public WikiLink FindLink(string linkTitle)
{
WikiLink BestLink = null;
// Check for amiguity
var matchingLinkTexts = wikiLinks.Where(x => x.LinkText == linkTitle).ToList();
if (matchingLinkTexts.Count() == 1)
{
return(matchingLinkTexts[0]);
}
var matchingPageTitles = wikiLinks.Where(x => x.PageTitle == linkTitle).ToList();
if (matchingPageTitles.Count() == 1)
{
return(matchingPageTitles[0]);
}
// If No matches have been found, check if there are any close matches
foreach (var link in wikiLinks)
{
// Attempt to identify typos. Set to a threshold of 10% error in the typing as defined by the Levenshtein
// distance (number of corrections needed to get the strings to match)
var maxLevenshteinDistance = (int)Math.Ceiling((decimal)linkTitle.Length * 0.10m);
var similarLinkTitleMatch = string.IsNullOrEmpty(link.LinkText) == false?
LevenshteinDistance(link.LinkText, linkTitle) <= maxLevenshteinDistance : false;
var similarPageTitleMatch = string.IsNullOrEmpty(link.PageTitle) == false?
LevenshteinDistance(link.PageTitle, linkTitle) <= maxLevenshteinDistance : false;
// Don't immediately return a similar match, there might be an exact match somwhere else
if (similarLinkTitleMatch || similarPageTitleMatch)
{
BestLink = link;
}
}
return(BestLink);
}
public async Task <List <WikiLink> > GeneratePageLinks(string url)
{
List <WikiLink> wikiLinks = new List <WikiLink>();
var response = await _httpClient.GetAsync(url);
var pageContents = await response.Content.ReadAsStringAsync();
HtmlDocument pageDocument = new HtmlDocument();
pageDocument.LoadHtml(pageContents);
var links = pageDocument.DocumentNode.SelectNodes("//body//a");
foreach (var link in links)
{
var newWikiLink = new WikiLink();
newWikiLink.LinkText = link.InnerText;
newWikiLink.Url = link.GetAttributeValue("href", null);
if (string.IsNullOrEmpty(newWikiLink.Url) == false)
{
switch (newWikiLink.Url[0])
{
case '/':
newWikiLink.Url = $"https://en.wikipedia.org{newWikiLink.Url}";
break;
case '#':
newWikiLink.Url = $"{url}{newWikiLink.Url}";
break;
}
}
newWikiLink.PageTitle = link.GetAttributeValue("title", null);
wikiLinks.Add(newWikiLink);
}
return(wikiLinks);
}
