using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace AMWD.Common.Extensions
{
	public static class StreamExtensions
	{
		public static string ReadLine(this Stream stream, Encoding encoding = null, string eol = null)
		{
			if (encoding == null)
				encoding = Encoding.Default;

			if (eol == null)
				eol = Environment.NewLine;

			if (!stream.CanRead)
				return null;

			var bytes = new List<byte>();
			string s;
			do
			{
				int result = stream.ReadByte();
				if (result == -1)
					break;

				byte b = (byte)result;
				bytes.Add(b);
				s = encoding.GetString(new[] { b });
			}
			while (!eol.Contains(s));

			return encoding.GetString(bytes.ToArray()).Trim();
		}

		public static async Task<string> ReadLineAsync(this Stream stream, Encoding encoding = null, string eol = null, CancellationToken cancellationToken = default)
		{
			if (encoding == null)
				encoding = Encoding.Default;

			if (eol == null)
				eol = Environment.NewLine;

			if (!stream.CanRead)
				return null;

			var bytes = new List<byte>();
			string s;
			do
			{
				byte[] buffer = new byte[1];
				int count = await stream.ReadAsync(buffer, 0, buffer.Length);
				if (count == 0)
					break;

				bytes.Add(buffer[0]);
				s = encoding.GetString(buffer);
			}
			while (!eol.Contains(s));

			return encoding.GetString(bytes.ToArray()).Trim();
		}
	}
}