using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using Xunit.Abstractions;

namespace MagicalUnicorns {
    public class XunitConsoleForwarder : TextWriter {
        private readonly ITestOutputHelper output;

        private IList<char> line = new List<char>();

        public XunitConsoleForwarder(ITestOutputHelper output) {
            this.output = output;
        }

        public override Encoding Encoding => Console.Out.Encoding;

        public override void Write(char value) {
            if (value == '\n') {
                FlushLine();
                line = new List<char>();
                return;
            }

            line.Add(value);
        }

        protected override void Dispose(bool disposing) {
            if (line.Count > 0) {
                FlushLine();
            }

            base.Dispose(disposing);
        }

        private void FlushLine() {
            if (line.Count > 0 && line.Last() == '\r') {
                line.RemoveAt(line.Count - 1);
            }

            output.WriteLine(new string(line.ToArray()));
        }
    }
}