/// <summary>
/// Asynchronously loads a NeFS archive from disk.
/// </summary>
/// <param name="filepath">The path to the .nefs file to load.</param>
/// <param name="p">Progress info for reporting progress.</param>
/// <returns></returns>
public static async Task <NefsArchive> LoadAsync(String filePath, NefsProgressInfo p)
{
// TODO : Move the async stuff to UI project like replace/save??
var archive = await Task.Run(() => {
try
{
log.Info("----------------------------");
log.Info(String.Format("Opening archive {0}...", filePath));
var ret = new NefsArchive(filePath, p);
log.Info("Archive opened successfully.");
return(ret);
}
catch (OperationCanceledException ex)
{
log.Info("Open archive operation cancelled.");
return(null);
}
catch (IOException ex)
{
log.Error(String.Format("An error occurred while reading the file {0}.", filePath), ex);
return(null);
}
});
return(archive);
}
/// <summary>
/// Loads a NeFS item with the specified id from the archive.
/// </summary>
/// <param name="file">The file stream to load from.</param>
/// <param name="archive">The NeFS archive this item is in.</param>
/// <param name="id">The id of the item in the archive to load.</param>
public NefsItem(FileStream file, NefsArchive archive, UInt32 id)
{
/* Validate inputs */
if (file == null)
{
throw new ArgumentNullException("File stream required to load NeFS item.");
}
if (archive == null)
{
throw new ArgumentNullException("NeFS archive object required to load an item.");
}
_archive = archive;
_id = id;
/* Get header entries related to this item */
_pt1Entry = archive.Header.Part1.GetEntry(id);
_pt2Entry = archive.Header.Part2.GetEntry(_pt1Entry);
_pt5Entry = archive.Header.Part5.GetEntry(id);
try
{
_pt6Entry = archive.Header.Part6.GetEntry(id);
}
catch (Exception ex)
{
try
{
/* Some items share a part 2 entry, so try to find the corresponding part 6 entry */
_pt6Entry = archive.Header.Part6.GetEntry(_pt2Entry.Id);
}
catch (Exception ex2)
{
// TODO : Handle when an item doesn't have a part 6 entry
_pt6Entry = archive.Header.Part6.GetEntry(0);
}
}
/* Determine item type */
_type = (_pt1Entry.OffsetToData == 0)
? NefsItemType.Directory
: NefsItemType.File;
/* Get the filename */
_fileName = archive.Header.Part3.GetFilename(_pt2Entry.FilenameOffset);
/* Hash the filename */
_fileNameHash = FilePathHelper.HashStringMD5(_fileName);
/* Get offsets */
_dataOffset = _pt1Entry.OffsetToData;
_offsetIntoPt2Raw = _pt1Entry.OffsetIntoPt2Raw;
_offsetIntoPt4Raw = _pt1Entry.OffsetIntoPt4Raw;
/* Get extracted size */
_extractedSize = _pt2Entry.ExtractedSize;
/*
* Build the file path inside this archive
* for example: "rootDir/childDir/file.xml".
*/
_filePathInArchive = _fileName;
var currentItem = _pt2Entry;
/* The root directory's id is equal to its parent directory id */
while (currentItem.Id != currentItem.DirectoryId)
{
var pt1Entry = archive.Header.Part1.GetEntry(currentItem.DirectoryId);
var dir = archive.Header.Part2.GetEntry(pt1Entry);
var dirName = archive.Header.Part3.GetFilename(dir.FilenameOffset);
_filePathInArchive = Path.Combine(dirName, _filePathInArchive);
currentItem = dir;
}
/* Hash the file path in archive */
_filePathInArchiveHash = FilePathHelper.HashStringMD5(_filePathInArchive);
//
// Get the compressed file chunk offsets
//
if (_pt1Entry.OffsetIntoPt4Raw == 0xFFFFFFFF)
{
// TODO : Not sure exactly what this value means yet
// For now, just set compressed size as extracted size with not compressed chunk sizes
_compressedSize = ExtractedSize;
}
else
{
var numChunks = (UInt32)Math.Ceiling(ExtractedSize / (double)CHUNK_SIZE);
if (numChunks > 0)
{
var firstChunkSizeEntry = _archive.Header.Part4.Offset + _pt1Entry.OffsetIntoPt4;
UInt32Type chunkOffset;
for (int i = 0; i < numChunks; i++)
{
chunkOffset = new UInt32Type(i * 4);
chunkOffset.Read(file, firstChunkSizeEntry);
_chunkSizes.Add(chunkOffset.Value);
}
_compressedSize = _chunkSizes.Last();
}
}
}