src/graphics/GraphicsConverter.h

   1 // -*- C++ -*-
   2 /**
   3  * \file GraphicsConverter.h
   4  * This file is part of LyX, the document processor.
   5  * Licence details can be found in the file COPYING.
   6  *
   7  * \author Angus Leeming
   8  *
   9  * Full author contact details are available in file CREDITS.
  10  *
  11  * The controller of a conversion process from file AA of format A to
  12  * file BB of format B.
  13  * Once finished, a signal is emitted to inform any listeners (connected
  14  * through the connect() method).
  15  */
  16
  17 #ifndef GRAPHICSCONVERTER_H
  18 #define GRAPHICSCONVERTER_H
  19
  20 #include <boost/scoped_ptr.hpp>
  21 #include <boost/signal.hpp>
  22 #include <boost/utility.hpp>
  23
  24 namespace lyx {
  25 namespace graphics {
  26
  27 class Converter : boost::noncopyable {
  28 public:
  29         /// Can the conversion be performed?
  30         static bool isReachable(std::string const & from_format_name,
  31                                 std::string const & to_format_name);
  32
  33         /** One Converter per conversion ensures that the (hidden) signal
  34          *  is always connected to the expected slot.
  35          */
  36         Converter(std::string const & from_file,   std::string const & to_file_base,
  37                   std::string const & from_format, std::string const & to_format);
  38
  39         /// Define an empty d-tor out-of-line to keep boost::scoped_ptr happy.
  40         ~Converter();
  41
  42         /// We are explicit about when we begin the conversion process.
  43         void startConversion() const;
  44
  45         /** Connect and you'll be informed when the conversion process has
  46          *  finished.
  47          *  If the conversion is succesful, then the listener is passed \c true.
  48          */
  49         typedef boost::signal<void(bool)> sig_type;
  50         typedef sig_type::slot_type slot_type;
  51         ///
  52         boost::signals::connection connect(slot_type const &) const;
  53
  54         /** If the conversion is succesful, this returns the name of the
  55          *  resulting file.
  56          *  If conversion fails or has not been completed, however, it
  57          *  returns an empty string.
  58          */
  59         std::string const & convertedFile() const;
  60
  61 private:
  62         /// Use the Pimpl idiom to hide the internals.
  63         class Impl;
  64
  65         /// The pointer never changes although *pimpl_'s contents may.
  66         boost::scoped_ptr<Impl> const pimpl_;
  67 };
  68
  69 } // namespace graphics
  70 } // namespace lyx
  71
  72 #endif // GRAPHICSCONVERTER_H