using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using BizHawk.Common.StringExtensions;
// the HawkFile class is excessively engineered with the IHawkFileArchiveHandler to decouple the archive handling from the basic file handling.
// This is so we could drop in an unamanged dearchiver library optionally later as a performance optimization without ruining the portability of the code.
// Also, we want to be able to use HawkFiles in BizHawk.Common withuot bringing in a large 7-zip dependency
namespace BizHawk.Common
{
// TODO:
// split into "bind" and "open (the bound thing)"
// scan archive to flatten interior directories down to a path (maintain our own archive item list)
/// <summary>
/// Bridge between HawkFile and the frontend's implementation of archive management
/// </summary>
public interface IHawkFileArchiveHandler : IDisposable
{
// TODO - could this receive a hawkfile itself? possibly handy, in very clever scenarios of mounting fake files
bool CheckSignature(string fileName, out int offset, out bool isExecutable);
List<HawkFileArchiveItem> Scan();
IHawkFileArchiveHandler Construct(string path);
void ExtractFile(int index, Stream stream);
}
/// <summary>
/// HawkFile allows a variety of objects (actual files, archive members) to be treated as normal filesystem objects to be opened, closed, and read.
/// It can understand paths in 'canonical' format which includes /path/to/archive.zip|member.rom as well as /path/to/file.rom
/// When opening an archive, it won't always be clear automatically which member should actually be used.
/// Therefore there is a concept of 'binding' where a HawkFile attaches itself to an archive member which is the file that it will actually be using.
/// </summary>
public sealed class HawkFile : IDisposable
{
private bool _exists;
private bool _rootExists;
private string _rootPath;
private string _memberPath;
private Stream _rootStream, _boundStream;
private IHawkFileArchiveHandler _extractor;
private bool _isArchive;
private List<HawkFileArchiveItem> _archiveItems;
private int? _boundIndex;
public HawkFile() { }
/// <summary>
/// Set this with an instance which can construct archive handlers as necessary for archive handling.
/// </summary>
public static IHawkFileArchiveHandler ArchiveHandlerFactory { get; set; }
/// <summary>
/// Gets a value indicating whether a bound file exists. if there is no bound file, it can't exist.
/// NOTE: this isn't set until the file is Opened. Not too great...
/// </summary>
public bool Exists { get { return _exists; } }
/// <summary>
/// Gets the directory containing the root
/// </summary>
public string Directory { get { return Path.GetDirectoryName(_rootPath); } }
/// <summary>
/// Gets a value indicating whether this instance is bound
/// </summary>
public bool IsBound { get { return _boundStream != null; } }
/// <summary>
/// returns the complete canonical full path ("c:\path\to\archive|member") of the bound file
/// </summary>
public string CanonicalFullPath { get { return MakeCanonicalName(_rootPath, _memberPath); } }
/// <summary>
/// returns the complete canonical name ("archive|member") of the bound file
/// </summary>
public string CanonicalName { get { return MakeCanonicalName(Path.GetFileName(_rootPath), _memberPath); } }
/// <summary>
/// returns the virtual name of the bound file (disregarding the archive)
/// </summary>
public string Name { get { return GetBoundNameFromCanonical(MakeCanonicalName(_rootPath, _memberPath)); } }
/// <summary>
/// returns the complete full path of the bound file, excluding the archive member portion
/// </summary>
public string FullPathWithoutMember { get { return _rootPath; } }
/// <summary>
/// returns the member path part of the bound file
/// </summary>
public string ArchiveMemberPath { get { return _memberPath; } }
/// <summary>
/// returns the extension of Name
/// </summary>
public string Extension { get { return Path.GetExtension(Name).ToUpper(); } }
/// <summary>
/// Indicates whether this file is an archive
/// </summary>
public bool IsArchive { get { return _isArchive; } }
/// <summary>
/// Indicates whether the file is an archive member (IsArchive && IsBound[to member])
/// </summary>
public bool IsArchiveMember { get { return IsArchive && IsBound; } }
public IList<HawkFileArchiveItem> ArchiveItems
{
get
{
if (!IsArchive)
{
throw new InvalidOperationException("Cant get archive items from non-archive");
}
return _archiveItems;
}
}
/// <summary>
/// returns a stream for the currently bound file
/// </summary>
public Stream GetStream()
{
if (_boundStream == null)
{
throw new InvalidOperationException("HawkFile: Can't call GetStream() before youve successfully bound something!");
}
return _boundStream;
}
public int? GetBoundIndex()
{
return _boundIndex;
}
/// <summary>
/// Utility: Uses full HawkFile processing to determine whether a file exists at the provided path
/// </summary>
public static bool ExistsAt(string path)
{
using (var file = new HawkFile(path))
{
return file.Exists;
}
}
/// <summary>
/// Utility: attempts to read all the content from the provided path.
/// </summary>
public static byte[] ReadAllBytes(string path)
{
using (var file = new HawkFile(path))
{
if (!file.Exists)
{
throw new FileNotFoundException(path);
}
using (Stream stream = file.GetStream())
{
var ms = new MemoryStream((int)stream.Length);
stream.CopyTo(ms);
return ms.GetBuffer();
}
}
}
/// <summary>
/// attempts to read all the content from the file
/// </summary>
public byte[] ReadAllBytes()
{
using (Stream stream = GetStream())
{
var ms = new MemoryStream((int)stream.Length);
stream.CopyTo(ms);
return ms.GetBuffer();
}
}
/// <summary>
/// these extensions won't even be tried as archives (removes spurious archive detects since some of the signatures are pretty damn weak)
/// </summary>
public string[] NonArchiveExtensions = { ".smc", ".sfc", ".dll" };
/// <summary>
/// Parses the given filename to create an un-opened HawkFile with some information available about its path constitution
/// </summary>
public void Parse(string path)
{
bool isArchivePath = IsCanonicalArchivePath(path);
if (isArchivePath)
{
var parts = path.Split('|');
path = parts[0];
_memberPath = parts[1];
//we're gonna assume, on parsing, that this is
_isArchive = true;
}
_rootPath = path;
}
/// <summary>
/// Parses the given filename and then opens it. This may take a while (the archive may be accessed and scanned).
/// </summary>
public void Open(string path)
{
if (_rootPath != null)
{
throw new InvalidOperationException("Don't reopen a HawkFile.");
}
string autobind = null;
bool isArchivePath = IsCanonicalArchivePath(path);
if (isArchivePath)
{
var parts = path.Split('|');
path = parts[0];
autobind = parts[1];
}
var fi = new FileInfo(path);
_rootExists = fi.Exists;
if (fi.Exists == false)
{
return;
}
_rootPath = path;
_exists = true;
AnalyzeArchive(path);
if (_extractor == null)
{
_rootStream = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read);
// we could autobind here, but i dont want to
// bind it later with the desired extensions.
}
if (autobind == null)
{
// non-archive files can be automatically bound this way
if (!isArchivePath)
{
BindRoot();
}
}
else
{
autobind = autobind.ToUpperInvariant();
if (_extractor != null)
{
var scanResults = _extractor.Scan();
for (int i = 0; i < scanResults.Count; i++)
{
if (scanResults[i].Name.ToUpperInvariant() == autobind)
{
BindArchiveMember(i);
return;
}
}
}
_exists = false;
}
}
/// <summary>
/// Makes a new HawkFile based on the provided path.
/// </summary>
public HawkFile(string path)
{
Open(path);
}
/// <summary>
/// binds the specified ArchiveItem which you should have gotten by interrogating an archive hawkfile
/// </summary>
public HawkFile BindArchiveMember(HawkFileArchiveItem item)
{
return BindArchiveMember(item.Index);
}
/// <summary>
/// finds an ArchiveItem with the specified name (path) within the archive; returns null if it doesnt exist
/// </summary>
public HawkFileArchiveItem FindArchiveMember(string name)
{
return ArchiveItems.FirstOrDefault(ai => ai.Name == name);
}
/// <summary>
/// binds a path within the archive; returns null if that path didnt exist.
/// </summary>
public HawkFile BindArchiveMember(string name)
{
var ai = FindArchiveMember(name);
if (ai == null)
{
return null;
}
return BindArchiveMember(ai);
}
/// <summary>
/// binds the selected archive index
/// </summary>
public HawkFile BindArchiveMember(int index)
{
if (!_rootExists)
{
return this;
}
if (_boundStream != null)
{
throw new InvalidOperationException("stream already bound!");
}
_boundStream = new MemoryStream();
int archiveIndex = _archiveItems[index].ArchiveIndex;
_extractor.ExtractFile(archiveIndex, _boundStream);
_boundStream.Position = 0;
_memberPath = _archiveItems[index].Name; // TODO - maybe go through our own list of names? maybe not, its indexes dont match..
Console.WriteLine("HawkFile bound " + CanonicalFullPath);
_boundIndex = archiveIndex;
return this;
}
/// <summary>
/// Removes any existing binding
/// </summary>
public void Unbind()
{
if (_boundStream != null && _boundStream != _rootStream)
{
_boundStream.Close();
}
_boundStream = null;
_memberPath = null;
_boundIndex = null;
}
/// <summary>
/// causes the root to be bound (in the case of non-archive files)
/// </summary>
private void BindRoot()
{
_boundStream = _rootStream;
Console.WriteLine("HawkFile bound " + CanonicalFullPath);
}
/// <summary>
/// Binds the first item in the archive (or the file itself). Supposing that there is anything in the archive.
/// </summary>
public HawkFile BindFirst()
{
BindFirstOf();
return this;
}
/// <summary>
/// binds one of the supplied extensions if there is only one match in the archive
/// </summary>
public HawkFile BindSoleItemOf(params string[] extensions)
{
return BindByExtensionCore(false, extensions);
}
/// <summary>
/// Binds the first item in the archive (or the file itself) if the extension matches one of the supplied templates.
/// You probably should not use use BindSoleItemOf or the archive chooser instead
/// </summary>
public HawkFile BindFirstOf(params string[] extensions)
{
return BindByExtensionCore(true, extensions);
}
private HawkFile BindByExtensionCore(bool first, params string[] extensions)
{
if (!_rootExists)
{
return this;
}
if (_boundStream != null)
{
throw new InvalidOperationException("stream already bound!");
}
if (_extractor == null)
{
// open uncompressed file
var extension = Path.GetExtension(_rootPath).Substring(1).ToUpperInvariant();
if (extensions.Length == 0 || extension.In(extensions))
{
BindRoot();
}
return this;
}
var candidates = new List<int>();
for (int i = 0; i < _archiveItems.Count; i++)
{
var e = _archiveItems[i];
var extension = Path.GetExtension(e.Name).ToUpperInvariant();
extension = extension.TrimStart('.');
if (extensions.Length == 0 || extension.In(extensions))
{
if (first)
{
BindArchiveMember(i);
return this;
}
candidates.Add(i);
}
}
if (candidates.Count == 1)
{
BindArchiveMember(candidates[0]);
}
return this;
}
private void ScanArchive()
{
_archiveItems = _extractor.Scan();
}
private void AnalyzeArchive(string path)
{
// no archive handler == no analysis
if (ArchiveHandlerFactory == null)
{
return;
}
int offset;
bool isExecutable;
if (NonArchiveExtensions.Any(ext => Path.GetExtension(path).ToLower() == ext.ToLower()))
{
return;
}
if (ArchiveHandlerFactory.CheckSignature(path, out offset, out isExecutable))
{
_extractor = ArchiveHandlerFactory.Construct(path);
try
{
ScanArchive();
_isArchive = true;
}
catch
{
_extractor.Dispose();
_extractor = null;
_archiveItems = null;
}
}
}
public void Dispose()
{
Unbind();
if (_extractor != null)
{
_extractor.Dispose();
}
if (_rootStream != null)
{
_rootStream.Dispose();
}
_extractor = null;
_rootStream = null;
}
/// <summary>
/// is the supplied path a canonical name including an archive?
/// </summary>
static bool IsCanonicalArchivePath(string path)
{
return path.IndexOf('|') != -1;
}
/// <summary>
/// Repairs paths from an archive which contain offensive characters
/// </summary>
public static string Util_FixArchiveFilename(string fn)
{
return fn.Replace('\\', '/');
}
/// <summary>
/// converts a canonical name to a bound name (the bound part, whether or not it is an archive)
/// </summary>
static string GetBoundNameFromCanonical(string canonical)
{
var parts = canonical.Split('|');
return parts[parts.Length - 1];
}
/// <summary>
/// makes a canonical name from two parts
/// </summary>
string MakeCanonicalName(string root, string member)
{
if (member == null)
{
return root;
}
return string.Format("{0}|{1}", root, member);
}
}
/// <summary>
/// Members returned by IHawkFileArchiveHandler
/// </summary>
public class HawkFileArchiveItem
{
/// <summary>
/// Gets or sets the member name
/// </summary>
public string Name { get; set; }
/// <summary>
/// Gets or sets the size of member file
/// </summary>
public long Size { get; set; }
/// <summary>
/// Gets or sets the index of this archive item
/// </summary>
public int Index { get; set; }
/// <summary>
/// Gets or sets the index WITHIN THE ARCHIVE (for internal tracking by a IHawkFileArchiveHandler) of the member
/// </summary>
public int ArchiveIndex { get; set; }
}
}
