public static Paragraph Parse(string text, Style?style = null)
{
if (text is null)
{
throw new ArgumentNullException(nameof(text));
}
style ??= Style.Plain;
var result = new Paragraph();
using var tokenizer = new MarkupTokenizer(text);
var stack = new Stack <Style>();
while (tokenizer.MoveNext())
{
var token = tokenizer.Current;
if (token == null)
{
break;
}
if (token.Kind == MarkupTokenKind.Open)
{
var parsedStyle = StyleParser.Parse(token.Value);
stack.Push(parsedStyle);
}
else if (token.Kind == MarkupTokenKind.Close)
{
if (stack.Count == 0)
{
throw new InvalidOperationException($"Encountered closing tag when none was expected near position {token.Position}.");
}
stack.Pop();
}
else if (token.Kind == MarkupTokenKind.Text)
{
// Get the effective style.
var effectiveStyle = style.Combine(stack.Reverse());
result.Append(Emoji.Replace(token.Value), effectiveStyle);
}
else
{
throw new InvalidOperationException("Encountered unknown markup token.");
}
}
if (stack.Count > 0)
{
throw new InvalidOperationException("Unbalanced markup stack. Did you forget to close a tag?");
}
return(result);
}
/// <summary>
/// Removes markup from the specified string.
/// </summary>
/// <param name="text">The text to remove markup from.</param>
/// <returns>A string that does not have any markup.</returns>
public static string RemoveMarkup(this string?text)
{
if (string.IsNullOrWhiteSpace(text))
{
return(string.Empty);
}
var result = new StringBuilder();
var tokenizer = new MarkupTokenizer(text);
while (tokenizer.MoveNext() && tokenizer.Current != null)
{
if (tokenizer.Current.Kind == MarkupTokenKind.Text)
{
result.Append(tokenizer.Current.Value);
}
}
return(result.ToString());
}