using Unity.SharpZipLib.BZip2;
using Unity.SharpZipLib.Tests.TestSupport;
using NUnit.Framework;
using System;
using System.IO;
namespace Unity.SharpZipLib.Tests.BZip2
{
    /// <summary>
    /// This class contains test cases for Bzip2 compression
    /// </summary>
    [TestFixture]
    internal class BZip2Suite
    {
        // Use the same random seed to guarantee all the code paths are followed
        const int RandomSeed = 4;

        /// <summary>
        /// Basic compress/decompress test BZip2
        /// </summary>
        [Test]
        [Category("BZip2")]
        public void BasicRoundTrip()
        {
            var ms = new MemoryStream();
            var outStream = new BZip2OutputStream(ms);
            byte[] buf = new byte[10000];
            var rnd = new Random(RandomSeed);
            rnd.NextBytes(buf);
            outStream.Write(buf, 0, buf.Length);
            outStream.Close();
            ms = new MemoryStream(ms.GetBuffer());
            ms.Seek(0, SeekOrigin.Begin);
            using (BZip2InputStream inStream = new BZip2InputStream(ms))
            {
                byte[] buf2 = new byte[buf.Length];
                int pos = 0;
                while (true)
                {
                    int numRead = inStream.Read(buf2, pos, 4096);
                    if (numRead <= 0)
                    {
                        break;
                    }
                    pos += numRead;
                }
                for (int i = 0; i < buf.Length; ++i)
                {
                    Assert.AreEqual(buf2[i], buf[i]);
                }
            }
        }
        /// <summary>
        /// Check that creating an empty archive is handled ok
        /// </summary>
        [Test]
        [Category("BZip2")]
        public void CreateEmptyArchive()
        {
            var ms = new MemoryStream();
            var outStream = new BZip2OutputStream(ms);
            outStream.Close();
            ms = new MemoryStream(ms.GetBuffer());
            ms.Seek(0, SeekOrigin.Begin);
            using (BZip2InputStream inStream = new BZip2InputStream(ms))
            {
                byte[] buffer = new byte[1024];
                int pos = 0;
                while (true)
                {
                    int numRead = inStream.Read(buffer, 0, buffer.Length);
                    if (numRead <= 0)
                    {
                        break;
                    }
                    pos += numRead;
                }
                Assert.Zero(pos);
            }
        }
        [Test]
        [Category("BZip2")]
        [Category("Performance")]
        [Explicit("Long-running")]
        public void WriteThroughput()
        {
            PerformanceTesting.TestWrite(
                size: TestDataSize.Small,
                output: w => new BZip2OutputStream(w)
            );
        }
        [Test]
        [Category("BZip2")]
        [Category("Performance")]
        [Explicit("Long-running")]
        public void ReadWriteThroughput()
        {
            PerformanceTesting.TestReadWrite(
                size: TestDataSize.Small,
                input: w => new BZip2InputStream(w),
                output: w => new BZip2OutputStream(w)
            );
        }
    }
}