private Token CheckItalic(LexerContext ctx)
{
string lookahead = this.PeekChar(Italic.Length);
if (lookahead == Italic)
{
return new Token {
Type = TokenType.Italic, Value = ctx.Peek ? lookahead : this.ConsumeChar(Italic.Length)
}
}
;
lookahead = this.PeekChar(Italic2.Length);
if (lookahead == Italic2)
{
return new Token {
Type = TokenType.Italic, Value = ctx.Peek ? lookahead : this.ConsumeChar(Italic2.Length)
}
}
;
return(null);
}
private Token CheckCodeBlockLang(LexerContext ctx)
{
string lookahead = this.PeekChar();
Token last = this.Output.LastOrDefault();
if (last == null || last.Type != TokenType.CodeBlock || lookahead == null || lookahead == "\n")
{
return(null);
}
lookahead = "";
int q = 1;
string tmp = null;
while ((tmp = this.PeekChar(q)) != lookahead && !tmp.EndsWith("\n"))
{
lookahead = tmp;
q++;
}
if (!ctx.Peek)
{
this.ConsumeChar(q - 1);
}
return(new Token()
{
Type = TokenType.CodeBlockLang, Value = lookahead
});
}
private Token CheckCodeBlock(LexerContext ctx)
{
if (!this.IsValidBlockStart())
{
return(null);
}
string lookahead = this.PeekChar(Codeblock.Length);
if (lookahead != Codeblock)
{
return(null);
}
// Check for more backticks to see if it is a header
string str = this.PeekChar(Codeblock.Length + 1);
if (str.Length == Codeblock.Length + 1 && str.Last() == Codeblock[0])
{
return(null);
}
return(new Token {
Type = TokenType.CodeBlock, Value = ctx.Peek ? lookahead : this.ConsumeChar(Codeblock.Length)
});
}
private Token CheckLabeledListItem(LexerContext ctx)
{
if (!this.IsValidBlockStart())
{
return(null);
}
string lookahead = this.PeekChar(3);
if (lookahead != null && char.IsLetter(lookahead[0]) && (lookahead.EndsWith(". ") || lookahead.EndsWith(") ")))
{
string originalValue = lookahead;
lookahead = "- ";
if (!ctx.Peek)
{
this.ConsumeChar(3);
}
return(new Token {
Type = TokenType.ListItem, Value = lookahead, OriginalValue = originalValue
});
}
return(null);
}
private Token CheckDmlCodeBlock(LexerContext ctx)
{
if (!this.IsValidBlockStart())
{
return(null);
}
string lookahead = this.PeekChar(DmlCodeblock.Length);
if (lookahead != DmlCodeblock)
{
return(null);
}
string str = this.PeekChar(DmlCodeblock.Length + 1);
if (str.Length == DmlCodeblock.Length + 1 && str.Last() == DmlCodeblock[0])
{
return(null);
}
return(new Token {
Type = TokenType.CodeBlock, Value = ctx.Peek ? lookahead : this.ConsumeChar(DmlCodeblock.Length)
});
}
private Token CheckEscapeBlock(LexerContext ctx)
{
string lookahead = this.PeekChar(2);
if (lookahead == EscapeBlock && !this.LastIs(TokenType.Escape))
{
return new Token {
Type = TokenType.EscapeBlock, Value = ctx.Peek ? lookahead : this.ConsumeChar(2)
}
}
;
return(null);
}
private Token CheckColon(LexerContext ctx)
{
string lookahead = this.PeekChar(Colon.Length);
if (lookahead == Colon)
{
return new Token {
Type = TokenType.Colon, Value = ctx.Peek ? lookahead : this.ConsumeChar(Colon.Length)
}
}
;
return(null);
}
private Token CheckReference(LexerContext ctx)
{
string lookahead = this.PeekChar();
if (this.IsValidBlockStart() && lookahead == Reference)
{
return new Token {
Type = TokenType.Reference, Value = ctx.Peek ? lookahead : this.ConsumeChar()
}
}
;
return(null);
}
private Token CheckListItem(LexerContext ctx)
{
string lookahead = this.PeekChar(2);
if (this.IsValidBlockStart() && lookahead.Length == 2 && Lists.Contains(lookahead[0].ToString()) && lookahead[1] == ' ')
{
return new Token {
Type = TokenType.ListItem, Value = ctx.Peek ? lookahead : this.ConsumeChar(2)
}
}
;
return(null);
}
private Token CheckEscape(LexerContext ctx)
{
string lookahead = this.PeekChar();
if (lookahead == Escape)
{
return new Token {
Type = TokenType.Escape, Value = ctx.Peek ? lookahead : this.ConsumeChar()
}
}
;
return(null);
}
private Token CheckTodoListItem(LexerContext ctx)
{
string lookahead = this.PeekChar(4);
if (this.IsValidBlockStart() && (lookahead == "[ ] " || lookahead == "[x] " || lookahead == "[X] "))
{
return new Token {
Type = TokenType.ListItem, Value = ctx.Peek ? lookahead : ConsumeChar(4)
}
}
;
return(null);
}
private Token CheckStrikethrough(LexerContext ctx)
{
string lookahead = this.PeekChar(Strikethrough.Length);
if (lookahead == Strikethrough)
{
return new Token {
Type = TokenType.Strikethrough, Value = ctx.Peek ? lookahead : this.ConsumeChar(Strikethrough.Length)
}
}
;
return(null);
}
private Token CheckUnderlined(LexerContext ctx)
{
string lookahead = this.PeekChar(Underline.Length);
if (lookahead == Underline)
{
return new Token {
Type = TokenType.Underlined, Value = ctx.Peek ? lookahead : this.ConsumeChar(Underline.Length)
}
}
;
return(null);
}
private Token CheckHeader(LexerContext ctx)
{
string lookahead = this.PeekChar(1);
if (!Headers.Contains(lookahead))
{
return(null);
}
if (!this.IsValidBlockStart())
{
return(null);
}
if (this.Output.Count == 0)
{
return(null);
}
// If previous line is just a newline, it is not a header
if (this.Output.Count >= 2 && this.Output.Last().Type == TokenType.NewLine && this.Output[this.Output.Count - 2].Type == TokenType.NewLine)
{
return(null);
}
string tokenval = "";
string tmp;
while ((tmp = this.PeekChar()) == lookahead || tmp == " ")
{
tokenval += this.ConsumeChar();
}
if ((tmp == NewLine || this.IsEndOfInput()) && tokenval.Length >= 4)
{
if (ctx.Peek)
{
this.Pointer -= tokenval.Length;
}
return(new Token {
Type = TokenType.HeaderStart, Value = tokenval
});
}
this.Pointer -= tokenval.Length;
return(null);
}
private Token CheckPreformatted(LexerContext ctx)
{
Token last = this.Output.LastOrDefault();
if (last != null && last.Type == TokenType.Indentation && this.CheckListItem(new LexerContext()
{
Peek = true
}) == null)
{
return new Token {
Type = TokenType.Preformatted, Value = ""
}
}
;
return(null);
}
private Token CheckIndentation(LexerContext ctx)
{
bool isValidBlockStart = this.IsValidBlockStart();
// Check tab
string lookahead = this.PeekChar();
if (isValidBlockStart && lookahead == Indent)
{
if (!ctx.Peek)
{
this.ConsumeChar();
}
return(new Token {
Type = TokenType.Indentation, Value = " "
});
}
// Check at least 4 white spaces
lookahead = PeekChar(4);
// If lookahead is null or it does not contain at least 4 chars, it is not a pre node
if (lookahead == null || lookahead.Length < 4)
{
return(null);
}
// Cannot start a pre node if it is not a valid block start
if (!isValidBlockStart)
{
return(null);
}
// If all chars are white space and are not new lines, it is an indent token
if (lookahead.All(c => char.IsWhiteSpace(c) && c != '\n'))
{
return new Token {
Type = TokenType.Indentation, Value = ctx.Peek ? lookahead : this.ConsumeChar(4)
}
}
;
return(null);
}
private Token CheckThematicBreak(LexerContext ctx)
{
if (!this.IsValidBlockStart())
{
return(null);
}
string lookahead = this.PeekChar(ThematicBreak.Length);
if (lookahead == ThematicBreak)
{
return new Token {
Type = TokenType.ThematicBreak, Value = ctx.Peek ? lookahead : this.ConsumeChar(ThematicBreak.Length)
}
}
;
return(null);
}
private Token CheckBlockquote(LexerContext ctx)
{
if (!this.IsValidBlockStart())
{
return(null);
}
string lookahead = this.PeekChar();
if (lookahead != Blockquote)
{
return(null);
}
int q = 1;
string tmp = null;
lookahead = "";
do
{
if (this.IsEndOfInput(q))
{
break;
}
tmp = this.PeekChar(q);
if (tmp[q - 1] == Blockquote[0])
{
q++;
lookahead = tmp;
continue;
}
break;
} while (true);
return(new Token {
Type = TokenType.Blockquote,
Value = ctx.Peek ? lookahead : this.ConsumeChar(Math.Max(1, q - 1))
});
}
private Token CheckBold(LexerContext ctx)
{
string lookahead = this.PeekChar();
if (lookahead == BoldOpen)
{
return new Token {
Type = TokenType.BoldOpen, Value = ctx.Peek ? lookahead : this.ConsumeChar()
}
}
;
if (lookahead == BoldClose)
{
return new Token {
Type = TokenType.BoldClose, Value = ctx.Peek ? lookahead : this.ConsumeChar()
}
}
;
return(null);
}
private Token CheckNumberedListItem(LexerContext ctx)
{
if (!this.IsValidBlockStart())
{
return(null);
}
int i = 1;
string lookahead = "";
while ((lookahead = this.PeekChar(i)).Length > 0 && !this.IsEndOfInput(i) && lookahead.All(c => char.IsDigit(c)))
{
i++;
}
string tmp = this.PeekChar(++i); // The NOT digit that broke the previos while plus the needed space
if (tmp == lookahead) // End of file
{
return(null);
}
if (tmp.EndsWith(". ") || tmp.EndsWith(") "))
{
lookahead = "# ";
if (!ctx.Peek)
{
this.ConsumeChar(i);
}
return(new Token {
Type = TokenType.ListItem, Value = lookahead, OriginalValue = tmp
});
}
return(null);
}
private Token CheckNewline(LexerContext ctx)
{
var lookahead = this.PeekChar(DoubleNewLine.Length);
if (lookahead == DoubleNewLine)
{
return new Token {
Type = TokenType.DoubleNewLine, Value = ctx.Peek ? lookahead : this.ConsumeChar(DoubleNewLine.Length)
}
}
;
lookahead = this.PeekChar();
if (lookahead == NewLine)
{
return(new Token {
Type = TokenType.NewLine, Value = ctx.Peek ? lookahead : this.ConsumeChar()
});
}
return(null);
}
private Token CheckImage(LexerContext ctx)
{
string lookahead = this.PeekChar(ImgOpen.Length);
bool lastIsEscape = this.LastIs(TokenType.Escape);
if (lookahead == ImgOpen && !lastIsEscape)
{
return new Token {
Type = TokenType.ImageStart, Value = ctx.Peek ? lookahead : this.ConsumeChar(ImgOpen.Length)
}
}
;
if (lookahead == ImgClose && !lastIsEscape)
{
return new Token {
Type = TokenType.ImageEnd, Value = ctx.Peek ? lookahead : this.ConsumeChar(ImgClose.Length)
}
}
;
return(null);
}
private Token NextMarkupToken(LexerContext ctx)
{
if (this.PeekChar() == null)
{
return(null);
}
return(this.CheckNewline(ctx)
// Block
?? this.CheckIndentation(ctx)
?? this.CheckThematicBreak(ctx)
?? this.CheckListItem(ctx)
?? this.CheckTodoListItem(ctx)
?? this.CheckNumberedListItem(ctx)
?? this.CheckLabeledListItem(ctx)
?? this.CheckPreformatted(ctx)
?? this.CheckBlockquote(ctx)
?? this.CheckHeader(ctx)
?? this.CheckCodeBlock(ctx)
?? this.CheckDmlCodeBlock(ctx)
?? this.CheckCodeBlockLang(ctx)
?? this.CheckEscapeBlock(ctx)
?? this.CheckReference(ctx)
// Inline elements
?? this.CheckLt(ctx)
?? this.CheckEscape(ctx)
?? this.CheckColon(ctx)
?? this.CheckPipe(ctx)
?? this.CheckLink(ctx)
?? this.CheckImage(ctx)
?? this.CheckBold(ctx)
?? this.CheckInlineCode(ctx)
?? this.CheckItalic(ctx)
?? this.CheckUnderlined(ctx)
?? this.CheckStrikethrough(ctx));
}
