown-popup {
  z-index: initial;
}

.dropdown-popup > hr {
  display: none;
}

.open > .dropdown-popup {
  visibility: visible;
}

.dropdown-arrow {
  position: absolute;
  top: 30px; /* offset arrow from top of popup */
  left: -16px;
  width: 16px;
  height: 24px;
  background-image: url("chrome://global/skin/reader/RM-Type-Controls-Arrow.svg");
  display: block;
  -moz-context-properties:  fill, stroke;
  fill: var(--popup-bgcolor);
  stroke: var(--popup-border);
}


/*======= Font style popup =======*/

.font-type-buttons,
.font-size-buttons,
.color-scheme-buttons,
.content-width-buttons,
.line-height-buttons {
  display: flex;
  flex-direction: row;
}

.font-type-buttons > button:first-child {
  border-top-left-radius: 3px;
}
.font-type-buttons > button:last-child {
  border-top-right-radius: 3px;
}
.color-scheme-buttons > button:first-child {
  border-bottom-left-radius: 3px;
}
.color-scheme-buttons > button:last-child {
  border-bottom-right-radius: 3px;
}

.font-type-buttons > button,
.font-size-buttons > button,
.color-scheme-buttons > button,
.content-width-buttons > button,
.line-height-buttons > button {
  text-align: center;
  border: 0;
}

.font-type-buttons > button,
.font-size-buttons > button,
.content-width-buttons > button,
.line-height-buttons > button {
  width: 50%;
  background-color: transparent;
  border-left: 1px solid var(--popup-border);
  border-bottom: 1px solid var(--popup-border);
}

.color-scheme-buttons > button {
  width: 33.33%;
  font-size: 14px;
}

.color-scheme-buttons > .dark-button {
  margin-top: -1px;
  height: 61px;
}

.font-type-buttons > button:first-child,
.font-size-buttons > button:first-child,
.content-width-buttons > button:first-child,
.line-height-buttons > button:first-child {
  border-left: 0;
}

.font-type-buttons > button {
  display: inline-block;
  font-size: 62px;
  height: 100px;
}

.font-size-buttons > button,
.color-scheme-buttons > button,
.content-width-buttons > button,
.line-height-buttons > button {
  height: 60px;
}

.font-type-buttons > button:active:hover,
.font-type-buttons > button.selected,
.color-scheme-buttons > button:active:hover,
.color-scheme-buttons > button.selected {
  box-shadow: inset 0 -3px 0 0 #fc6420;
}

.font-type-buttons > button:active:hover,
.font-type-buttons > button.selected {
  border-bottom: 1px solid #FC6420;
}

/* Make the serif button content the same size as the sans-serif button content. */
.font-type-buttons > button > .description {
  font-size: 12px;
  margin-top: -5px;
}

/* Font sizes are different per-platform, so we need custom CSS to line them up. */
.font-type-buttons > .sans-serif-button > .name {
  margin-top: 2px;
}

.font-type-buttons > .sans-serif-button > .description {
  margin-top: -4px;
}

.font-type-buttons > .serif-button > .name {
  font-size: 63px;
}

.button:hover,
.font-size-buttons > button:hover,
.font-type-buttons > button:hover,
.content-width-buttons > button:hover,
.line-height-buttons > button:hover {
  background-color: var(--toolbar-hover);
}

.dropdown.open,
.button:active,
.font-size-buttons > button:active,
.font-size-buttons > button.selected,
.content-width-buttons > button:active,
.content-width-buttons > button.selected,
.line-height-buttons > button:active,
.line-height-buttons > button.selected {
  background-color: #dadada;
}

/* Only used on Android */
.font-size-sample {
  display: none;
}

.minus-button,
.plus-button,
.content-width-minus-button,
.content-width-plus-button,
.line-height-minus-button,
.line-height-plus-button {
  background-color: transparent;
  border: 0;
  background-size: 18px 18px;
  background-repeat: no-repeat;
  background-position: center;
}

/*======= Toolbar icons =======*/

.close-button {
  background-image: url("chrome://global/skin/reader/RM-Close-24x24.svg");
  height: 68px;
  background-position: center 8px;
}

.close-button:hover {
  fill: #fff;
  background-color: var(--close-button-hover);
  border-bottom: 1px solid var(--close-button-hover);
  border-right: 1px solid var(--close-button-hover);
}

.close-button:hover:active {
  background-color: #AE2325;
  border-bottom: 1px solid #AE2325;
  border-right: 1px solid #AE2325;
}

.style-button {
  background-image: url("chrome://global/skin/reader/RM-Type-Controls-24x24.svg");
}

.minus-button {
  background-image: url("chrome://global/skin/reader/RM-Minus-24x24.svg");
}

.plus-button {
  background-image: url("chrome://global/skin/reader/RM-Plus-24x24.svg");
}

.content-width-minus-button {
  background-size: 42px 16px;
  background-image: url("chrome://global/skin/reader/RM-Content-Width-Minus-42x16.svg");
}

.content-width-plus-button {
  background-size: 44px 16px;
  background-image: url("chrome://global/skin/reader/RM-Content-Width-Plus-44x16.svg");
}

.line-height-minus-button {
  background-size: 34px 14px;
  background-image: url("chrome://global/skin/reader/RM-Line-Height-Minus-38x14.svg");
}

.line-height-plus-button {
  background-size: 34px 24px;
  background-image: url("chrome://global/skin/reader/RM-Line-Height-Plus-38x24.svg");
}

@media print {
  .toolbar {
    display: none !important;
  }
}

/*======= Article content =======*/

/* Note that any class names from the original article that we want to match on
 * must be added to CLASSES_TO_PRESERVE in ReaderMode.jsm, so that
 * Readability.js doesn't strip them out */

.moz-reader-content {
  display: none;
  font-size: 1em;
  line-height: 1.6em;
}

.moz-reader-content.line-height1 {
  line-height: 1em;
}

.moz-reader-content.line-height2 {
  line-height: 1.2em;
}

.moz-reader-content.line-height3 {
  line-height: 1.4em;
}

.moz-reader-content.line-height4 {
  line-height: 1.6em;
}

.moz-reader-content.line-height5 {
  line-height: 1.8em;
}

.moz-reader-content.line-height6 {
  line-height: 2.0em;
}

.moz-reader-content.line-height7 {
  line-height: 2.2em;
}

.moz-reader-content.line-height8 {
  line-height: 2.4em;
}

.moz-reader-content.line-height9 {
  line-height: 2.6em;
}

@media print {
  .moz-reader-content p,
  .moz-reader-content code,
  .moz-reader-content pre,
  .moz-reader-content blockquote,
  .moz-reader-content ul,
  .moz-reader-content ol,
  .moz-reader-content li,
  .moz-reader-content figure,
  .moz-reader-content .wp-caption {
    margin: 0 0 10px 0 !important;
    padding: 0 !important;
  }
}

.moz-reader-content h1,
.moz-reader-content h2,
.moz-reader-content h3 {
  font-weight: bold;
}

.moz-reader-content h1 {
  font-size: 1.6em;
  line-height: 1.25em;
}

.moz-reader-content h2 {
  font-size: 1.2em;
  line-height: 1.51em;
}

.moz-reader-content h3 {
  font-size: 1em;
  line-height: 1.66em;
}

.moz-reader-content a:link {
  text-decoration: underline;
  font-weight: normal;
}

.moz-reader-content a:link,
.moz-reader-content a:link:hover,
.moz-reader-content a:link:active {
  color: #0095dd;
}

.moz-reader-content a:visited {
  color: #c2e;
}

.moz-reader-content * {
  max-width: 100%;
  height: auto;
}

.moz-reader-content p,
.moz-reader-content p,
.moz-reader-content code,
.moz-reader-content pre,
.moz-reader-content blockquote,
.moz-reader-content ul,
.moz-reader-content ol,
.moz-reader-content li,
.moz-reader-content figure,
.moz-reader-content .wp-caption {
  margin: -10px -10px 20px -10px;
  padding: 10px;
  border-radius: 5px;
}

.moz-reader-content li {
  margin-bottom: 0;
}

.moz-reader-content li > ul,
.moz-reader-content li > ol {
  margin-bottom: -10px;
}

.moz-reader-content p > img:only-child,
.moz-reader-content p > a:only-child > img:only-child,
.moz-reader-content .wp-caption img,
.moz-reader-content figure img {
  display: block;
}

.moz-reader-content img[moz-reader-center] {
  margin-left: auto;
  margin-right: auto;
}

.moz-reader-content .caption,
.moz-reader-content .wp-caption-text
.moz-reader-content figcaption {
  font-size: 0.9em;
  line-height: 1.48em;
  font-style: italic;
}

.moz-reader-content code,
.moz-reader-content pre {
  white-space: pre-wrap;
}

.moz-reader-content blockquote {
  padding: 0;
  padding-inline-start: 16px;
}

.moz-reader-content ul,
.moz-reader-content ol {
  padding: 0;
}

.moz-reader-content ul {
  padding-inline-start: 30px;
  list-style: disc;
}

.moz-reader-content ol {
  padding-inline-start: 30px;
  list-style: decimal;
}

table,
th,
td {
  border: 1px solid currentColor;
  border-collapse: collapse;
  padding: 6px;
  vertical-align: top;
}

table {
  margin: 5px;
}

/* Visually hide (but don't display: none) screen reader elements */
.moz-reader-content .visually-hidden,
.moz-reader-content .visuallyhidden,
.moz-reader-content .sr-only {
  display: inline-block;
  width: 1px;
  height: 1px;
  margin: -1px;
  overflow: hidden;
  padding: 0;
  border-width: 0;
}

/* Hide elements with common "hidden" class names */
.moz-reader-content .hidden,
.moz-reader-content .invisible {
  display: none;
}

/* Enforce wordpress and similar emoji/smileys aren't sized to be full-width,
 * see bug 1399616 for context. */
.moz-reader-content img.wp-smiley,
.moz-reader-content img.emoji {
  display: inline-block;
  border-width: 0;
  /* height: auto is implied from .moz - reader - content *  rule. */
  width: 1em;
  margin: 0 .07em;
  padding: 0;
}

.reader-show-element {
  display: initial;
} `;

    /*eslint-env es6:false*/
    /* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

    /**
 * This is a relatively lightweight DOMParser that is safe to use in a web
 * worker. This is far from a complete DOM implementation; however, it should
 * contain the minimal set of functionality necessary for Readability.js.
 *
 * Aside from not implementing the full DOM API, there are other quirks to be
 * aware of when using the JSDOMParser:
 *
 *   1) Properly formed HTML/XML must be used. This means you should be extra
 *      careful when using this parser on anything received directly from an
 *      XMLHttpRequest. Providing a serialized string from an XMLSerializer,
 *      however, should be safe (since the browser's XMLSerializer should
 *      generate valid HTML/XML). Therefore, if parsing a document from an XHR,
 *      the recommended approach is to do the XHR in the main thread, use
 *      XMLSerializer.serializeToString() on the responseXML, and pass the
 *      resulting string to the worker.
 *
 *   2) Live NodeLists are not supported. DOM methods and properties such as
 *      getElementsByTagName() and childNodes return standard arrays. If you
 *      want these lists to be updated when nodes are removed or added to the
 *      document, you must take care to manually update them yourself.
 */
    (function (global) {

        // XML only defines these and the numeric ones:

        var entityTable = {
            "lt": "<",
            "gt": ">",
            "amp": "&",
            "quot": '"',
            "apos": "'",
        };

        var reverseEntityTable = {
            "<": "&lt;",
            ">": "&gt;",
            "&": "&amp;",
            '"': "&quot;",
            "'": "&apos;",
        };

        function encodeTextContentHTML(s) {
            return s.replace(/[&<>]/g, function (x) {
                return reverseEntityTable[x];
            });
        }

        function encodeHTML(s) {
            return s.replace(/[&<>'"]/g, function (x) {
                return reverseEntityTable[x];
            });
        }

        function decodeHTML(str) {
            return str.replace(/&(quot|amp|apos|lt|gt);/g, function (match, tag) {
                return entityTable[tag];
            }).replace(/&#(?:x([0-9a-z]{1,4})|([0-9]{1,4}));/gi, function (match, hex, numStr) {
                var num = parseInt(hex || numStr, hex ? 16 : 10); // read num
                return String.fromCharCode(num);
            });
        }

        // When a style is set in JS, map it to the corresponding CSS attribute
        var styleMap = {
            "alignmentBaseline": "alignment-baseline",
            "background": "background",
            "backgroundAttachment": "background-attachment",
            "backgroundClip": "background-clip",
            "backgroundColor": "background-color",
            "backgroundImage": "background-image",
            "backgroundOrigin": "background-origin",
            "backgroundPosition": "background-position",
            "backgroundPositionX": "background-position-x",
            "backgroundPositionY": "background-position-y",
            "backgroundRepeat": "background-repeat",
            "backgroundRepeatX": "background-repeat-x",
            "backgroundRepeatY": "background-repeat-y",
            "backgroundSize": "background-size",
            "baselineShift": "baseline-shift",
            "border": "border",
            "borderBottom": "border-bottom",
            "borderBottomColor": "border-bottom-color",
            "borderBottomLeftRadius": "border-bottom-left-radius",
            "borderBottomRightRadius": "border-bottom-right-radius",
            "borderBottomStyle": "border-bottom-style",
            "borderBottomWidth": "border-bottom-width",
            "borderCollapse": "border-collapse",
            "borderColor": "border-color",
            "borderImage": "border-image",
            "borderImageOutset": "border-image-outset",
            "borderImageRepeat": "border-image-repeat",
            "borderImageSlice": "border-image-slice",
            "borderImageSource": "border-image-source",
            "borderImageWidth": "border-image-width",
            "borderLeft": "border-left",
            "borderLeftColor": "border-left-color",
            "borderLeftStyle": "border-left-style",
            "borderLeftWidth": "border-left-width",
            "borderRadius": "border-radius",
            "borderRight": "border-right",
            "borderRightColor": "border-right-color",
            "borderRightStyle": "border-right-style",
            "borderRightWidth": "border-right-width",
            "borderSpacing": "border-spacing",
            "borderStyle": "border-style",
            "borderTop": "border-top",
            "borderTopColor": "border-top-color",
            "borderTopLeftRadius": "border-top-left-radius",
            "borderTopRightRadius": "border-top-right-radius",
            "borderTopStyle": "border-top-style",
            "borderTopWidth": "border-top-width",
            "borderWidth": "border-width",
            "bottom": "bottom",
            "boxShadow": "box-shadow",
            "boxSizing": "box-sizing",
            "captionSide": "caption-side",
            "clear": "clear",
            "clip": "clip",
            "clipPath": "clip-path",
            "clipRule": "clip-rule",
            "color": "color",
            "colorInterpolation": "color-interpolation",
            "colorInterpolationFilters": "color-interpolation-filters",
            "colorProfile": "color-profile",
            "colorRendering": "color-rendering",
            "content": "content",
            "counterIncrement": "counter-increment",
            "counterReset": "counter-reset",
            "cursor": "cursor",
            "direction": "direction",
            "display": "display",
            "dominantBaseline": "dominant-baseline",
            "emptyCells": "empty-cells",
            "enableBackground": "enable-background",
            "fill": "fill",
            "fillOpacity": "fill-opacity",
            "fillRule": "fill-rule",
            "filter": "filter",
            "cssFloat": "float",
            "floodColor": "flood-color",
            "floodOpacity": "flood-opacity",
            "font": "font",
            "fontFamily": "font-family",
            "fontSize": "font-size",
            "fontStretch": "font-stretch",
            "fontStyle": "font-style",
            "fontVariant": "font-variant",
            "fontWeight": "font-weight",
            "glyphOrientationHorizontal": "glyph-orientation-horizontal",
            "glyphOrientationVertical": "glyph-orientation-vertical",
            "height": "height",
            "imageRendering": "image-rendering",
            "kerning": "kerning",
            "left": "left",
            "letterSpacing": "letter-spacing",
            "lightingColor": "lighting-color",
            "lineHeight": "line-height",
            "listStyle": "list-style",
            "listStyleImage": "list-style-image",
            "listStylePosition": "list-style-position",
            "listStyleType": "list-style-type",
            "margin": "margin",
            "marginBottom": "margin-bottom",
            "marginLeft": "margin-left",
            "marginRight": "margin-right",
            "marginTop": "margin-top",
            "marker": "marker",
            "markerEnd": "marker-end",
            "markerMid": "marker-mid",
            "markerStart": "marker-start",
            "mask": "mask",
            "maxHeight": "max-height",
            "maxWidth": "max-width",
            "minHeight": "min-height",
            "minWidth": "min-width",
            "opacity": "opacity",
            "orphans": "orphans",
            "outline": "outline",
            "outlineColor": "outline-color",
            "outlineOffset": "outline-offset",
            "outlineStyle": "outline-style",
            "outlineWidth": "outline-width",
            "overflow": "overflow",
            "overflowX": "overflow-x",
            "overflowY": "overflow-y",
            "padding": "padding",
            "paddingBottom": "padding-bottom",
            "paddingLeft": "padding-left",
            "paddingRight": "padding-right",
            "paddingTop": "padding-top",
            "page": "page",
            "pageBreakAfter": "page-break-after",
            "pageBreakBefore": "page-break-before",
            "pageBreakInside": "page-break-inside",
            "pointerEvents": "pointer-events",
            "position": "position",
            "quotes": "quotes",
            "resize": "resize",
            "right": "right",
            "shapeRendering": "shape-rendering",
            "size": "size",
            "speak": "speak",
            "src": "src",
            "stopColor": "stop-color",
            "stopOpacity": "stop-opacity",
            "stroke": "stroke",
            "strokeDasharray": "stroke-dasharray",
            "strokeDashoffset": "stroke-dashoffset",
            "strokeLinecap": "stroke-linecap",
            "strokeLinejoin": "stroke-linejoin",
            "strokeMiterlimit": "stroke-miterlimit",
            "strokeOpacity": "stroke-opacity",
            "strokeWidth": "stroke-width",
            "tableLayout": "table-layout",
            "textAlign": "text-align",
            "textAnchor": "text-anchor",
            "textDecoration": "text-decoration",
            "textIndent": "text-indent",
            "textLineThrough": "text-line-through",
            "textLineThroughColor": "text-line-through-color",
            "textLineThroughMode": "text-line-through-mode",
            "textLineThroughStyle": "text-line-through-style",
            "textLineThroughWidth": "text-line-through-width",
            "textOverflow": "text-overflow",
            "textOverline": "text-overline",
            "textOverlineColor": "text-overline-color",
            "textOverlineMode": "text-overline-mode",
            "textOverlineStyle": "text-overline-style",
            "textOverlineWidth": "text-overline-width",
            "textRendering": "text-rendering",
            "textShadow": "text-shadow",
            "textTransform": "text-transform",
            "textUnderline": "text-underline",
            "textUnderlineColor": "text-underline-color",
            "textUnderlineMode": "text-underline-mode",
            "textUnderlineStyle": "text-underline-style",
            "textUnderlineWidth": "text-underline-width",
            "top": "top",
            "unicodeBidi": "unicode-bidi",
            "unicodeRange": "unicode-range",
            "vectorEffect": "vector-effect",
            "verticalAlign": "vertical-align",
            "visibility": "visibility",
            "whiteSpace": "white-space",
            "widows": "widows",
            "width": "width",
            "wordBreak": "word-break",
            "wordSpacing": "word-spacing",
            "wordWrap": "word-wrap",
            "writingMode": "writing-mode",
            "zIndex": "z-index",
            "zoom": "zoom",
        };

        // Elements that can be self-closing
        var voidElems = {
            "area": true,
            "base": true,
            "br": true,
            "col": true,
            "command": true,
            "embed": true,
            "hr": true,
            "img": true,
            "input": true,
            "link": true,
            "meta": true,
            "param": true,
            "source": true,
            "wbr": true
        };

        var whitespace = [" ", "\t", "\n", "\r"];

        // See http://www.w3schools.com/dom/dom_nodetype.asp
        var nodeTypes = {
            ELEMENT_NODE: 1,
            ATTRIBUTE_NODE: 2,
            TEXT_NODE: 3,
            CDATA_SECTION_NODE: 4,
            ENTITY_REFERENCE_NODE: 5,
            ENTITY_NODE: 6,
            PROCESSING_INSTRUCTION_NODE: 7,
            COMMENT_NODE: 8,
            DOCUMENT_NODE: 9,
            DOCUMENT_TYPE_NODE: 10,
            DOCUMENT_FRAGMENT_NODE: 11,
            NOTATION_NODE: 12
        };

        function getElementsByTagName(tag) {
            tag = tag.toUpperCase();
            var elems = [];
            var allTags = (tag === "*");
            function getElems(node) {
                var length = node.children.length;
                for (var i = 0; i < length; i++) {
                    var child = node.children[i];
                    if (allTags || (child.tagName === tag))
                        elems.push(child);
                    getElems(child);
                }
            }
            getElems(this);
            return elems;
        }

        var Node = function () { };

        Node.prototype = {
            attributes: null,
            childNodes: null,
            localName: null,
            nodeName: null,
            parentNode: null,
            textContent: null,
            nextSibling: null,
            previousSibling: null,

            get firstChild() {
                return this.childNodes[0] || null;
            },

            get firstElementChild() {
                return this.children[0] || null;
            },

            get lastChild() {
                return this.childNodes[this.childNodes.length - 1] || null;
            },

            get lastElementChild() {
                return this.children[this.children.length - 1] || null;
            },

            appendChild: function (child) {
                if (child.parentNode) {
                    child.parentNode.removeChild(child);
                }

                var last = this.lastChild;
                if (last)
                    last.nextSibling = child;
                child.previousSibling = last;

                if (child.nodeType === Node.ELEMENT_NODE) {
                    child.previousElementSibling = this.children[this.children.length - 1] || null;
                    this.children.push(child);
                    child.previousElementSibling && (child.previousElementSibling.nextElementSibling = child);
                }
                this.childNodes.push(child);
                child.parentNode = this;
            },

            removeChild: function (child) {
                var childNodes = this.childNodes;
                var childIndex = childNodes.indexOf(child);
                if (childIndex === -1) {
                    throw "removeChild: node not found";
                } else {
                    child.parentNode = null;
                    var prev = child.previousSibling;
                    var next = child.nextSibling;
                    if (prev)
                        prev.nextSibling = next;
                    if (next)
                        next.previousSibling = prev;

                    if (child.nodeType === Node.ELEMENT_NODE) {
                        prev = child.previousElementSibling;
                        next = child.nextElementSibling;
                        if (prev)
                            prev.nextElementSibling = next;
                        if (next)
                            next.previousElementSibling = prev;
                        this.children.splice(this.children.indexOf(child), 1);
                    }

                    child.previousSibling = child.nextSibling = null;
                    child.previousElementSibling = child.nextElementSibling = null;

                    return childNodes.splice(childIndex, 1)[0];
                }
            },

            replaceChild: function (newNode, oldNode) {
                var childNodes = this.childNodes;
                var childIndex = childNodes.indexOf(oldNode);
                if (childIndex === -1) {
                    throw "replaceChild: node not found";
                } else {
                    // This will take care of updating the new node if it was somewhere else before:
                    if (newNode.parentNode)
                        newNode.parentNode.removeChild(newNode);

                    childNodes[childIndex] = newNode;

                    // update the new node's sibling properties, and its new siblings' sibling properties
                    newNode.nextSibling = oldNode.nextSibling;
                    newNode.previousSibling = oldNode.previousSibling;
                    if (newNode.nextSibling)
                        newNode.nextSibling.previousSibling = newNode;
                    if (newNode.previousSibling)
                        newNode.previousSibling.nextSibling = newNode;

                    newNode.parentNode = this;

                    // Now deal with elements before we clear out those values for the old node,
                    // because it can help us take shortcuts here:
                    if (newNode.nodeType === Node.ELEMENT_NODE) {
                        if (oldNode.nodeType === Node.ELEMENT_NODE) {
                            // Both were elements, which makes this easier, we just swap things out:
                            newNode.previousElementSibling = oldNode.previousElementSibling;
                            newNode.nextElementSibling = oldNode.nextElementSibling;
                            if (newNode.previousElementSibling)
                                newNode.previousElementSibling.nextElementSibling = newNode;
                            if (newNode.nextElementSibling)
                                newNode.nextElementSibling.previousElementSibling = newNode;
                            this.children[this.children.indexOf(oldNode)] = newNode;
                        } else {
                            // Hard way:
                            newNode.previousElementSibling = (function () {
                                for (var i = childIndex - 1; i >= 0; i--) {
                                    if (childNodes[i].nodeType === Node.ELEMENT_NODE)
                                        return childNodes[i];
                                }
                                return null;
                            })();
                            if (newNode.previousElementSibling) {
                                newNode.nextElementSibling = newNode.previousElementSibling.nextElementSibling;
                            } else {
                                newNode.nextElementSibling = (function () {
                                    for (var i = childIndex + 1; i < childNodes.length; i++) {
                                        if (childNodes[i].nodeType === Node.ELEMENT_NODE)
                                            return childNodes[i];
                                    }
                                    return null;
                                })();
                            }
                            if (newNode.previousElementSibling)
                                newNode.previousElementSibling.nextElementSibling = newNode;
                            if (newNode.nextElementSibling)
                                newNode.nextElementSibling.previousElementSibling = newNode;

                            if (newNode.nextElementSibling)
                                this.children.splice(this.children.indexOf(newNode.nextElementSibling), 0, newNode);
                            else
                                this.children.push(newNode);
                        }
                    } else if (oldNode.nodeType === Node.ELEMENT_NODE) {
                        // new node is not an element node.
                        // if the old one was, update its element siblings:
                        if (oldNode.previousElementSibling)
                            oldNode.previousElementSibling.nextElementSibling = oldNode.nextElementSibling;
                        if (oldNode.nextElementSibling)
                            oldNode.nextElementSibling.previousElementSibling = oldNode.previousElementSibling;
                        this.children.splice(this.children.indexOf(oldNode), 1);

                        // If the old node wasn't an element, neither the new nor the old node was an element,
                        // and the children array and its members shouldn't need any updating.
                    }


                    oldNode.parentNode = null;
                    oldNode.previousSibling = null;
                    oldNode.nextSibling = null;
                    if (oldNode.nodeType === Node.ELEMENT_NODE) {
                        oldNode.previousElementSibling = null;
                        oldNode.nextElementSibling = null;
                    }
                    return oldNode;
                }
            },

            __JSDOMParser__: true,
        };

        for (var nodeType in nodeTypes) {
            Node[nodeType] = Node.prototype[nodeType] = nodeTypes[nodeType];
        }

        var Attribute = function (name, value) {
            this.name = name;
            this._value = value;
        };

        Attribute.prototype = {
            get value() {
                return this._value;
            },
            setValue: function (newValue) {
                this._value = newValue;
            },
            getEncodedValue: function () {
                return encodeHTML(this._value);
            },
        };

        var Comment = function () {
            this.childNodes = [];
        };

        Comment.prototype = {
            __proto__: Node.prototype,

            nodeName: "#comment",
            nodeType: Node.COMMENT_NODE
        };

        var Text = function () {
            this.childNodes = [];
        };

        Text.prototype = {
            __proto__: Node.prototype,

            nodeName: "#text",
            nodeType: Node.TEXT_NODE,
            get textContent() {
                if (typeof this._textContent === "undefined") {
                    this._textContent = decodeHTML(this._innerHTML || "");
                }
                return this._textContent;
            },
            get innerHTML() {
                if (typeof this._innerHTML === "undefined") {
                    this._innerHTML = encodeTextContentHTML(this._textContent || "");
                }
                return this._innerHTML;
            },

            set innerHTML(newHTML) {
                this._innerHTML = newHTML;
                delete this._textContent;
            },
            set textContent(newText) {
                this._textContent = newText;
                delete this._innerHTML;
            },
        };

        var Document = function (url) {
            this.documentURI = url;
            this.styleSheets = [];
            this.childNodes = [];
            this.children = [];
        };

        Document.prototype = {
            __proto__: Node.prototype,

            nodeName: "#document",
            nodeType: Node.DOCUMENT_NODE,
            title: "",

            getElementsByTagName: getElementsByTagName,

            getElementById: function (id) {
                function getElem(node) {
                    var length = node.children.length;
                    if (node.id === id)
                        return node;
                    for (var i = 0; i < length; i++) {
                        var el = getElem(node.children[i]);
                        if (el)
                            return el;
                    }
                    return null;
                }
                return getElem(this);
            },

            createElement: function (tag) {
                var node = new Element(tag);
                return node;
            },

            createTextNode: function (text) {
                var node = new Text();
                node.textContent = text;
                return node;
            },

            get baseURI() {
                if (!this.hasOwnProperty("_baseURI")) {
                    this._baseURI = this.documentURI;
                    var baseElements = this.getElementsByTagName("base");
                    var href = baseElements[0] && baseElements[0].getAttribute("href");
                    if (href) {
                        try {
                            this._baseURI = (new URL(href, this._baseURI)).href;
                        } catch (ex) {/* Just fall back to documentURI */ }
                    }
                }
                return this._baseURI;
            },
        };

        var Element = function (tag) {
            // We use this to find the closing tag.
            this._matchingTag = tag;
            // We're explicitly a non-namespace aware parser, we just pretend it's all HTML.
            var lastColonIndex = tag.lastIndexOf(":");
            if (lastColonIndex != -1) {
                tag = tag.substring(lastColonIndex + 1);
            }
            this.attributes = [];
            this.childNodes = [];
            this.children = [];
            this.nextElementSibling = this.previousElementSibling = null;
            this.localName = tag.toLowerCase();
            this.tagName = tag.toUpperCase();
            this.style = new Style(this);
        };

        Element.prototype = {
            __proto__: Node.prototype,

            nodeType: Node.ELEMENT_NODE,

            getElementsByTagName: getElementsByTagName,

            get className() {
                return this.getAttribute("class") || "";
            },

            set className(str) {
                this.setAttribute("class", str);
            },

            get id() {
                return this.getAttribute("id") || "";
            },

            set id(str) {
                this.setAttribute("id", str);
            },

            get href() {
                return this.getAttribute("href") || "";
            },

            set href(str) {
                this.setAttribute("href", str);
            },

            get src() {
                return this.getAttribute("src") || "";
            },

            set src(str) {
                this.setAttribute("src", str);
            },

            get srcset() {
                return this.getAttribute("srcset") || "";
            },

            set srcset(str) {
                this.setAttribute("srcset", str);
            },

            get nodeName() {
                return this.tagName;
            },

            get innerHTML() {
                function getHTML(node) {
                    var i = 0;
                    for (i = 0; i < node.childNodes.length; i++) {
                        var child = node.childNodes[i];
                        if (child.localName) {
                            arr.push("<" + child.localName);

                            // serialize attribute list
                            for (var j = 0; j < child.attributes.length; j++) {
                                var attr = child.attributes[j];
                                // the attribute value will be HTML escaped.
                                var val = attr.getEncodedValue();
                                var quote = (val.indexOf('"') === -1 ? '"' : "'");
                                arr.push(" " + attr.name + "=" + quote + val + quote);
                            }

                            if (child.localName in voidElems && !child.childNodes.length) {
                                // if this is a self-closing element, end it here
                                arr.push("/>");
                            } else {
                                // otherwise, add its children
                                arr.push(">");
                                getHTML(child);
                                arr.push("</" + child.localName + ">");
                            }
                        } else {
                            // This is a text node, so asking for innerHTML won't recurse.
                            arr.push(child.innerHTML);
                        }
                    }
                }

                // Using Array.join() avoids the overhead from lazy string concatenation.
                // See http://blog.cdleary.com/2012/01/string-representation-in-spidermonkey/#ropes
                var arr = [];
                getHTML(this);
                return arr.join("");
            },

            set innerHTML(html) {
                var parser = new JSDOMParser();
                var node = parser.parse(html);
                var i;
                for (i = this.childNodes.length; --i >= 0;) {
                    this.childNodes[i].parentNode = null;
                }
                this.childNodes = node.childNodes;
                this.children = node.children;
                for (i = this.childNodes.length; --i >= 0;) {
                    this.childNodes[i].parentNode = this;
                }
            },

            set textContent(text) {
                // clear parentNodes for existing children
                for (var i = this.childNodes.length; --i >= 0;) {
                    this.childNodes[i].parentNode = null;
                }

                var node = new Text();
                this.childNodes = [node];
                this.children = [];
                node.textContent = text;
                node.parentNode = this;
            },

            get textContent() {
                function getText(node) {
                    var nodes = node.childNodes;
                    for (var i = 0; i < nodes.length; i++) {
                        var child = nodes[i];
                        if (child.nodeType === 3) {
                            text.push(child.textContent);
                        } else {
                            getText(child);
                        }
                    }
                }

                // Using Array.join() avoids the overhead from lazy string concatenation.
                // See http://blog.cdleary.com/2012/01/string-representation-in-spidermonkey/#ropes
                var text = [];
                getText(this);
                return text.join("");
            },

            getAttribute: function (name) {
                for (var i = this.attributes.length; --i >= 0;) {
                    var attr = this.attributes[i];
                    if (attr.name === name) {
                        return attr.value;
                    }
                }
                return undefined;
            },

            setAttribute: function (name, value) {
                for (var i = this.attributes.length; --i >= 0;) {
                    var attr = this.attributes[i];
                    if (attr.name === name) {
                        attr.setValue(value);
                        return;
                    }
                }
                this.attributes.push(new Attribute(name, value));
            },

            removeAttribute: function (name) {
                for (var i = this.attributes.length; --i >= 0;) {
                    var attr = this.attributes[i];
                    if (attr.name === name) {
                        this.attributes.splice(i, 1);
                        break;
                    }
                }
            },

            hasAttribute: function (name) {
                return this.attributes.some(function (attr) {
                    return attr.name == name;
                });
            },
        };

        var Style = function (node) {
            this.node = node;
        };

        // getStyle() and setStyle() use the style attribute string directly. This
        // won't be very efficient if there are a lot of style manipulations, but
        // it's the easiest way to make sure the style attribute string and the JS
        // style property stay in sync. Readability.js doesn't do many style
        // manipulations, so this should be okay.
        Style.prototype = {
            getStyle: function (styleName) {
                var attr = this.node.getAttribute("style");
                if (!attr)
                    return undefined;

                var styles = attr.split(";");
                for (var i = 0; i < styles.length; i++) {
                    var style = styles[i].split(":");
                    var name = style[0].trim();
                    if (name === styleName)
                        return style[1].trim();
                }

                return undefined;
            },

            setStyle: function (styleName, styleValue) {
                var value = this.node.getAttribute("style") || "";
                var index = 0;
                do {
                    var next = value.indexOf(";", index) + 1;
                    var length = next - index - 1;
                    var style = (length > 0 ? value.substr(index, length) : value.substr(index));
                    if (style.substr(0, style.indexOf(":")).trim() === styleName) {
                        value = value.substr(0, index).trim() + (next ? " " + value.substr(next).trim() : "");
                        break;
                    }
                    index = next;
                } while (index);

                value += " " + styleName + ": " + styleValue + ";";
                this.node.setAttribute("style", value.trim());
            }
        };

        // For each item in styleMap, define a getter and setter on the style
        // property.
        for (var jsName in styleMap) {
            (function (cssName) {
                Style.prototype.__defineGetter__(jsName, function () {
                    return this.getStyle(cssName);
                });
                Style.prototype.__defineSetter__(jsName, function (value) {
                    this.setStyle(cssName, value);
                });
            })(styleMap[jsName]);
        }

        var JSDOMParser = function () {
            this.currentChar = 0;

            // In makeElementNode() we build up many strings one char at a time. Using
            // += for this results in lots of short-lived intermediate strings. It's
            // better to build an array of single-char strings and then join() them
            // together at the end. And reusing a single array (i.e. |this.strBuf|)
            // over and over for this purpose uses less memory than using a new array
            // for each string.
            this.strBuf = [];

            // Similarly, we reuse this array to return the two arguments from
            // makeElementNode(), which saves us from having to allocate a new array
            // every time.
            this.retPair = [];

            this.errorState = "";
        };

        JSDOMParser.prototype = {
            error: function (m) {
                dump("JSDOMParser error: " + m + "\n");
                this.errorState += m + "\n";
            },

            /**
     * Look at the next character without advancing the index.
     */
            peekNext: function () {
                return this.html[this.currentChar];
            },

            /**
     * Get the next character and advance the index.
     */
            nextChar: function () {
                return this.html[this.currentChar++];
            },

            /**
     * Called after a quote character is read. This finds the next quote
     * character and returns the text string in between.
     */
            readString: function (quote) {
                var str;
                var n = this.html.indexOf(quote, this.currentChar);
                if (n === -1) {
                    this.currentChar = this.html.length;
                    str = null;
                } else {
                    str = this.html.substring(this.currentChar, n);
                    this.currentChar = n + 1;
                }

                return str;
            },

            /**
     * Called when parsing a node. This finds the next name/value attribute
     * pair and adds the result to the attributes list.
     */
            readAttribute: function (node) {
                var name = "";

                var n = this.html.indexOf("=", this.currentChar);
                if (n === -1) {
                    this.currentChar = this.html.length;
                } else {
                    // Read until a '=' character is hit; this will be the attribute key
                    name = this.html.substring(this.currentChar, n);
                    this.currentChar = n + 1;
                }

                if (!name)
                    return;

                // After a '=', we should see a '"' for the attribute value
                var c = this.nextChar();
                if (c !== '"' && c !== "'") {
                    this.error("Error reading attribute " + name + ", expecting '\"'");
                    return;
                }

                // Read the attribute value (and consume the matching quote)
                var value = this.readString(c);

                node.attributes.push(new Attribute(name, decodeHTML(value)));

                return;
            },

            /**
     * Parses and returns an Element node. This is called after a '<' has been
     * read.
     *
     * @returns an array; the first index of the array is the parsed node;
     *          the second index is a boolean indicating whether this is a void
     *          Element
     */
            makeElementNode: function (retPair) {
                var c = this.nextChar();

                // Read the Element tag name
                var strBuf = this.strBuf;
                strBuf.length = 0;
                while (whitespace.indexOf(c) == -1 && c !== ">" && c !== "/") {
                    if (c === undefined)
                        return false;
                    strBuf.push(c);
                    c = this.nextChar();
                }
                var tag = strBuf.join("");

                if (!tag)
                    return false;

                var node = new Element(tag);

                // Read Element attributes
                while (c !== "/" && c !== ">") {
                    if (c === undefined)
                        return false;
                    while (whitespace.indexOf(this.html[this.currentChar++]) != -1) {
                        // Advance cursor to first non-whitespace char.
                    }
                    this.currentChar--;
                    c = this.nextChar();
                    if (c !== "/" && c !== ">") {
                        --this.currentChar;
                        this.readAttribute(node);
                    }
                }

                // If this is a self-closing tag, read '/>'
                var closed = false;
                if (c === "/") {
                    closed = true;
                    c = this.nextChar();
                    if (c !== ">") {
                        this.error("expected '>' to close " + tag);
                        return false;
                    }
                }

                retPair[0] = node;
                retPair[1] = closed;
                return true;
            },

            /**
     * If the current input matches this string, advance the input index;
     * otherwise, do nothing.
     *
     * @returns whether input matched string
     */
            match: function (str) {
                var strlen = str.length;
                if (this.html.substr(this.currentChar, strlen).toLowerCase() === str.toLowerCase()) {
                    this.currentChar += strlen;
                    return true;
                }
                return false;
            },

            /**
     * Searches the input until a string is found and discards all input up to
     * and including the matched string.
     */
            discardTo: function (str) {
                var index = this.html.indexOf(str, this.currentChar) + str.length;
                if (index === -1)
                    this.currentChar = this.html.length;
                this.currentChar = index;
            },

            /**
     * Reads child nodes for the given node.
     */
            readChildren: function (node) {
                var child;
                while ((child = this.readNode())) {
                    // Don't keep Comment nodes
                    if (child.nodeType !== 8) {
                        node.appendChild(child);
                    }
                }
            },

            discardNextComment: function () {
                if (this.match("--")) {
                    this.discardTo("-->");
                } else {
                    var c = this.nextChar();
                    while (c !== ">") {
                        if (c === undefined)
                            return null;
                        if (c === '"' || c === "'")
                            this.readString(c);
                        c = this.nextChar();
                    }
                }
                return new Comment();
            },


            /**
     * Reads the next child node from the input. If we're reading a closing
     * tag, or if we've reached the end of input, return null.
     *
     * @returns the node
     */
            readNode: function () {
                var c = this.nextChar();

                if (c === undefined)
                    return null;

                // Read any text as Text node
                var textNode;
                if (c !== "<") {
                    --this.currentChar;
                    textNode = new Text();
                    var n = this.html.indexOf("<", this.currentChar);
                    if (n === -1) {
                        textNode.innerHTML = this.html.substring(this.currentChar, this.html.length);
                        this.currentChar = this.html.length;
                    } else {
                        textNode.innerHTML = this.html.substring(this.currentChar, n);
                        this.currentChar = n;
                    }
                    return textNode;
                }

                if (this.match("![CDATA[")) {
                    var endChar = this.html.indexOf("]]>", this.currentChar);
                    if (endChar === -1) {
                        this.error("unclosed CDATA section");
                        return null;
                    }
                    textNode = new Text();
                    textNode.textContent = this.html.substring(this.currentChar, endChar);
                    this.currentChar = endChar + ("]]>").length;
                    return textNode;
                }

                c = this.peekNext();

                // Read Comment node. Normally, Comment nodes know their inner
                // textContent, but we don't really care about Comment nodes (we throw
                // them away in readChildren()). So just returning an empty Comment node
                // here is sufficient.
                if (c === "!" || c === "?") {
                    // We're still before the ! or ? that is starting this comment:
                    this.currentChar++;
                    return this.discardNextComment();
                }

                // If we're reading a closing tag, return null. This means we've reached
                // the end of this set of child nodes.
                if (c === "/") {
                    --this.currentChar;
                    return null;
                }

                // Otherwise, we're looking at an Element node
                var result = this.makeElementNode(this.retPair);
                if (!result)
                    return null;

                var node = this.retPair[0];
                var closed = this.retPair[1];
                var localName = node.localName;

                // If this isn't a void Element, read its child nodes
                if (!closed) {
                    this.readChildren(node);
                    var closingTag = "</" + node._matchingTag + ">";
                    if (!this.match(closingTag)) {
                        this.error("expected '" + closingTag + "' and got " + this.html.substr(this.currentChar, closingTag.length));
                        return null;
                    }
                }

                // Only use the first title, because SVG might have other
                // title elements which we don't care about (medium.com
                // does this, at least).
                if (localName === "title" && !this.doc.title) {
                    this.doc.title = node.textContent.trim();
                } else if (localName === "head") {
                    this.doc.head = node;
                } else if (localName === "body") {
                    this.doc.body = node;
                } else if (localName === "html") {
                    this.doc.documentElement = node;
                }

                return node;
            },

            /**
     * Parses an HTML string and returns a JS implementation of the Document.
     */
            parse: function (html, url) {
                this.html = html;
                var doc = this.doc = new Document(url);
                this.readChildren(doc);

                // If this is an HTML document, remove root-level children except for the
                // <html> node
                if (doc.documentElement) {
                    for (var i = doc.childNodes.length; --i >= 0;) {
                        var child = doc.childNodes[i];
                        if (child !== doc.documentElement) {
                            doc.removeChild(child);
                        }
                    }
                }

                return doc;
            }
        };

        // Attach the standard DOM types to the global scope
        global.Node = Node;
        global.Comment = Comment;
        global.Document = Document;
        global.Element = Element;
        global.Text = Text;

        // Attach JSDOMParser to the global scope
        global.JSDOMParser = JSDOMParser;

    })(window);


    /*eslint-env es6:false*/
    /*
 * Copyright (c) 2010 Arc90 Inc
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

    /*
 * This code is heavily based on Arc90's readability.js (1.7.1) script
 * available at: http://code.google.com/p/arc90labs-readability
 */

    /**
 * Public constructor.
 * @param {HTMLDocument} doc     The document to parse.
 * @param {Object}       options The options object.
 */
    function Readability(doc, options) {
        // In some older versions, people passed a URI as the first argument. Cope:
        if (options && options.documentElement) {
            doc = options;
            options = arguments[2];
        } else if (!doc || !doc.documentElement) {
            throw new Error("First argument to Readability constructor should be a document object.");
        }
        options = options || {};

        this._doc = doc;
        this._articleTitle = null;
        this._articleByline = null;
        this._articleDir = null;
        this._articleSiteName = null;
        this._attempts = [];

        // Configurable options
        this._debug = !!options.debug;
        this._maxElemsToParse = options.maxElemsToParse || this.DEFAULT_MAX_ELEMS_TO_PARSE;
        this._nbTopCandidates = options.nbTopCandidates || this.DEFAULT_N_TOP_CANDIDATES;
        this._charThreshold = options.charThreshold || this.DEFAULT_CHAR_THRESHOLD;
        this._classesToPreserve = this.CLASSES_TO_PRESERVE.concat(options.classesToPreserve || []);
        this._keepClasses = !!options.keepClasses;

        // Start with all flags set
        this._flags = this.FLAG_STRIP_UNLIKELYS |
            this.FLAG_WEIGHT_CLASSES |
            this.FLAG_CLEAN_CONDITIONALLY;

        var logEl;

        // Control whether log messages are sent to the console
        if (this._debug) {
            logEl = function (e) {
                var rv = e.nodeName + " ";
                if (e.nodeType == e.TEXT_NODE) {
                    return rv + '("' + e.textContent + '")';
                }
                var classDesc = e.className && ("." + e.className.replace(/ /g, "."));
                var elDesc = "";
                if (e.id)
                    elDesc = "(#" + e.id + classDesc + ")";
                else if (classDesc)
                    elDesc = "(" + classDesc + ")";
                return rv + elDesc;
            };
            this.log = function () {
                if (typeof dump !== "undefined") {
                    var msg = Array.prototype.map.call(arguments, function (x) {
                        return (x && x.nodeName) ? logEl(x) : x;
                    }).join(" ");
                    dump("Reader: (Readability) " + msg + "\n");
                } else if (typeof console !== "undefined") {
                    var args = ["Reader: (Readability) "].concat(arguments);
                    console.log.apply(console, args);
                }
            };
        } else {
            this.log = function () { };
        }
    }

    Readability.prototype = {
        FLAG_STRIP_UNLIKELYS: 0x1,
        FLAG_WEIGHT_CLASSES: 0x2,
        FLAG_CLEAN_CONDITIONALLY: 0x4,

        // https://developer.mozilla.org/en-US/docs/Web/API/Node/nodeType
        ELEMENT_NODE: 1,
        TEXT_NODE: 3,

        // Max number of nodes supported by this parser. Default: 0 (no limit)
        DEFAULT_MAX_ELEMS_TO_PARSE: 0,

        // The number of top candidates to consider when analysing how
        // tight the competition is among candidates.
        DEFAULT_N_TOP_CANDIDATES: 5,

        // Element tags to score by default.
        DEFAULT_TAGS_TO_SCORE: "section,h2,h3,h4,h5,h6,p,td,pre".toUpperCase().split(","),

        // The default number of chars an article must have in order to return a result
        DEFAULT_CHAR_THRESHOLD: 500,

        // All of the regular expressions in use within readability.
        // Defined up here so we don't instantiate them repeatedly in loops.
        REGEXPS: {
            // NOTE: These two regular expressions are duplicated in
            // Readability-readerable.js. Please keep both copies in sync.
            unlikelyCandidates: /-ad-|ai2html|banner|breadcrumbs|combx|comment|community|cover-wrap|disqus|extra|footer|gdpr|header|legends|menu|related|remark|replies|rss|shoutbox|sidebar|skyscraper|social|sponsor|supplemental|ad-break|agegate|pagination|pager|popup|yom-remote/i,
            okMaybeItsACandidate: /and|article|body|column|content|main|shadow/i,

            positive: /article|body|content|entry|hentry|h-entry|main|page|pagination|post|text|blog|story/i,
            negative: /hidden|^hid$| hid$| hid |^hid |banner|combx|comment|com-|contact|foot|footer|footnote|gdpr|masthead|media|meta|outbrain|promo|related|scroll|share|shoutbox|sidebar|skyscraper|sponsor|shopping|tags|tool|widget/i,
            extraneous: /print|archive|comment|discuss|e[\-]?mail|share|reply|all|login|sign|single|utility/i,
            byline: /byline|author|dateline|writtenby|p-author/i,
            replaceFonts: /<(\/?)font[^>]*>/gi,
            normalize: /\s{2,}/g,
            videos: /\/\/(www\.)?((dailymotion|youtube|youtube-nocookie|player\.vimeo|v\.qq)\.com|(archive|upload\.wikimedia)\.org|player\.twitch\.tv)/i,
            shareElements: /(\b|_)(share|sharedaddy)(\b|_)/i,
            nextLink: /(next|weiter|continue|>([^\|]|$)|»([^\|]|$))/i,
            prevLink: /(prev|earl|old|new|<|«)/i,
            whitespace: /^\s*$/,
            hasContent: /\S$/,
        },

        DIV_TO_P_ELEMS: ["A", "BLOCKQUOTE", "DL", "DIV", "IMG", "OL", "P", "PRE", "TABLE", "UL", "SELECT"],

        ALTER_TO_DIV_EXCEPTIONS: ["DIV", "ARTICLE", "SECTION", "P"],

        PRESENTATIONAL_ATTRIBUTES: ["align", "background", "bgcolor", "border", "cellpadding", "cellspacing", "frame", "hspace", "rules", "style", "valign", "vspace"],

        DEPRECATED_SIZE_ATTRIBUTE_ELEMS: ["TABLE", "TH", "TD", "HR", "PRE"],

        // The commented out elements qualify as phrasing content but tend to be
        // removed by readability when put into paragraphs, so we ignore them here.
        PHRASING_ELEMS: [
            // "CANVAS", "IFRAME", "SVG", "VIDEO",
            "ABBR", "AUDIO", "B", "BDO", "BR", "BUTTON", "CITE", "CODE", "DATA",
            "DATALIST", "DFN", "EM", "EMBED", "I", "IMG", "INPUT", "KBD", "LABEL",
            "MARK", "MATH", "METER", "NOSCRIPT", "OBJECT", "OUTPUT", "PROGRESS", "Q",
            "RUBY", "SAMP", "SCRIPT", "SELECT", "SMALL", "SPAN", "STRONG", "SUB",
            "SUP", "TEXTAREA", "TIME", "VAR", "WBR"
        ],

        // These are the classes that readability sets itself.
        CLASSES_TO_PRESERVE: ["page"],

        /**
   * Run any post-process modifications to article content as necessary.
   *
   * @param Element
   * @return void
  **/
        _postProcessContent: function (articleContent) {
            // Readability cannot open relative uris so we convert them to absolute uris.
            this._fixRelativeUris(articleContent);

            if (!this._keepClasses) {
                // Remove classes.
                this._cleanClasses(articleContent);
            }
        },

        /**
   * Iterates over a NodeList, calls `filterFn` for each node and removes node
   * if function returned `true`.
   *
   * If function is not passed, removes all the nodes in node list.
   *
   * @param NodeList nodeList The nodes to operate on
   * @param Function filterFn the function to use as a filter
   * @return void
   */
        _removeNodes: function (nodeList, filterFn) {
            for (var i = nodeList.length - 1; i >= 0; i--) {
                var node = nodeList[i];
                var parentNode = node.parentNode;
                if (parentNode) {
                    if (!filterFn || filterFn.call(this, node, i, nodeList)) {
                        parentNode.removeChild(node);
                    }
                }
            }
        },

        /**
   * Iterates over a NodeList, and calls _setNodeTag for each node.
   *
   * @param NodeList nodeList The nodes to operate on
   * @param String newTagName the new tag name to use
   * @return void
   */
        _replaceNodeTags: function (nodeList, newTagName) {
            for (var i = nodeList.length - 1; i >= 0; i--) {
                var node = nodeList[i];
                this._setNodeTag(node, newTagName);
            }
        },

        /**
   * Iterate over a NodeList, which doesn't natively fully implement the Array
   * interface.
   *
   * For convenience, the current object context is applied to the provided
   * iterate function.
   *
   * @param  NodeList nodeList The NodeList.
   * @param  Function fn       The iterate function.
   * @return void
   */
        _forEachNode: function (nodeList, fn) {
            Array.prototype.forEach.call(nodeList, fn, this);
        },

        /**
   * Iterate over a NodeList, return true if any of the provided iterate
   * function calls returns true, false otherwise.
   *
   * For convenience, the current object context is applied to the
   * provided iterate function.
   *
   * @param  NodeList nodeList The NodeList.
   * @param  Function fn       The iterate function.
   * @return Boolean
   */
        _someNode: function (nodeList, fn) {
            return Array.prototype.some.call(nodeList, fn, this);
        },

        /**
   * Iterate over a NodeList, return true if all of the provided iterate
   * function calls return true, false otherwise.
   *
   * For convenience, the current object context is applied to the
   * provided iterate function.
   *
   * @param  NodeList nodeList The NodeList.
   * @param  Function fn       The iterate function.
   * @return Boolean
   */
        _everyNode: function (nodeList, fn) {
            return Array.prototype.every.call(nodeList, fn, this);
        },

        /**
   * Concat all nodelists passed as arguments.
   *
   * @return ...NodeList
   * @return Array
   */
        _concatNodeLists: function () {
            var slice = Array.prototype.slice;
            var args = slice.call(arguments);
            var nodeLists = args.map(function (list) {
                return slice.call(list);
            });
            return Array.prototype.concat.apply([], nodeLists);
        },

        _getAllNodesWithTag: function (node, tagNames) {
            if (node.querySelectorAll) {
                return node.querySelectorAll(tagNames.join(","));
            }
            return [].concat.apply([], tagNames.map(function (tag) {
                var collection = node.getElementsByTagName(tag);
                return Array.isArray(collection) ? collection : Array.from(collection);
            }));
        },

        /**
   * Removes the class="" attribute from every element in the given
   * subtree, except those that match CLASSES_TO_PRESERVE and
   * the classesToPreserve array from the options object.
   *
   * @param Element
   * @return void
   */
        _cleanClasses: function (node) {
            var classesToPreserve = this._classesToPreserve;
            var className = (node.getAttribute("class") || "")
                .split(/\s+/)
                .filter(function (cls) {
                    return classesToPreserve.indexOf(cls) != -1;
                })
                .join(" ");

            if (className) {
                node.setAttribute("class", className);
            } else {
                node.removeAttribute("class");
            }

            for (node = node.firstElementChild; node; node = node.nextElementSibling) {
                this._cleanClasses(node);
            }
        },

        /**
   * Converts each <a> and <img> uri in the given element to an absolute URI,
   * ignoring #ref URIs.
   *
   * @param Element
   * @return void
   */
        _fixRelativeUris: function (articleContent) {
            var baseURI = this._doc.baseURI;
            var documentURI = this._doc.documentURI;
            function toAbsoluteURI(uri) {
                // Leave hash links alone if the base URI matches the document URI:
                if (baseURI == documentURI && uri.charAt(0) == "#") {
                    return uri;
                }
                // Otherwise, resolve against base URI:
                try {
                    return new URL(uri, baseURI).href;
                } catch (ex) {
                    // Something went wrong, just return the original:
                }
                return uri;
            }

            var links = this._getAllNodesWithTag(articleContent, ["a"]);
            this._forEachNode(links, function (link) {
                var href = link.getAttribute("href");
                if (href) {
                    // Replace links with javascript: URIs with text content, since
                    // they won't work after scripts have been removed from the page.
                    if (href.indexOf("javascript:") === 0) {
                        var text = this._doc.createTextNode(link.textContent);
                        link.parentNode.replaceChild(text, link);
                    } else {
                        link.setAttribute("href", toAbsoluteURI(href));
                    }
                }
            });

            var imgs = this._getAllNodesWithTag(articleContent, ["img"]);
            this._forEachNode(imgs, function (img) {
                var src = img.getAttribute("src");
                if (src) {
                    img.setAttribute("src", toAbsoluteURI(src));
                }
            });
        },

        /**
   * Get the article title as an H1.
   *
   * @return void
   **/
        _getArticleTitle: function () {
            var doc = this._doc;
            var curTitle = "";
            var origTitle = "";

            try {
                curTitle = origTitle = doc.title.trim();

                // If they had an element with id "title" in their HTML
                if (typeof curTitle !== "string")
                    curTitle = origTitle = this._getInnerText(doc.getElementsByTagName("title")[0]);
            } catch (e) {/* ignore exceptions setting the title. */ }

            var titleHadHierarchicalSeparators = false;
            function wordCount(str) {
                return str.split(/\s+/).length;
            }

            // If there's a separator in the title, first remove the final part
            if ((/ [\|\-\\\/>»] /).test(curTitle)) {
                titleHadHierarchicalSeparators = / [\\\/>»] /.test(curTitle);
                curTitle = origTitle.replace(/(.*)[\|\-\\\/>»] .*/gi, "$1");

                // If the resulting title is too short (3 words or fewer), remove
                // the first part instead:
                if (wordCount(curTitle) < 3)
                    curTitle = origTitle.replace(/[^\|\-\\\/>»]*[\|\-\\\/>»](.*)/gi, "$1");
            } else if (curTitle.indexOf(": ") !== -1) {
                // Check if we have an heading containing this exact string, so we
                // could assume it's the full title.
                var headings = this._concatNodeLists(
                    doc.getElementsByTagName("h1"),
                    doc.getElementsByTagName("h2")
                );
                var trimmedTitle = curTitle.trim();
                var match = this._someNode(headings, function (heading) {
                    return heading.textContent.trim() === trimmedTitle;
                });

                // If we don't, let's extract the title out of the original title string.
                if (!match) {
                    curTitle = origTitle.substring(origTitle.lastIndexOf(":") + 1);

                    // If the title is now too short, try the first colon instead:
                    if (wordCount(curTitle) < 3) {
                        curTitle = origTitle.substring(origTitle.indexOf(":") + 1);
                        // But if we have too many words before the colon there's something weird
                        // with the titles and the H tags so let's just use the original title instead
                    } else if (wordCount(origTitle.substr(0, origTitle.indexOf(":"))) > 5) {
                        curTitle = origTitle;
                    }
                }
            } else if (curTitle.length > 150 || curTitle.length < 15) {
                var hOnes = doc.getElementsByTagName("h1");

                if (hOnes.length === 1)
                    curTitle = this._getInnerText(hOnes[0]);
            }

            curTitle = curTitle.trim().replace(this.REGEXPS.normalize, " ");
            // If we now have 4 words or fewer as our title, and either no
            // 'hierarchical' separators (\, /, > or ») were found in the original
            // title or we decreased the number of words by more than 1 word, use
            // the original title.
            var curTitleWordCount = wordCount(curTitle);
            if (curTitleWordCount <= 4 &&
                (!titleHadHierarchicalSeparators ||
                    curTitleWordCount != wordCount(origTitle.replace(/[\|\-\\\/>»]+/g, "")) - 1)) {
                curTitle = origTitle;
            }

            return curTitle;
        },

        /**
   * Prepare the HTML document for readability to scrape it.
   * This includes things like stripping javascript, CSS, and handling terrible markup.
   *
   * @return void
   **/
        _prepDocument: function () {
            var doc = this._doc;

            // Remove all style tags in head
            this._removeNodes(doc.getElementsByTagName("style"));

            if (doc.body) {
                this._replaceBrs(doc.body);
            }

            this._replaceNodeTags(doc.getElementsByTagName("font"), "SPAN");
        },

        /**
   * Finds the next element, starting from the given node, and ignoring
   * whitespace in between. If the given node is an element, the same node is
   * returned.
   */
        _nextElement: function (node) {
            var next = node;
            while (next
                && (next.nodeType != this.ELEMENT_NODE)
                && this.REGEXPS.whitespace.test(next.textContent)) {
                next = next.nextSibling;
            }
            return next;
        },

        /**
   * Replaces 2 or more successive <br> elements with a single <p>.
   * Whitespace between <br> elements are ignored. For example:
   *   <div>foo<br>bar<br> <br><br>abc</div>
   * will become:
   *   <div>foo<br>bar<p>abc</p></div>
   */
        _replaceBrs: function (elem) {
            this._forEachNode(this._getAllNodesWithTag(elem, ["br"]), function (br) {
                var next = br.nextSibling;

                // Whether 2 or more <br> elements have been found and replaced with a
                // <p> block.
                var replaced = false;

                // If we find a <br> chain, remove the <br>s until we hit another element
                // or non-whitespace. This leaves behind the first <br> in the chain
                // (which will be replaced with a <p> later).
                while ((next = this._nextElement(next)) && (next.tagName == "BR")) {
                    replaced = true;
                    var brSibling = next.nextSibling;
                    next.parentNode.removeChild(next);
                    next = brSibling;
                }

                // If we removed a <br> chain, replace the remaining <br> with a <p>. Add
                // all sibling nodes as children of the <p> until we hit another <br>
                // chain.
                if (replaced) {
                    var p = this._doc.createElement("p");
                    br.parentNode.replaceChild(p, br);

                    next = p.nextSibling;
                    while (next) {
                        // If we've hit another <br><br>, we're done adding children to this <p>.
                        if (next.tagName == "BR") {
                            var nextElem = this._nextElement(next.nextSibling);
                            if (nextElem && nextElem.tagName == "BR")
                                break;
                        }

                        if (!this._isPhrasingContent(next))
                            break;

                        // Otherwise, make this node a child of the new <p>.
                        var sibling = next.nextSibling;
                        p.appendChild(next);
                        next = sibling;
                    }

                    while (p.lastChild && this._isWhitespace(p.lastChild)) {
                        p.removeChild(p.lastChild);
                    }

                    if (p.parentNode.tagName === "P")
                        this._setNodeTag(p.parentNode, "DIV");
                }
            });
        },

        _setNodeTag: function (node, tag) {
            this.log("_setNodeTag", node, tag);
            if (node.__JSDOMParser__) {
                node.localName = tag.toLowerCase();
                node.tagName = tag.toUpperCase();
                return node;
            }

            var replacement = node.ownerDocument.createElement(tag);
            while (node.firstChild) {
                replacement.appendChild(node.firstChild);
            }
            node.parentNode.replaceChild(replacement, node);
            if (node.readability)
                replacement.readability = node.readability;

            for (var i = 0; i < node.attributes.length; i++) {
                try {
                    replacement.setAttribute(node.attributes[i].name, node.attributes[i].value);
                } catch (ex) {
                    /* it's possible for setAttribute() to throw if the attribute name
         * isn't a valid XML Name. Such attributes can however be parsed from
         * source in HTML docs, see https://github.com/whatwg/html/issues/4275,
         * so we can hit them here and then throw. We don't care about such
         * attributes so we ignore them.
         */
                }
            }
            return replacement;
        },

        /**
   * Prepare the article node for display. Clean out any inline styles,
   * iframes, forms, strip extraneous <p> tags, etc.
   *
   * @param Element
   * @return void
   **/
        _prepArticle: function (articleContent) {
            this._cleanStyles(articleContent);

            // Check for data tables before we continue, to avoid removing items in
            // those tables, which will often be isolated even though they're
            // visually linked to other content-ful elements (text, images, etc.).
            this._markDataTables(articleContent);

            this._fixLazyImages(articleContent);

            // Clean out junk from the article content
            this._cleanConditionally(articleContent, "form");
            this._cleanConditionally(articleContent, "fieldset");
            this._clean(articleContent, "object");
            this._clean(articleContent, "embed");
            this._clean(articleContent, "h1");
            this._clean(articleContent, "footer");
            this._clean(articleContent, "link");
            this._clean(articleContent, "aside");

            // Clean out elements with little content that have "share" in their id/class combinations from final top candidates,
            // which means we don't remove the top candidates even they have "share".

            var shareElementThreshold = this.DEFAULT_CHAR_THRESHOLD;

            this._forEachNode(articleContent.children, function (topCandidate) {
                this._cleanMatchedNodes(topCandidate, function (node, matchString) {
                    return this.REGEXPS.shareElements.test(matchString) && node.textContent.length < shareElementThreshold;
                });
            });

            // If there is only one h2 and its text content substantially equals article title,
            // they are probably using it as a header and not a subheader,
            // so remove it since we already extract the title separately.
            var h2 = articleContent.getElementsByTagName("h2");
            if (h2.length === 1) {
                var lengthSimilarRate = (h2[0].textContent.length - this._articleTitle.length) / this._articleTitle.length;
                if (Math.abs(lengthSimilarRate) < 0.5) {
                    var titlesMatch = false;
                    if (lengthSimilarRate > 0) {
                        titlesMatch = h2[0].textContent.includes(this._articleTitle);
                    } else {
                        titlesMatch = this._articleTitle.includes(h2[0].textContent);
                    }
                    if (titlesMatch) {
                        this._clean(articleContent, "h2");
                    }
                }
            }

            this._clean(articleContent, "iframe");
            this._clean(articleContent, "input");
            this._clean(articleContent, "textarea");
            this._clean(articleContent, "select");
            this._clean(articleContent, "button");
            this._cleanHeaders(articleContent);

            // Do these last as the previous stuff may have removed junk
            // that will affect these
            this._cleanConditionally(articleContent, "table");
            this._cleanConditionally(articleContent, "ul");
            this._cleanConditionally(articleContent, "div");

            // Remove extra paragraphs
            this._removeNodes(articleContent.getElementsByTagName("p"), function (paragraph) {
                var imgCount = paragraph.getElementsByTagName("img").length;
                var embedCount = paragraph.getElementsByTagName("embed").length;
                var objectCount = paragraph.getElementsByTagName("object").length;
                // At this point, nasty iframes have been removed, only remain embedded video ones.
                var iframeCount = paragraph.getElementsByTagName("iframe").length;
                var totalCount = imgCount + embedCount + objectCount + iframeCount;

                return totalCount === 0 && !this._getInnerText(paragraph, false);
            });

            this._forEachNode(this._getAllNodesWithTag(articleContent, ["br"]), function (br) {
                var next = this._nextElement(br.nextSibling);
                if (next && next.tagName == "P")
                    br.parentNode.removeChild(br);
            });

            // Remove single-cell tables
            this._forEachNode(this._getAllNodesWithTag(articleContent, ["table"]), function (table) {
                var tbody = this._hasSingleTagInsideElement(table, "TBODY") ? table.firstElementChild : table;
                if (this._hasSingleTagInsideElement(tbody, "TR")) {
                    var row = tbody.firstElementChild;
                    if (this._hasSingleTagInsideElement(row, "TD")) {
                        var cell = row.firstElementChild;
                        cell = this._setNodeTag(cell, this._everyNode(cell.childNodes, this._isPhrasingContent) ? "P" : "DIV");
                        table.parentNode.replaceChild(cell, table);
                    }
                }
            });
        },

        /**
   * Initialize a node with the readability object. Also checks the
   * className/id for special names to add to its score.
   *
   * @param Element
   * @return void
  **/
        _initializeNode: function (node) {
            node.readability = { "contentScore": 0 };

            switch (node.tagName) {
                case "DIV":
                    node.readability.contentScore += 5;
                    break;

                case "PRE":
                case "TD":
                case "BLOCKQUOTE":
                    node.readability.contentScore += 3;
                    break;

                case "ADDRESS":
                case "OL":
                case "UL":
                case "DL":
                case "DD":
                case "DT":
                case "LI":
                case "FORM":
                    node.readability.contentScore -= 3;
                    break;

                case "H1":
                case "H2":
                case "H3":
                case "H4":
                case "H5":
                case "H6":
                case "TH":
                    node.readability.contentScore -= 5;
                    break;
            }

            node.readability.contentScore += this._getClassWeight(node);
        },

        _removeAndGetNext: function (node) {
            var nextNode = this._getNextNode(node, true);
            node.parentNode.removeChild(node);
            return nextNode;
        },

        /**
   * Traverse the DOM from node to node, starting at the node passed in.
   * Pass true for the second parameter to indicate this node itself
   * (and its kids) are going away, and we want the next node over.
   *
   * Calling this in a loop will traverse the DOM depth-first.
   */
        _getNextNode: function (node, ignoreSelfAndKids) {
            // First check for kids if those aren't being ignored
            if (!ignoreSelfAndKids && node.firstElementChild) {
                return node.firstElementChild;
            }
            // Then for siblings...
            if (node.nextElementSibling) {
                return node.nextElementSibling;
            }
            // And finally, move up the parent chain *and* find a sibling
            // (because this is depth-first traversal, we will have already
            // seen the parent nodes themselves).
            do {
                node = node.parentNode;
            } while (node && !node.nextElementSibling);
            return node && node.nextElementSibling;
        },

        _checkByline: function (node, matchString) {
            if (this._articleByline) {
                return false;
            }

            if (node.getAttribute !== undefined) {
                var rel = node.getAttribute("rel");
                var itemprop = node.getAttribute("itemprop");
            }

            if ((rel === "author" || (itemprop && itemprop.indexOf("author") !== -1) || this.REGEXPS.byline.test(matchString)) && this._isValidByline(node.textContent)) {
                this._articleByline = node.textContent.trim();
                return true;
            }

            return false;
        },

        _getNodeAncestors: function (node, maxDepth) {
            maxDepth = maxDepth || 0;
            var i = 0, ancestors = [];
            while (node.parentNode) {
                ancestors.push(node.parentNode);
                if (maxDepth && ++i === maxDepth)
                    break;
                node = node.parentNode;
            }
            return ancestors;
        },

        /***
   * grabArticle - Using a variety of metrics (content score, classname, element types), find the content that is
   *         most likely to be the stuff a user wants to read. Then return it wrapped up in a div.
   *
   * @param page a document to run upon. Needs to be a full document, complete with body.
   * @return Element
  **/
        _grabArticle: function (page) {
            this.log("**** grabArticle ****");
            var doc = this._doc;
            var isPaging = (page !== null ? true : false);
            page = page ? page : this._doc.body;

            // We can't grab an article if we don't have a page!
            if (!page) {
                this.log("No body found in document. Abort.");
                return null;
            }

            var pageCacheHtml = page.innerHTML;

            while (true) {
                var stripUnlikelyCandidates = this._flagIsActive(this.FLAG_STRIP_UNLIKELYS);

                // First, node prepping. Trash nodes that look cruddy (like ones with the
                // class name "comment", etc), and turn divs into P tags where they have been
                // used inappropriately (as in, where they contain no other block level elements.)
                var elementsToScore = [];
                var node = this._doc.documentElement;

                while (node) {
                    var matchString = node.className + " " + node.id;

                    if (!this._isProbablyVisible(node)) {
                        this.log("Removing hidden node - " + matchString);
                        node = this._removeAndGetNext(node);
                        continue;
                    }

                    // Check to see if this node is a byline, and remove it if it is.
                    if (this._checkByline(node, matchString)) {
                        node = this._removeAndGetNext(node);
                        continue;
                    }

                    // Remove unlikely candidates
                    if (stripUnlikelyCandidates) {
                        if (this.REGEXPS.unlikelyCandidates.test(matchString) &&
                            !this.REGEXPS.okMaybeItsACandidate.test(matchString) &&
                            !this._hasAncestorTag(node, "table") &&
                            node.tagName !== "BODY" &&
                            node.tagName !== "A") {
                            this.log("Removing unlikely candidate - " + matchString);
                            node = this._removeAndGetNext(node);
                            continue;
                        }
                    }

                    // Remove DIV, SECTION, and HEADER nodes without any content(e.g. text, image, video, or iframe).
                    if ((node.tagName === "DIV" || node.tagName === "SECTION" || node.tagName === "HEADER" ||
                        node.tagName === "H1" || node.tagName === "H2" || node.tagName === "H3" ||
                        node.tagName === "H4" || node.tagName === "H5" || node.tagName === "H6") &&
                        this._isElementWithoutContent(node)) {
                        node = this._removeAndGetNext(node);
                        continue;
                    }

                    if (this.DEFAULT_TAGS_TO_SCORE.indexOf(node.tagName) !== -1) {
                        elementsToScore.push(node);
                    }

                    // Turn all divs that don't have children block level elements into p's
                    if (node.tagName === "DIV") {
                        // Put phrasing content into paragraphs.
                        var p = null;
                        var childNode = node.firstChild;
                        while (childNode) {
                            var nextSibling = childNode.nextSibling;
                            if (this._isPhrasingContent(childNode)) {
                                if (p !== null) {
                                    p.appendChild(childNode);
                                } else if (!this._isWhitespace(childNode)) {
                                    p = doc.createElement("p");
                                    node.replaceChild(p, childNode);
                                    p.appendChild(childNode);
                                }
                            } else if (p !== null) {
                                while (p.lastChild && this._isWhitespace(p.lastChild)) {
                                    p.removeChild(p.lastChild);
                                }
                                p = null;
                            }
                            childNode = nextSibling;
                        }

                        // Sites like http://mobile.slate.com encloses each paragraph with a DIV
                        // element. DIVs with only a P element inside and no text content can be
                        // safely converted into plain P elements to avoid confusing the scoring
                        // algorithm with DIVs with are, in practice, paragraphs.
                        if (this._hasSingleTagInsideElement(node, "P") && this._getLinkDensity(node) < 0.25) {
                            var newNode = node.children[0];
                            node.parentNode.replaceChild(newNode, node);
                            node = newNode;
                            elementsToScore.push(node);
                        } else if (!this._hasChildBlockElement(node)) {
                            node = this._setNodeTag(node, "P");
                            elementsToScore.push(node);
                        }
                    }
                    node = this._getNextNode(node);
                }

                /**
       * Loop through all paragraphs, and assign a score to them based on how content-y they look.
       * Then add their score to their parent node.
       *
       * A score is determined by things like number of commas, class names, etc. Maybe eventually link density.
      **/
                var candidates = [];
                this._forEachNode(elementsToScore, function (elementToScore) {
                    if (!elementToScore.parentNode || typeof (elementToScore.parentNode.tagName) === "undefined")
                        return;

                    // If this paragraph is less than 25 characters, don't even count it.
                    var innerText = this._getInnerText(elementToScore);
                    if (innerText.length < 25)
                        return;

                    // Exclude nodes with no ancestor.
                    var ancestors = this._getNodeAncestors(elementToScore, 3);
                    if (ancestors.length === 0)
                        return;

                    var contentScore = 0;

                    // Add a point for the paragraph itself as a base.
                    contentScore += 1;

                    // Add points for any commas within this paragraph.
                    contentScore += innerText.split(",").length;

                    // For every 100 characters in this paragraph, add another point. Up to 3 points.
                    contentScore += Math.min(Math.floor(innerText.length / 100), 3);

                    // Initialize and score ancestors.
                    this._forEachNode(ancestors, function (ancestor, level) {
                        if (!ancestor.tagName || !ancestor.parentNode || typeof (ancestor.parentNode.tagName) === "undefined")
                            return;

                        if (typeof (ancestor.readability) === "undefined") {
                            this._initializeNode(ancestor);
                            candidates.push(ancestor);
                        }

                        // Node score divider:
                        // - parent:             1 (no division)
                        // - grandparent:        2
                        // - great grandparent+: ancestor level * 3
                        if (level === 0)
                            var scoreDivider = 1;
                        else if (level === 1)
                            scoreDivider = 2;
                        else
                            scoreDivider = level * 3;
                        ancestor.readability.contentScore += contentScore / scoreDivider;
                    });
                });

                // After we've calculated scores, loop through all of the possible
                // candidate nodes we found and find the one with the highest score.
                var topCandidates = [];
                for (var c = 0, cl = candidates.length; c < cl; c += 1) {
                    var candidate = candidates[c];

                    // Scale the final candidates score based on link density. Good content
                    // should have a relatively small link density (5% or less) and be mostly
                    // unaffected by this operation.
                    var candidateScore = candidate.readability.contentScore * (1 - this._getLinkDensity(candidate));
                    candidate.readability.contentScore = candidateScore;

                    this.log("Candidate:", candidate, "with score " + candidateScore);

                    for (var t = 0; t < this._nbTopCandidates; t++) {
                        var aTopCandidate = topCandidates[t];

                        if (!aTopCandidate || candidateScore > aTopCandidate.readability.contentScore) {
                            topCandidates.splice(t, 0, candidate);
                            if (topCandidates.length > this._nbTopCandidates)
                                topCandidates.pop();
                            break;
                        }
                    }
                }

                var topCandidate = topCandidates[0] || null;
                var neededToCreateTopCandidate = false;
                var parentOfTopCandidate;

                // If we still have no top candidate, just use the body as a last resort.
                // We also have to copy the body node so it is something we can modify.
                if (topCandidate === null || topCandidate.tagName === "BODY") {
                    // Move all of the page's children into topCandidate
                    topCandidate = doc.createElement("DIV");
                    neededToCreateTopCandidate = true;
                    // Move everything (not just elements, also text nodes etc.) into the container
                    // so we even include text directly in the body:
                    var kids = page.childNodes;
                    while (kids.length) {
                        this.log("Moving child out:", kids[0]);
                        topCandidate.appendChild(kids[0]);
                    }

                    page.appendChild(topCandidate);

                    this._initializeNode(topCandidate);
                } else if (topCandidate) {
                    // Find a better top candidate node if it contains (at least three) nodes which belong to `topCandidates` array
                    // and whose scores are quite closed with current `topCandidate` node.
                    var alternativeCandidateAncestors = [];
                    for (var i = 1; i < topCandidates.length; i++) {
                        if (topCandidates[i].readability.contentScore / topCandidate.readability.contentScore >= 0.75) {
                            alternativeCandidateAncestors.push(this._getNodeAncestors(topCandidates[i]));
                        }
                    }
                    var MINIMUM_TOPCANDIDATES = 3;
                    if (alternativeCandidateAncestors.length >= MINIMUM_TOPCANDIDATES) {
                        parentOfTopCandidate = topCandidate.parentNode;
                        while (parentOfTopCandidate.tagName !== "BODY") {
                            var listsContainingThisAncestor = 0;
                            for (var ancestorIndex = 0; ancestorIndex < alternativeCandidateAncestors.length && listsContainingThisAncestor < MINIMUM_TOPCANDIDATES; ancestorIndex++) {
                                listsContainingThisAncestor += Number(alternativeCandidateAncestors[ancestorIndex].includes(parentOfTopCandidate));
                            }
                            if (listsContainingThisAncestor >= MINIMUM_TOPCANDIDATES) {
                                topCandidate = parentOfTopCandidate;
                                break;
                            }
                            parentOfTopCandidate = parentOfTopCandidate.parentNode;
                        }
                    }
                    if (!topCandidate.readability) {
                        this._initializeNode(topCandidate);
                    }

                    // Because of our bonus system, parents of candidates might have scores
                    // themselves. They get half of the node. There won't be nodes with higher
                    // scores than our topCandidate, but if we see the score going *up* in the first
                    // few steps up the tree, that's a decent sign that there might be more content
                    // lurking in other places that we want to unify in. The sibling stuff
                    // below does some of that - but only if we've looked high enough up the DOM
                    // tree.
                    parentOfTopCandidate = topCandidate.parentNode;
                    var lastScore = topCandidate.readability.contentScore;
                    // The scores shouldn't get too low.
                    var scoreThreshold = lastScore / 3;
                    while (parentOfTopCandidate.tagName !== "BODY") {
                        if (!parentOfTopCandidate.readability) {
                            parentOfTopCandidate = parentOfTopCandidate.parentNode;
                            continue;
                        }
                        var parentScore = parentOfTopCandidate.readability.contentScore;
                        if (parentScore < scoreThreshold)
                            break;
                        if (parentScore > lastScore) {
                            // Alright! We found a better parent to use.
                            topCandidate = parentOfTopCandidate;
                            break;
                        }
                        lastScore = parentOfTopCandidate.readability.contentScore;
                        parentOfTopCandidate = parentOfTopCandidate.parentNode;
                    }

                    // If the top candidate is the only child, use parent instead. This will help sibling
                    // joining logic when adjacent content is actually located in parent's sibling node.
                    parentOfTopCandidate = topCandidate.parentNode;
                    while (parentOfTopCandidate.tagName != "BODY" && parentOfTopCandidate.children.length == 1) {
                        topCandidate = parentOfTopCandidate;
                        parentOfTopCandidate = topCandidate.parentNode;
                    }
                    if (!topCandidate.readability) {
                        this._initializeNode(topCandidate);
                    }
                }

                // Now that we have the top candidate, look through its siblings for content
                // that might also be related. Things like preambles, content split by ads
                // that we removed, etc.
                var articleContent = doc.createElement("DIV");
                if (isPaging)
                    articleContent.id = "readability-content";

                var siblingScoreThreshold = Math.max(10, topCandidate.readability.contentScore * 0.2);
                // Keep potential top candidate's parent node to try to get text direction of it later.
                parentOfTopCandidate = topCandidate.parentNode;
                var siblings = parentOfTopCandidate.children;

                for (var s = 0, sl = siblings.length; s < sl; s++) {
                    var sibling = siblings[s];
                    var append = false;

                    this.log("Looking at sibling node:", sibling, sibling.readability ? ("with score " + sibling.readability.contentScore) : "");
                    this.log("Sibling has score", sibling.readability ? sibling.readability.contentScore : "Unknown");

                    if (sibling === topCandidate) {
                        append = true;
                    } else {
                        var contentBonus = 0;

                        // Give a bonus if sibling nodes and top candidates have the example same classname
                        if (sibling.className === topCandidate.className && topCandidate.className !== "")
                            contentBonus += topCandidate.readability.contentScore * 0.2;

                        if (sibling.readability &&
                            ((sibling.readability.contentScore + contentBonus) >= siblingScoreThreshold)) {
                            append = true;
                        } else if (sibling.nodeName === "P") {
                            var linkDensity = this._getLinkDensity(sibling);
                            var nodeContent = this._getInnerText(sibling);
                            var nodeLength = nodeContent.length;

                            if (nodeLength > 80 && linkDensity < 0.25) {
                                append = true;
                            } else if (nodeLength < 80 && nodeLength > 0 && linkDensity === 0 &&
                                nodeContent.search(/\.( |$)/) !== -1) {
                                append = true;
                            }
                        }
                    }

                    if (append) {
                        this.log("Appending node:", sibling);

                        if (this.ALTER_TO_DIV_EXCEPTIONS.indexOf(sibling.nodeName) === -1) {
                            // We have a node that isn't a common block level element, like a form or td tag.
                            // Turn it into a div so it doesn't get filtered out later by accident.
                            this.log("Altering sibling:", sibling, "to div.");

                            sibling = this._setNodeTag(sibling, "DIV");
                        }

                        articleContent.appendChild(sibling);
                        // siblings is a reference to the children array, and
                        // sibling is removed from the array when we call appendChild().
                        // As a result, we must revisit this index since the nodes
                        // have been shifted.
                        s -= 1;
                        sl -= 1;
                    }
                }

                if (this._debug)
                    this.log("Article content pre-prep: " + articleContent.innerHTML);
                // So we have all of the content that we need. Now we clean it up for presentation.
                this._prepArticle(articleContent);
                if (this._debug)
                    this.log("Article content post-prep: " + articleContent.innerHTML);

                if (neededToCreateTopCandidate) {
                    // We already created a fake div thing, and there wouldn't have been any siblings left
                    // for the previous loop, so there's no point trying to create a new div, and then
                    // move all the children over. Just assign IDs and class names here. No need to append
                    // because that already happened anyway.
                    topCandidate.id = "readability-page-1";
                    topCandidate.className = "page";
                } else {
                    var div = doc.createElement("DIV");
                    div.id = "readability-page-1";
                    div.className = "page";
                    var children = articleContent.childNodes;
                    while (children.length) {
                        div.appendChild(children[0]);
                    }
                    articleContent.appendChild(div);
                }

                if (this._debug)
                    this.log("Article content after paging: " + articleContent.innerHTML);

                var parseSuccessful = true;

                // Now that we've gone through the full algorithm, check to see if
                // we got any meaningful content. If we didn't, we may need to re-run
                // grabArticle with different flags set. This gives us a higher likelihood of
                // finding the content, and the sieve approach gives us a higher likelihood of
                // finding the -right- content.
                var textLength = this._getInnerText(articleContent, true).length;
                if (textLength < this._charThreshold) {
                    parseSuccessful = false;
                    page.innerHTML = pageCacheHtml;

                    if (this._flagIsActive(this.FLAG_STRIP_UNLIKELYS)) {
                        this._removeFlag(this.FLAG_STRIP_UNLIKELYS);
                        this._attempts.push({ articleContent: articleContent, textLength: textLength });
                    } else if (this._flagIsActive(this.FLAG_WEIGHT_CLASSES)) {
                        this._removeFlag(this.FLAG_WEIGHT_CLASSES);
                        this._attempts.push({ articleContent: articleContent, textLength: textLength });
                    } else if (this._flagIsActive(this.FLAG_CLEAN_CONDITIONALLY)) {
                        this._removeFlag(this.FLAG_CLEAN_CONDITIONALLY);
                        this._attempts.push({ articleContent: articleContent, textLength: textLength });
                    } else {
                        this._attempts.push({ articleContent: articleContent, textLength: textLength });
                        // No luck after removing flags, just return the longest text we found during the different loops
                        this._attempts.sort(function (a, b) {
                            return b.textLength - a.textLength;
                        });

                        // But first check if we actually have something
                        if (!this._attempts[0].textLength) {
                            return null;
                        }

                        articleContent = this._attempts[0].articleContent;
                        parseSuccessful = true;
                    }
                }

                if (parseSuccessful) {
                    // Find out text direction from ancestors of final top candidate.
                    var ancestors = [parentOfTopCandidate, topCandidate].concat(this._getNodeAncestors(parentOfTopCandidate));
                    this._someNode(ancestors, function (ancestor) {
                        if (!ancestor.tagName)
                            return false;
                        var articleDir = ancestor.getAttribute("dir");
                        if (articleDir) {
                            this._articleDir = articleDir;
                            return true;
                        }
                        return false;
                    });
                    return articleContent;
                }
            }
        },

        /**
   * Check whether the input string could be a byline.
   * This verifies that the input is a string, and that the length
   * is less than 100 chars.
   *
   * @param possibleByline {string} - a string to check whether its a byline.
   * @return Boolean - whether the input string is a byline.
   */
        _isValidByline: function (byline) {
            if (typeof byline == "string" || byline instanceof String) {
                byline = byline.trim();
                return (byline.length > 0) && (byline.length < 100);
            }
            return false;
        },

        /**
   * Attempts to get excerpt and byline metadata for the article.
   *
   * @return Object with optional "excerpt" and "byline" properties
   */
        _getArticleMetadata: function () {
            var metadata = {};
            var values = {};
            var metaElements = this._doc.getElementsByTagName("meta");

            // property is a space-separated list of values
            var propertyPattern = /\s*(dc|dcterm|og|twitter)\s*:\s*(author|creator|description|title|site_name)\s*/gi;

            // name is a single value
            var namePattern = /^\s*(?:(dc|dcterm|og|twitter|weibo:(article|webpage))\s*[\.:]\s*)?(author|creator|description|title|site_name)\s*$/i;

            // Find description tags.
            this._forEachNode(metaElements, function (element) {
                var elementName = element.getAttribute("name");
                var elementProperty = element.getAttribute("property");
                var content = element.getAttribute("content");
                if (!content) {
                    return;
                }
                var matches = null;
                var name = null;

                if (elementProperty) {
                    matches = elementProperty.match(propertyPattern);
                    if (matches) {
                        for (var i = matches.length - 1; i >= 0; i--) {
                            // Convert to lowercase, and remove any whitespace
                            // so we can match below.
                            name = matches[i].toLowerCase().replace(/\s/g, "");
                            // multiple authors
                            values[name] = content.trim();
                        }
                    }
                }
                if (!matches && elementName && namePattern.test(elementName)) {
                    name = elementName;
                    if (content) {
                        // Convert to lowercase, remove any whitespace, and convert dots
                        // to colons so we can match below.
                        name = name.toLowerCase().replace(/\s/g, "").replace(/\./g, ":");
                        values[name] = content.trim();
                    }
                }
            });

            // get title
            metadata.title = values["dc:title"] ||
                values["dcterm:title"] ||
                values["og:title"] ||
                values["weibo:article:title"] ||
                values["weibo:webpage:title"] ||
                values["title"] ||
                values["twitter:title"];

            if (!metadata.title) {
                metadata.title = this._getArticleTitle();
            }

            // get author
            metadata.byline = values["dc:creator"] ||
                values["dcterm:creator"] ||
                values["author"];

            // get description
            metadata.excerpt = values["dc:description"] ||
                values["dcterm:description"] ||
                values["og:description"] ||
                values["weibo:article:description"] ||
                values["weibo:webpage:description"] ||
                values["description"] ||
                values["twitter:description"];

            // get site name
            metadata.siteName = values["og:site_name"];

            return metadata;
        },

        /**
   * Removes script tags from the document.
   *
   * @param Element
  **/
        _removeScripts: function (doc) {
            this._removeNodes(doc.getElementsByTagName("script"), function (scriptNode) {
                scriptNode.nodeValue = "";
                scriptNode.removeAttribute("src");
                return true;
            });
            this._removeNodes(doc.getElementsByTagName("noscript"));
        },

        /**
   * Check if this node has only whitespace and a single element with given tag
   * Returns false if the DIV node contains non-empty text nodes
   * or if it contains no element with given tag or more than 1 element.
   *
   * @param Element
   * @param string tag of child element
  **/
        _hasSingleTagInsideElement: function (element, tag) {
            // There should be exactly 1 element child with given tag
            if (element.children.length != 1 || element.children[0].tagName !== tag) {
                return false;
            }

            // And there should be no text nodes with real content
            return !this._someNode(element.childNodes, function (node) {
                return node.nodeType === this.TEXT_NODE &&
                    this.REGEXPS.hasContent.test(node.textContent);
            });
        },

        _isElementWithoutContent: function (node) {
            return node.nodeType === this.ELEMENT_NODE &&
                node.textContent.trim().length == 0 &&
                (node.children.length == 0 ||
                    node.children.length == node.getElementsByTagName("br").length + node.getElementsByTagName("hr").length);
        },

        /**
   * Determine whether element has any children block level elements.
   *
   * @param Element
   */
        _hasChildBlockElement: function (element) {
            return this._someNode(element.childNodes, function (node) {
                return this.DIV_TO_P_ELEMS.indexOf(node.tagName) !== -1 ||
                    this._hasChildBlockElement(node);
            });
        },

        /***
   * Determine if a node qualifies as phrasing content.
   * https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Content_categories#Phrasing_content
  **/
        _isPhrasingContent: function (node) {
            return node.nodeType === this.TEXT_NODE || this.PHRASING_ELEMS.indexOf(node.tagName) !== -1 ||
                ((node.tagName === "A" || node.tagName === "DEL" || node.tagName === "INS") &&
                    this._everyNode(node.childNodes, this._isPhrasingContent));
        },

        _isWhitespace: function (node) {
            return (node.nodeType === this.TEXT_NODE && node.textContent.trim().length === 0) ||
                (node.nodeType === this.ELEMENT_NODE && node.tagName === "BR");
        },

        /**
   * Get the inner text of a node - cross browser compatibly.
   * This also strips out any excess whitespace to be found.
   *
   * @param Element
   * @param Boolean normalizeSpaces (default: true)
   * @return string
  **/
        _getInnerText: function (e, normalizeSpaces) {
            normalizeSpaces = (typeof normalizeSpaces === "undefined") ? true : normalizeSpaces;
            var textContent = e.textContent.trim();

            if (normalizeSpaces) {
                return textContent.replace(this.REGEXPS.normalize, " ");
            }
            return textContent;
        },

        /**
   * Get the number of times a string s appears in the node e.
   *
   * @param Element
   * @param string - what to split on. Default is ","
   * @return number (integer)
  **/
        _getCharCount: function (e, s) {
            s = s || ",";
            return this._getInnerText(e).split(s).length - 1;
        },

        /**
   * Remove the style attribute on every e and under.
   * TODO: Test if getElementsByTagName(*) is faster.
   *
   * @param Element
   * @return void
  **/
        _cleanStyles: function (e) {
            if (!e || e.tagName.toLowerCase() === "svg")
                return;

            // Remove `style` and deprecated presentational attributes
            for (var i = 0; i < this.PRESENTATIONAL_ATTRIBUTES.length; i++) {
                e.removeAttribute(this.PRESENTATIONAL_ATTRIBUTES[i]);
            }

            if (this.DEPRECATED_SIZE_ATTRIBUTE_ELEMS.indexOf(e.tagName) !== -1) {
                e.removeAttribute("width");
                e.removeAttribute("height");
            }

            var cur = e.firstElementChild;
            while (cur !== null) {
                this._cleanStyles(cur);
                cur = cur.nextElementSibling;
            }
        },

        /**
   * Get the density of links as a percentage of the content
   * This is the amount of text that is inside a link divided by the total text in the node.
   *
   * @param Element
   * @return number (float)
  **/
        _getLinkDensity: function (element) {
            var textLength = this._getInnerText(element).length;
            if (textLength === 0)
                return 0;

            var linkLength = 0;

            // XXX implement _reduceNodeList?
            this._forEachNode(element.getElementsByTagName("a"), function (linkNode) {
                linkLength += this._getInnerText(linkNode).length;
            });

            return linkLength / textLength;
        },

        /**
   * Get an elements class/id weight. Uses regular expressions to tell if this
   * element looks good or bad.
   *
   * @param Element
   * @return number (Integer)
  **/
        _getClassWeight: function (e) {
            if (!this._flagIsActive(this.FLAG_WEIGHT_CLASSES))
                return 0;

            var weight = 0;

            // Look for a special classname
            if (typeof (e.className) === "string" && e.className !== "") {
                if (this.REGEXPS.negative.test(e.className))
                    weight -= 25;

                if (this.REGEXPS.positive.test(e.className))
                    weight += 25;
            }

            // Look for a special ID
            if (typeof (e.id) === "string" && e.id !== "") {
                if (this.REGEXPS.negative.test(e.id))
                    weight -= 25;

                if (this.REGEXPS.positive.test(e.id))
                    weight += 25;
            }

            return weight;
        },

        /**
   * Clean a node of all elements of type "tag".
   * (Unless it's a youtube/vimeo video. People love movies.)
   *
   * @param Element
   * @param string tag to clean
   * @return void
   **/
        _clean: function (e, tag) {
            var isEmbed = ["object", "embed", "iframe"].indexOf(tag) !== -1;

            this._removeNodes(e.getElementsByTagName(tag), function (element) {
                // Allow youtube and vimeo videos through as people usually want to see those.
                if (isEmbed) {
                    // First, check the elements attributes to see if any of them contain youtube or vimeo
                    for (var i = 0; i < element.attributes.length; i++) {
                        if (this.REGEXPS.videos.test(element.attributes[i].value)) {
                            return false;
                        }
                    }

                    // For embed with <object> tag, check inner HTML as well.
                    if (element.tagName === "object" && this.REGEXPS.videos.test(element.innerHTML)) {
                        return false;
                    }
                }

                return true;
            });
        },

        /**
   * Check if a given node has one of its ancestor tag name matching the
   * provided one.
   * @param  HTMLElement node
   * @param  String      tagName
   * @param  Number      maxDepth
   * @param  Function    filterFn a filter to invoke to determine whether this node 'counts'
   * @return Boolean
   */
        _hasAncestorTag: function (node, tagName, maxDepth, filterFn) {
            maxDepth = maxDepth || 3;
            tagName = tagName.toUpperCase();
            var depth = 0;
            while (node.parentNode) {
                if (maxDepth > 0 && depth > maxDepth)
                    return false;
                if (node.parentNode.tagName === tagName && (!filterFn || filterFn(node.parentNode)))
                    return true;
                node = node.parentNode;
                depth++;
            }
            return false;
        },

        /**
   * Return an object indicating how many rows and columns this table has.
   */
        _getRowAndColumnCount: function (table) {
            var rows = 0;
            var columns = 0;
            var trs = table.getElementsByTagName("tr");
            for (var i = 0; i < trs.length; i++) {
                var rowspan = trs[i].getAttribute("rowspan") || 0;
                if (rowspan) {
                    rowspan = parseInt(rowspan, 10);
                }
                rows += (rowspan || 1);

                // Now look for column-related info
                var columnsInThisRow = 0;
                var cells = trs[i].getElementsByTagName("td");
                for (var j = 0; j < cells.length; j++) {
                    var colspan = cells[j].getAttribute("colspan") || 0;
                    if (colspan) {
                        colspan = parseInt(colspan, 10);
                    }
                    columnsInThisRow += (colspan || 1);
                }
                columns = Math.max(columns, columnsInThisRow);
            }
            return { rows: rows, columns: columns };
        },

        /**
   * Look for 'data' (as opposed to 'layout') tables, for which we use
   * similar checks as
   * https://dxr.mozilla.org/mozilla-central/rev/71224049c0b52ab190564d3ea0eab089a159a4cf/accessible/html/HTMLTableAccessible.cpp#920
   */
        _markDataTables: function (root) {
            var tables = root.getElementsByTagName("table");
            for (var i = 0; i < tables.length; i++) {
                var table = tables[i];
                var role = table.getAttribute("role");
                if (role == "presentation") {
                    table._readabilityDataTable = false;
                    continue;
                }
                var datatable = table.getAttribute("datatable");
                if (datatable == "0") {
                    table._readabilityDataTable = false;
                    continue;
                }
                var summary = table.getAttribute("summary");
                if (summary) {
                    table._readabilityDataTable = true;
                    continue;
                }

                var caption = table.getElementsByTagName("caption")[0];
                if (caption && caption.childNodes.length > 0) {
                    table._readabilityDataTable = true;
                    continue;
                }

                // If the table has a descendant with any of these tags, consider a data table:
                var dataTableDescendants = ["col", "colgroup", "tfoot", "thead", "th"];
                var descendantExists = function (tag) {
                    return !!table.getElementsByTagName(tag)[0];
                };
                if (dataTableDescendants.some(descendantExists)) {
                    this.log("Data table because found data-y descendant");
                    table._readabilityDataTable = true;
                    continue;
                }

                // Nested tables indicate a layout table:
                if (table.getElementsByTagName("table")[0]) {
                    table._readabilityDataTable = false;
                    continue;
                }

                var sizeInfo = this._getRowAndColumnCount(table);
                if (sizeInfo.rows >= 10 || sizeInfo.columns > 4) {
                    table._readabilityDataTable = true;
                    continue;
                }
                // Now just go by size entirely:
                table._readabilityDataTable = sizeInfo.rows * sizeInfo.columns > 10;
            }
        },

        /* convert images and figures that have properties like data-src into images that can be loaded without JS */
        _fixLazyImages: function (root) {
            this._forEachNode(this._getAllNodesWithTag(root, ["img", "picture", "figure"]), function (elem) {
                // also check for "null" to work around https://github.com/jsdom/jsdom/issues/2580
                if ((!elem.src && (!elem.srcset || elem.srcset == "null")) || elem.className.toLowerCase().indexOf("lazy") !== -1) {
                    for (var i = 0; i < elem.attributes.length; i++) {
                        var attr = elem.attributes[i];
                        if (attr.name === "src" || attr.name === "srcset") {
                            continue;
                        }
                        var copyTo = null;
                        if (/\.(jpg|jpeg|png|webp)\s+\d/.test(attr.value)) {
                            copyTo = "srcset";
                        } else if (/^\s*\S+\.(jpg|jpeg|png|webp)\S*\s*$/.test(attr.value)) {
                            copyTo = "src";
                        }
                        if (copyTo) {
                            //if this is an img or picture, set the attribute directly
                            if (elem.tagName === "IMG" || elem.tagName === "PICTURE") {
                                elem.setAttribute(copyTo, attr.value);
                            } else if (elem.tagName === "FIGURE" && !this._getAllNodesWithTag(elem, ["img", "picture"]).length) {
                                //if the item is a <figure> that does not contain an image or picture, create one and place it inside the figure
                                //see the nytimes-3 testcase for an example
                                var img = this._doc.createElement("img");
                                img.setAttribute(copyTo, attr.value);
                                elem.appendChild(img);
                            }
                        }
                    }
                }
            });
        },

        /**
   * Clean an element of all tags of type "tag" if they look fishy.
   * "Fishy" is an algorithm based on content length, classnames, link density, number of images & embeds, etc.
   *
   * @return void
   **/
        _cleanConditionally: function (e, tag) {
            if (!this._flagIsActive(this.FLAG_CLEAN_CONDITIONALLY))
                return;

            var isList = tag === "ul" || tag === "ol";

            // Gather counts for other typical elements embedded within.
            // Traverse backwards so we can remove nodes at the same time
            // without effecting the traversal.
            //
            // TODO: Consider taking into account original contentScore here.
            this._removeNodes(e.getElementsByTagName(tag), function (node) {
                // First check if this node IS data table, in which case don't remove it.
                var isDataTable = function (t) {
                    return t._readabilityDataTable;
                };

                if (tag === "table" && isDataTable(node)) {
                    return false;
                }

                // Next check if we're inside a data table, in which case don't remove it as well.
                if (this._hasAncestorTag(node, "table", -1, isDataTable)) {
                    return false;
                }

                var weight = this._getClassWeight(node);
                var contentScore = 0;

                this.log("Cleaning Conditionally", node);

                if (weight + contentScore < 0) {
                    return true;
                }

                if (this._getCharCount(node, ",") < 10) {
                    // If there are not very many commas, and the number of
                    // non-paragraph elements is more than paragraphs or other
                    // ominous signs, remove the element.
                    var p = node.getElementsByTagName("p").length;
                    var img = node.getElementsByTagName("img").length;
                    var li = node.getElementsByTagName("li").length - 100;
                    var input = node.getElementsByTagName("input").length;

                    var embedCount = 0;
                    var embeds = this._concatNodeLists(
                        node.getElementsByTagName("object"),
                        node.getElementsByTagName("embed"),
                        node.getElementsByTagName("iframe"));

                    for (var i = 0; i < embeds.length; i++) {
                        // If this embed has attribute that matches video regex, don't delete it.
                        for (var j = 0; j < embeds[i].attributes.length; j++) {
                            if (this.REGEXPS.videos.test(embeds[i].attributes[j].value)) {
                                return false;
                            }
                        }

                        // For embed with <object> tag, check inner HTML as well.
                        if (embeds[i].tagName === "object" && this.REGEXPS.videos.test(embeds[i].innerHTML)) {
                            return false;
                        }

                        embedCount++;
                    }

                    var linkDensity = this._getLinkDensity(node);
                    var contentLength = this._getInnerText(node).length;

                    var haveToRemove =
                        (img > 1 && p / img < 0.5 && !this._hasAncestorTag(node, "figure")) ||
                        (!isList && li > p) ||
                        (input > Math.floor(p / 3)) ||
                        (!isList && contentLength < 25 && (img === 0 || img > 2) && !this._hasAncestorTag(node, "figure")) ||
                        (!isList && weight < 25 && linkDensity > 0.2) ||
                        (weight >= 25 && linkDensity > 0.5) ||
                        ((embedCount === 1 && contentLength < 75) || embedCount > 1);
                    return haveToRemove;
                }
                return false;
            });
        },

        /**
   * Clean out elements that match the specified conditions
   *
   * @param Element
   * @param Function determines whether a node should be removed
   * @return void
   **/
        _cleanMatchedNodes: function (e, filter) {
            var endOfSearchMarkerNode = this._getNextNode(e, true);
            var next = this._getNextNode(e);
            while (next && next != endOfSearchMarkerNode) {
                if (filter.call(this, next, next.className + " " + next.id)) {
                    next = this._removeAndGetNext(next);
                } else {
                    next = this._getNextNode(next);
                }
            }
        },

        /**
   * Clean out spurious headers from an Element. Checks things like classnames and link density.
   *
   * @param Element
   * @return void
  **/
        _cleanHeaders: function (e) {
            for (var headerIndex = 1; headerIndex < 3; headerIndex += 1) {
                this._removeNodes(e.getElementsByTagName("h" + headerIndex), function (header) {
                    return this._getClassWeight(header) < 0;
                });
            }
        },

        _flagIsActive: function (flag) {
            return (this._flags & flag) > 0;
        },

        _removeFlag: function (flag) {
            this._flags = this._flags & ~flag;
        },

        _isProbablyVisible: function (node) {
            return (!node.style || node.style.display != "none")
                && !node.hasAttribute("hidden")
                && (!node.hasAttribute("aria-hidden") || node.getAttribute("aria-hidden") != "true");
        },

        /**
   * Runs readability.
   *
   * Workflow:
   *  1. Prep the document by removing script tags, css, etc.
   *  2. Build readability's DOM tree.
   *  3. Grab the article content from the current dom tree.
   *  4. Replace the current DOM tree with the new one.
   *  5. Read peacefully.
   *
   * @return void
   **/
        parse: function () {
            // Avoid parsing too large documents, as per configuration option
            if (this._maxElemsToParse > 0) {
                var numTags = this._doc.getElementsByTagName("*").length;
                if (numTags > this._maxElemsToParse) {
                    throw new Error("Aborting parsing document; " + numTags + " elements found");
                }
            }

            // Remove script tags from the document.
            this._removeScripts(this._doc);

            this._prepDocument();

            var metadata = this._getArticleMetadata();
            this._articleTitle = metadata.title;

            var articleContent = this._grabArticle();
            if (!articleContent)
                return null;

            this.log("Grabbed: " + articleContent.innerHTML);

            this._postProcessContent(articleContent);

            // If we haven't found an excerpt in the article's metadata, use the article's
            // first paragraph as the excerpt. This is used for displaying a preview of
            // the article's content.
            if (!metadata.excerpt) {
                var paragraphs = articleContent.getElementsByTagName("p");
                if (paragraphs.length > 0) {
                    metadata.excerpt = paragraphs[0].textContent.trim();
                }
            }

            var textContent = articleContent.textContent;
            return {
                title: this._articleTitle,
                byline: metadata.byline || this._articleByline,
                dir: this._articleDir,
                content: articleContent.innerHTML,
                textContent: textContent,
                length: textContent.length,
                excerpt: metadata.excerpt,
                siteName: metadata.siteName || this._articleSiteName
            };
        }
    };

    if (typeof module === "object") {
        module.exports = Readability;
    }



})();