public void VerifyChecksumsAndRebuild()
{
var original = File.ReadAllBytes(path);
var data = (byte[])original.Clone();
(data.Length % 4).Should().Be(0);
var drp = new DrpArchive(data);
drp.FileCount.Should().NotBe(0);
var mainSeed = BitConverter.ToUInt32(data, 0x04);
var mainChk = DrpArchiveWriter.GetHeaderSeed(drp);
mainSeed.Should().Be(mainChk);
var seed = BitConverter.ToUInt32(data, 0x94);
var chk = Crc32.ComputeChecksum(drp.Files[0].GetData());
seed.Should().Be(chk);
using var ms = new MemoryStream(original.Length);
drp.Write(ms);
var result = ms.ToArray();
result.Length.Should().Be(original.Length);
result.SequenceEqual(original).Should().BeTrue();
}
public void VerifyMutate()
{
var original = File.ReadAllBytes(path);
var data = (byte[])original.Clone();
(data.Length % 4).Should().Be(0);
var drp = new DrpArchive(data);
drp.FileCount.Should().NotBe(0);
// Zero out all arrays, keep original data on the side.
var old = drp.Files.Select(z => z.GetData()).ToArray();
for (int i = 0; i < drp.FileCount; i++)
{
drp.Files[i].SetData(new byte[old[i].Length]);
}
using var ms = new MemoryStream(original.Length);
drp.Write(ms);
var result = ms.ToArray();
result.Length.Should().BeLessThan(original.Length); // Compression of zeroes is more compact
result.SequenceEqual(original).Should().BeFalse(); // Different data ^
// Restore original data to modified drp, verify matches original drp
drp = new DrpArchive(result);
for (int i = 0; i < drp.FileCount; i++)
{
drp.Files[i].SetData(old[i]);
}
using var ms2 = new MemoryStream(original.Length);
drp.Write(ms2);
var result2 = ms2.ToArray();
result2.Length.Should().Be(original.Length);
result2.SequenceEqual(original).Should().BeTrue();
}
