// Internal for unit testing purposes only.
private int GetDefaultTeaserLength(TeaserTruncationMode mode)
{
switch (mode)
{
case TeaserTruncationMode.Length:
return(defaultLengthAbsolute);
case TeaserTruncationMode.Character:
return(defaultLengthCharacters);
case TeaserTruncationMode.Word:
default:
return(defaultLengthWords);
}
}
private string GetModeDescription(TeaserTruncationMode mode)
{
switch (mode)
{
case TeaserTruncationMode.Length:
return("string length");
case TeaserTruncationMode.Character:
return("letters or digits");
case TeaserTruncationMode.Word:
default:
return("words");
}
}
public TeaserResult GenerateTeaser(
TeaserTruncationMode truncationMode,
int truncationLength,
string html,
string cacheKey,
string slug,
string languageCode)
{
var result = new TeaserResult();
result.Content = html;
result.DidTruncate = false;
return(result);
}
// Internal for unit testing purposes only.
private string TruncatePost(TeaserTruncationMode mode, string content, int length, bool isRightToLeftLanguage = false)
{
var truncateFrom = isRightToLeftLanguage ? TruncateFrom.Left : TruncateFrom.Right;
switch (mode)
{
case TeaserTruncationMode.Length:
return(content.Truncate(length, terminator, Truncator.FixedLength, truncateFrom));
case TeaserTruncationMode.Character:
return(content.Truncate(length, terminator, Truncator.FixedNumberOfCharacters, truncateFrom));
case TeaserTruncationMode.Word:
default:
return(content.Truncate(length, terminator, Truncator.FixedNumberOfWords, truncateFrom));
}
}
private int GetContentLength(string html, TeaserTruncationMode mode)
{
if (string.IsNullOrEmpty(html))
{
return(0);
}
switch (mode)
{
case TeaserTruncationMode.Length:
return(html.Length);
case TeaserTruncationMode.Character:
return(html.ToCharArray().Count(char.IsLetterOrDigit));
case TeaserTruncationMode.Word:
default:
return(html.Split((char[])null, StringSplitOptions.RemoveEmptyEntries).Count());
}
}
public TeaserResult GenerateTeaser(
TeaserTruncationMode truncationMode,
int truncationLength,
string html,
string cacheKey,
string slug,
string languageCode)
{
var result = new TeaserResult();
if (string.IsNullOrWhiteSpace(html))
{
result.Content = html;
result.DidTruncate = false;
return(result);
}
// Try to get language metadata for humanizer.
var cultureInfo = CultureInfo.InvariantCulture;
if (!string.IsNullOrEmpty(languageCode))
{
try
{
cultureInfo = new CultureInfo(languageCode);
}
catch (CultureNotFoundException) { }
}
var contentLength = GetContentLength(html, truncationMode);
if (contentLength <= truncationLength)
{
result.Content = html;
result.DidTruncate = false;
return(result);
}
if (_cache != null)
{
var cachedTeaser = _cache.GetTeaser(cacheKey);
if (!string.IsNullOrEmpty(cachedTeaser))
{
result.Content = cachedTeaser;
result.DidTruncate = true;
return(result);
}
}
var isRightToLeftLanguage = cultureInfo.TextInfo.IsRightToLeft;
// Get global teaser settings.
var truncationLengthToUse = truncationLength <= 0 ? GetDefaultTeaserLength(truncationMode) : truncationLength;
// Truncate the raw content first. In general, Humanizer is smart enough to ignore tags, especially if using word truncation.
var text = TruncatePost(truncationMode, html, truncationLengthToUse, isRightToLeftLanguage);
// Don't leave dangling <p> tags.
HtmlNode.ElementsFlags["p"] = HtmlElementFlag.Closed;
var modeDesc = GetModeDescription(truncationMode);
//if we get bad output try increasing the allowed length unti it is valid
while (!IsValidMarkup(text) && truncationLengthToUse <= contentLength)
{
truncationLengthToUse += 1;
if (_log != null)
{
_log.LogWarning($"teaser truncation for post {slug}, produced invalid html, so trying again and increasing the truncation length to {truncationLengthToUse} {modeDesc}. Might be best to make an explicit teaser for this post.");
}
text = TruncatePost(truncationMode, html, truncationLengthToUse, isRightToLeftLanguage);
}
if (!IsValidMarkup(text))
{
if (_log != null)
{
_log.LogError($"failed to create valid teaser for post {slug}, so returning full content");
}
result.Content = html;
result.DidTruncate = false;
return(result);
}
if (_cache != null)
{
_cache.AddToCache(text, cacheKey);
}
var doc = new HtmlDocument();
doc.LoadHtml(text);
result.Content = doc.DocumentNode.InnerHtml;
result.DidTruncate = true;
return(result);
}
