wxWidgets/include/wx/filesys.h

/////////////////////////////////////////////////////////////////////////////
// Name:        filesys.h
// Purpose:     class for opening files - virtual file system
// Author:      Vaclav Slavik
// Copyright:   (c) 1999 Vaclav Slavik
// RCS-ID:      $Id$
// Licence:     wxWindows Licence
/////////////////////////////////////////////////////////////////////////////

#ifndef __FILESYS_H__
#define __FILESYS_H__

#ifdef __GNUG__
#pragma interface
#endif

#include "wx/setup.h"

#if !wxUSE_STREAMS
#error You cannot compile virtual file systems without wxUSE_STREAMS
#endif

#if wxUSE_HTML && !wxUSE_FILESYSTEM
#error You cannot compile wxHTML without virtual file systems
#endif

#if wxUSE_FILESYSTEM

#include "wx/stream.h"
#include "wx/url.h"
#include "wx/datetime.h"

class wxFSFile;
class wxFileSystemHandler;
class wxFileSystem;

//--------------------------------------------------------------------------------
// wxFSFile
//                  This class is a file opened using wxFileSystem. It consists of
//                  input stream, location, mime type & optional anchor
//                  (in 'index.htm#chapter2', 'chapter2' is anchor)
//--------------------------------------------------------------------------------

class WXDLLEXPORT wxFSFile : public wxObject
{
public:
    wxFSFile(wxInputStream *stream, const wxString& loc, 
             const wxString& mimetype, const wxString& anchor,
             wxDateTime modif)
    {
        m_Stream = stream;
        m_Location = loc;
        m_MimeType = mimetype; m_MimeType.MakeLower();
        m_Anchor = anchor;
        m_Modif = modif;
    }
    virtual ~wxFSFile() { if (m_Stream) delete m_Stream; }

    // returns stream. This doesn't _create_ stream, it only returns
    // pointer to it!!
    wxInputStream *GetStream() const {return m_Stream;}

    // returns file's mime type
    const wxString& GetMimeType() const {return m_MimeType;}

    // returns the original location (aka filename) of the file
    const wxString& GetLocation() const {return m_Location;}

    const wxString& GetAnchor() const {return m_Anchor;}

    wxDateTime GetModificationTime() const {return m_Modif;}

private:
    wxInputStream *m_Stream;
    wxString m_Location;
    wxString m_MimeType;
    wxString m_Anchor;
    wxDateTime m_Modif;
};





//--------------------------------------------------------------------------------
// wxFileSystemHandler
//                  This class is FS handler for wxFileSystem. It provides
//                  interface to access certain
//                  kinds of files (HTPP, FTP, local, tar.gz etc..)
//--------------------------------------------------------------------------------

class WXDLLEXPORT wxFileSystemHandler : public wxObject
{
public:
    wxFileSystemHandler() : wxObject() {}

    // returns TRUE if this handler is able to open given location
    virtual bool CanOpen(const wxString& location) = 0;

    // opens given file and returns pointer to input stream.
    // Returns NULL if opening failed.
    // The location is always absolute path.
    virtual wxFSFile* OpenFile(wxFileSystem& fs, const wxString& location) = 0;

    // Finds first/next file that matches spec wildcard. flags can be wxDIR for restricting
    // the query to directories or wxFILE for files only or 0 for either.
    // Returns filename or empty string if no more matching file exists
    virtual wxString FindFirst(const wxString& spec, int flags = 0);
    virtual wxString FindNext();

protected:
    // returns protocol ("file", "http", "tar" etc.) The last (most right)
    // protocol is used:
    // {it returns "tar" for "file:subdir/archive.tar.gz#tar:/README.txt"}
    wxString GetProtocol(const wxString& location) const;

    // returns left part of address:
    // {it returns "file:subdir/archive.tar.gz" for "file:subdir/archive.tar.gz#tar:/README.txt"}
    wxString GetLeftLocation(const wxString& location) const;

    // returns anchor part of address:
    // {it returns "anchor" for "file:subdir/archive.tar.gz#tar:/README.txt#anchor"}
    // NOTE:  anchor is NOT a part of GetLeftLocation()'s return value
    wxString GetAnchor(const wxString& location) const;

    // returns right part of address:
    // {it returns "/README.txt" for "file:subdir/archive.tar.gz#tar:/README.txt"}
    wxString GetRightLocation(const wxString& location) const;

    // Returns MIME type of the file - w/o need to open it
    // (default behaviour is that it returns type based on extension)
    wxString GetMimeTypeFromExt(const wxString& location);

    DECLARE_ABSTRACT_CLASS(wxFileSystemHandler)
};




//--------------------------------------------------------------------------------
// wxFileSystem
//                  This class provides simple interface for opening various
//                  kinds of files (HTPP, FTP, local, tar.gz etc..)
//--------------------------------------------------------------------------------

class WXDLLEXPORT wxFileSystem : public wxObject
{
public:
    wxFileSystem() : wxObject() {m_Path = m_LastName = wxEmptyString; m_Handlers.DeleteContents(TRUE); m_FindFileHandler = NULL;}

    // sets the current location. Every call to OpenFile is
    // relative to this location.
    // NOTE !!
    // unless is_dir = TRUE 'location' is *not* the directory but
    // file contained in this directory
    // (so ChangePathTo("dir/subdir/xh.htm") sets m_Path to "dir/subdir/")
    void ChangePathTo(const wxString& location, bool is_dir = FALSE);

    wxString GetPath() const {return m_Path;}

    // opens given file and returns pointer to input stream.
    // Returns NULL if opening failed.
    // It first tries to open the file in relative scope
    // (based on ChangePathTo()'s value) and then as an absolute
    // path.
    wxFSFile* OpenFile(const wxString& location);

    // Finds first/next file that matches spec wildcard. flags can be wxDIR for restricting
    // the query to directories or wxFILE for files only or 0 for either.
    // Returns filename or empty string if no more matching file exists
    wxString FindFirst(const wxString& spec, int flags = 0);
    wxString FindNext();

    // Adds FS handler.
    // In fact, this class is only front-end to the FS hanlers :-)
    static void AddHandler(wxFileSystemHandler *handler);

    // remove all items from the m_Handlers list
    static void CleanUpHandlers();

protected:
    wxString m_Path;
            // the path (location) we are currently in
            // this is path, not file!
            // (so if you opened test/demo.htm, it is
            // "test/", not "test/demo.htm")
    wxString m_LastName;
            // name of last opened file (full path)
    static wxList m_Handlers;
            // list of FS handlers
    wxFileSystemHandler *m_FindFileHandler;
            // handler that succeed in FindFirst query

    DECLARE_DYNAMIC_CLASS(wxFileSystem)
};


/*

'location' syntax:

To determine FS type, we're using standard KDE notation:
file:/absolute/path/file.htm
file:relative_path/xxxxx.html
/some/path/x.file               ('file:' is default)
http://www.gnome.org
file:subdir/archive.tar.gz#tar:/README.txt

special characters :
  ':' - FS identificator is before this char
  '#' - separator. It can be either HTML anchor ("index.html#news")
            (in case there is no ':' in the string to the right from it)
        or FS separator
            (example : http://www.wxhtml.org/wxhtml-0.1.tar.gz#tar:/include/wxhtml/filesys.h"
             this would access tgz archive stored on web)
  '/' - directory (path) separator. It is used to determine upper-level path.
        HEY! Don't use \ even if you're on Windows!

*/


class wxLocalFSHandler : public wxFileSystemHandler
{
public:
    virtual bool CanOpen(const wxString& location);
    virtual wxFSFile* OpenFile(wxFileSystem& fs, const wxString& location);
    virtual wxString FindFirst(const wxString& spec, int flags = 0);
    virtual wxString FindNext();
    
    // wxLocalFSHandler will prefix all filenames with 'root' before accessing
    // files on disk. This effectively makes 'root' the top-level directory
    // and prevents access to files outside this directory.  
    // (This is similar to Unix command 'chroot'.)
    static void Chroot(const wxString& root) { ms_root = root; }
    
protected:
    static wxString ms_root;
};



#endif
  // wxUSE_FILESYSTEM

#endif
  // __FILESYS_H__