safari-reader.js

/*
 * Copyright © 2010 Apple Inc. All rights reserved.
 * DOWNLOAD FROM: http://blog.manbolo.com/2013/03/18/safari-reader-source-code 
 */
const ReaderMinimumScore = 1600;
const ReaderMinimumAdvantage = 15;
const ArticleMinimumScoreDensity = 4.25;
var BlacklistedHostsAllowedPathPrefixesMap = {};
BlacklistedHostsAllowedPathPrefixesMap["www.apple.com"] = ["/pr/"];
const CandidateMinimumWidth = 280;
const CandidateMinimumHeight = 295;
const CandidateMinimumArea = 170000;
const CandidateMaximumTop = 1300;
const CandidateMinimumWidthPortionForIndicatorElements = 0.5;
const CandidateMinumumListItemLineCount = 4;
const CandidateTagNamesToIgnore = {
    "A": 1,
    "BODY": 1,
    "EMBED": 1,
    "FORM": 1,
    "HTML": 1,
    "IFRAME": 1,
    "OBJECT": 1,
    "OPTION": 1,
    "SCRIPT": 1,
    "STYLE": 1,
    "svg": 1
};
const CandidateTagNamesToIgnoreDescendantsOf = {
    "DD": 1,
    "DT": 1,
    "LI": 1,
    "OL": 1,
    "UL": 1
};

function shouldIgnoreElementBySelfOrAncestorTagName(element) {
    if (CandidateTagNamesToIgnore[element.tagName])
        return true;
    for (var ancestor = element; ancestor; ancestor = ancestor.parentNode)
        if (CandidateTagNamesToIgnoreDescendantsOf[ancestor.tagName])
            return true;
    return false;
}
const PrependedArticleCandidateMinimumHeight = 50;
const AppendedArticleCandidateMinimumHeight = 200;
const AppendedArticleCandidateMaximumVerticalDistanceFromArticle = 150;
const StylisticClassNames = {
    "justfy": 1,
    "justify": 1,
    "left": 1,
    "right": 1,
    "small": 1
};
const CommentRegEx = /comment|meta|footer|footnote/;
const CommentMatchPenalty = 0.5;
const ArticleRegEx = /(?:(?:^|\\s)(?:post|hentry|entry[-]?(?:content|text|body)?|article[-]?(?:content|text|body)?)(?:\\s|$))/;
const ArticleMatchBonus = 0.5;
const DensityExcludedElementSelector = "#disqus_thread, #comments, .userComments";
const AttributesToRemoveRegEx = /^on|^id$|^class$|^style$/;
const PositiveRegEx = /article|body|content|entry|hentry|page|pagination|post|text/i;
const NegativeRegEx = /breadcrumb|combx|comment|contact|disqus|foot|footer|footnote|link|media|meta|mod-conversations|promo|related|scroll|share|shoutbox|sidebar|social|sponsor|tags|toolbox|widget/i;
const MinimumAverageDistanceBetweenHRElements = 400;
const MinimumAverageDistanceBetweenHeaderElements = 400;
const PortionOfCandidateHeightToIgnoreForHeaderCheck = 0.1;
const ScoreMultiplierForChineseJapaneseKorean = 3;
const MinimumContentImageHeight = 200;
const MinimumContentImageWidthToArticleWidthRatio = 0.5;
const MaximumContentImageAreaToArticleAreaRatio = 0.2;
const LinkContinueMatchRegEx = /continue/gi;
const LinkNextMatchRegEx = /next/gi;
const LinkPageMatchRegEx = /page/gi;
const LinkListItemBonus = 5;
const LinkPageMatchBonus = 10;
const LinkNextMatchBonus = 15;
const LinkContinueMatchBonus = 15;
const LinkNextOrdinalValueBase = 3;
const LinkMismatchValueBase = 2;
const LinkMatchWeight = 200;
const LinkMaxVerticalDistanceFromArticle = 200;
const LinkVerticalDistanceFromArticleWeight = 150;
const LinkCandidateXPathQuery = "descendant-or-self::*[(not(@id) or (@id!='disqus_thread' and @id!='comments')) and (not(@class) or @class!='userComments')]/a";
const LinkDateRegex = /\D(?:\d\d(?:\d\d)?[\-\/](?:10|11|12|0?[1-9])[\-\/](?:30|31|[12][0-9]|0?[1-9])|\d\d(?:\d\d)?\/(?:10|11|12|0[1-9])|(?:10|11|12|0?[1-9])\-(?:30|31|[12][0-9]|0?[1-9])\-\d\d(?:\d\d)?|(?:30|31|[12][0-9]|0?[1-9])\-(?:10|11|12|0?[1-9])\-\d\d(?:\d\d)?)\D/;
const LinkURLSearchParameterKeyMatchRegex = /(page|^p$|^pg$)/i;
const LinkURLPageSlashNumberMatchRegex = /\/.*page.*\/\d+/i;
const LinkURLSlashDigitEndMatchRegex = /\/\d+\/?$/;
const LinkURLArchiveSlashDigitEndMatchRegex = /archives?\/\d+\/?$/;
const LinkURLBadSearchParameterKeyMatchRegex = /feed/;
const LinkURLSemanticMatchBonus = 100;
const LinkMinimumURLSimilarityRatio = 0.75;
const HeaderMinimumDistanceFromArticleTop = 200;
const HeaderLevenshteinDistanceToLengthRatio = 0.75;
const FloatMinimumHeight = 130;
const ImageSizeTiny = 32;
const ImageWidthToParentWidthRatio = .5;
const AnchorImageMinimumWidth = 100;
const AnchorImageMinimumHeight = 100;
const BaseFontSize = 16;
const BaseLineHeightRatio = 1.125;
const MaximumExactIntegralValue = 9007199254740992;
const TitleCandidateDepthScoreMultiplier = 0.1;
const DocumentPositionDisconnected = 0x01;
const DocumentPositionPreceding = 0x02;
const DocumentPositionFollowing = 0x04;
const DocumentPositionContains = 0x08;
const DocumentPositionContainedBy = 0x10;

function characterNeedsScoreMultiplier(character) {
    if (!character || character.length == 0)
        return false;
    var characterCode = character.charCodeAt(0);
    if (characterCode > 11904 && characterCode < 12031)
        return true;
    if (characterCode > 12352 && characterCode < 12543)
        return true;
    if (characterCode > 12736 && characterCode < 19903)
        return true;
    if (characterCode > 19968 && characterCode < 40959)
        return true;
    if (characterCode > 44032 && characterCode < 55215)
        return true;
    if (characterCode > 63744 && characterCode < 64255)
        return true;
    if (characterCode > 65072 && characterCode < 65103)
        return true;
    if (characterCode > 131072 && characterCode < 173791)
        return true;
    if (characterCode > 194560 && characterCode < 195103)
        return true;
    return false;
}

function domDistance(elementA, elementB, distanceCap) {
    var ancestorsA = [];
    var node = elementA;
    while (node) {
        ancestorsA.unshift(node);
        node = node.parentNode;
    }
    var ancestorsB = [];
    node = elementB;
    while (node) {
        ancestorsB.unshift(node);
        node = node.parentNode;
    }
    var shallowerDepth = Math.min(ancestorsA.length, ancestorsB.length);
    var domDistance = Math.abs(ancestorsA.length - ancestorsB.length);
    for (var i = shallowerDepth; i >= 0; i--) {
        if (ancestorsA[i] === ancestorsB[i])
            break;
        domDistance += 2;
        if (distanceCap && domDistance >= distanceCap)
            return distanceCap;
    }
    return domDistance;
}

function fontSizeFromComputedStyle(style, fallbackSize) {
    var fontSize = parseInt(style.fontSize);
    if (isNaN(fontSize))
        fontSize = fallbackSize ? fallbackSize : BaseFontSize;
    return fontSize;
}

function contentTextStyleForNode(contentDocument, node, searchInReverse) {
    function getComputedStyleIfNodeIsBodyText(textNode) {
        if (isNodeWhitespace(textNode))
            return null;
        var style = getComputedStyle(textNode.parentNode);
        if (style.float !== "none")
            return null;
        return style;
    }
    var nonHeaderTextXPathQuery = "descendant::text()[not(parent::h1) and not(parent::h2) and not(parent::h3) and not(parent::h4) and not(parent::h5) and not(parent::h6)]";
    var articleTextNodes = contentDocument.evaluate(nonHeaderTextXPathQuery, node, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
    if (searchInReverse) {
        for (var nodeIndex = articleTextNodes.snapshotLength - 1; nodeIndex >= 0; nodeIndex--) {
            var style = getComputedStyleIfNodeIsBodyText(articleTextNodes.snapshotItem(nodeIndex));
            if (style)
                return style;
        }
    } else {
        for (var nodeIndex = 0; nodeIndex < articleTextNodes.snapshotLength; nodeIndex++) {
            var style = getComputedStyleIfNodeIsBodyText(articleTextNodes.snapshotItem(nodeIndex));
            if (style)
                return style;
        }
    }
    return null;
}

function isNodeWhitespace(node) {
    if (!node || node.nodeType !== Node.TEXT_NODE)
        return false;
    return !/\S/.test(node.data);
}

function removeWhitespace(string) {
    return string.replace(/\s+/g, '');
}

function isElementNode(node) {
    if (node && node.nodeType === Node.ELEMENT_NODE)
        return true;
    return false;
}

function isElementVisible(element) {
    var style = getComputedStyle(element);
    if (style.visibility !== "visible" || style.display === "none")
        return false;
    if (!cachedElementBoundingRect(element).height)
        return false;
    return true;
}

function elementDepth(element) {
    var depth = 0;
    while (element) {
        element = element.parentElement;
        depth++;
    }
    return depth;
}

function elementHasAncestorWithTagName(element, tagName) {
    var node = element;
    while (node.parentNode) {
        node = node.parentNode;
        if (node.tagName === tagName)
            return true;
    }
    return false;
}

function cachedElementBoundingRect(element) {
    if (element._cachedElementBoundingRect)
        return element._cachedElementBoundingRect;
    var rect = element.getBoundingClientRect();
    ReaderArticleFinderJS._elementsWithCachedBoundingRects.push(element);
    if (!ReaderArticleFinderJS._cachedScrollY && !ReaderArticleFinderJS._cachedScrollY) {
        element._cachedElementBoundingRect = rect;
        return element._cachedElementBoundingRect;
    }
    element._cachedElementBoundingRect = {
        top: rect.top + ReaderArticleFinderJS._cachedScrollY,
        right: rect.right - ReaderArticleFinderJS._cachedScrollX,
        bottom: rect.bottom - ReaderArticleFinderJS._cachedScrollY,
        left: rect.left + ReaderArticleFinderJS._cachedScrollX,
        width: rect.width,
        height: rect.height
    };
    return element._cachedElementBoundingRect;
}

function clearCachedElementBoundingRects() {
    var elementsWithRects = ReaderArticleFinderJS._elementsWithCachedBoundingRects;
    var elementCount = elementsWithRects.length;
    for (var i = 0; i < elementCount; i++)
        elementsWithRects[i]._cachedElementBoundingRect = null;
    ReaderArticleFinderJS._elementsWithCachedBoundingRects = [];
}

function innerTextOrTextContent(element) {
    var text = element.innerText;
    if (!text)
        text = element.textContent;
    return text;
}

function levenshteinDistance(s, t) {
    var m = s.length;
    var n = t.length;
    var d = new Array(m + 1);
    for (var i = 0; i < m + 1; i++) {
        d[i] = new Array(n + 1);
        d[i][0] = i;
    }
    for (var j = 0; j < n + 1; j++)
        d[0][j] = j;
    for (var j = 1; j < n + 1; j++) {
        for (var i = 1; i < m + 1; i++) {
            if (s[i - 1] === t[j - 1])
                d[i][j] = d[i - 1][j - 1];
            else {
                var deletion = d[i - 1][j] + 1;
                var insertion = d[i][j - 1] + 1;
                var substitution = d[i - 1][j - 1] + 1;
                d[i][j] = Math.min(deletion, insertion, substitution);
            }
        }
    }
    return d[m][n];
}

function stringSimilarity(s, t) {
    var maxLength = Math.max(s.length, t.length);
    return maxLength ? (maxLength - levenshteinDistance(s, t)) / maxLength : 0;
}
CandidateElement = function (element, contentDocument) {
    this.element = element
    this.contentDocument = contentDocument;
    this.textNodes = this.usableTextNodesInElement(this.element);
    this.rawScore = this.calculateRawScore();
    this.regExBonusMultiplier = this.calculateRegExBonus();
    this.languageScoreMultiplier = 0;
    this.depthInDocument = 0;
}
CandidateElement.extraArticleCandidateIfElementIsViable = function extraArticleCandidateIfElementIsViable(element, selectedArticle, contentDocument, isPrepended) {
    const InlineTextContainerTagNames = "a, b, strong, i, em, u, span";
    var documentRect = cachedElementBoundingRect(element);
    var selectedArticleRect = cachedElementBoundingRect(selectedArticle.element);
    if ((isPrepended && documentRect.height < PrependedArticleCandidateMinimumHeight) || (!isPrepended && documentRect.height < AppendedArticleCandidateMinimumHeight)) {
        if (element.childElementCount && element.querySelectorAll("*").length != element.querySelectorAll(InlineTextContainerTagNames).length)
            return null;
    }
    if (isPrepended) {
        if (documentRect.bottom > selectedArticleRect.top)
            return null;
    } else {
        if (documentRect.top < selectedArticleRect.bottom)
            return null;
    }
    if (!isPrepended) {
        var distanceFromArticle = documentRect.top - selectedArticleRect.bottom;
        console.assert(distanceFromArticle > 0, "An appended article node must be below the article");
        if (distanceFromArticle > AppendedArticleCandidateMaximumVerticalDistanceFromArticle)
            return null;
    }
    var maxDelta = 0.1 * selectedArticleRect.width;
    if (Math.abs(documentRect.left - selectedArticleRect.left) > maxDelta || Math.abs(documentRect.right - selectedArticle.right) > maxDelta)
        return null;
    var candidate = new CandidateElement(element, contentDocument);
    candidate.isPrepended = isPrepended;
    return candidate;
}
CandidateElement.candidateIfElementIsViable = function candidateIfElementIsViable(element, contentDocument, isForSimilarClass) {
    var documentRect = cachedElementBoundingRect(element);
    if (isForSimilarClass)
        return new CandidateElement(element, contentDocument);
    if (documentRect.width < CandidateMinimumWidth || documentRect.height < CandidateMinimumHeight)
        return null;
    if (documentRect.width * documentRect.height < CandidateMinimumArea)
        return null;
    if (documentRect.top > CandidateMaximumTop)
        return null;
    if (CandidateElement.candidateElementAdjustedHeight(element) < CandidateMinimumHeight)
        return null;
    return new CandidateElement(element, contentDocument);
}
CandidateElement.candidateElementAdjustedHeight = function candidateElementAdjustedHeight(element) {
    var documentRect = cachedElementBoundingRect(element);
    var adjustedHeight = documentRect.height;
    var indicatorElements = element.querySelectorAll("form");
    for (var i = 0; i < indicatorElements.length; i++) {
        var indicatorElement = indicatorElements[i];
        var indicatorRect = cachedElementBoundingRect(indicatorElement);
        if (indicatorRect.width > documentRect.width * CandidateMinimumWidthPortionForIndicatorElements)
            adjustedHeight -= indicatorRect.height;
    }
    var listContainers = element.querySelectorAll("ol, ul");
    var listContainersCount = listContainers.length;
    var lastListContainerSubstracted = null;
    for (var i = 0; i < listContainersCount; i++) {
        var listContainer = listContainers[i];
        if (lastListContainerSubstracted && lastListContainerSubstracted.compareDocumentPosition(listContainer) & DocumentPositionContainedBy)
            continue;
        var listItems = listContainer.querySelectorAll("li");
        var listItemCount = listItems.length;
        var listRect = cachedElementBoundingRect(listContainer);
        if (!listItemCount) {
            adjustedHeight -= listRect.height;
            continue;
        }
        var averageListItemHeight = listRect.height / listItemCount;
        var firstListItemStyle = getComputedStyle(listItems[0]);
        var listLineHeight = parseInt(firstListItemStyle.lineHeight);
        if (isNaN(listLineHeight)) {
            var listFontSize = fontSizeFromComputedStyle(firstListItemStyle);
            listLineHeight = listFontSize * BaseLineHeightRatio;
        }
        if (listRect.width > documentRect.width * CandidateMinimumWidthPortionForIndicatorElements && ((averageListItemHeight / listLineHeight) < CandidateMinumumListItemLineCount)) {
            adjustedHeight -= listRect.height;
            lastListContainerSubstracted = listContainer;
        }
    }
    return adjustedHeight;
}
CandidateElement.prototype = {
    calculateRawScore: function calculateRawScore() {
        var score = 0;
        var textNodes = this.textNodes;
        for (var i = 0; i < textNodes.length; i++)
            score += this.rawScoreForTextNode(textNodes[i]);
        return score;
    },
    calculateRegExBonus: function calculateRegExBonus() {
        var regExBonusMultiplier = 1;
        for (var currentElement = this.element; currentElement; currentElement = currentElement.parentElement) {
            var currentElementId = currentElement.getAttribute("id");
            if (currentElementId) {
                if (ArticleRegEx.test(currentElementId))
                    regExBonusMultiplier += ArticleMatchBonus;
                if (CommentRegEx.test(currentElementId))
                    regExBonusMultiplier -= CommentMatchPenalty;
            }
            var currentElementClassName = currentElement.className;
            if (currentElementClassName && typeof currentElementClassName === "string") {
                if (ArticleRegEx.test(currentElementClassName))
                    regExBonusMultiplier += ArticleMatchBonus;
                if (CommentRegEx.test(currentElementClassName))
                    regExBonusMultiplier -= CommentMatchPenalty;
            }
        }
        return regExBonusMultiplier;
    },
    calculateLanguageScoreMultiplier: function calculateLanguageScoreMultiplier() {
        if (this.languageScoreMultiplier != 0)
            return;
        if (this.textNodes && this.textNodes.length > 0) {
            var numCharactersThatNeedMultiplier = 0;
            var textString = this.textNodes[0].nodeValue.trim();
            var length = Math.min(textString.length, 10);
            for (var i = 0; i < length; i++) {
                if (characterNeedsScoreMultiplier(textString[i]))
                    numCharactersThatNeedMultiplier++;
            }
            if (numCharactersThatNeedMultiplier >= length / 2) {
                this.languageScoreMultiplier = ScoreMultiplierForChineseJapaneseKorean;
                return;
            }
        }
        this.languageScoreMultiplier = 1;
    },
    depth: function depth() {
        if (!this.depthInDocument)
            this.depthInDocument = elementDepth(this.element);
        return this.depthInDocument;
    },
    finalScore: function finalScore() {
        this.calculateLanguageScoreMultiplier();
        return this.basicScore() * this.languageScoreMultiplier;
    },
    basicScore: function basicScore() {
        return this.rawScore * this.regExBonusMultiplier;
    },
    scoreDensity: function scoreDensity() {
        var ignoredArea = 0;
        var ignoredElement = this.element.querySelector(DensityExcludedElementSelector);
        if (ignoredElement)
            ignoredArea = ignoredElement.clientWidth * ignoredElement.clientHeight;
        var articleArea = cachedElementBoundingRect(this.element).width * cachedElementBoundingRect(this.element).height;
        var maximumImageArea = articleArea * MaximumContentImageAreaToArticleAreaRatio;
        var imageMinimumWidth = cachedElementBoundingRect(this.element).width * MinimumContentImageWidthToArticleWidthRatio;
        var imageElements = this.element.querySelectorAll("img");
        var imageCount = imageElements.length;
        for (var i = 0; i < imageCount; i++) {
            var imageRect = cachedElementBoundingRect(imageElements[i]);
            if (imageRect.width >= imageMinimumWidth && imageRect.height > MinimumContentImageHeight) {
                var imageArea = imageRect.width * imageRect.height;
                if (imageArea < maximumImageArea)
                    ignoredArea += imageArea;
            }
        }
        var score = this.basicScore();
        var area = articleArea - ignoredArea;
        var numberOfTextNodes = this.textNodes.length;
        var numberOfCountedTextNodes = 0;
        var sumOfFontSizes = 0;
        for (var i = 0; i < numberOfTextNodes; i++) {
            var parentNode = this.textNodes[i].parentNode;
            console.assert(parentNode, "parentNode of this.textNodes[i] cannot be nil");
            if (parentNode) {
                sumOfFontSizes += fontSizeFromComputedStyle(getComputedStyle(parentNode));
                numberOfCountedTextNodes++;
            }
        }
        var averageFontSize = BaseFontSize;
        if (numberOfCountedTextNodes)
            averageFontSize = sumOfFontSizes /= numberOfCountedTextNodes;
        this.calculateLanguageScoreMultiplier();
        return (score / area * 1000) * (averageFontSize / BaseFontSize) * this.languageScoreMultiplier;
    },
    usableTextNodesInElement: function usableTextNodesInElement(element) {
        var textNodes = [];
        if (!element)
            return textNodes;
        const tagNamesToIgnore = {
            "A": 1,
            "DD": 1,
            "DT": 1,
            "NOSCRIPT": 1,
            "OL": 1,
            "OPTION": 1,
            "PRE": 1,
            "SCRIPT": 1,
            "STYLE": 1,
            "TD": 1,
            "UL": 1
        };
        var xPathQuery = "text()|*/text()|*/a/text()|*/li/text()|*/span/text()|*/em/text()|*/i/text()|*/strong/text()|*/b/text()|*/font/text()|blockquote/*/text()|div[count(./p)=count(./*)]/p/text()";
        var xPathResults = this.contentDocument.evaluate(xPathQuery, element, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
        for (var i = 0; i < xPathResults.snapshotLength; i++) {
            var textNode = xPathResults.snapshotItem(i);
            if (tagNamesToIgnore[textNode.parentNode.tagName])
                continue;
            if (isNodeWhitespace(textNode))
                continue;
            textNodes.push(textNode);
        }
        return textNodes;
    },
    addTextNodesFromCandidateElement: function addTextNodesFromCandidateElement(otherCandidateElement) {
        for (var j = 0; j < this.textNodes.length; j++)
            this.textNodes[j].alreadyCounted = true;
        var otherCandidateElementTextNodes = otherCandidateElement.textNodes;
        for (var j = 0; j < otherCandidateElementTextNodes.length; j++) {
            if (!otherCandidateElementTextNodes[j].alreadyCounted)
                this.textNodes.push(otherCandidateElementTextNodes[j]);
        }
        for (var j = 0; j < this.textNodes.length; j++)
            this.textNodes[j].alreadyCounted = null;
        this.rawScore = this.calculateRawScore();
    },
    rawScoreForTextNode: function rawScoreForTextNode(textNode) {
        const TextNodeMinimumLength = 20;
        const TextNodeLengthPower = 1.25;
        if (!textNode)
            return 0;
        var length = textNode.length;
        if (length < TextNodeMinimumLength)
            return 0;
        var ancestor = textNode.parentNode;
        if (!isElementVisible(ancestor))
            return 0;
        var multiplier = 1;
        while (ancestor && ancestor != this.element) {
            multiplier -= 0.1;
            ancestor = ancestor.parentNode;
        }
        return Math.pow(length * multiplier, TextNodeLengthPower);
    },
    shouldDisqualifyDueToScoreDensity: function shouldDisqualifyDueToScoreDensity() {
        if (this.scoreDensity() < ArticleMinimumScoreDensity)
            return true;
        return false;
    },
    shouldDisqualifyDueToHorizontalRuleDensity: function shouldDisqualifyDueToHorizontalRuleDensity() {
        var horizontalRules = this.element.querySelectorAll("hr");
        var numberOfHRs = horizontalRules.length;
        var numberOfHRsToCount = 0;
        var elementRect = cachedElementBoundingRect(this.element);
        var minimumWidthToCount = elementRect.width * 0.70;
        for (var i = 0; i < numberOfHRs; i++) {
            if (horizontalRules[i].clientWidth > minimumWidthToCount)
                numberOfHRsToCount++;
        }
        if (numberOfHRsToCount) {
            var averageDistanceBetweenHRs = elementRect.height / numberOfHRsToCount;
            if (averageDistanceBetweenHRs < MinimumAverageDistanceBetweenHRElements)
                return true;
        }
        return false;
    },
    shouldDisqualifyDueToHeaderDensity: function shouldDisqualifyDueToHeaderDensity() {
        var headerLinksXPathQuery = "(h1|h2|h3|h4|h5|h6|*/h1|*/h2|*/h3|*/h4|*/h5|*/h6)[a]";
        var headerLinkResults = this.contentDocument.evaluate(headerLinksXPathQuery, this.element, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
        if (headerLinkResults.snapshotLength > 2) {
            var numberOfHeadersToCount = 0;
            var elementRect = cachedElementBoundingRect(this.element);
            var topBottomIgnoreDistance = elementRect.height * PortionOfCandidateHeightToIgnoreForHeaderCheck;
            for (var i = 0; i < headerLinkResults.snapshotLength; i++) {
                var header = headerLinkResults.snapshotItem(i);
                var headerRect = cachedElementBoundingRect(header);
                if (headerRect.top - elementRect.top > topBottomIgnoreDistance && elementRect.bottom - headerRect.bottom > topBottomIgnoreDistance)
                    numberOfHeadersToCount++;
            }
            var averageDistanceBetweenHeaders = elementRect.height / numberOfHeadersToCount;
            if (averageDistanceBetweenHeaders < MinimumAverageDistanceBetweenHeaderElements)
                return true;
        }
        return false;
    },
    shouldDisqualifyDueToSimilarElements: function shouldDisqualifyDueToSimilarElements(candidateElements) {
        var baseElement = this.element;
        var candidateClass = baseElement.getAttribute("class");
        if (!candidateClass) {
            baseElement = baseElement.parentElement;
            if (baseElement) {
                candidateClass = baseElement.getAttribute("class");
                if (!candidateClass) {
                    baseElement = baseElement.parentElement;
                    if (baseElement)
                        candidateClass = baseElement.getAttribute("class");
                }
            }
        }
        if (candidateClass) {
            if (candidateElements === undefined)
                candidateElements = [];
            for (var i = 0; i < candidateElements.length; i++)
                candidateElements[i].element.candidateElement = candidateElements[i];
            var elementsOfSameClass;
            try {
                var classNames = candidateClass.split(" ");
                var classQuery = "";
                for (var j = 0; j < classNames.length; j++) {
                    if (classNames[j].length)
                        classQuery += "." + classNames[j];
                }
                elementsOfSameClass = this.contentDocument.querySelectorAll(classQuery);
            } catch (exception) {
                elementsOfSameClass = [];
            }
            var skippedPossiblePrependCandidate = false;
            var baseElementDepth = elementDepth(baseElement);
            for (var i = 0; i < elementsOfSameClass.length; i++) {
                var element = elementsOfSameClass[i];
                if (element == baseElement)
                    continue;
                if (element.parentElement == baseElement || baseElement.parentElement == element)
                    continue;
                if (!isElementVisible(element))
                    continue;
                var candidate = element.candidateElement;
                if (!candidate) {
                    candidate = CandidateElement.candidateIfElementIsViable(element, this.contentDocument, true);
                    if (!candidate)
                        continue;
                }
                if (candidate.basicScore() * ReaderMinimumAdvantage > this.basicScore()) {
                    if (!skippedPossiblePrependCandidate && cachedElementBoundingRect(element).bottom < cachedElementBoundingRect(this.element).top) {
                        skippedPossiblePrependCandidate = true;
                        continue;
                    }
                    if (element.previousElementSibling != null && baseElement.previousElementSibling != null && element.previousElementSibling.className == baseElement.previousElementSibling.className)
                        return true;
                    if (element.nextElementSibling != null && baseElement.nextElementSibling != null && element.nextElementSibling.className == baseElement.nextElementSibling.className)
                        return true;
                    if (elementDepth(element) == baseElementDepth) {
                        while (element.parentElement != null && baseElement.parentElement != null) {
                            if (element.parentElement == baseElement.parentElement)
                                break;
                            element = element.parentElement;
                            baseElement = baseElement.parentElement;
                        }
                    }
                    while (baseElement.childElementCount <= 1) {
                        if (!baseElement.childElementCount || !element.childElementCount)
                            return false;
                        if (element.childElementCount > 1)
                            return false;
                        if (baseElement.firstElementChild.tagName !== element.firstElementChild.tagName)
                            return false;
                        baseElement = baseElement.firstElementChild;
                        element = element.firstElementChild;
                    }
                    if (element.childElementCount <= 1)
                        return false;
                    var elementHeader = element.firstElementChild;
                    var elementFooter = element.lastElementChild;
                    var baseElementHeader = baseElement.firstElementChild;
                    var baseElementFooter = baseElement.lastElementChild;
                    if (elementHeader.tagName !== baseElementHeader.tagName)
                        return false;
                    if (elementFooter.tagName !== baseElementFooter.tagName)
                        return false;
                    var headerClass = elementHeader.className;
                    var footerClass = elementFooter.className;
                    var baseHeaderClass = baseElementHeader.className;
                    var baseFooterClass = elementFooter.className;
                    var acceptableNumberOfElementsWithClassName = (baseFooterClass == baseHeaderClass) ? 2 : 1;
                    if (headerClass.length || baseHeaderClass.length) {
                        if (!headerClass.length || !baseHeaderClass.length)
                            return false;
                        if (headerClass == baseHeaderClass) {
                            if (baseElement.querySelectorAll("." + baseHeaderClass.replace(/\s+/, ".")).length <= acceptableNumberOfElementsWithClassName)
                                return true;
                        }
                    }
                    if (footerClass.length || baseFooterClass.length) {
                        if (!footerClass.length || !baseFooterClass.length)
                            return false;
                        if (footerClass == baseFooterClass && baseElement.querySelectorAll("." + baseFooterClass.replace(/\s+/, ".")).length <= acceptableNumberOfElementsWithClassName)
                            return true;
                    }
                    var baseHeaderHeight = baseElementHeader.clientHeight;
                    var baseFooterHeight = baseElementFooter.clientHeight;
                    if (!baseHeaderHeight || !elementHeader.clientHeight)
                        return false;
                    if (!baseFooterHeight || !elementFooter.clientHeight)
                        return false;
                    if (baseHeaderHeight == elementHeader.clientHeight || baseFooterHeight == elementFooter.clientHeight)
                        return true;
                    return false;
                }
            }
            for (var i = 0; i < candidateElements.length; i++)
                candidateElements[i].element.candidateElement = null;
        }
        return false;
    }
}
String.prototype.lastInteger = function lastInteger() {
    const DecimalRunsRegEx = /[0-9]+/g;
    var decimalRuns = this.match(DecimalRunsRegEx);
    if (decimalRuns)
        return parseInt(decimalRuns[decimalRuns.length - 1]);
    return NaN;
}
String.prototype.trim = function trim() {
    return this.replace(/^\s+/, '').replace(/\s+$/, '');
}
String.prototype.escapeCharacters = function (chars) {
    var foundChar = false;
    for (var i = 0; i < chars.length; ++i) {
        if (this.indexOf(chars.charAt(i)) !== -1) {
            foundChar = true;
            break;
        }
    }
    if (!foundChar)
        return this;
    var result = "";
    for (var i = 0; i < this.length; ++i) {
        if (chars.indexOf(this.charAt(i)) !== -1)
            result += "\\";
        result += this.charAt(i);
    }
    return result;
}
String.prototype.escapeForRegExp = function () {
    return this.escapeCharacters("^[]{}()\\.$*+?|");
}
ReaderArticleFinder = function (contentDocument) {
    this.contentDocument = contentDocument;
    this.didSearchForArticleNode = false;
    this.article = null;
    this.didSearchForExtraArticleNode = false;
    this.extraArticle = null;
    this.leadingImage = null;
    this._cachedScrollY = 0;
    this._cachedScrollX = 0;
    this._elementsWithCachedBoundingRects = [];
    this._cachedContentTextStyle = null;
    this.pageNumber = 1;
    this.prefixWithDateForNextPageURL = null;
}
ReaderArticleFinder.prototype = {
    isReaderModeAvailable: function isReaderModeAvailable() {
        this.cacheWindowScrollPosition();
        var article = this.articleNode();
        return article != null;
    },
    prepareToTransitionToReader: function prepareToTransitionToReader() {
        clearCachedElementBoundingRects();
        this.cacheWindowScrollPosition();
        this.adoptableArticle(true);
        this.nextPageURL();
        this.articleIsLTR();
    },
    nextPageURL: function nextPageURL() {
        if (this._nextPageURL === undefined) {
            var nextPageURLString = this.nextPageURLString();
            if (nextPageURLString) {
                nextPageURLString = ReaderArticleFinderJSController.substituteURLForNextPageURL(nextPageURLString);
            }
            this._nextPageURL = nextPageURLString;
        }
        return this._nextPageURL;
    },
    classNameIsSignificantInRouteComputation: function classNameIsSignificantInRouteComputation(className) {
        if (!className)
            return false;
        return !(className.toLowerCase() in StylisticClassNames);
    },
    shouldIgnoreInRouteComputation: function shouldIgnoreInRouteComputation(element) {
        if (element.tagName === "SCRIPT" || element.tagName === "LINK" || element.tagName === "STYLE")
            return true;
        if (element.tagName !== "TR")
            return false;
        if (element.offsetHeight)
            return false;
        return true;
    },
    routeToArticleNode: function routeToArticleNode() {
        var hint = [];
        var currentElement = this.articleNode();
        while (currentElement) {
            var step = {};
            step.tagName = currentElement.tagName;
            if (currentElement.id)
                step.id = currentElement.id;
            if (this.classNameIsSignificantInRouteComputation(currentElement.className))
                step.className = currentElement.className;
            step.index = 1;
            for (var sibling = currentElement.previousElementSibling; sibling; sibling = sibling.previousElementSibling) {
                if (!this.shouldIgnoreInRouteComputation(sibling))
                    step.index++;
            }
            hint.unshift(step);
            currentElement = currentElement.parentElement;
        }
        return hint;
    },
    articleNode: function articleNode(forceFindingArticle) {
        if (!this.didSearchForArticleNode || forceFindingArticle) {
            this.article = this.findArticle(forceFindingArticle);
            this.didSearchForArticleNode = true;
            if (this.article)
                this.articleIsLTR();
        }
        return this.article ? this.article.element : null;
    },
    extraArticleNode: function extraArticleNode() {
        if (!this.didSearchForArticleNode)
            this.articleNode();
        if (!this.didSearchForExtraArticleNode) {
            this.extraArticle = this.findExtraArticle();
            this.didSearchForExtraArticleNode = true;
        }
        return this.extraArticle ? this.extraArticle.element : null;
    },
    cacheWindowScrollPosition: function cacheWindowScrollPosition() {
        this._cachedScrollY = window.scrollY;
        this._cachedScrollX = window.scrollX;
    },
    contentTextStyle: function contentTextStyle() {
        if (this._cachedContentTextStyle)
            return this._cachedContentTextStyle;
        this._cachedContentTextStyle = contentTextStyleForNode(this.contentDocument, this.articleNode(), false);
        if (!this._cachedContentTextStyle)
            this._cachedContentTextStyle = getComputedStyle(this.articleNode());
        return this._cachedContentTextStyle;
    },
    commaCountIsLessThan: function commaCountIsLessThan(node, limit) {
        var count = 0;
        var textContent = node.textContent;
        var i = -1;
        while (count < limit && (i = textContent.indexOf(',', i + 1)) >= 0)
            count++;
        return count < limit;
    },
    calculateLinkDensity: function calculateLinkDensity(element) {
        var textLength = removeWhitespace(element.textContent).length;
        if (!textLength)
            return 0;
        var links = element.querySelectorAll("a");
        var linkCharacterCount = 0;
        for (var i = 0; i < links.length; i++)
            linkCharacterCount += removeWhitespace(links[i].textContent).length;
        return linkCharacterCount / textLength;
    },
    shouldPruneElement: function shouldPruneElement(element, originalElement) {
        const MaxInputToParagraphRatio = 0.33;
        const MaxPositiveWeightLinkDensity = 0.5;
        const MaxStandardLinkDensity = 0.2;
        const MinimumTextLength = 25;
        const MinimumAverageImageArea = 200 * 200;
        if (!element.parentElement)
            return false;
        if (element.tagName !== "OBJECT" && element.tagName !== "EMBED" && element.tagName !== "CANVAS") {
            var hasElementOrTextNodeChild = false;
            for (var i = 0; i < element.childNodes.length; i++) {
                var node = element.childNodes[i];
                var nodeType = node.nodeType;
                if (nodeType === Node.ELEMENT_NODE || (nodeType === Node.TEXT_NODE && !isNodeWhitespace(node))) {
                    hasElementOrTextNodeChild = true;
                    break;
                }
            }
            if (!hasElementOrTextNodeChild)
                return true;
        }
        if (element.tagName === "CANVAS")
            return element.parentNode.tagName === "CUFON";
        var classIdWeight = 0;
        if (originalElement) {
            if (PositiveRegEx.test(originalElement.className))
                classIdWeight++;
            if (PositiveRegEx.test(originalElement.id))
                classIdWeight++;
            if (NegativeRegEx.test(originalElement.className))
                classIdWeight--;
            if (NegativeRegEx.test(originalElement.id))
                classIdWeight--;
        }
        if (classIdWeight < 0)
            return true;
        if (element.tagName === "UL") {
            if (originalElement.querySelector("iframe") && originalElement.querySelector("script"))
                return true;
            return false;
        }
        if (element.tagName === "OBJECT") {
            const PlugInsToKeepRegEx = /youtube|vimeo|dailymotion/;
            var embedElement = element.querySelector("embed[src]");
            if (embedElement && PlugInsToKeepRegEx.test(embedElement.src))
                return false;
            var dataAttribute = element.getAttribute("data");
            if (dataAttribute && PlugInsToKeepRegEx.test(dataAttribute))
                return false;
            return true;
        }
        if (element.childElementCount === 1) {
            var childElement = element.firstElementChild;
            if (childElement.tagName === "A")
                return false;
            if (childElement.tagName === "SPAN" && childElement.className === "converted-anchor" && elementHasAncestorWithTagName(childElement, "TABLE"))
                return false;
        }
        var imageElements = element.querySelectorAll("img");
        var imageElementCount = imageElements.length;
        if (imageElementCount) {
            var averageImageArea = 0;
            for (var i = 0; i < imageElementCount; i++) {
                var originalImage = imageElements[i].originalElement;
                if (!isElementVisible(originalImage))
                    continue;
                var originalRect = cachedElementBoundingRect(originalImage);
                averageImageArea += (originalRect.width / imageElementCount) * (originalRect.height / imageElementCount);
            }
            if (averageImageArea > MinimumAverageImageArea)
                return false;
        }
        if (!this.commaCountIsLessThan(element, 10))
            return false;
        var p = element.querySelectorAll("p").length;
        var br = element.querySelectorAll("br").length;
        var numParagraphs = p + Math.floor(br / 2);
        if (imageElementCount > numParagraphs)
            return true;
        if (element.querySelectorAll("li").length > numParagraphs)
            return true;
        if (element.querySelectorAll("input").length / numParagraphs > MaxInputToParagraphRatio)
            return true;
        if (element.textContent.length < MinimumTextLength && (imageElementCount != 1))
            return true;
        if (element.querySelector("embed"))
            return true;
        var linkDensity = this.calculateLinkDensity(element);
        if (classIdWeight >= 1 && linkDensity > MaxPositiveWeightLinkDensity)
            return true;
        if (classIdWeight < 1 && linkDensity > MaxStandardLinkDensity)
            return true;
        if (element.tagName === "TABLE") {
            var textLength = removeWhitespace(element.innerText).length;
            var originalTextLength = removeWhitespace(originalElement.innerText).length;
            if (textLength <= (originalTextLength * 0.5))
                return true;
        }
        return false;
    },
    wordCountIsLessThan: function wordCountIsLessThan(node, limit) {
        var count = 0;
        var textContent = node.textContent;
        var i = -1;
        while ((i = textContent.indexOf(' ', i + 1)) >= 0 && count < limit)
            count++;
        return count < limit;
    },
    leadingImageIsAppropriateWidth: function leadingImageIsAppropriateWidth(image) {
        if (!this.article || !image)
            return false;
        return image.getBoundingClientRect().width >= this.article.element.getBoundingClientRect().width;
    },
    newDivFromNode: function newDivFromNode(node) {
        var div = this.contentDocument.createElement("div");
        if (node)
            div.innerHTML = node.innerHTML;
        return div;
    },
    adoptableLeadingImage: function adoptableLeadingImage() {
        const LeadingImageMaximumContainerChildren = 5;
        const LeadingImageMinimumAbsoluteWidth = 600;
        const LeadingImageCreditRegex = /credit/;
        const LeadingImageCaptionRegex = /caption/;
        const LeadingImageAttributeToKeepRegex = /src|alt/;
        if (!this.article || !this.leadingImage || !this.leadingImageIsAppropriateWidth(this.leadingImage))
            return null;
        var leadingImageContainer = this.leadingImage.parentNode;
        var originalCredit = null;
        var originalCaption = null;
        var numChildren = leadingImageContainer.children.length;
        if (leadingImageContainer.tagName === "DIV" && numChildren > 1 && numChildren < LeadingImageMaximumContainerChildren) {
            var texts = leadingImageContainer.cloneNode(true).querySelectorAll("p, div");
            for (var i = 0, length = texts.length; i < length; i++) {
                var text = texts[i];
                if (LeadingImageCreditRegex.test(text.className))
                    originalCredit = text.cloneNode(true);
                else if (LeadingImageCaptionRegex.test(text.className))
                    originalCaption = text.cloneNode(true);
            }
        }
        var image = this.leadingImage.cloneNode(false);
        var attributes = image.attributes;
        for (var i = 0; i < attributes.length; i++) {
            var attributeName = attributes[i].nodeName;
            if (!LeadingImageAttributeToKeepRegex.test(attributeName)) {
                image.removeAttribute(attributeName);
                i--;
            }
        }
        image.className = image.width >= LeadingImageMinimumAbsoluteWidth ? "full-width" : null;
        var container = this.contentDocument.createElement("div");
        container.className = "leading-image";
        container.appendChild(image);
        if (originalCredit) {
            var credit = this.newDivFromNode(originalCredit);
            credit.className = "credit";
            container.appendChild(credit);
        }
        if (originalCaption) {
            var caption = this.newDivFromNode(originalCaption);
            caption.className = "caption";
            container.appendChild(caption);
        }
        return container;
    },
    adoptableArticle: function adoptableArticle(forceFindingArticle) {
        if (this._adoptableArticle !== undefined) {
            return this._adoptableArticle.cloneNode(true);
        }
        var rootElement = this.articleNode(forceFindingArticle);
        this._adoptableArticle = rootElement ? rootElement.cloneNode(true) : null;
        if (!this._adoptableArticle)
            return this._adoptableArticle;
        this._adoptableArticle = this.cleanArticleNode(rootElement, this._adoptableArticle, false)
        var extraArticle = this.extraArticleNode();
        if (extraArticle) {
            var cleanedExtraNode = this.cleanArticleNode(extraArticle, extraArticle.cloneNode(true), true);
            if (cleanedExtraNode) {
                if (this.extraArticle.isPrepended)
                    this._adoptableArticle.insertBefore(cleanedExtraNode, this._adoptableArticle.firstChild);
                else
                    this._adoptableArticle.appendChild(cleanedExtraNode);
            }
        }
        this._articleTextContent = this._adoptableArticle.innerText;
        var leadingImage = this.adoptableLeadingImage();
        if (leadingImage)
            this._adoptableArticle.insertBefore(leadingImage, this._adoptableArticle.firstChild);
        return this._adoptableArticle;
    },
    cleanArticleNode: function cleanArticleNode(originalArticleNode, clonedArticleNode, allowedToReturnNull) {
        const tagNamesToAlwaysPrune = {
            "FORM": 1,
            "IFRAME": 1,
            "SCRIPT": 1,
            "STYLE": 1,
            "LINK": 1
        };
        const tagNamesToConsiderPruning = {
            "DIV": 1,
            "TABLE": 1,
            "OBJECT": 1,
            "UL": 1,
            "CANVAS": 1
        };
        const tagNamesAffectingFontStyle = {
            "I": 1,
            "EM": 1
        };
        const tagNamesAffectingFontWeight = {
            "B": 1,
            "STRONG": 1,
            "H1": 1,
            "H2": 1,
            "H3": 1,
            "H4": 1,
            "H5": 1,
            "H6": 1
        };
        const MaximumFloatingContentRatio = 0.8;
        var elementsToConsiderPruning = [];
        var depthInFloat = 0;
        var depthInTable = 0;
        var depthInFontStyle = 0;
        var depthInFontWeight = 0;
        var currentElement = originalArticleNode;
        var view = currentElement.ownerDocument.defaultView;
        var currentCloneElement = clonedArticleNode;
        var articleTitle = this.articleTitle();
        var articleTitleElement = this._articleTitleElement;

        function incrementDepthLevels(delta) {
            if (depthInFloat)
                depthInFloat += delta;
            if (depthInTable)
                depthInTable += delta;
            if (depthInFontStyle)
                depthInFontStyle += delta;
            if (depthInFontWeight)
                depthInFontWeight += delta;
        };

        function updateDepthLevelsAfterSiblingTraversal() {
            if (depthInFloat === 1)
                depthInFloat = 0;
            if (depthInTable === 1)
                depthInTable = 0;
            if (depthInFontStyle === 1)
                depthInFontStyle = 0;
            if (depthInFontWeight === 1)
                depthInFontWeight = 0;
        };
        var articleRect = cachedElementBoundingRect(originalArticleNode);
        var articleArea = articleRect.width * articleRect.height;
        var childFloatArea = 0;
        var articleChildren = originalArticleNode.children;
        for (var i = 0; i < articleChildren.length; i++) {
            var child = articleChildren[i];
            if (getComputedStyle(child).float === "none")
                continue;
            var childRect = cachedElementBoundingRect(child);
            childFloatArea += childRect.width * childRect.height;
        }
        var mostOfDocumentIsFloat = childFloatArea / articleArea > MaximumFloatingContentRatio;
        while (currentElement) {
            var prunedElement = null;
            var tagName = currentCloneElement.tagName;
            currentCloneElement.originalElement = currentElement;
            if (tagName in tagNamesToAlwaysPrune)
                prunedElement = currentCloneElement;
            if (!prunedElement && currentElement === articleTitleElement)
                prunedElement = currentCloneElement;
            if (!prunedElement && (tagName === "H1" || tagName === "H2")) {
                var distanceFromoriginalArticleNodeTop = currentElement.offsetTop - originalArticleNode.offsetTop;
                if (distanceFromoriginalArticleNodeTop < HeaderMinimumDistanceFromArticleTop) {
                    var headerText = innerTextOrTextContent(currentElement);
                    var maxDistanceToConsiderSimilar = headerText.length * HeaderLevenshteinDistanceToLengthRatio;
                    if (levenshteinDistance(articleTitle, headerText) <= maxDistanceToConsiderSimilar)
                        prunedElement = currentCloneElement;
                }
            }
            if (!prunedElement) {
                if (this.isMediaWikiPage() && currentElement.className === "editsection")
                    prunedElement = currentCloneElement;
            }
            var computedStyle;
            if (!prunedElement)
                computedStyle = getComputedStyle(currentElement);
            if (!prunedElement && tagName === "DIV" && currentCloneElement.parentNode) {
                var elements = currentElement.querySelectorAll("a, blockquote, dl, div, img, ol, p, pre, table, ul");
                var inFloat = depthInFloat || computedStyle["float"] !== "none";
                if (!inFloat && !elements.length) {
                    var parentNode = currentCloneElement.parentNode;
                    var replacementNode = this.contentDocument.createElement("p");
                    while (currentCloneElement.firstChild) {
                        var child = currentCloneElement.firstChild;
                        replacementNode.appendChild(child);
                    }
                    parentNode.replaceChild(replacementNode, currentCloneElement);
                    currentCloneElement = replacementNode;
                    currentCloneElement.originalElement = currentElement;
                    tagName = currentCloneElement.tagName;
                }
            }
            if (!prunedElement && currentCloneElement.parentNode && tagName in tagNamesToConsiderPruning)
                elementsToConsiderPruning.push(currentCloneElement);
            if (!prunedElement) {
                if (computedStyle.display === "none" || computedStyle.visibility !== "visible")
                    prunedElement = currentCloneElement;
                else if (currentElement !== originalArticleNode && tagName !== "IMG" && !depthInFloat && computedStyle["float"] !== "none" && !mostOfDocumentIsFloat && (cachedElementBoundingRect(currentElement).height >= FloatMinimumHeight || currentElement.childElementCount > 1))
                    depthInFloat = 1;
            }
            if (!prunedElement) {
                var attributes = currentCloneElement.attributes;
                for (var i = 0; i < attributes.length; i++) {
                    var attributeName = attributes[i].nodeName;
                    if (AttributesToRemoveRegEx.test(attributeName)) {
                        currentCloneElement.removeAttribute(attributeName);
                        i--;
                    }
                }
                if (!depthInFontStyle && computedStyle.fontStyle !== "normal") {
                    if (!(tagName in tagNamesAffectingFontStyle))
                        currentCloneElement.style.fontStyle = computedStyle.fontStyle;
                    depthInFontStyle = 1;
                }
                if (!depthInFontWeight && computedStyle.fontWeight !== "normal") {
                    if (!(tagName in tagNamesAffectingFontWeight))
                        currentCloneElement.style.fontWeight = computedStyle.fontWeight;
                    depthInFontWeight = 1;
                }
                if (depthInFloat) {
                    if (depthInFloat === 1) {
                        if (cachedElementBoundingRect(currentElement).width === cachedElementBoundingRect(originalArticleNode).width)
                            currentCloneElement.setAttribute("class", "float full-width");
                        else
                            currentCloneElement.setAttribute("class", "float " + computedStyle["float"]);
                    }
                    var widthValue = currentElement.style.getPropertyValue("width");
                    if (widthValue)
                        currentCloneElement.style.width = widthValue;
                    else {
                        var rules = view.getMatchedCSSRules(currentElement, "", true);
                        if (rules) {
                            for (var i = rules.length - 1; i >= 0; i--) {
                                widthValue = rules[i].style.getPropertyValue("width");
                                if (widthValue) {
                                    currentCloneElement.style.width = widthValue;
                                    break;
                                }
                            }
                        }
                    }
                    if (depthInFloat === 1 && !widthValue)
                        currentCloneElement.style.width = cachedElementBoundingRect(currentElement).width + "px";
                }
                if (tagName === "TABLE") {
                    if (!depthInTable)
                        depthInTable = 1;
                } else if (tagName === "IMG") {
                    currentCloneElement.removeAttribute("border");
                    currentCloneElement.removeAttribute("hspace");
                    currentCloneElement.removeAttribute("vspace");
                    currentCloneElement.removeAttribute("align");
                    if (!depthInFloat) {
                        var imageBoundingRect = cachedElementBoundingRect(currentElement);
                        if (imageBoundingRect.width < ImageSizeTiny && imageBoundingRect.height < ImageSizeTiny)
                            currentCloneElement.setAttribute("class", "reader-image-tiny");
                        else if ((imageBoundingRect.width / cachedElementBoundingRect(originalArticleNode).width) > ImageWidthToParentWidthRatio) {
                            currentCloneElement.setAttribute("class", "reader-image-large");
                        }
                    } else {
                        currentCloneElement.style.float = computedStyle.float;
                    }
                } else if (tagName === "FONT") {
                    currentCloneElement.removeAttribute("size");
                    currentCloneElement.removeAttribute("face");
                    currentCloneElement.removeAttribute("color");
                } else if (tagName === "A" && currentCloneElement.parentNode) {
                    var href = currentCloneElement.getAttribute("href");
                    if (href && href.length && (href[0] === "#" || href.substring(0, 11) === "javascript:")) {
                        if (!depthInTable && !currentCloneElement.childElementCount && currentCloneElement.parentElement.childElementCount === 1) {
                            var xPathResult = this.contentDocument.evaluate("text()", currentCloneElement.parentElement, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
                            if (!xPathResult.snapshotLength)
                                prunedElement = currentCloneElement;
                        }
                        if (!prunedElement) {
                            var replacementNode = this.contentDocument.createElement("span");
                            if (currentCloneElement.childElementCount === 1 && currentCloneElement.firstElementChild.tagName === "IMG") {
                                var imageElement = currentCloneElement.firstElementChild;
                                if (imageElement.width > AnchorImageMinimumWidth && imageElement.height > AnchorImageMinimumHeight)
                                    replacementNode.setAttribute("class", "converted-image-anchor");
                            }
                            if (!replacementNode.className)
                                replacementNode.setAttribute("class", "converted-anchor");
                            while (currentCloneElement.firstChild)
                                replacementNode.appendChild(currentCloneElement.firstChild);
                            currentCloneElement.parentNode.replaceChild(replacementNode, currentCloneElement);
                            currentCloneElement = replacementNode;
                        }
                    }
                }
            }
            var firstElementChild = prunedElement ? null : currentElement.firstElementChild;
            if (firstElementChild) {
                currentElement = firstElementChild;
                currentCloneElement = currentCloneElement.firstElementChild;
                incrementDepthLevels(1);
            } else {
                var nextElementSibling;
                while (currentElement !== originalArticleNode && !(nextElementSibling = currentElement.nextElementSibling)) {
                    currentElement = currentElement.parentElement;
                    currentCloneElement = currentCloneElement.parentElement;
                    incrementDepthLevels(-1);
                }
                if (currentElement === originalArticleNode) {
                    if (prunedElement) {
                        if (prunedElement.parentElement)
                            prunedElement.parentElement.removeChild(prunedElement);
                        else if (allowedToReturnNull)
                            return null;
                    }
                    break;
                }
                currentElement = nextElementSibling;
                currentCloneElement = currentCloneElement.nextElementSibling;
                updateDepthLevelsAfterSiblingTraversal();
            }
            if (prunedElement) {
                if (prunedElement.parentElement)
                    prunedElement.parentElement.removeChild(prunedElement);
                else if (allowedToReturnNull)
                    return null;
            }
        }
        for (var i = elementsToConsiderPruning.length - 1; i >= 0; i--) {
            var element = elementsToConsiderPruning[i];
            if (element.parentNode && this.shouldPruneElement(element, element.originalElement))
                element.parentNode.removeChild(element);
        }
        var floatElements = this._adoptableArticle.querySelectorAll(".float");
        for (var i = 0; i < floatElements.length; i++) {
            var pruneFloatedElement = false;
            var floatElement = floatElements[i];
            if (!pruneFloatedElement) {
                var anchors = floatElement.querySelectorAll("a, span.converted-image-anchor");
                var replacedAnchors = floatElement.querySelectorAll("span.converted-anchor");
                pruneFloatedElement = floatElement.parentNode && replacedAnchors.length > anchors.length;
            }
            if (!pruneFloatedElement) {
                var plugInsInClonedElement = floatElement.querySelectorAll("embed, object").length;
                var plugInsInOriginalElement = floatElement.originalElement.querySelectorAll("embed, object").length;
                if (!plugInsInClonedElement && plugInsInOriginalElement)
                    pruneFloatedElement = true;
            }
            if (!pruneFloatedElement) {
                var imagesInOriginalElement = floatElement.originalElement.querySelectorAll("img");
                var visibleImagesInOriginalElementCount = 0;
                for (var j = 0; j < imagesInOriginalElement.length; j++) {
                    if (isElementVisible(imagesInOriginalElement[j]))
                        visibleImagesInOriginalElementCount++;
                    if (visibleImagesInOriginalElementCount > 1)
                        break;
                }
                if (visibleImagesInOriginalElementCount === 1) {
                    var imagesInClonedElementCount = floatElement.querySelectorAll("img").length;
                    if (!imagesInClonedElementCount)
                        pruneFloatedElement = true;
                }
            }
            if (pruneFloatedElement)
                floatElement.parentNode.removeChild(floatElement);
        }
        if (allowedToReturnNull && !removeWhitespace(clonedArticleNode.innerText).length)
            return null;
        return clonedArticleNode;
    },
    leadingImageNode: function leadingImageNode() {
        const LeadingImageMinimumHeight = 250;
        const LeadingImageMinimumWidthRatio = 0.5;
        const LeadingImageNumberOfAncestorsToSearch = 3;
        var searchScope = this.article.element;
        for (var ancestorCount = 0; ancestorCount < LeadingImageNumberOfAncestorsToSearch; ancestorCount++) {
            if (!searchScope.parentNode)
                break;
            searchScope = searchScope.parentNode;
            var image = searchScope.getElementsByTagName("img")[0];
            if (image) {
                var imageRect = cachedElementBoundingRect(image);
                if (imageRect.height >= LeadingImageMinimumHeight && imageRect.width >= this._articleWidth * LeadingImageMinimumWidthRatio) {
                    var position = this.article.element.compareDocumentPosition(image);
                    if (!(position & DocumentPositionPreceding) || (position & DocumentPositionContainedBy))
                        continue;
                    position = this.extraArticle ? this.extraArticle.element.compareDocumentPosition(image) : null;
                    if (position && (!(position & DocumentPositionPreceding) || (position & DocumentPositionContainedBy)))
                        continue;
                    return image;
                }
            }
        }
        return null;
    },
    articleTitle: function articleTitle() {
        if (this._articleTitle !== undefined)
            return this._articleTitle;
        const HeaderMaximumDistance = 500;
        const HeaderMinimumTextLength = 8;
        const HeaderMinimumFontSize = 12;
        const HeaderFontSizeBonusMinimumRatio = 1.1;
        const HeaderFontSizeBonusMultiplier = 1.25;
        const HeaderBonusRegEx = /header|title|headline/i;
        const HeaderRegexBonusMultiplier = 1.5;
        const HeaderContentBonusMultiplier = 1.5;
        const HeaderMaximumDOMDistance = 9;
        const HeaderMinimumFontSizeDifference = 1.5;

        function isPrefixOrSuffix(headerText, documentTitle) {
            var position = headerText ? documentTitle.indexOf(headerText) : -1;
            return (position != -1 && (position == 0 || position + headerText.length == documentTitle.length));
        }
        var articleRect = cachedElementBoundingRect(this.articleNode());
        if (this.extraArticleNode() && this.extraArticle.isPrepended)
            articleRect = cachedElementBoundingRect(this.extraArticleNode());
        var articleCenterX = articleRect.left + (articleRect.width / 2);
        var articleTopY = articleRect.top;
        var articleAdjustedTopY = articleTopY;
        this._articleWidth = articleRect.width;
        this.leadingImage = this.leadingImageNode();
        if (this.leadingImage) {
            var imageRect = cachedElementBoundingRect(this.leadingImage);
            articleAdjustedTopY = imageRect.top;
        }
        var allHeaders = this.contentDocument.querySelectorAll("h1, h2, h3, h4, h5, .headline, .article_title, #hn-headline, .inside-head");
        var bestHeader;
        for (var i = 0; i < allHeaders.length; i++) {
            var header = allHeaders[i];
            var headerRect = cachedElementBoundingRect(header);
            var headerCenterX = headerRect.left + (headerRect.width / 2);
            var headerCenterY = headerRect.top + (headerRect.height / 2);
            var deltaX = headerCenterX - articleCenterX;
            var deltaY = headerCenterY - articleAdjustedTopY;
            var distance = Math.sqrt((deltaX * deltaX) + (deltaY * deltaY));
            var headerScore = Math.max(HeaderMaximumDistance - distance, 0);
            if (distance > HeaderMaximumDistance)
                continue;
            if (headerCenterX < articleRect.left || headerCenterX > articleRect.right)
                continue;
            var headerFontSize = fontSizeFromComputedStyle(getComputedStyle(header));
            if (headerFontSize < HeaderMinimumFontSize)
                continue;
            var headerText = header.innerText;
            if (isPrefixOrSuffix(headerText, this.contentDocument.title))
                headerScore *= HeaderContentBonusMultiplier;
            else if (headerText.length < HeaderMinimumTextLength)
                continue;
            headerScore *= 1 + TitleCandidateDepthScoreMultiplier * elementDepth(header);
            headerScore *= (headerFontSize / BaseFontSize);
            var fontSize = parseInt(this.contentTextStyle().fontSize);
            if (parseInt(headerFontSize) > fontSize * HeaderFontSizeBonusMinimumRatio)
                headerScore *= HeaderFontSizeBonusMultiplier;
            if (HeaderBonusRegEx.test(header.className) || HeaderBonusRegEx.test(header.id))
                headerScore *= HeaderRegexBonusMultiplier;
            if (!bestHeader || headerScore > bestHeader.headerScore) {
                bestHeader = header;
                bestHeader.headerScore = headerScore;
                bestHeader.headerText = headerText;
            }
        }
        if (bestHeader && domDistance(bestHeader, this.articleNode(), HeaderMaximumDOMDistance + 1) > HeaderMaximumDOMDistance) {
            if (parseInt(getComputedStyle(bestHeader).fontSize) < HeaderMinimumFontSizeDifference * fontSize)
                bestHeader = null;
        }
        if (bestHeader) {
            this._articleTitle = bestHeader.headerText.trim();
            this._articleTitleElement = bestHeader;
        }
        if (!this._articleTitle)
            this._articleTitle = this.contentDocument.title;
        return this._articleTitle;
    },
    articleIsLTR: function articleIsLTR() {
        if (this._articleIsLTR === undefined) {
            var computedStyle = getComputedStyle(this.articleNode());
            this._articleIsLTR = computedStyle ? computedStyle.direction === "ltr" : true;
        }
        return this._articleIsLTR;
    },
    findSuggestedCandidate: function findSuggestedCandidate() {
        var route = this.suggestedRouteToArticle;
        if (!route || !route.length)
            return null;
        var node;
        var i;
        for (i = route.length - 1; i >= 0; i--) {
            if (route[i].id) {
                node = this.contentDocument.getElementById(route[i].id);
                if (node)
                    break;
            }
        }
        i++;
        if (!node)
            node = this.contentDocument;
        while (i < route.length) {
            var step = route[i];
            var child = node.nodeType === Node.DOCUMENT_NODE ? node.documentElement : node.firstElementChild;
            for (var j = 1; child && j < step.index; child = child.nextElementSibling) {
                if (!this.shouldIgnoreInRouteComputation(child))
                    j++;
            }
            if (!child)
                return null;
            if (child.tagName !== step.tagName)
                return null;
            if (step.className && child.className !== step.className)
                return null;
            node = child;
            i++;
        }
        if (!isElementVisible(node))
            return null;
        return new CandidateElement(node, this.contentDocument);
    },
    findArticleTagCandidateElement: function findArticleTagCandidateElement() {
        var articleTagElements = this.contentDocument.querySelectorAll("article");
        if (articleTagElements.length != 1)
            return null;
        return CandidateElement.candidateIfElementIsViable(articleTagElements[0], this.contentDocument);
    },
    canRunReaderDetection: function () {
        var hostname = this.contentDocument.location.hostname;
        var pathname = this.contentDocument.location.pathname;
        for (var hostString in BlacklistedHostsAllowedPathPrefixesMap) {
            var hostRegex = new RegExp(hostString.escapeForRegExp());
            if (!hostRegex.test(hostname))
                continue;
            var allowedPathPrefixes = BlacklistedHostsAllowedPathPrefixesMap[hostString];
            for (var i = 0; i < allowedPathPrefixes.length; ++i) {
                var pathPrefix = allowedPathPrefixes[i];
                if (pathname.substring(0, pathPrefix.length) === pathPrefix)
                    return true;
            }
            return false;
        }
        return true;
    },
    findArticle: function findArticle(forceFindingArticle) {
        if (!this.canRunReaderDetection())
            return null;
        var suggestedCandidate = this.findSuggestedCandidate();
        var candidateElements = this.findCandidateElements();
        if (!candidateElements || !candidateElements.length)
            return suggestedCandidate;
        if (suggestedCandidate && suggestedCandidate.basicScore() >= ReaderMinimumScore)
            return suggestedCandidate;
        var articleTagElement = this.findArticleTagCandidateElement()
        if (articleTagElement)
            return articleTagElement;
        var highestScoringElement = this.highestScoringCandidateFromCandidates(candidateElements);
        if (highestScoringElement.element.tagName === "BLOCKQUOTE") {
            var blockquoteParent = highestScoringElement.element.parentNode;
            var numberOfCandidateElements = candidateElements.length;
            for (var i = 0; i < numberOfCandidateElements; i++) {
                var candidateElement = candidateElements[i];
                if (candidateElement.element === blockquoteParent) {
                    highestScoringElement = candidateElement;
                    break;
                }
            }
        }
        if (suggestedCandidate && highestScoringElement.finalScore() < ReaderMinimumScore)
            return suggestedCandidate;
        if (highestScoringElement.shouldDisqualifyDueToScoreDensity()) {
            var elements = highestScoringElement.element.querySelectorAll("ul", "li");
            for (var i = 0; i < elements.length; i++) {
                var prohibitedListElementChildren = elements[i].querySelectorAll("a", "div", "h1", "h2", "h3", "h4", "h5", "h6", "hr", "table");
                if (prohibitedListElementChildren.length > 0)
                    continue;
                var textNodes = highestScoringElement.usableTextNodesInElement(elements[i]);
                if (!textNodes.length)
                    continue;
                for (var j = 0; j < textNodes.length; j++)
                    highestScoringElement.textNodes.push(textNodes[j]);
            }
            highestScoringElement.rawScore = highestScoringElement.calculateRawScore();
            if (!forceFindingArticle && highestScoringElement.shouldDisqualifyDueToScoreDensity())
                return null;
        }
        if (!forceFindingArticle) {
            if (highestScoringElement.shouldDisqualifyDueToHorizontalRuleDensity())
                return null;
            if (highestScoringElement.shouldDisqualifyDueToHeaderDensity())
                return null;
            if (highestScoringElement.shouldDisqualifyDueToSimilarElements(candidateElements))
                return null;
        }
        return highestScoringElement;
    },
    findExtraArticle: function findExtraArticle() {
        if (!this.article)
            return null;
        for (var i = 0, candidateSearchScope = this.article.element; i < 3 && candidateSearchScope; i++, candidateSearchScope = candidateSearchScope.parentNode) {
            var candidateElements = this.findExtraArticleCandidateElements(candidateSearchScope);
            if (!candidateElements || !candidateElements.length)
                continue;
            var sortedCandidateElements = this.sortCandidateElementsInDescendingScoreOrder(candidateElements);
            var highestScoringCandidate;
            for (var candidateIndex = 0; candidateIndex < sortedCandidateElements.length; candidateIndex++) {
                highestScoringCandidate = sortedCandidateElements[candidateIndex];
                if (!highestScoringCandidate || !highestScoringCandidate.basicScore())
                    break;
                if (highestScoringCandidate.shouldDisqualifyDueToScoreDensity())
                    continue;
                if (highestScoringCandidate.shouldDisqualifyDueToHorizontalRuleDensity())
                    continue;
                if (highestScoringCandidate.shouldDisqualifyDueToHeaderDensity())
                    continue;
                if (cachedElementBoundingRect(highestScoringCandidate.element).height < PrependedArticleCandidateMinimumHeight && cachedElementBoundingRect(this.article.element).width != cachedElementBoundingRect(highestScoringCandidate.element).width)
                    continue;
                var textNodeStyle = contentTextStyleForNode(this.contentDocument, highestScoringCandidate.element, true);
                if (!textNodeStyle)
                    continue;
                if (textNodeStyle.fontFamily !== this.contentTextStyle().fontFamily || textNodeStyle.fontSize !== this.contentTextStyle().fontSize)
                    continue;
                if (highestScoringCandidate)
                    return highestScoringCandidate;
            }
        }
        return null;
    },
    highestScoringCandidateFromCandidates: function highestScoringCandidateFromCandidates(candidateElements) {
        var highestScore = 0;
        var highestScoringElement = null;
        for (var i = 0; i < candidateElements.length; i++) {
            var candidateElement = candidateElements[i];
            var score = candidateElement.basicScore();
            if (score >= highestScore) {
                highestScore = score;
                highestScoringElement = candidateElement;
            }
        }
        return highestScoringElement;
    },
    sortCandidateElementsInDescendingScoreOrder: function sortCandidateElementsInDescendingScoreOrder(candidateElements) {
        function sortByScore(candidate1, candidate2) {
            if (candidate1.basicScore() != candidate2.basicScore())
                return candidate2.basicScore() - candidate1.basicScore();
            return candidate2.depth() - candidate1.depth();
        }
        return candidateElements.sort(sortByScore);
    },
    findCandidateElements: function findCandidateElements() {
        const MaximumCandidateDetectionTimeInterval = 1000;
        var findCandidateElementsTimeoutDate = Date.now() + MaximumCandidateDetectionTimeInterval;
        var elements = this.contentDocument.getElementsByTagName("*");
        var candidateElements = [];
        for (var i = 0; i < elements.length; i++) {
            var element = elements[i];
            if (shouldIgnoreElementBySelfOrAncestorTagName(element))
                continue;
            var candidate = CandidateElement.candidateIfElementIsViable(element, this.contentDocument);
            if (candidate)
                candidateElements.push(candidate);
            if (Date.now() > findCandidateElementsTimeoutDate) {
                console.assert(false, "ReaderArticleFinder aborting CandidateElement detection due to timeout");
                candidateElements = [];
                break;
            }
        }
        for (var i = 0; i < candidateElements.length; i++)
            candidateElements[i].element.candidateElement = candidateElements[i];
        for (var i = 0; i < candidateElements.length; i++) {
            var candidateElement = candidateElements[i];
            if (candidateElement.element.tagName !== "BLOCKQUOTE")
                continue;
            var parentCandidateElement = candidateElement.element.parentElement.candidateElement;
            if (!parentCandidateElement)
                continue;
            parentCandidateElement.addTextNodesFromCandidateElement(candidateElement);
        }
        for (var i = 0; i < candidateElements.length; i++)
            candidateElements[i].element.candidateElement = null;
        return candidateElements;
    },
    findExtraArticleCandidateElements: function findExtraArticleCandidateElements(searchScope) {
        if (!this.article)
            return [];
        if (!searchScope)
            searchScope = this.article.element;
        var xPathQuery = "preceding-sibling::*/descendant-or-self::*";
        var xPathResults = this.contentDocument.evaluate(xPathQuery, searchScope, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
        var possibleCandidateCount = xPathResults.snapshotLength;
        var candidateElements = [];
        for (var i = 0; i < possibleCandidateCount; i++) {
            var element = xPathResults.snapshotItem(i);
            if (shouldIgnoreElementBySelfOrAncestorTagName(element))
                continue;
            var candidate = CandidateElement.extraArticleCandidateIfElementIsViable(element, this.article, this.contentDocument, true);
            if (candidate)
                candidateElements.push(candidate);
        }
        xPathQuery = "following-sibling::*/descendant-or-self::*";
        xPathResults = this.contentDocument.evaluate(xPathQuery, searchScope, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
        possibleCandidateCount = xPathResults.snapshotLength;
        for (var i = 0; i < possibleCandidateCount; i++) {
            var element = xPathResults.snapshotItem(i);
            if (shouldIgnoreElementBySelfOrAncestorTagName(element))
                continue;
            var candidate = CandidateElement.extraArticleCandidateIfElementIsViable(element, this.article, this.contentDocument, false);
            if (candidate)
                candidateElements.push(candidate);
        }
        return candidateElements;
    },
    isGeneratedBy: function isGeneratedBy(pattern) {
        var generatorMeta = this.contentDocument.head ? this.contentDocument.head.querySelector("meta[name=generator]") : null;
        if (!generatorMeta)
            return false;
        var generator = generatorMeta.content;
        if (!generator)
            return false;
        return pattern.test(generator);
    },
    isMediaWikiPage: function isMediaWikiPage() {
        return this.isGeneratedBy(/^MediaWiki /);
    },
    isWordPressSite: function isWordPressSite() {
        return this.isGeneratedBy(/^WordPress/);
    },
    nextPageURLString: function nextPageURLString() {
        if (!this.article)
            return null;
        if (this.isMediaWikiPage())
            return null;
        var bestLink;
        var bestLinkScore = 0;
        var searchScope = this.article.element;
        if (searchScope.parentNode && getComputedStyle(searchScope).display === "inline")
            searchScope = searchScope.parentNode;
        var possibleSearchScope = searchScope;
        var minimumBottomOffset = cachedElementBoundingRect(searchScope).bottom + LinkMaxVerticalDistanceFromArticle;
        while (isElementNode(possibleSearchScope) && cachedElementBoundingRect(possibleSearchScope).bottom <= minimumBottomOffset)
            possibleSearchScope = possibleSearchScope.parentNode;
        if (possibleSearchScope !== searchScope && (possibleSearchScope === this.contentDocument || isElementNode(possibleSearchScope)))
            searchScope = possibleSearchScope;
        var anchorElements = this.contentDocument.evaluate(LinkCandidateXPathQuery, searchScope, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
        var numberOfLinks = anchorElements.snapshotLength;
        if (this.pageNumber <= 2 && !this.prefixWithDateForNextPageURL) {
            var articleURL = this.contentDocument.location.pathname;
            var dateMatch = articleURL.match(LinkDateRegex);
            if (dateMatch) {
                dateMatch = dateMatch[0];
                this.prefixWithDateForNextPageURL = articleURL.substring(0, articleURL.indexOf(dateMatch) + dateMatch.length);
            }
        }
        for (var i = 0; i < numberOfLinks; i++) {
            var link = anchorElements.snapshotItem(i);
            var score = this.scoreNextPageLinkCandidate(link);
            if (score > bestLinkScore) {
                bestLink = link;
                bestLinkScore = score;
            }
        }
        return bestLink ? bestLink.href : null;
    },
    scoreNextPageLinkCandidate: function scoreNextPageLinkCandidate(link) {
        function isNextOrdinal(referenceString, linkString, linkText, pageNumber) {
            if (linkString.substring(0, referenceString.length) === referenceString) {
                linkString = linkString.substring(referenceString.length);
                referenceString = "";
            }
            var linkOrdinal = linkString.lastInteger();
            if (isNaN(linkOrdinal))
                return false;
            var referenceOrdinal = referenceString ? referenceString.lastInteger() : NaN;
            if (isNaN(referenceOrdinal) || referenceOrdinal >= MaximumExactIntegralValue)
                referenceOrdinal = pageNumber;
            if (linkOrdinal == referenceOrdinal)
                return linkText.lastInteger() === referenceOrdinal + 1;
            return linkOrdinal === referenceOrdinal + 1;
        }

        function parametersFromSearch(search) {
            var map = {};
            var parameters = search.substring(1).split("&");
            for (var i = 0; i < parameters.length; i++) {
                var parameter = parameters[i];
                var equalsIndex = parameter.indexOf("=");
                if (equalsIndex === -1)
                    map[parameter] = null;
                else
                    map[parameter.substring(0, equalsIndex)] = parameter.substring(equalsIndex + 1);
            }
            return map;
        }
        var referenceLocation = this.contentDocument.location;
        if (link.host !== referenceLocation.host)
            return 0;
        if (link.pathname === referenceLocation.pathname && link.search === referenceLocation.search)
            return 0;
        if (link.toString().indexOf("#") != -1)
            return 0;
        if (!isElementVisible(link))
            return 0;
        var linkBoundingRect = cachedElementBoundingRect(link);
        var articleBoundingRect = cachedElementBoundingRect(this.article.element);
        var verticalDistanceFromArticle = Math.max(0, Math.max(articleBoundingRect.top - (linkBoundingRect.top + linkBoundingRect.height), linkBoundingRect.top - (articleBoundingRect.top + articleBoundingRect.height)));
        if (linkBoundingRect.top < articleBoundingRect.top)
            return 0;
        if (verticalDistanceFromArticle > LinkMaxVerticalDistanceFromArticle)
            return 0;
        var horizontalDistanceFromArticle = Math.max(0, Math.max(articleBoundingRect.left - (linkBoundingRect.left + linkBoundingRect.width), linkBoundingRect.left - (articleBoundingRect.left + articleBoundingRect.width)));
        if (horizontalDistanceFromArticle > 0)
            return 0;
        var referenceLocationPath = referenceLocation.pathname;
        var linkPath = link.pathname;
        if (this.prefixWithDateForNextPageURL) {
            if (link.pathname.indexOf(this.prefixWithDateForNextPageURL) == -1)
                return 0;
            referenceLocationPath = referenceLocationPath.substring(this.prefixWithDateForNextPageURL.length);
            linkPath = linkPath.substring(this.prefixWithDateForNextPageURL.length);
        }
        var linkPathComponents = linkPath.substring(1).split("/");
        if (!linkPathComponents[linkPathComponents.length - 1])
            linkPathComponents.pop();
        var referencePathComponents = referenceLocationPath.substring(1).split("/");
        var linkEndsWithSlash = false;
        if (!referencePathComponents[referencePathComponents.length - 1]) {
            linkEndsWithSlash = true;
            referencePathComponents.pop();
        }
        if (linkPathComponents.length < referencePathComponents.length)
            return 0;
        var mismatchCount = 0;
        var nextOrdinalMatchValue = 0;
        var linkText = link.textContent;
        for (var i = 0; i < linkPathComponents.length; i++) {
            var linkComponent = linkPathComponents[i];
            var referenceComponent = i < referencePathComponents.length ? referencePathComponents[i] : "";
            if (referenceComponent !== linkComponent) {
                if (i < referencePathComponents.length - 2)
                    return 0;
                if (linkComponent.length >= referenceComponent.length) {
                    var commonSuffixLength = 0;
                    while (linkComponent[linkComponent.length - 1 - commonSuffixLength] === referenceComponent[referenceComponent.length - 1 - commonSuffixLength])
                        commonSuffixLength++;
                    if (commonSuffixLength) {
                        linkComponent = linkComponent.substring(0, linkComponent.length - commonSuffixLength);
                        referenceComponent = referenceComponent.substring(0, referenceComponent.length - commonSuffixLength);
                    }
                }
                if (isNextOrdinal(referenceComponent, linkComponent, linkText, this.pageNumber))
                    nextOrdinalMatchValue = Math.pow(LinkNextOrdinalValueBase, (i - linkPathComponents.length + 1));
                else
                    mismatchCount++;
            }
            if (mismatchCount > 1)
                return 0;
        }
        var didEarnURLSemanticBonus = false;
        if (link.search) {
            linkParameters = parametersFromSearch(link.search);
            referenceParameters = parametersFromSearch(referenceLocation.search);
            for (var key in linkParameters) {
                var linkValue = linkParameters[key];
                var referenceValue = key in referenceParameters ? referenceParameters[key] : null;
                if (referenceValue !== linkValue) {
                    if (referenceValue === null)
                        referenceValue = "";
                    if (linkValue === null)
                        linkValue = "";
                    if (linkValue.length < referenceValue.length)
                        mismatchCount++;
                    else if (isNextOrdinal(referenceValue, linkValue, linkText, this.pageNumber)) {
                        if (LinkURLSearchParameterKeyMatchRegex.test(key)) {
                            if (referenceLocationPath.toLowerCase() === linkPath.toLowerCase()) {
                                if (this.isWordPressSite() && linkEndsWithSlash)
                                    return 0;
                                didEarnURLSemanticBonus = true;
                            } else
                                return 0;
                        } else if (LinkURLBadSearchParameterKeyMatchRegex.test(key)) {
                            mismatchCount++;
                            continue;
                        }
                        nextOrdinalMatchValue = Math.max(nextOrdinalMatchValue, 1 / LinkNextOrdinalValueBase);
                    } else
                        mismatchCount++;
                }
            }
        }
        if (!nextOrdinalMatchValue)
            return 0;
        if (LinkURLPageSlashNumberMatchRegex.test(link.href) || LinkURLSlashDigitEndMatchRegex.test(link.href))
            didEarnURLSemanticBonus = true;
        if (!didEarnURLSemanticBonus && linkPathComponents.length == referencePathComponents.length && stringSimilarity(referenceLocationPath, linkPath) < LinkMinimumURLSimilarityRatio)
            return 0;
        if (LinkURLArchiveSlashDigitEndMatchRegex.test(link))
            return 0;
        var score = LinkMatchWeight * (Math.pow(LinkMismatchValueBase, -mismatchCount) + nextOrdinalMatchValue) + LinkVerticalDistanceFromArticleWeight * verticalDistanceFromArticle / LinkMaxVerticalDistanceFromArticle;
        if (didEarnURLSemanticBonus)
            score += LinkURLSemanticMatchBonus;
        if (link.parentNode.tagName === "LI")
            score += LinkListItemBonus;
        var linkText = link.innerText;
        if (LinkNextMatchRegEx.test(linkText))
            score += LinkNextMatchBonus;
        if (LinkPageMatchRegEx.test(linkText))
            score += LinkPageMatchBonus;
        if (LinkContinueMatchRegEx.test(linkText))
            score += LinkContinueMatchBonus;
        return score;
    },
    articleTextContent: function articleTextContent() {
        return this._articleTextContent;
    },
    readingListItemInformation: function readingListItemInformation() {
        const ReaderTitleMaxLength = 140;
        const ReaderPreviewTextMaxLength = 140;
        var title;
        var previewText;
        var isReaderAvailable = false;
        if (this.adoptableArticle()) {
            title = this.articleTitle();
            previewText = this.articleTextContent();
            isReaderAvailable = true;
        } else {
            title = this.contentDocument.title;
            previewText = this.contentDocument.body.innerText;
        }
        if (!title)
            title = this.contentDocument.location.href;
        title = title.trim().substring(0, ReaderTitleMaxLength);
        if (!previewText)
            previewText = "";
        previewText = previewText.trim().substring(0, ReaderPreviewTextMaxLength).replace(/[\s]+/g, ' ');
        var info = {
            "title": title,
            "previewText": previewText,
            "isReaderAvailable": isReaderAvailable
        };
        return info;
    }
}
var ReaderArticleFinderJS = new ReaderArticleFinder(document);