IndentingTextWriter for C-style languages

IndentingTextWriter.cs

using System.Text;

namespace Sylvan.IO;

sealed class IndentingTextWriter : TextWriter
{
	const char OpenChar = '{';
	const char CloseChar = '}';
	const string DefaultIndent = "   ";

	readonly TextWriter inner;
	int level = 0;
	int pending = 0;
	bool skipWS = false; //skip user whitespace at the start of lines
	string indent;

	public IndentingTextWriter(TextWriter inner, string indent = DefaultIndent)
	{
		this.inner = inner;
		this.indent = indent;
	}

	public override void Flush()
	{
		inner.Flush();
	}

	public override Task FlushAsync()
	{
		return inner.FlushAsync();
	}

	public override Encoding Encoding => Encoding.UTF8;

	public override void Write(char value)
	{
		if (value == OpenChar)
		{
			level++;
		}
		if (value == CloseChar)
		{
			level--;
			pending--;
		}
		
		if (skipWS && (value == ' ' || value == '\t'))
		{
			// skip it
			return;
		}
		else
		{
			while (pending-- > 0)
			{
				inner.Write(indent);
			}
			inner.Write(value);
		}
		if (value == '\n')
		{
			pending = level;
			skipWS = true;
		}
		else
		{
			skipWS = false;
		}
	}

	protected override void Dispose(bool disposing)
	{
		if (disposing)
		{
			inner.Dispose();
		}
		base.Dispose(disposing);
	}
}