Order sunrise and sunset according to current time

Before sunrise, first sunrise is shown and then sunset. After sunrise,
before sunset, first sunet is shown, and then tomorrow's sunrise. After
sunset, first sunrise is shown and then sunset, both for tomorrow.

bumblebee/modules/sun.py

@@ -15,6 +15,12 @@ try:
     import requests
 except ImportError:
     pass
+try:
+    from dateutil.tz import tzlocal
+except ImportError:
+    pass
+
+import datetime
 
 import bumblebee.input
 import bumblebee.output
@@ -43,11 +49,16 @@ class Module(bumblebee.engine.Module):
 
     def suntimes(self, _):
         if self._sunset and self._sunrise:
+            if self._isup:
+                return u"\u21A7{} \u21A5{}".format(
+                    self._sunset.strftime('%H:%M'),
+                    self._sunrise.strftime('%H:%M'))
             return u"\u21A5{} \u21A7{}".format(self._sunrise.strftime('%H:%M'),
                                                self._sunset.strftime('%H:%M'))
         return "?"
 
     def _calculate_times(self):
+        self._isup = False
         try:
             sun = Sun(self._lat, self._lon)
         except Exception:
@@ -55,15 +66,41 @@ class Module(bumblebee.engine.Module):
             self._sunset = None
             return
 
+        order_matters = True
+
         try:
             self._sunrise = sun.get_local_sunrise_time()
         except SunTimeException:
-            self._sunrise = 'no sunrise'
+            self._sunrise = "no sunrise"
+            order_matters = False
 
         try:
             self._sunset = sun.get_local_sunset_time()
         except SunTimeException:
-            self._sunset = 'no sunset'
+            self._sunset = "no sunset"
+            order_matters = False
+
+        if not order_matters:
+            return
+
+        now = datetime.datetime.now(tz=tzlocal())
+        if now > self._sunset:
+            tomorrow = (now + datetime.timedelta(days=1)).date()
+            try:
+                self._sunrise = sun.get_local_sunrise_time(tomorrow)
+                self._sunset = sun.get_local_sunset_time(tomorrow)
+            except SunTimeException:
+                self._sunrise = "no sunrise"
+                self._sunset = "no sunset"
+
+        elif now > self._sunrise:
+            tomorrow = (now + datetime.timedelta(days=1)).date()
+            try:
+                self._sunrise = sun.get_local_sunrise_time(tomorrow)
+            except SunTimeException:
+                self._sunrise = "no sunrise"
+                return
+            self._isup = True
 
     def update(self, widgets):
         if not self._lat or not self._lon: