private static void ReplaceFilesInArchive(DrpArchive drp, IEnumerable <string> filesToReplace)
{
foreach (var f in filesToReplace)
{
ReplaceFile(drp, f);
}
}
private static DrpArchive Replace(string source, IEnumerable <string> filesToReplace)
{
var data = File.ReadAllBytes(source);
var drp = new DrpArchive(data);
ReplaceFilesInArchive(drp, filesToReplace);
return(drp);
}
/// <summary>
/// Writes the <see cref="archive"/> to the <see cref="output"/> stream.
/// </summary>
public static void Write(this DrpArchive archive, Stream output)
{
using var bw = new BinaryWriter(output);
var seed = GetHeaderSeed(archive);
bw.WriteHeader(archive, seed);
bw.WriteEntries(archive);
bw.WriteFooter(archive, seed);
}
private static void WriteEntries(this BinaryWriter bw, DrpArchive archive)
{
var files = archive.Files;
bool encrypted = archive.Encrypted;
var table = archive.SeedTable;
foreach (var f in files)
{
WriteEntry(bw, f, encrypted, table);
}
}
private static void ReplaceFileName(DrpArchive drp, string fileFullPath, string fn)
{
var entry = drp.GetFileEntry(fn);
if (entry is not null)
{
ReplaceEntry(entry, fileFullPath);
}
else
{
Console.WriteLine($"Unable to find file in the input drp archive: {fn}");
}
}
private static void WriteHeader(this BinaryWriter bw, DrpArchive archive, uint seed)
{
bw.Write(DrpArchive.ArchiveHeaderMagic);
bw.Write(seed);
if (archive.Encrypted)
{
var rng = XorShiftUtil.GetEncryptionRng(seed, archive.SeedTable);
bw.Write(rng.GetNext(uint.MaxValue) ^ DrpArchive.CryptoBlockMagic);
bw.Write(rng.GetNext(uint.MaxValue) ^ 0x90u);
bw.Write(rng.GetNext(uint.MaxValue) ^ (uint)archive.FileCount);
}
else
{
bw.Write(DrpArchive.CryptoBlockMagic);
bw.Write(0x90u);
bw.Write(archive.FileCount);
}
bw.Write(archive.SeedTable);
}
private static void WriteFooter(this BinaryWriter bw, DrpArchive archive, uint seed)
{
var asUint = MemoryMarshal.Cast <byte, uint>(archive.Footer);
if (archive.Encrypted)
{
var rng = XorShiftUtil.GetEncryptionRng(seed, archive.SeedTable);
foreach (var u32 in asUint)
{
bw.Write(u32 ^ rng.GetNext(uint.MaxValue));
}
}
else
{
foreach (var u32 in asUint)
{
bw.Write(u32);
}
}
}
private static void ReplaceFile(DrpArchive drp, string fileFullPath)
{
var fn = Path.GetFileName(fileFullPath);
ReplaceFileName(drp, fileFullPath, fn);
}