/// <summary>
/// Collapses internal whitespace to single space, removes leading/trailing whitespace, folds case.
/// </summary>
private static string NormalizeReference(StringPart s)
{
if (s.Length == 0)
return string.Empty;
return NormalizeWhitespace(s.Source, s.StartIndex, s.Length).ToUpperInvariant();
}
/// <summary>
/// Adds a new reference to the dictionary, if the label does not already exist there.
/// Assumes that the length of the label does not exceed <see cref="Reference.MaximumReferenceLabelLength"/>.
/// </summary>
private static void AddReference(Dictionary<string, Reference> refmap, StringPart label, string url, string title)
{
var normalizedLabel = NormalizeReference(label);
if (refmap.ContainsKey(normalizedLabel))
return;
refmap.Add(normalizedLabel, new Reference(normalizedLabel, url, title));
}
/// <summary>
/// Checks if the reference dictionary contains a reference with the given label and returns it,
/// otherwise returns <c>null</c>.
/// Returns <see cref="Reference.InvalidReference"/> if the reference label is not valid.
/// </summary>
private static Reference LookupReference(Dictionary<string, Reference> refmap, StringPart lab)
{
if (refmap == null)
return null;
if (lab.Length > Reference.MaximumReferenceLabelLength)
return Reference.InvalidReference;
string label = NormalizeReference(lab);
Reference r;
if (refmap.TryGetValue(label, out r))
return r;
return null;
}
/// <summary>
/// Checks if the reference dictionary contains a reference with the given label and returns it,
/// otherwise returns <see langword="null"/>.
/// Returns <see cref="Reference.InvalidReference"/> if the reference label is not valid.
/// </summary>
private static Reference LookupReference(DocumentData data, StringPart lab)
{
if (data?.ReferenceMap == null)
return null;
if (lab.Length > Reference.MaximumReferenceLabelLength)
return Reference.InvalidReference;
string label = NormalizeReference(lab);
Reference r;
if (data.ReferenceMap.TryGetValue(label, out r))
return r;
return null;
}
public void Write(StringPart value)
{
if (value.Length == 0)
return;
if (this.Buffer.Length < value.Length)
this.Buffer = new char[value.Length];
value.Source.CopyTo(value.StartIndex, this.Buffer, 0, value.Length);
if (this._windowsNewLine)
{
var lastPos = value.StartIndex;
var pos = lastPos;
while (-1 != (pos = value.Source.IndexOf('\n', pos, value.Length - pos + value.StartIndex)))
{
var lastC = pos == 0 ? this._last : value.Source[pos - 1];
if (lastC != '\r')
{
this._inner.Write(this.Buffer, lastPos - value.StartIndex, pos - lastPos);
this._inner.Write('\r');
lastPos = pos;
}
pos++;
}
this._inner.Write(this.Buffer, lastPos - value.StartIndex, value.Length - lastPos + value.StartIndex);
}
else
{
this._inner.Write(this.Buffer, 0, value.Length);
}
this._last = this.Buffer[value.Length - 1];
}
private void WriteEncodedHtml(StringPart text)
{
HtmlFormatterSlim.EscapeHtml(text, _target);
}
private void Write(StringPart text)
{
_target.Write(text);
}
private static Inline HandleRightSquareBracket(Subject subj, CommonMarkSettings settings)
{
// move past ']'
subj.Position++;
bool canClose;
var istack = InlineStack.FindMatchingOpener(subj.LastPendingInline, InlineStack.InlineStackPriority.Links, '[', out canClose);
if (istack != null)
{
// if the opener is "inactive" then it means that there was a nested link
if (istack.DelimeterCount == -1)
{
InlineStack.RemoveStackEntry(istack, subj, istack, settings.InlineParserParameters);
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, settings);
// 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.ReferenceMap, label, settings);
}
if (details == Reference.InvalidReference)
details = null;
MatchSquareBracketStack(istack, subj, details, settings.InlineParserParameters);
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.Delimeter = '[';
////istack.StartingInline = inlText;
////istack.StartPosition = subj.Position;
////istack.Priority = InlineStack.InlineStackPriority.Links;
////istack.Flags = InlineStack.InlineStackFlags.Closer;
////InlineStack.AppendStackEntry(istack, subj);
}
return inlText;
}
/// <summary>
/// Parses the contents of [..] for a reference label. Only used for parsing
/// reference definition labels for use with the reference dictionary because
/// it does not properly parse nested inlines.
///
/// Assumes the source starts with '[' character or spaces before '['.
/// Returns null and does not advance if no matching ] is found.
/// Note the precedence: code backticks have precedence over label bracket
/// markers, which have precedence over *, _, and other inline formatting
/// markers. So, 2 below contains a link while 1 does not:
/// 1. [a link `with a ](/url)` character
/// 2. [a link *with emphasized ](/url) text* /// </summary>
private static StringPart? ParseReferenceLabel(Subject subj)
{
var startPos = subj.Position;
var source = subj.Buffer;
var len = subj.Length;
while (subj.Position < len)
{
var c = subj.Buffer[subj.Position];
if (c == ' ' || c == '\n')
{
subj.Position++;
continue;
}
else if (c == '[')
{
subj.Position++;
break;
}
else
{
subj.Position = startPos;
return null;
}
}
var labelStartPos = subj.Position;
len = subj.Position + Reference.MaximumReferenceLabelLength;
if (len > source.Length)
len = source.Length;
subj.Position = source.IndexOfAny(BracketSpecialCharacters, subj.Position, len - subj.Position);
while (subj.Position > -1)
{
var c = source[subj.Position];
if (c == '\\')
{
subj.Position += 2;
if (subj.Position >= len)
break;
subj.Position = source.IndexOfAny(BracketSpecialCharacters, subj.Position, len - subj.Position);
}
else if (c == '[')
{
break;
}
else
{
var label = new StringPart(source, labelStartPos, subj.Position - labelStartPos);
subj.Position++;
return label;
}
}
subj.Position = startPos;
return null;
}
/// <summary>
/// Collapses internal whitespace to single space, removes leading/trailing whitespace, folds case.
/// </summary>
private static string NormalizeReference(StringPart s, CommonMarkSettings settings)
{
if (s.Length == 0)
return string.Empty;
var result = NormalizeWhitespace(s.Source, s.StartIndex, s.Length);
if (0 == (settings.AdditionalFeatures & CommonMarkAdditionalFeatures.RespectReferenceCase))
result = result.ToUpperInvariant();
return result;
}
/// <summary>
/// Escapes special HTML characters.
/// </summary>
/// <remarks>Orig: escape_html(inp, preserve_entities)</remarks>
internal static void EscapeHtml(StringPart input, HtmlTextWriter target)
{
if (input.Length == 0)
return;
int pos;
int lastPos = input.StartIndex;
char[] buffer;
if (target.Buffer.Length < input.Length)
buffer = target.Buffer = new char[input.Length];
else
buffer = target.Buffer;
input.Source.CopyTo(input.StartIndex, buffer, 0, input.Length);
while ((pos = input.Source.IndexOfAny(EscapeHtmlCharacters, lastPos, input.Length - lastPos + input.StartIndex)) != -1)
{
target.Write(buffer, lastPos - input.StartIndex, pos - lastPos);
lastPos = pos + 1;
switch (input.Source[pos])
{
case '<':
target.WriteConstant(EscapeHtmlLessThan);
break;
case '>':
target.WriteConstant(EscapeHtmlGreaterThan);
break;
case '&':
target.WriteConstant(EscapeHtmlAmpersand);
break;
case '"':
target.WriteConstant(EscapeHtmlQuote);
break;
}
}
target.Write(buffer, lastPos - input.StartIndex, input.Length - lastPos + input.StartIndex);
}