/// <summary>
/// Can automatically decompress XML if it is compressed
/// </summary>
/// <param name="raw"></param>
/// <returns></returns>
public static string AutoXml(string raw)
{
try
{
//validation
if (!string.IsNullOrEmpty(raw))
{
//test for validity
var isAlreadyXml = IsValidXml(raw);
//run accordingly
if (isAlreadyXml)
{
return(raw);
}
else
{
//decompression may now be required
var decompressed = GZipCompressor.DecompressString(raw);
//test for XML validity
if (IsValidXml(decompressed))
{
return(decompressed);
}
}
}
}
catch (Exception)
{
//nothing
}
//default
return(@"");
}
/// <summary>
/// Create a new record from a GZipped Base64 string
/// </summary>
/// <param name="compressedRaw">The raw representation of the PxzRecord to load</param>
/// <returns></returns>
public static PxzRecord FromRawForm(string compressedRaw)
{
var decompressedXml = GZipCompressor.DecompressString(compressedRaw);
return(Serializers.StringToPxzRecord(decompressedXml));
}
/// <summary>
/// Load an existing PXZ file from disk
/// </summary>
/// <param name="path">The file to load</param>
public void Load(string path)
{
try
{
//can't load a non-existent file
if (!System.IO.File.Exists(path))
{
return;
}
//clear all lists and assign the new location
Location = path;
Records.Clear();
FileIndex.RecordReference.Clear();
//item names to load
const string idxName = @"index";
const string dirName = @"records";
//read the PXZ file into memory
using var zip = ZipFile.Read(path);
//load the raw file index into memory
var idxFile = zip[idxName];
//the index can't be null!
if (idxFile == null)
{
if (!ParseSilent)
{
UIMessages.Error(@"PXZ index couldn't be found or it isn't valid");
}
return;
}
//raw gzip index string (base64)
string idxString;
//extract and save the index to a new stream
using (var idxStream = new MemoryStream())
{
idxFile.Extract(idxStream); //ERROR LINE
idxStream.Position = 0;
idxString = new StreamReader(idxStream).ReadToEnd();
}
//Gzip decompress
var idxByte = GZipCompressor.DecompressString(idxString);
var index = Serializers.StringToPxzIndex(idxByte);
//if this gets flipped to true, it's potentially bad news
var tamperedWith = false;
//load all records into memory
foreach (var recFile in index.RecordReference.Select(
r => $"{dirName}/{r.StoredName}")
.Select(recName => zip[recName]))
{
//byte stream for the raw record
using var recStream = new MemoryStream();
//grab data from the file and store in memory
recFile.Extract(recStream);
recStream.Position = 0;
//open a new reader for the memory block
using var reader = new StreamReader(recStream);
//jump through the memory stream and turn it into Base64
var recRaw = reader.ReadToEnd();
//serialise rawXml into a usable PxzRecord
var rec = PxzRecord.FromRawForm(recRaw);
//sync Encrypted with ProtectedRecord (native object can't do this)
rec.ProtectedRecord = rec.Content.Encrypted;
//verify checksums on the record to ensure authenticity
tamperedWith = !rec.ChecksumValid;
//finally, index and store the record
Records.Add(rec);
FileIndex.RecordReference.Add(rec.Header.Naming);
}
//apply new values
FileIndex = index;
//check authenticity flag, and warn if it's been altered
if (tamperedWith)
{
if (!ParseSilent)
{
UIMessages.Warning("Content has been modified\n\nThe MD5 checksums stored do not match the checksums calculated, which is an indication that the contents may have been altered outside of the PXZ handler. The file will continue loading after you close this message.");
}
}
}
catch (Exception ex)
{
if (!ParseSilent)
{
UIMessages.Error(ex.ToString());
}
}
}
