Added 5 minute interval align for time select buttons (#415)

* added 5 minute interval align for time select buttons

* fixed linting error

* fixed formatting error

* fixed formatting

timetagger/app/dialogs.py

@@ -878,6 +878,18 @@ def _get_time(self, what, fallback=True):
             hh, mm, ss = utils.timestr2tuple(self["ori_" + what])
         return hh, mm, ss
 
+    def _stepwise_delta(self, mm, delta):
+        if delta >= 0:
+            # delta is positiv, apply modulo with offset
+            return delta - (mm % delta)
+        else:
+            # delta is negative
+            mm_new = -(mm % -(delta))
+            if mm_new == 0:
+                # we are already at stepsize, just return delta
+                return delta
+            return mm_new
+
     def render(self):
         now = dt.now()
 
@@ -919,6 +931,9 @@ def render(self):
             self.date2input.style.color = None
 
     def onchanged(self, action):
+        # step size used for time buttons
+        _stepsize = 5
+
         now = dt.now()
 
         # Get node
@@ -986,9 +1001,9 @@ def onchanged(self, action):
             else:
                 hh, mm, ss = self._get_time("time1")
                 if option == "more":
-                    mm, ss = mm + 5, 0
+                    mm, ss = mm + self._stepwise_delta(mm, _stepsize), 0
                 elif option == "less":
-                    mm, ss = mm - 5, 0
+                    mm, ss = mm + self._stepwise_delta(mm, -(_stepsize)), 0
                 d1 = window.Date(year1, month1 - 1, day1, hh, mm, ss)
                 self.t1 = dt.to_time_int(d1)
                 if self.ori_t1 == self.ori_t2:
@@ -1008,9 +1023,9 @@ def onchanged(self, action):
             else:
                 hh, mm, ss = self._get_time("time2")
                 if option == "more":
-                    mm, ss = mm + 5, 0
+                    mm, ss = mm + self._stepwise_delta(mm, _stepsize), 0
                 elif option == "less":
-                    mm, ss = mm - 5, 0
+                    mm, ss = mm + self._stepwise_delta(mm, -(_stepsize)), 0
                 d2 = window.Date(year2, month2 - 1, day2, hh, mm, ss)
                 self.t2 = dt.to_time_int(d2)
                 if self.ori_t1 == self.ori_t2: