Python Embedding is optional and check install

.. make python embedding optional, if it's not installed then
   disable in preferences (new checkbox similar to R).

src/Core/Settings.h

@@ -98,6 +98,7 @@
 #define GC_HOMEDIR                      "<system>homedirectory"
 #define GC_START_HTTP                   "<system>starthttp"
 #define GC_EMBED_R                      "<system>embedR"
+#define GC_EMBED_PYTHON                 "<system>embedPython"
 
 #define GC_SETTINGS_LAST                "<system>mainwindow/lastOpened"
 #define GC_SETTINGS_MAIN_GEOM           "<system>mainwindow/geometry"

src/Core/main.cpp

@@ -437,7 +437,11 @@ main(int argc, char *argv[])
 #endif
 
 #ifdef GC_WANT_PYTHON
-        if (noPy == false && python == NULL) python = new PythonEmbed(); // initialise python in this thread ?
+        bool embed = appsettings->value(NULL, GC_EMBED_PYTHON, true).toBool();
+        if (embed && noPy == false && python == NULL) {
+            python = new PythonEmbed(); // initialise python in this thread ?
+            if (python->loaded == false) python=NULL;
+        }
 #endif
 
         //this is the path within the current directory where GC will look for

src/Gui/Pages.cpp

@@ -186,6 +186,13 @@ GeneralPage::GeneralPage(Context *context) : context(context)
     connect(embedR, SIGNAL(stateChanged(int)), this, SLOT(embedRchanged(int)));
 #endif
 
+#ifdef GC_WANT_PYTHON
+    embedPython = new QCheckBox(tr("Enable Python"), this);
+    embedPython->setChecked(appsettings->value(NULL, GC_EMBED_PYTHON, true).toBool());
+    configLayout->addWidget(embedPython, 7+offset,1, Qt::AlignLeft);
+    offset += 1;
+#endif
+
     //
     // Athlete directory (home of athletes)
     //
@@ -305,6 +312,9 @@ GeneralPage::saveClicked()
 #ifdef GC_WANT_R
     appsettings->setValue(GC_EMBED_R, embedR->isChecked());
 #endif
+#ifdef GC_WANT_PYTHON
+    appsettings->setValue(GC_EMBED_PYTHON, embedPython->isChecked());
+#endif
 
     qint32 state=0;
 

src/Gui/Pages.h

@@ -105,6 +105,9 @@ class GeneralPage : public QWidget
 #endif
 #ifdef GC_WANT_R
         QCheckBox *embedR;
+#endif
+#ifdef GC_WANT_PYTHON
+        QCheckBox *embedPython;
 #endif
         QLineEdit *garminHWMarkedit;
         QLineEdit *hystedit;

src/Python/PythonEmbed.cpp

@@ -62,6 +62,19 @@ PythonEmbed::PythonEmbed(const bool verbose, const bool interactive) : verbose(v
 
     // set the module path in the same way the interpreter would
     PyObject *sys = PyImport_ImportModule("sys");
+
+    // did module import fail (python not installed)
+    if (sys == NULL) {
+
+        // abort embedding
+        QMessageBox msg(QMessageBox::Information, QObject::tr("Python not installed"),
+                    QObject::tr("Python v3.6 or higher is required for Python.\nPython disabled in preferences."));
+        appsettings->setValue(GC_EMBED_PYTHON, false);
+        loaded=false;
+        msg.exec();
+        return;
+    }
+
     PyObject *path = PyObject_GetAttrString(sys, "path");
     PyList_Append(path, PyUnicode_FromString("."));