metro c# webscraper with HtmlAgilityPack

WebViewReaderMode.cs

using HtmlAgilityPack;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text.RegularExpressions;
using Windows.UI;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Media;

namespace ReaderModeTest1.Common
{
    class WebViewReaderMode
    {
        static WebView wv;
        
        public static string GetUrl(DependencyObject obj)
        {
            return (string)obj.GetValue(UrlProperty);
        }

        public static void SetUrl(DependencyObject obj, string value)
        {
            obj.SetValue(UrlProperty, value);
        }

        public static readonly DependencyProperty UrlProperty =
            DependencyProperty.RegisterAttached("Url", typeof(string), typeof(WebViewReaderMode), new PropertyMetadata("", OnUrlChanged));

        private static void OnUrlChanged(DependencyObject sender, DependencyPropertyChangedEventArgs eventArgs)
        {
            wv = sender as WebView;
            scrapeWebContentAsync(eventArgs.NewValue as string);
              
        }

        public static string GetHeader(DependencyObject obj)
        {
            return (string)obj.GetValue(HeaderProperty);
        }

        public static void SetHeader(DependencyObject obj, string value)
        {
            obj.SetValue(HeaderProperty, value);
        }

        public static readonly DependencyProperty HeaderProperty =
            DependencyProperty.RegisterAttached("Header", typeof(string), typeof(WebViewReaderMode), new PropertyMetadata("", OnHeaderChanged));

        private static void OnHeaderChanged(DependencyObject sender, DependencyPropertyChangedEventArgs eventArgs)
        {

        }

        private static async void scrapeWebContentAsync(string url)
        {
            var htmlWeb = new HtmlWeb();

            var doc = await htmlWeb.LoadFromWebAsync(url);
            doc.OptionOutputAsXml = true;
            doc.OptionFixNestedTags = true;
            doc.OptionAutoCloseOnEnd = true;

            var wordsPerNode = new Dictionary<HtmlNode, Double>();
            var topRatio = 1000000.0;
            HtmlNode articleNode = null;

            if (doc.DocumentNode != null)
            {
                doc.DocumentNode.InnerHtml = Regex.Replace(doc.DocumentNode.InnerHtml, @"[\\\n\t\r]+", "");
                foreach (var n in walkDom(doc.DocumentNode).ToList())
                {
                    if (n.NodeType == HtmlNodeType.Comment) n.Remove();
                    if (n.Name == "script") n.Remove();

                }

                var nodes = walkDom(doc.DocumentNode).OfType<HtmlNode>().ToArray();
                foreach (var n in nodes)
                {
                    if (n.Name == "div")
                    {
                        var len = WCforNode(n);
                        if (len > 250 && getElementsofType(n, "p").Count > 3)
                        {
                            var linkCount = getLinkWC(n);
                            if (linkCount == 0) linkCount = 5;
                            var ratio = Convert.ToDouble(linkCount) / len;
                            if (ratio < topRatio)
                            {
                                topRatio = ratio;
                                articleNode = n;
                            }
                            
                        }

                    }
                }

                if (articleNode != null)
                {
                    var titleText = getElementsofType(doc.DocumentNode, "title").FirstOrDefault().InnerText;
                    var headerText = getTitlefromElement(articleNode, true);

                    if (headerText == "") headerText = getTitlefromElement(articleNode.PreviousSibling);
                    if (headerText == "") headerText = getTitlefromElement(articleNode.ParentNode);
                    if (headerText == "") headerText = getTitlefromElement(articleNode.ParentNode.ParentNode);
                    if (headerText == "") headerText = getTitlefromElement(articleNode.ParentNode.ParentNode.ParentNode);

                    SetHeader(wv, headerText);
                    var tr = new StringWriter();
                    var cleandoc = new HtmlDocument();
                    cleandoc.OptionOutputAsXml = true;
                    cleandoc.OptionFixNestedTags = true;
                    cleandoc.OptionAutoCloseOnEnd = true;

                    cleandoc.LoadHtml(articleNode.OuterHtml);

                    cleandoc.Save(tr);
                    var content = tr.ToString().Replace("<?xml version=\"1.0\" encoding=\"utf-8\"?>", "");
                    var forgroundColor = color2Rbga((App.Current.Resources["ApplicationForegroundThemeBrush"] as SolidColorBrush).Color);
                    var backgroundColor = color2Rbga((App.Current.Resources["ApplicationPageBackgroundThemeBrush"] as SolidColorBrush).Color);
                    var fontFamily = (App.Current.Resources["ContentControlThemeFontFamily"] as FontFamily).Source;
                    var fontSize = App.Current.Resources["ControlContentThemeFontSize"] as double?;

                    content = "<style>*{font-family: Calibri, sans-serif;font-size:" + fontSize + "pt;background-color:" + backgroundColor + ";color:" + forgroundColor + ";}</style>" + content;


                    wv.NavigateToString(content);
                }
            }

        }
        private static string color2Rbga(Color col)
        {
            return " rgba(" +col.R+ "," +col.G +"," +col.B +"," +col.A +") ";
        }

        private static IEnumerable<HtmlNode> walkDom(HtmlNode node)
        {
            yield return node;
            foreach (var child in node.ChildNodes)
                foreach (var x in walkDom(child))
                    yield return x;
        }

        private static string getTitlefromElement(HtmlNode node, bool removeEle = false)
        {
            var headerText = "";
            var articleH1 = getElementsofType(node, "h1");
            if (articleH1.Count > 0 && articleH1.FirstOrDefault().InnerText.Length>15)
            {
                headerText = articleH1.FirstOrDefault().InnerText;
                if(removeEle) articleH1.FirstOrDefault().Remove();
            }
            if (headerText == "")
            {
                var articleH2 = getElementsofType(node, "h2");
                if (articleH2.Count > 0 &&  articleH2.FirstOrDefault().InnerText.Length>15)
                {
                    headerText = articleH2.FirstOrDefault().InnerText;
                    if (removeEle) articleH2.FirstOrDefault().Remove();
                }
            }
            if (headerText == "")
            {
                var articleH3 = getElementsofType(node, "h3");
                if (articleH3.Count > 0 && articleH3.FirstOrDefault().InnerText.Length > 15)
                {
                    headerText = articleH3.FirstOrDefault().InnerText;
                    if (removeEle) articleH3.FirstOrDefault().Remove();
                }
            }
            return headerText;
        }

        private static int WCforNode(HtmlNode node)
        {
            return getElementsofType(node, "#text").SelectMany(segment => Regex.Split(segment.InnerText, "\\w")).Count();
        }

        private static double AvgWCforNode(HtmlNode node, string elementType)
        {
            return getElementsofType(node, elementType).Select(segment => Regex.Split(segment.InnerText, "\\w").Count()).Average();
        }

        private static int getLinkWC(HtmlNode node)
        {
        
        var links      = getElementsofType(node, "a" );
        var WClink=0;   
        foreach (var link in links)
	    {
		  WClink+=WCforNode(link);
	    }
        return WClink;
        }

        private static List<HtmlNode> getElementsofType(HtmlNode node, string elementType)
        {
            return (walkDom(node).ToList()).Where(x => x.Name == elementType).ToList();
        }
     
    }

}