/// <summary>
/// Reads the given ggpk archive <paramref name="stream"/> and returns all records.
/// </summary>
/// <param name="stream">The ggpk <see cref="Stream"/>.</param>
/// <returns>All records read from the <see cref="Stream"/>.</returns>
/// <exception cref="ArgumentNullException"><c>stream</c> is <c>null</c>.</exception>
/// <exception cref="GgpkException">Error while reading the archive.</exception>
public static IEnumerable <GgpkRecord> From(Stream stream)
{
if (stream is null)
{
throw new ArgumentNullException(nameof(stream));
}
List <GgpkRecord> records = new List <GgpkRecord>();
using (BinaryReader ggpkStreamReader = new BinaryReader(stream))
{
try
{
while (ggpkStreamReader.BaseStream.Position < ggpkStreamReader.BaseStream.Length)
{
GgpkRecordMarker recordMarker = GgpkRecordMarker.From(ggpkStreamReader);
GgpkRecord currentRecord = null;
if (recordMarker.Offset + recordMarker.Length > (ulong)ggpkStreamReader.BaseStream.Length)
{
throw new InvalidDataException($"Invalid record length {recordMarker.Length} at offset {recordMarker.Offset}");
}
switch (recordMarker.Type)
{
case "GGPK":
currentRecord = GgpkMainRecord.From(ggpkStreamReader);
break;
case "FREE":
currentRecord = GgpkFreeRecord.From(recordMarker, ggpkStreamReader);
break;
case "FILE":
currentRecord = GgpkFileRecord.From(recordMarker, ggpkStreamReader);
break;
case "PDIR":
currentRecord = GgpkDirectoryRecord.From(ggpkStreamReader);
break;
default:
throw new InvalidDataException($"Unknown record type {recordMarker.Type} at offset {recordMarker.Offset}");
}
currentRecord.Offset = recordMarker.Offset;
currentRecord.Length = recordMarker.Length;
records.Add(currentRecord);
}
}
catch (Exception ex)
{
throw new GgpkException($"Error while parsing the ggpk archive file", ex)
{
Offset = ggpkStreamReader.BaseStream.Position
};
}
}
return(records);
}
/// <summary>
/// Builds the directory and file tree.
/// </summary>
/// <param name="currentDirectory">The current directory.</param>
/// <param name="currentDirectoryContent">The desired content of the current directory.</param>
/// <param name="records">All <see cref="GgpkRecord">records</see> from the ggpk archive used to find the references.</param>
private void BuildDirectoryTree(
GgpkDirectory currentDirectory,
IEnumerable <GgpkDirectoryRecordEntry> currentDirectoryContent,
IDictionary <ulong, GgpkRecord> records)
{
foreach (GgpkDirectoryRecordEntry recordEntry in currentDirectoryContent)
{
GgpkRecord referencedRecord = records[recordEntry.Offset];
if (referencedRecord is null)
{
throw new GgpkException($"Error while analyzing the ggpk archive file: no element found at offset {recordEntry.Offset}");
}
switch (referencedRecord)
{
case GgpkDirectoryRecord directoryRecord:
GgpkDirectory directory = new GgpkDirectory()
{
Name = directoryRecord.DirectoryName,
TimeStamp = recordEntry.TimeStamp,
Hash = directoryRecord.Hash,
Parent = currentDirectory,
ArchiveFileName = this.FileName
};
if (currentDirectory != null)
{
currentDirectory.Add(directory);
}
else
{
this.root = directory;
}
this.BuildDirectoryTree(directory, directoryRecord.Entries, records);
break;
case GgpkFileRecord fileRecord:
GgpkFile file = new GgpkFile()
{
Name = fileRecord.FileName,
TimeStamp = recordEntry.TimeStamp,
Hash = fileRecord.Hash,
Offset = fileRecord.FileOffset,
Length = fileRecord.FileLength,
Parent = currentDirectory,
ArchiveFileName = this.FileName
};
currentDirectory.Add(file);
break;
case GgpkFreeRecord freeRecord:
break;
default:
throw new GgpkException($"Error while analyzing the ggpk archive file: no element of type directory or file found at offset {recordEntry.Offset}");
}
}
}
