static Common()
{
BoldItalicTextInline.AddTripChars(_triggerList);
BoldTextInline.AddTripChars(_triggerList);
ItalicTextInline.AddTripChars(_triggerList);
MarkdownLinkInline.AddTripChars(_triggerList);
HyperlinkInline.AddTripChars(_triggerList);
CommentInline.AddTripChars(_triggerList);
StrikethroughTextInline.AddTripChars(_triggerList);
SuperscriptTextInline.AddTripChars(_triggerList);
SubscriptTextInline.AddTripChars(_triggerList);
CodeInline.AddTripChars(_triggerList);
ImageInline.AddTripChars(_triggerList);
EmojiInline.AddTripChars(_triggerList);
LinkAnchorInline.AddTripChars(_triggerList);
// Create an array of characters to search against using IndexOfAny.
_tripCharacters = _triggerList.Select(trigger => trigger.FirstChar).Distinct().ToArray();
}
/// <summary>
/// Attempts to parse a comment span.
/// </summary>
/// <param name="markdown"> The markdown text. </param>
/// <param name="start"> The location to start parsing. </param>
/// <param name="maxEnd"> The location to stop parsing. </param>
/// <returns> A parsed bold text span, or <c>null</c> if this is not a bold text span. </returns>
internal static InlineParseResult Parse(string markdown, int start, int maxEnd)
{
if (start >= maxEnd - 1)
{
return(null);
}
// Check the start sequence.
string startSequence = markdown.Substring(start, 2);
if (startSequence != "<a")
{
return(null);
}
// Find the end of the span. The end sequence ('-->')
var innerStart = start + 2;
int innerEnd = Common.IndexOf(markdown, "</a>", innerStart, maxEnd);
int trueEnd = innerEnd + 4;
if (innerEnd == -1)
{
innerEnd = Common.IndexOf(markdown, "/>", innerStart, maxEnd);
trueEnd = innerEnd + 2;
if (innerEnd == -1)
{
return(null);
}
}
// This link Reference wasn't closed properly if the next link starts before a close.
var nextLink = Common.IndexOf(markdown, "<a", innerStart, maxEnd);
if (nextLink > -1 && nextLink < innerEnd)
{
return(null);
}
var length = trueEnd - start;
var contents = markdown.Substring(start, length);
string link = null;
try
{
var xml = XElement.Parse(contents);
var attr = xml.Attribute("name");
if (attr != null)
{
link = attr.Value;
}
}
catch
{
// Attempting to fetch link failed, ignore and continue.
}
// Remove whitespace if it exists.
if (trueEnd + 1 <= maxEnd && markdown[trueEnd] == ' ')
{
trueEnd += 1;
}
// We found something!
var result = new LinkAnchorInline
{
Raw = contents,
Link = link
};
return(new InlineParseResult(result, start, trueEnd));
}
/// <summary>
/// Finds the next inline element by matching trip chars and verifying the match.
/// </summary>
/// <param name="markdown"> The markdown text to parse. </param>
/// <param name="start"> The position to start parsing. </param>
/// <param name="end"> The position to stop parsing. </param>
/// <param name="ignoreLinks"> Indicates whether to parse links. </param>
/// <returns>Returns the next element</returns>
private static InlineParseResult FindNextInlineElement(string markdown, int start, int end, bool ignoreLinks)
{
// Search for the next inline sequence.
for (int pos = start; pos < end; pos++)
{
// IndexOfAny should be the fastest way to skip characters we don't care about.
pos = markdown.IndexOfAny(_tripCharacters, pos, end - pos);
if (pos < 0)
{
break;
}
// Find the trigger(s) that matched.
char currentChar = markdown[pos];
foreach (InlineTripCharHelper currentTripChar in _triggerList)
{
// Check if our current char matches the suffix char.
if (currentChar == currentTripChar.FirstChar)
{
// Don't match if the previous character was a backslash.
if (pos > start && markdown[pos - 1] == '\\')
{
continue;
}
// If we are here we have a possible match. Call into the inline class to verify.
InlineParseResult parseResult = null;
switch (currentTripChar.Method)
{
case InlineParseMethod.BoldItalic:
parseResult = BoldItalicTextInline.Parse(markdown, pos, end);
break;
case InlineParseMethod.Comment:
parseResult = CommentInline.Parse(markdown, pos, end);
break;
case InlineParseMethod.LinkReference:
parseResult = LinkAnchorInline.Parse(markdown, pos, end);
break;
case InlineParseMethod.Bold:
parseResult = BoldTextInline.Parse(markdown, pos, end);
break;
case InlineParseMethod.Italic:
parseResult = ItalicTextInline.Parse(markdown, pos, end);
break;
case InlineParseMethod.MarkdownLink:
if (!ignoreLinks)
{
parseResult = MarkdownLinkInline.Parse(markdown, pos, end);
}
break;
case InlineParseMethod.AngleBracketLink:
if (!ignoreLinks)
{
parseResult = HyperlinkInline.ParseAngleBracketLink(markdown, pos, end);
}
break;
case InlineParseMethod.Url:
if (!ignoreLinks)
{
parseResult = HyperlinkInline.ParseUrl(markdown, pos, end);
}
break;
case InlineParseMethod.RedditLink:
if (!ignoreLinks)
{
parseResult = HyperlinkInline.ParseRedditLink(markdown, pos, end);
}
break;
case InlineParseMethod.PartialLink:
if (!ignoreLinks)
{
parseResult = HyperlinkInline.ParsePartialLink(markdown, pos, end);
}
break;
case InlineParseMethod.Email:
if (!ignoreLinks)
{
parseResult = HyperlinkInline.ParseEmailAddress(markdown, start, pos, end);
}
break;
case InlineParseMethod.Strikethrough:
parseResult = StrikethroughTextInline.Parse(markdown, pos, end);
break;
case InlineParseMethod.Superscript:
parseResult = SuperscriptTextInline.Parse(markdown, pos, end);
break;
case InlineParseMethod.Subscript:
parseResult = SubscriptTextInline.Parse(markdown, pos, end);
break;
case InlineParseMethod.Code:
parseResult = CodeInline.Parse(markdown, pos, end);
break;
case InlineParseMethod.Image:
parseResult = ImageInline.Parse(markdown, pos, end);
break;
case InlineParseMethod.Emoji:
parseResult = EmojiInline.Parse(markdown, pos, end);
break;
}
if (parseResult != null)
{
return(parseResult);
}
}
}
}
// If we didn't find any elements we have a normal text block.
// Let us consume the entire range.
return(new InlineParseResult(TextRunInline.Parse(markdown, start, end), start, end));
}