ircsharp / IRCTokens / StatefulEncoder.cs

using System.Text;

// ReSharper disable ReplaceWithFieldKeyword

namespace IRCTokens;

public class StatefulEncoder
{
    private List<Line> _bufferedLines;
    private Encoding _encoding;

    public StatefulEncoder()
    {
        Clear();
    }

    public Encoding Encoding
    {
        get => _encoding ?? Encoding.GetEncoding(
            Encoding.UTF8.CodePage,
            EncoderFallback.ExceptionFallback,
            DecoderFallback.ExceptionFallback);
        set
        {
            if (value != null)
            {
                _encoding = Encoding.GetEncoding(
                    value.CodePage,
                    EncoderFallback.ExceptionFallback,
                    DecoderFallback.ExceptionFallback);
            }
        }
    }

    public byte[] PendingBytes { get; private set; }

    public string Pending()
    {
        try
        {
            return Encoding.GetString(PendingBytes);
        }
        catch (DecoderFallbackException e)
        {
            Console.WriteLine(e);
            throw;
        }
    }

    public void Clear()
    {
        PendingBytes   = [];
        _bufferedLines = [];
    }

    public void Push(Line line)
    {
        if (line == null)
        {
            throw new ArgumentNullException(nameof(line));
        }

        PendingBytes = PendingBytes.Concat(Encoding.GetBytes($"{line.Format()}\r\n")).ToArray();
        _bufferedLines.Add(line);
    }

    public List<Line> Pop(int byteCount)
    {
        var sent = PendingBytes.Take(byteCount).Count(c => c == '\n');

        PendingBytes = PendingBytes.Skip(byteCount).ToArray();

        var sentLines = _bufferedLines.Take(sent).ToList();
        _bufferedLines = _bufferedLines.Skip(sent).ToList();

        return sentLines;
    }
}