better checks of import/export settings

rowers/views/userviews.py

@@ -298,6 +298,17 @@ def rower_favoritecharts_view(request,userid=0):
 @login_required()
 @permission_required('rower.is_coach',fn=get_user_by_userid,raise_exception=True)
 def rower_exportsettings_view(request,userid=0):
+    attrtokens = {
+        'polar_auto_import':'polartoken',
+        'c2_auto_export':'c2token',
+        'c2_auto_import':'c2token',
+        'mapmyfitness_auto_export':'underarmourtoken',
+        'runkeeper_auto_export':'runkeepertoken',
+        'sporttracks_auto_export':'sporttrackstoken',
+        'strava_auto_export':'stravatoken',
+        'strava_auto_import':'stravatoken',
+        'trainingpeaks_auto_export':'tptoken',
+    }
     r = getrequestrower(request,userid=userid)
     if request.method == 'POST':
         form = RowerExportForm(request.POST)
@@ -305,7 +316,21 @@ def rower_exportsettings_view(request,userid=0):
             cd = form.cleaned_data
 
             for attr, value in cd.items():
-                setattr(r, attr, value)
+                doset = True
+                try:
+                    tokenname = attrtokens[attr]
+                    if getattr(r, tokenname) == '' or getattr(r, tokenname) == None:
+                        doset = False
+                except KeyError:
+                    doset = True
+                if not doset:
+                    before = getattr(r,attr)
+                    if before == value:
+                        doset = True
+                if doset:
+                    setattr(r, attr, value)
+                else:
+                    messages.error(request,'Could not set '+attr+'. You need to create the connection first.')
 
             r.save()
             messages.info(request,'Settings saved')