Fix GitHub Issue #13: Implement MIDI file export

- Exports tempo track, note on/off, velocity

Author: juzzlin

CHANGELOG

@@ -5,6 +5,9 @@ Release date:
 
 New features:
 
+* Fix GitHub Issue #13: Implement MIDI file export
+  - Exports tempo track, note on/off, velocity
+
 * Add percentage interpolation to velocity dialog
 
 Bug fixes:

src/CMakeLists.txt

@@ -68,6 +68,7 @@ set(HEADER_FILES
   domain/track.hpp
   infra/audio/audio_recorder.hpp
   infra/audio/implementation/librtaudio/audio_recorder_rt_audio.hpp
+  infra/midi/export/midi_exporter.hpp
   infra/midi/implementation/librtmidi/midi_in_rt_midi.hpp
   infra/midi/implementation/librtmidi/midi_out_rt_midi.hpp
   infra/midi/midi.hpp
@@ -144,6 +145,7 @@ set(SOURCE_FILES
   domain/song.cpp
   domain/track.cpp
   infra/audio/audio_recorder.cpp
+  infra/midi/export/midi_exporter.cpp
   infra/audio/implementation/librtaudio/audio_recorder_rt_audio.cpp
   infra/midi/implementation/librtmidi/midi_in_rt_midi.cpp
   infra/midi/implementation/librtmidi/midi_out_rt_midi.cpp

src/application/application.cpp

@@ -17,6 +17,7 @@
 
 #include "../contrib/Argengine/src/argengine.hpp"
 #include "../contrib/SimpleLogger/src/simple_logger.hpp"
+#include "../infra/midi/export/midi_exporter.hpp"
 #include "../infra/video/video_generator.hpp"
 #include "common/utils.hpp"
 #include "domain/midi_note_data.hpp"
@@ -67,6 +68,7 @@ Application::Application(int & argc, char ** argv)
   , m_selectionService { std::make_unique<SelectionService>() }
   , m_editorService { std::make_unique<EditorService>(m_selectionService) }
   , m_eventSelectionModel { std::make_unique<EventSelectionModel>() }
+  , m_midiExporter { std::make_unique<MidiExporter>(m_automationService) }
   , m_midiService { std::make_unique<MidiService>() }
   , m_mixerService { std::make_unique<MixerService>() }
   , m_playerService { std::make_unique<PlayerService>(m_midiService, m_mixerService, m_automationService, m_settingsService) }
@@ -258,6 +260,21 @@ void Application::connectApplicationService()
     connect(m_applicationService.get(), &ApplicationService::liveNoteOnRequested, m_midiService.get(), &MidiService::playNote);
     connect(m_applicationService.get(), &ApplicationService::liveNoteOffRequested, m_midiService.get(), &MidiService::stopNote);
     connect(m_applicationService.get(), &ApplicationService::allNotesOffRequested, this, &Application::stopAllNotes);
+
+    connect(m_applicationService.get(), &ApplicationService::midiExportRequested, this, &Application::exportToMidi);
+}
+
+void Application::exportToMidi(QString fileName)
+{
+    try {
+        m_midiExporter->exportTo(fileName.toStdString(), m_editorService->song());
+        const auto message = QString { "Exported the project to '%1' " }.arg(fileName);
+        m_applicationService->statusTextRequested(message);
+    } catch (std::exception & e) {
+        const auto message = QString { "Failed to export as MIDI: %1 " }.arg(e.what());
+        juzzlin::L(TAG).error() << message.toStdString();
+        m_applicationService->statusTextRequested(message);
+    }
 }
 
 void Application::connectAutomationService()

src/application/application.hpp

@@ -40,6 +40,7 @@ class EditorService;
 class EventSelectionModel;
 class Instrument;
 class MidiCcAutomationsModel;
+class MidiExporter;
 class MidiService;
 class MidiSettingsModel;
 class MixerService;
@@ -103,6 +104,8 @@ class Application : public QObject
     void requestInstruments(QStringList midiPorts);
     void stopAllNotes() const;
 
+    void exportToMidi(QString fileName);
+
     std::unique_ptr<UiLogger> m_uiLogger;
 
     std::unique_ptr<QGuiApplication> m_application;
@@ -119,6 +122,7 @@ class Application : public QObject
 
     std::shared_ptr<EventSelectionModel> m_eventSelectionModel;
 
+    std::shared_ptr<MidiExporter> m_midiExporter;
     std::shared_ptr<MidiService> m_midiService;
     std::shared_ptr<MixerService> m_mixerService;
     std::shared_ptr<PlayerService> m_playerService;

src/application/service/application_service.cpp

@@ -60,6 +60,11 @@ QString ApplicationService::fileFormatExtension() const
     return Constants::fileFormatExtension();
 }
 
+QString ApplicationService::midiFileExtension() const
+{
+    return Constants::midiFileExtension();
+}
+
 QString ApplicationService::webSiteUrl() const
 {
     return Constants::webSiteUrl();
@@ -132,6 +137,22 @@ void ApplicationService::requestSaveProjectAsTemplate()
     m_stateMachine->calculateState(StateMachine::Action::SaveProjectAsTemplateRequested);
 }
 
+void ApplicationService::requestMidiExportDialog()
+{
+    // No need to route through state machine as the current data can always be exported
+    juzzlin::L(TAG).info() << "MIDI export requested";
+    emit midiExportDialogRequested();
+}
+
+void ApplicationService::exportAsMidi(QUrl url)
+{
+    auto fileName = url.toLocalFile();
+    if (!fileName.endsWith(Constants::midiFileExtension())) {
+        fileName += Constants::midiFileExtension();
+    }
+    emit midiExportRequested(fileName);
+}
+
 void ApplicationService::requestLiveNoteOn(quint8 key, quint8 octave, quint8 velocity)
 {
     if (const auto instrument = m_editorService->instrument(m_editorService->position().track); instrument) {

src/application/service/application_service.hpp

@@ -45,6 +45,7 @@ class ApplicationService : public QObject
     Q_INVOKABLE QString applicationVersion() const;
     Q_INVOKABLE QString copyright() const;
     Q_INVOKABLE QString fileFormatExtension() const;
+    Q_INVOKABLE QString midiFileExtension() const;
     Q_INVOKABLE QString license() const;
     Q_INVOKABLE QString webSiteUrl() const;
 
@@ -83,6 +84,9 @@ class ApplicationService : public QObject
     Q_INVOKABLE void saveProjectAs(QUrl url);
     Q_INVOKABLE void saveProjectAsTemplate(QUrl url);
 
+    Q_INVOKABLE void requestMidiExportDialog();
+    Q_INVOKABLE void exportAsMidi(QUrl url);
+
     Q_INVOKABLE bool editMode() const;
     Q_INVOKABLE void setEditMode(bool editMode);
 
@@ -128,6 +132,8 @@ class ApplicationService : public QObject
 
     void saveAsDialogRequested();
     void saveAsTemplateDialogRequested();
+    void midiExportDialogRequested();
+    void midiExportRequested(QString fileName);
 
     void alertDialogRequested(QString message);
     void statusTextRequested(QString message);

src/common/constants.cpp

@@ -47,6 +47,11 @@ QString fileFormatExtension()
     return ".nahd";
 }
 
+QString midiFileExtension()
+{
+    return ".mid";
+}
+
 QString qSettingsCompanyName()
 {
     return applicationName();

src/common/constants.hpp

@@ -29,6 +29,7 @@ QString license();
 
 QString fileFormatVersion();
 QString fileFormatExtension();
+QString midiFileExtension();
 
 QString qSettingsCompanyName();
 QString qSettingSoftwareName();

src/domain/column.cpp

@@ -114,6 +114,7 @@ void Column::setNoteDataAtPosition(const NoteData & noteData, const Position & p
     juzzlin::L(TAG).debug() << "Set note data at position: " << noteData.toString() << " @ " << position.toString();
     auto newNoteData = noteData;
     newNoteData.setColumn(index());
+    newNoteData.setTrack(position.track); // Set the track from the position
     m_lines.at(static_cast<size_t>(position.line))->setNoteData(newNoteData);
 }
 

src/domain/line.cpp

@@ -60,10 +60,7 @@ void Line::setNoteData(const NoteData & noteData)
     *m_noteData = noteData;
 }
 
-Line::NoteDataS Line::noteData() const
-{
-    return m_noteData;
-}
+
 
 Line::LineEventOpt Line::lineEvent() const
 {
@@ -120,4 +117,9 @@ Line::LineU Line::deserializeFromXml(QXmlStreamReader & reader, size_t trackInde
     return line;
 }
 
+Line::NoteDataS Line::noteData() const
+{
+    return m_noteData;
+}
+
 } // namespace noteahead