Improve clock management

- tick() implemented independently of Config.TIMER_MS
 - have tick() call periodic functions
 - don't rely on vlc get_time() (too coarse)

app/config.py

@@ -69,7 +69,6 @@ class Config(object):
     MAX_MISSING_FILES_TO_REPORT = 10
     MILLISECOND_SIGFIGS = 0
     MINIMUM_ROW_HEIGHT = 30
-    MYSQL_CONNECT = os.environ.get('MYSQL_CONNECT') or "mysql+mysqldb://musicmuster:musicmuster@localhost/musicmuster_v2"  # noqa E501
     NOTE_TIME_FORMAT = "%H:%M:%S"
     OBS_HOST = "localhost"
     OBS_PASSWORD = "auster"

app/music.py

@@ -91,14 +91,6 @@ class Music:
         fader = FadeTrack(p)
         pool.start(fader)
 
-    def get_playtime(self) -> Optional[int]:
-        """Return elapsed play time"""
-
-        if not self.player:
-            return None
-
-        return self.player.get_time()
-
     def get_position(self) -> Optional[float]:
         """Return current position"""
 

app/musicmuster.py

@@ -915,6 +915,24 @@ class Window(QMainWindow, Ui_MainWindow):
         else:
             return None
 
+    def get_playtime(self) -> int:
+        """
+        Return number of milliseconds current track has been playing or
+        zero if not playing. The vlc function get_time() only updates 3-4
+        times a second; this function has much better resolution.
+        """
+
+        if (
+            self.current_track.track_id is None or
+            self.current_track.start_time is None
+        ):
+            return 0
+
+        now = datetime.now()
+        track_start = self.current_track.start_time
+        elapsed_seconds = (now - track_start).total_seconds()
+        return int(elapsed_seconds * 1000)
+
     def hide_played(self):
         """Toggle hide played tracks"""
 
@@ -1671,29 +1689,25 @@ class Window(QMainWindow, Ui_MainWindow):
 
     def tick(self) -> None:
         """
-        Carry out clock tick actions.
+        Called every Config.TIMER_MS milliseconds. Call periodic functions
+        as required.
+        """
 
-        self.clock_counter is incrememted at each tick (100ms), and this
+        # Get current number of milliseconds
-        value is used to determine the actions to take.
+        self.clock_counter += Config.TIMER_MS
+        self.clock_counter %= 1000
 
-        The Fade Volume graph is updated every 10ms.
+        # Call periodic functions
+        if self.clock_counter % 10 == 0:
+            self.tick_10ms()
+        if self.clock_counter % 500 == 0:
+            self.tick_500ms()
+        if self.clock_counter == 0:
+            self.tick_1000ms()
 
-        The Time of Day clock and any cart progress bars are updated
+    def tick_10ms(self) -> None:
-        every 500ms.
+        """
-
+        Called every 10ms
-        All other timers are updated every second. As the timer displays
-        have a one-second resolution, updating every 500ms can result in
-        some timers updating and then, 500ms later, other timers
-        updating. That looks odd.
-
-        Actions required:
-        - Update Fade Volume graph
-        - Update TOD clock
-        - Call cart_tick
-        - If track is playing:
-            update track clocks time and colours
-        - Else:
-            run stop_track
         """
 
         # Update volume fade curve
@@ -1707,14 +1721,24 @@ class Window(QMainWindow, Ui_MainWindow):
             ).total_seconds() * 1000
             self.current_track.fade_graph.tick(play_time)
 
-        if self.clock_counter % 20 == 0:
+    def tick_500ms(self) -> None:
-            # Update TOD clock
+        """
+        Called every 500ms
+        """
+
         self.lblTOD.setText(datetime.now().strftime(
             Config.TOD_TIME_FORMAT))
         # Update carts
         self.cart_tick()
 
-        if self.clock_counter % 50 == 0:
+    def tick_1000ms(self) -> None:
+        """
+        Called every 1000ms
+        """
+
+        # Only update play clocks once a second so that their updates
+        # are synchronised (otherwise it looks odd)
+
         if not self.playing:
             return
 
@@ -1727,7 +1751,7 @@ class Window(QMainWindow, Ui_MainWindow):
                 self.music.player.is_playing() or
                 (datetime.now() - self.current_track.start_time)
                 < timedelta(microseconds=Config.PLAY_SETTLE)):
-                playtime = self.music.get_playtime()
+            playtime = self.get_playtime()
             time_to_fade = (self.current_track.fade_at - playtime)
             time_to_silence = (
                     self.current_track.silence_at - playtime)