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/signal.hpp>
  21
  22 namespace lyx {
  23
  24 namespace support { class FileName; }
  25
  26 namespace graphics {
  27
  28 class Converter {
  29 public:
  30         /// Can the conversion be performed?
  31         static bool isReachable(std::string const & from_format_name,
  32                                 std::string const & to_format_name);
  33
  34         /** One Converter per conversion ensures that the (hidden) signal
  35          *  is always connected to the expected slot.
  36          */
  37         Converter(support::FileName const & from_file, std::string const & to_file_base,
  38                   std::string const & from_format, std::string const & to_format);
  39
  40         /// Needed for the pimpl
  41         ~Converter();
  42
  43         /// We are explicit about when we begin the conversion process.
  44         void startConversion() const;
  45
  46         /** Connect and you'll be informed when the conversion process has
  47          *  finished.
  48          *  If the conversion is succesful, then the listener is passed \c true.
  49          */
  50         typedef boost::signal<void(bool)> sig_type;
  51         typedef sig_type::slot_type slot_type;
  52         ///
  53         boost::signals::connection connect(slot_type const &) const;
  54
  55         /** If the conversion is succesful, this returns the name of the
  56          *  resulting file.
  57          *  If conversion fails or has not been completed, however, it
  58          *  returns an empty string.
  59          */
  60         support::FileName const & convertedFile() const;
  61
  62 private:
  63         /// noncopyable
  64         Converter(Converter const &);
  65         void operator=(Converter const &);
  66
  67         /// Use the Pimpl idiom to hide the internals.
  68         class Impl;
  69         /// The pointer never changes although *pimpl_'s contents may.
  70         Impl * const pimpl_;
  71 };
  72
  73 } // namespace graphics
  74 } // namespace lyx
  75
  76 #endif // GRAPHICSCONVERTER_H