private static Inline HandleLeftSquareBracket(Subject subj, bool isImage)
{
Inline inlText;
if (isImage)
{
inlText = new Inline("![", subj.Position - 1, subj.Position + 1);
}
else
{
inlText = new Inline("[", subj.Position, subj.Position + 1);
}
// move past the '['
subj.Position++;
var istack = new InlineStack();
istack.Delimiter = '[';
istack.StartingInline = inlText;
istack.StartPosition = subj.Position;
istack.Priority = InlineStack.InlineStackPriority.Links;
istack.Flags = InlineStack.InlineStackFlags.Opener | (isImage ? InlineStack.InlineStackFlags.ImageLink : InlineStack.InlineStackFlags.None);
InlineStack.AppendStackEntry(istack, subj);
return(inlText);
}
public static Inline parse_inlines(Subject subj, Func <Subject, Inline>[] parsers, char[] specialCharacters)
{
var len = subj.Length;
if (len == 0)
{
return(null);
}
var first = ParseInline(subj, parsers, specialCharacters);
subj.LastInline = first.LastSibling;
Inline cur;
while (subj.Position < len)
{
cur = ParseInline(subj, parsers, specialCharacters);
if (cur != null)
{
subj.LastInline.NextSibling = cur;
subj.LastInline = cur.LastSibling;
}
}
InlineStack.PostProcessInlineStack(subj, subj.FirstPendingInline, subj.LastPendingInline, InlineStack.InlineStackPriority.Maximum);
return(first);
}
private static Inline HandleOpenerCloser(Subject subj, InlineTag singleCharTag, InlineTag doubleCharTag)
{
bool canOpen, canClose;
var c = subj.Buffer[subj.Position];
var numdelims = ScanEmphasisDelimiters(subj, c, out canOpen, out canClose);
if (canClose)
{
// walk the stack and find a matching opener, if there is one
var istack = InlineStack.FindMatchingOpener(subj.LastPendingInline, InlineStack.InlineStackPriority.Emphasis, c, numdelims, canOpen, out canClose);
if (istack != null)
{
var useDelims = MatchInlineStack(istack, subj, numdelims, null, singleCharTag, doubleCharTag);
if (useDelims > 0)
{
// if the closer was not fully used, move back a char or two and try again.
if (useDelims < numdelims)
{
subj.Position = subj.Position - numdelims + useDelims;
// use recursion only if it will not be very deep.
// however it cannot be used if the single char will not be parsed.
if (numdelims < 10)
{
return(HandleOpenerCloser(subj, singleCharTag, doubleCharTag));
}
}
return(null);
}
}
}
var inlText = new Inline(subj.Buffer, subj.Position - numdelims, numdelims, subj.Position - numdelims, subj.Position, c);
if (canOpen || canClose)
{
var istack = new InlineStack();
istack.DelimiterCount = numdelims;
istack.Delimiter = c;
istack.StartingInline = inlText;
istack.Priority = InlineStack.InlineStackPriority.Emphasis;
istack.Flags = (canOpen ? InlineStack.InlineStackFlags.Opener : 0)
| (canClose ? (InlineStack.InlineStackFlags.Closer | InlineStack.InlineStackFlags.CloserOriginally) : 0);
InlineStack.AppendStackEntry(istack, subj);
}
return(inlText);
}
internal static void MatchSquareBracketStack(InlineStack opener, Subject subj, Reference details)
{
if (details != null)
{
var inl = opener.StartingInline;
var isImage = 0 != (opener.Flags & InlineStack.InlineStackFlags.ImageLink);
inl.Tag = isImage ? InlineTag.Image : (details.IsPlaceholder ? InlineTag.Placeholder : InlineTag.Link);
inl.FirstChild = inl.NextSibling;
inl.NextSibling = null;
inl.SourceLastPosition = subj.Position;
inl.TargetUrl = details.Url;
inl.LiteralContent = details.Title;
if (!isImage && !details.IsPlaceholder)
{
// since there cannot be nested links, remove any other link openers before this
var temp = opener.Previous;
while (temp != null && temp.Priority <= InlineStack.InlineStackPriority.Links)
{
if (temp.Delimiter == '[' && temp.Flags == opener.Flags)
{
// mark the previous entries as "inactive"
if (temp.DelimiterCount == -1)
{
break;
}
temp.DelimiterCount = -1;
}
temp = temp.Previous;
}
}
InlineStack.RemoveStackEntry(opener, subj, null);
subj.LastInline = inl;
}
else
{
// this looked like a link, but was not.
// remove the opener stack entry but leave the inbetween intact
InlineStack.RemoveStackEntry(opener, subj, opener);
var inl = new Inline("]", subj.Position - 1, subj.Position);
subj.LastInline.LastSibling.NextSibling = inl;
subj.LastInline = inl;
}
}
public static void AppendStackEntry(InlineStack entry, Subject subj)
{
if (subj.LastPendingInline != null)
{
entry.Previous = subj.LastPendingInline;
subj.LastPendingInline.Next = entry;
}
if (subj.FirstPendingInline == null)
{
subj.FirstPendingInline = entry;
}
subj.LastPendingInline = entry;
}
public static InlineStack FindMatchingOpener(InlineStack searchBackwardsFrom, InlineStackPriority priority,
char delimiter, int closerDelimiterCount, bool closerCanOpen, out bool canClose)
{
canClose = true;
var istack = searchBackwardsFrom;
while (true)
{
if (istack == null)
{
// this cannot be a closer since there is no opener available.
canClose = false;
return(null);
}
if (istack.Priority > priority ||
(istack.Delimiter == delimiter && 0 != (istack.Flags & InlineStackFlags.Closer)))
{
// there might be a closer further back but we cannot go there yet because a higher priority element is blocking
// the other option is that the stack entry could be a closer for the same char - this means
// that any opener we might find would first have to be matched against this closer.
return(null);
}
if (istack.Delimiter == delimiter)
{
// interior closer of size 2 does not match opener of size 1 and vice versa.
// for more details, see https://github.com/jgm/cmark/commit/c50197bab81d7105c9c790548821b61bcb97a62a
var oddMatch = (closerCanOpen || (istack.Flags & InlineStackFlags.CloserOriginally) > 0) &&
istack.DelimiterCount != closerDelimiterCount &&
((istack.DelimiterCount + closerDelimiterCount) % 3 == 0);
if (!oddMatch)
{
return(istack);
}
}
istack = istack.Previous;
}
}
private static Inline HandleRightSquareBracket(Subject subj, bool supportPlaceholderBrackets)
{
// move past ']'
subj.Position++;
bool canClose;
var istack = InlineStack.FindMatchingOpener(subj.LastPendingInline, InlineStack.InlineStackPriority.Links, '[', 1, false, out canClose);
if (istack != null)
{
// if the opener is "inactive" then it means that there was a nested link
if (istack.DelimiterCount == -1)
{
InlineStack.RemoveStackEntry(istack, subj, istack);
return(new Inline("]", subj.Position - 1, subj.Position));
}
var endpos = subj.Position;
// try parsing details for '[foo](/url "title")' or '[foo][bar]'
//var details = ParseLinkDetails(subj);
var details = ParseLinkDetails(subj, supportPlaceholderBrackets);
// try lookup of the brackets themselves
if (details == null || details == Reference.SelfReference)
{
var startpos = istack.StartPosition;
var label = new StringPart(subj.Buffer, startpos, endpos - startpos - 1);
details = LookupReference(subj.DocumentData, label);
}
if (details == Reference.InvalidReference)
{
details = null;
}
MatchSquareBracketStack(istack, subj, details);
return(null);
}
var inlText = new Inline("]", subj.Position - 1, subj.Position);
if (canClose)
{
// note that the current implementation will not work if there are other inlines with priority
// higher than Links.
// to fix this the parsed link details should be added to the closer element in the stack.
throw new NotSupportedException("It is not supported to have inline stack priority higher than Links.");
////istack = new InlineStack();
////istack.Delimiter = '[';
////istack.StartingInline = inlText;
////istack.StartPosition = subj.Position;
////istack.Priority = InlineStack.InlineStackPriority.Links;
////istack.Flags = InlineStack.InlineStackFlags.Closer;
////InlineStack.AppendStackEntry(istack, subj);
}
return(inlText);
}
internal static int MatchInlineStack(InlineStack opener, Subject subj, int closingDelimiterCount, InlineStack closer, InlineTag singleCharTag, InlineTag doubleCharTag)
{
// calculate the actual number of delimiters used from this closer
int useDelims;
var openerDelims = opener.DelimiterCount;
if (closingDelimiterCount < 3 || openerDelims < 3)
{
useDelims = closingDelimiterCount <= openerDelims ? closingDelimiterCount : openerDelims;
if (useDelims == 1 && singleCharTag == 0)
{
return(0);
}
}
else if (singleCharTag == 0)
{
useDelims = 2;
}
else if (doubleCharTag == 0)
{
useDelims = 1;
}
else
{
useDelims = closingDelimiterCount % 2 == 0 ? 2 : 1;
}
Inline inl = opener.StartingInline;
InlineTag tag = useDelims == 1 ? singleCharTag : doubleCharTag;
if (openerDelims == useDelims)
{
// the opener is completely used up - remove the stack entry and reuse the inline element
inl.Tag = tag;
inl.LiteralContent = null;
inl.FirstChild = inl.NextSibling;
inl.NextSibling = null;
InlineStack.RemoveStackEntry(opener, subj, closer?.Previous);
}
else
{
// the opener will only partially be used - stack entry remains (truncated) and a new inline is added.
opener.DelimiterCount -= useDelims;
inl.LiteralContent = inl.LiteralContent.Substring(0, opener.DelimiterCount);
inl.SourceLastPosition -= useDelims;
inl.NextSibling = new Inline(tag, inl.NextSibling);
inl = inl.NextSibling;
inl.SourcePosition = opener.StartingInline.SourcePosition + opener.DelimiterCount;
}
// there are two callers for this method, distinguished by the `closer` argument.
// if closer == null it means the method is called during the initial subject parsing and the closer
// characters are at the current position in the subject. The main benefit is that there is nothing
// parsed that is located after the matched inline element.
// if closer != null it means the method is called when the second pass for previously unmatched
// stack elements is done. The drawback is that there can be other elements after the closer.
if (closer != null)
{
var clInl = closer.StartingInline;
if ((closer.DelimiterCount -= useDelims) > 0)
{
// a new inline element must be created because the old one has to be the one that
// finalizes the children of the emphasis
var newCloserInline = new Inline(clInl.LiteralContent.Substring(useDelims));
newCloserInline.SourcePosition = inl.SourceLastPosition = clInl.SourcePosition + useDelims;
newCloserInline.SourceLength = closer.DelimiterCount;
newCloserInline.NextSibling = clInl.NextSibling;
clInl.LiteralContent = null;
clInl.NextSibling = null;
inl.NextSibling = closer.StartingInline = newCloserInline;
}
else
{
inl.SourceLastPosition = clInl.SourceLastPosition;
clInl.LiteralContent = null;
inl.NextSibling = clInl.NextSibling;
clInl.NextSibling = null;
}
}
else if (subj != null)
{
inl.SourceLastPosition = subj.Position - closingDelimiterCount + useDelims;
subj.LastInline = inl;
}
return(useDelims);
}
public static void PostProcessInlineStack(Subject subj, InlineStack first, InlineStack last, InlineStackPriority ignorePriority)
{
while (ignorePriority > 0)
{
var istack = first;
while (istack != null)
{
if (istack.Priority >= ignorePriority)
{
RemoveStackEntry(istack, subj, istack);
}
else if (0 != (istack.Flags & InlineStackFlags.Closer))
{
bool canClose;
var iopener = FindMatchingOpener(istack.Previous, istack.Priority, istack.Delimiter, istack.DelimiterCount, (istack.Flags & InlineStackFlags.Opener) > 0, out canClose);
if (iopener != null)
{
bool retry = false;
if (iopener.Delimiter == '~')
{
InlineMethods.MatchInlineStack(iopener, subj, istack.DelimiterCount, istack, (InlineTag)0, InlineTag.Strikethrough);
if (istack.DelimiterCount > 1)
{
retry = true;
}
}
else
{
var useDelims = InlineMethods.MatchInlineStack(iopener, subj, istack.DelimiterCount, istack, InlineTag.Emphasis, InlineTag.Strong);
if (istack.DelimiterCount > 0)
{
retry = true;
}
}
if (retry)
{
// remove everything between opened and closer (not inclusive).
if (istack.Previous != null && iopener.Next != istack.Previous)
{
RemoveStackEntry(iopener.Next, subj, istack.Previous);
}
continue;
}
else
{
// remove opener, everything in between, and the closer
RemoveStackEntry(iopener, subj, istack);
}
}
else if (!canClose)
{
// this case means that a matching opener does not exist
// remove the Closer flag so that a future Opener can be matched against it.
istack.Flags &= ~InlineStackFlags.Closer;
}
}
if (istack == last)
{
break;
}
istack = istack.Next;
}
ignorePriority--;
}
}
/// <summary>
/// Removes a subset of the stack.
/// </summary>
/// <param name="first">The first entry to be removed.</param>
/// <param name="subj">The subject associated with this stack. Can be <see langword="null"/> if the pointers in the subject should not be updated.</param>
/// <param name="last">The last entry to be removed. Can be <see langword="null"/> if everything starting from <paramref name="first"/> has to be removed.</param>
public static void RemoveStackEntry(InlineStack first, Subject subj, InlineStack last)
{
var curPriority = first.Priority;
if (last == null)
{
if (first.Previous != null)
{
first.Previous.Next = null;
}
else if (subj != null)
{
subj.FirstPendingInline = null;
}
if (subj != null)
{
last = subj.LastPendingInline;
subj.LastPendingInline = first.Previous;
}
first = first.Next;
}
else
{
if (first.Previous != null)
{
first.Previous.Next = last.Next;
}
else if (subj != null)
{
subj.FirstPendingInline = last.Next;
}
if (last.Next != null)
{
last.Next.Previous = first.Previous;
}
else if (subj != null)
{
subj.LastPendingInline = first.Previous;
}
if (first == last)
{
return;
}
first = first.Next;
last = last.Previous;
}
if (last == null || first == null)
{
return;
}
first.Previous = null;
last.Next = null;
// handle case like [*b*] (the whole [..] is being removed but the inner *..* must still be matched).
// this is not done automatically because the initial * is recognized as a potential closer (assuming
// potential scenario '*[*' ).
if (curPriority > 0)
{
PostProcessInlineStack(null, first, last, curPriority);
}
}