using Microsoft.VisualStudio.TestTools.UnitTesting;
using System.Collections.Generic;
using System.Text;

namespace IrcTokens.Tests
{
    [TestClass]
    public class StatefulDecoder
    {
        private IrcTokens.StatefulDecoder _decoder;

        [TestInitialize]
        public void TestInitialize()
        {
            _decoder = new IrcTokens.StatefulDecoder();
        }

        [TestMethod]
        public void TestPartial()
        {
            var lines = _decoder.Push("PRIVMSG ");
            Assert.AreEqual(0, lines.Count);

            lines = _decoder.Push("#channel hello\r\n");
            Assert.AreEqual(1, lines.Count);

            var line = new Line("PRIVMSG #channel hello");
            CollectionAssert.AreEqual(new List<Line> { line }, lines);
        }

        [TestMethod]
        public void TestMultiple()
        {
            var lines = _decoder.Push("PRIVMSG #channel1 hello\r\nPRIVMSG #channel2 hello\r\n");
            Assert.AreEqual(2, lines.Count);

            var line1 = new Line("PRIVMSG #channel1 hello");
            var line2 = new Line("PRIVMSG #channel2 hello");
            Assert.AreEqual(line1, lines[0]);
            Assert.AreEqual(line2, lines[1]);
        }

        [TestMethod]
        public void TestEncoding()
        {
            var iso8859 = Encoding.GetEncoding("iso-8859-1");
            _decoder = new IrcTokens.StatefulDecoder { Encoding = iso8859 };
            var lines = _decoder.Push(iso8859.GetBytes("PRIVMSG #channel :hello Ç\r\n"));
            var line = new Line("PRIVMSG #channel :hello Ç");
            Assert.IsTrue(line.Equals(lines[0]));
        }

        [TestMethod]
        public void TestEncodingFallback()
        {
            var latin1 = Encoding.GetEncoding("iso-8859-1");
            _decoder = new IrcTokens.StatefulDecoder { Encoding = null, Fallback = latin1 };
            var lines = _decoder.Push(latin1.GetBytes("PRIVMSG #channel hélló\r\n"));
            Assert.AreEqual(1, lines.Count);
            Assert.IsTrue(new Line("PRIVMSG #channel hélló").Equals(lines[0]));
        }

        [TestMethod]
        public void TestEmpty()
        {
            var lines = _decoder.Push(string.Empty);
            Assert.IsNull(lines);
        }

        [TestMethod]
        public void TestBufferUnfinished()
        {
            _decoder.Push("PRIVMSG #channel hello");
            var lines = _decoder.Push(string.Empty);
            Assert.IsNull(lines);
        }

        [TestMethod]
        public void TestClear()
        {
            _decoder.Push("PRIVMSG ");
            _decoder.Clear();
            Assert.AreEqual(string.Empty, _decoder.Pending);
        }
    }
}