/// <summary>
/// Strips the special attributes specified at the location of start. Special attributes are a php markdown extension
/// and specified between {}. Attributes are separated with spaces. It recognizes the following attributes:
/// id, which start with a '#'. Only the first one is used
/// css classes, which start with a'.'. All specified are used
/// name=value pairs, which will end up as attributes on the element.
/// </summary>
/// <param name="str">The string we're scanning.</param>
/// <param name="start">The start (current) position.</param>
/// <param name="end">The end position. Is only valid if returned list contains at least one value.</param>
/// <returns>list of special attributes found, or null if none found or error in string format.</returns>
public static List <string> StripSpecialAttributes(string str, int start, out int end)
{
end = start;
var scanner = new StringScanner(str, start);
if (!scanner.DoesMatch('{'))
{
// not a start of a special attribute block
return(null);
}
// first find the end of the block,
scanner.SkipForward(1);
var startOfAttributes = scanner.Position;
// first find the next EOL, as the closing } has to be on this line.
scanner.SkipToEol();
var nextEolPos = scanner.Position;
scanner.Position = startOfAttributes;
scanner.Mark();
if (!scanner.Find('}') || scanner.Position >= nextEolPos)
{
// not enclosed properly.
return(null);
}
var attributesString = scanner.Extract();
if (string.IsNullOrWhiteSpace(attributesString))
{
return(null);
}
// Position is on enclosing '}' (due to the Find('}'), so we have to skip 1 character
end = scanner.Position + 1;
return(attributesString.Split(' ').Where(s => !string.IsNullOrWhiteSpace(s)).ToList());
}
/// <summary>
/// Skips the font awesome specification at the current specified pos. Pos is inside str at the '@'. font awesome
/// directives are @fa-iconname. newPos is positioned to character after iconname if successful match. iconname scanned is specified in iconname.
/// </summary>
/// <param name="str">The string.</param>
/// <param name="currentPos">The current position.</param>
/// <param name="newPos">The new position.</param>
/// <param name="iconName">Name of the icon.</param>
/// <returns>
/// bool if match was found and properly skipped, otherwise false.
/// </returns>
public static bool SkipFontAwesome(string str, int currentPos, out int newPos, out string iconName)
{
newPos = currentPos;
iconName = string.Empty;
if (str[currentPos] != '@')
{
return(false);
}
var scanner = new StringScanner(str, currentPos);
// skip '@'
scanner.SkipForward(1);
if (!scanner.DoesMatch("fa-"))
{
// not a font awesome specification
return(false);
}
scanner.SkipForward(3);
iconName = string.Empty;
if (!scanner.SkipIdentifier(ref iconName))
{
// no icon name specified
return(false);
}
if (string.IsNullOrWhiteSpace(iconName))
{
return(false);
}
// matched a fontawesome specification
newPos = scanner.Position;
return(true);
}
// Parse just the link target
// For reference link definition, this is the bit after "[id]: thisbit"
// For inline link, this is the bit in the parens: [link text](thisbit)
internal static LinkDefinition ParseLinkTarget(StringScanner p, string id, bool ExtraMode)
{
// Skip whitespace
p.SkipWhitespace();
// End of string?
if (p.eol)
return null;
// Create the link definition
var r = new LinkDefinition(id);
// Is the url enclosed in angle brackets
if (p.SkipChar('<'))
{
// Extract the url
p.Mark();
// Find end of the url
while (p.current != '>')
{
if (p.eof)
return null;
p.SkipEscapableChar(ExtraMode);
}
string url = p.Extract();
if (!p.SkipChar('>'))
return null;
// Unescape it
r.url = Utils.UnescapeString(url.Trim(), ExtraMode);
// Skip whitespace
p.SkipWhitespace();
}
else
{
// Find end of the url
p.Mark();
int paren_depth = 1;
while (!p.eol)
{
char ch=p.current;
if (char.IsWhiteSpace(ch))
break;
if (id == null)
{
if (ch == '(')
paren_depth++;
else if (ch == ')')
{
paren_depth--;
if (paren_depth==0)
break;
}
}
p.SkipEscapableChar(ExtraMode);
}
r.url = Utils.UnescapeString(p.Extract().Trim(), ExtraMode);
}
p.SkipLinespace();
// End of inline target
if (p.DoesMatch(')'))
return r;
bool bOnNewLine = p.eol;
int posLineEnd = p.position;
if (p.eol)
{
p.SkipEol();
p.SkipLinespace();
}
// Work out what the title is delimited with
char delim;
switch (p.current)
{
case '\'':
case '\"':
delim = p.current;
break;
case '(':
delim = ')';
break;
default:
if (bOnNewLine)
{
p.position = posLineEnd;
return r;
}
else
return null;
}
// Skip the opening title delimiter
p.SkipForward(1);
// Find the end of the title
p.Mark();
while (true)
{
if (p.eol)
return null;
if (p.current == delim)
{
if (delim != ')')
{
int savepos = p.position;
// Check for embedded quotes in title
// Skip the quote and any trailing whitespace
p.SkipForward(1);
p.SkipLinespace();
// Next we expect either the end of the line for a link definition
// or the close bracket for an inline link
if ((id == null && p.current != ')') ||
(id != null && !p.eol))
{
continue;
}
p.position = savepos;
}
// End of title
break;
}
p.SkipEscapableChar(ExtraMode);
}
// Store the title
r.title = Utils.UnescapeString(p.Extract(), ExtraMode);
// Skip closing quote
p.SkipForward(1);
// Done!
return r;
}
// Parse just the link target
// For reference link definition, this is the bit after "[id]: thisbit"
// For inline link, this is the bit in the parens: [link text](thisbit)
internal static LinkDefinition ParseLinkTarget(StringScanner p, string id, bool ExtraMode)
{
// Skip whitespace
p.SkipWhitespace();
// End of string?
if (p.eol)
{
return(null);
}
// Create the link definition
var r = new LinkDefinition(id);
// Is the url enclosed in angle brackets
if (p.SkipChar('<'))
{
// Extract the url
p.Mark();
// Find end of the url
while (p.current != '>')
{
if (p.eof)
{
return(null);
}
p.SkipEscapableChar(ExtraMode);
}
string url = p.Extract();
if (!p.SkipChar('>'))
{
return(null);
}
// Unescape it
r.url = Utils.UnescapeString(url.Trim(), ExtraMode);
// Skip whitespace
p.SkipWhitespace();
}
else
{
// Find end of the url
p.Mark();
int paren_depth = 1;
while (!p.eol)
{
char ch = p.current;
if (char.IsWhiteSpace(ch))
{
break;
}
if (id == null)
{
if (ch == '(')
{
paren_depth++;
}
else if (ch == ')')
{
paren_depth--;
if (paren_depth == 0)
{
break;
}
}
}
p.SkipEscapableChar(ExtraMode);
}
r.url = Utils.UnescapeString(p.Extract().Trim(), ExtraMode);
}
p.SkipLinespace();
// End of inline target
if (p.DoesMatch(')'))
{
return(r);
}
bool bOnNewLine = p.eol;
int posLineEnd = p.position;
if (p.eol)
{
p.SkipEol();
p.SkipLinespace();
}
// Work out what the title is delimited with
char delim;
switch (p.current)
{
case '\'':
case '\"':
delim = p.current;
break;
case '(':
delim = ')';
break;
default:
if (bOnNewLine)
{
p.position = posLineEnd;
return(r);
}
else
{
return(null);
}
}
// Skip the opening title delimiter
p.SkipForward(1);
// Find the end of the title
p.Mark();
while (true)
{
if (p.eol)
{
return(null);
}
if (p.current == delim)
{
if (delim != ')')
{
int savepos = p.position;
// Check for embedded quotes in title
// Skip the quote and any trailing whitespace
p.SkipForward(1);
p.SkipLinespace();
// Next we expect either the end of the line for a link definition
// or the close bracket for an inline link
if ((id == null && p.current != ')') ||
(id != null && !p.eol))
{
continue;
}
p.position = savepos;
}
// End of title
break;
}
p.SkipEscapableChar(ExtraMode);
}
// Store the title
r.title = Utils.UnescapeString(p.Extract(), ExtraMode);
// Skip closing quote
p.SkipForward(1);
// Done!
return(r);
}