refactor: use branded types in runtimestate

apps/client/src/common/components/multi-part-progress-bar/MultiPartProgressBar.tsx

@@ -9,7 +9,6 @@ import './MultiPartProgressBar.scss';
 interface MultiPartProgressBar {
   now: MaybeNumber;
   complete: MaybeNumber;
-  eventId?: string | null;
   normalColor: string;
   warning?: MaybeNumber;
   warningColor: string;
@@ -25,7 +24,6 @@ export default function MultiPartProgressBar(props: MultiPartProgressBar) {
   const {
     now,
     complete,
-    eventId,
     normalColor,
     warning,
     warningColor,
@@ -37,7 +35,7 @@ export default function MultiPartProgressBar(props: MultiPartProgressBar) {
     className = '',
   } = props;
 
-  const percentRemaining = 100 - useAnimatedProgress(now, complete, eventId);
+  const percentRemaining = 100 - useAnimatedProgress(now, complete);
   const dangerWidth = danger ? 100 - getProgress(danger, complete) : 0;
   const warningWidth = warning ? 100 - dangerWidth - getProgress(warning, complete) : 0;
   const isOvertime = now !== null && now < 0;

apps/client/src/common/components/progress-bar/ProgressBar.tsx

@@ -7,12 +7,12 @@ import './ProgressBar.scss';
 interface ProgressBarProps {
   current: MaybeNumber;
   duration: MaybeNumber;
-  eventId?: string | null;
   className?: string;
 }
 
-export default function ProgressBar({ current, duration, eventId, className }: ProgressBarProps) {
+export default function ProgressBar(props: ProgressBarProps) {
-  const progress = useAnimatedProgress(current, duration, eventId);
+  const { current, duration, className } = props;
+  const progress = useAnimatedProgress(current, duration);
 
   return (
     <div className={`progress-bar__bg ${className}`}>

apps/client/src/common/hooks/useAnimatedProgress.ts

@@ -1,34 +1,26 @@
-import { EntryId, MaybeNumber, Playback } from 'ontime-types';
+import { MaybeNumber, Playback } from 'ontime-types';
 import { useEffect, useRef, useState } from 'react';
 
 import { getProgress } from '../utils/getProgress';
-import { useIsOnline, usePlayback } from './useSocket';
+import { usePlayback } from './useSocket';
 
 /**
  * Returns the live completion percentage (0–100) of a countdown, interpolated locally.
  */
-export function useAnimatedProgress(current: MaybeNumber, duration: MaybeNumber, eventId?: EntryId | null): number {
+export function useAnimatedProgress(current: MaybeNumber, duration: MaybeNumber): number {
   const playback = usePlayback();
-  const isOnline = useIsOnline();
   const isRunning = playback === Playback.Play || playback === Playback.Roll;
 
-  const baseline = useRef({ current, duration, eventId, playback, at: performance.now() });
+  const baseline = useRef({ current, at: performance.now() });
   const [, setTick] = useState(0);
-  const now = performance.now();
 
-  const hasAuthoritativeUpdate =
+  // there is only something to animate while a running timer is counting down towards 0
-    baseline.current.current !== current || // handle timer updates
+  const shouldAnimate = isRunning && current !== null && current > 0 && duration !== null;
-    baseline.current.duration !== duration || // handle duration changes
-    baseline.current.eventId !== eventId || // handle event changing
-    baseline.current.playback !== playback; // handle playback changes
 
-  if (hasAuthoritativeUpdate) {
+  // re-anchor to the authoritative value whenever the server pushes a new timer update
-    // Reset during render so an event change is reflected in this very paint.
+  useEffect(() => {
-    baseline.current = { current, duration, eventId, playback, at: now };
+    baseline.current = { current, at: performance.now() };
-  }
+  }, [current, duration, playback]);
-
-  // There is only something to animate while a connected timer is counting down towards 0.
-  const shouldAnimate = isOnline && isRunning && current !== null && current > 0 && duration !== null;
 
   // while counting down, re-render every animation frame so the derived progress stays smooth
   useEffect(() => {
@@ -42,8 +34,8 @@ export function useAnimatedProgress(current: MaybeNumber, duration: MaybeNumber,
     return () => cancelAnimationFrame(frame);
   }, [shouldAnimate]);
 
-  // Derive from the anchor plus elapsed time at render; freeze while disconnected or not running.
+  // derive from the anchor plus elapsed time at render; frozen to the anchor when not running
   const anchored = baseline.current.current;
-  const value = isOnline && isRunning && anchored !== null ? anchored - (now - baseline.current.at) : anchored;
+  const value = isRunning && anchored !== null ? anchored - (performance.now() - baseline.current.at) : anchored;
   return getProgress(value, duration);
 }

apps/client/src/common/hooks/useSocket.ts

@@ -163,7 +163,6 @@ export const useNextFlag = createSelector((state: RuntimeStore) => ({
 export const useProgressData = createSelector((state: RuntimeStore) => ({
   current: state.timer.current,
   duration: state.timer.duration,
-  eventId: state.eventNow?.id ?? null,
   timeWarning: state.eventNow?.timeWarning ?? null,
   timeDanger: state.eventNow?.timeDanger ?? null,
 }));

apps/client/src/features/operator/status-bar/StatusBarProgress.tsx

@@ -10,13 +10,12 @@ interface StatusBarProgressProps {
 }
 
 export default function StatusBarProgress({ viewSettings }: StatusBarProgressProps) {
-  const { current, duration, eventId, timeWarning, timeDanger } = useProgressData();
+  const { current, duration, timeWarning, timeDanger } = useProgressData();
 
   return (
     <MultiPartProgressBar
       now={current}
       complete={duration}
-      eventId={eventId}
       normalColor={viewSettings.normalColor}
       warning={timeWarning}
       warningColor={viewSettings.warningColor}

apps/client/src/features/rundown/rundown-event/composite/RundownEventProgressBar.tsx

@@ -1,13 +1,12 @@
 import { useAnimatedProgress } from '../../../../common/hooks/useAnimatedProgress';
-import { useSelectedEventId, useTimer } from '../../../../common/hooks/useSocket';
+import { useTimer } from '../../../../common/hooks/useSocket';
 
 import style from './RundownEventProgressBar.module.scss';
 
 export default function RundownEventProgressBar() {
   const timer = useTimer();
-  const eventId = useSelectedEventId();
 
-  const progress = useAnimatedProgress(timer.current, timer.duration, eventId);
+  const progress = useAnimatedProgress(timer.current, timer.duration);
 
   return <div className={style.progressBar} style={{ width: `${progress}%` }} />;
 }

apps/client/src/views/backstage/Backstage.tsx

@@ -112,14 +112,7 @@ function Backstage({ events, customFields, projectData, isMirrored, settings }:
         <BackstageClock timeformat={timeformat} />
       </div>
 
-      {showProgress && (
+      {showProgress && <ProgressBar className='progress-container' current={time.current} duration={time.duration} />}
-        <ProgressBar
-          className='progress-container'
-          current={time.current}
-          duration={time.duration}
-          eventId={selectedEventId}
-        />
-      )}
 
       {!hasEvents && <Empty text={getLocalizedString('common.no_data')} className='empty-container' />}
 

apps/client/src/views/cuesheet/cuesheet-progress/CuesheetProgress.tsx

@@ -6,13 +6,12 @@ import styles from './CuesheetProgress.module.scss';
 
 export default function CuesheetProgress() {
   const { data } = useViewSettings();
-  const { current, duration, eventId, timeWarning, timeDanger } = useProgressData();
+  const { current, duration, timeWarning, timeDanger } = useProgressData();
 
   return (
     <MultiPartProgressBar
       now={current}
       complete={duration}
-      eventId={eventId}
       normalColor={data.normalColor}
       warning={timeWarning}
       warningColor={data.warningColor}

apps/client/src/views/editor/pip-timer/PipTimer.tsx

@@ -96,7 +96,6 @@ export function PipTimer({ viewSettings }: PipTimerProps) {
           className={cx(['progress-container', !isPlaying && 'progress-container--paused'])}
           now={time.current}
           complete={totalTime}
-          eventId={eventNow?.id}
           normalColor={viewSettings.normalColor}
           warning={eventNow?.timeWarning}
           warningColor={viewSettings.warningColor}

apps/client/src/views/timeline/TimelineEntry.tsx

@@ -2,7 +2,7 @@ import { Day } from 'ontime-types';
 import { CSSProperties, RefObject } from 'react';
 
 import { useAnimatedProgress } from '../../common/hooks/useAnimatedProgress';
-import { useExpectedStartData, useSelectedEventId, useTimer } from '../../common/hooks/useSocket';
+import { useExpectedStartData, useTimer } from '../../common/hooks/useSocket';
 import { alpha, cx } from '../../common/utils/styleUtils';
 import { formatDuration, formatTime, getExpectedTimesFromExtendedEvent } from '../../common/utils/time';
 import { useTranslation } from '../../translation/TranslationProvider';
@@ -169,8 +169,7 @@ function TimelineEntryStatus({
 /** Generates a block level progress bar */
 function ActiveBlock() {
   const { current, duration } = useTimer();
-  const eventId = useSelectedEventId();
+  const progress = useAnimatedProgress(current, duration);
-  const progress = useAnimatedProgress(current, duration, eventId);
   return (
     <div data-status='live' className={style.timelineBlock} style={{ '--progress': `${progress}%` } as CSSProperties} />
   );

apps/client/src/views/timer/Timer.tsx

@@ -195,7 +195,6 @@ function Timer({ customFields, projectData, isMirrored, settings, viewSettings,
           className={cx(['progress-container', !isPlaying && 'progress-container--paused'])}
           now={time.current}
           complete={totalTime}
-          eventId={eventNow?.id}
           normalColor={viewSettings.normalColor}
           warning={eventNow?.timeWarning}
           warningColor={viewSettings.warningColor}

apps/server/src/lib/time-core/timeCore.ts

@@ -1,5 +1,5 @@
 import { Day, Duration, Instant, TimeOfDay } from 'ontime-types';
-import { MILLIS_PER_MINUTE, dayInMs } from 'ontime-utils';
+import { MILLIS_PER_HOUR, MILLIS_PER_MINUTE, MILLIS_PER_SECOND, dayInMs } from 'ontime-utils';
 
 /** Returns the current instant */
 export function now(): Instant {
@@ -59,6 +59,10 @@ export function addDuration(instant: Instant, duration: Duration | Duration[]):
   return (instant + totalDuration) as Instant;
 }
 
+export function combineValues<T extends Duration | Day>(...duration: T[]): T {
+  return Array.isArray(duration) ? (duration.reduce<number>((total, current) => total + current, 0) as T) : duration;
+}
+
 /**
  * Calculates elapsed time on the clock from a starting time to the current time
  * Handles overnight crossing (when current < start, assumes we've crossed midnight)
@@ -80,3 +84,15 @@ export function daysSinceStart(startEpoch: Instant, currentEpoch: Instant): Day
 
   return (currentDaySerial - startDaySerial) as Day;
 }
+
+export const ZERO_DURATION = 0 as Duration;
+
+/**
+ * utility function to generate Instant times
+ */
+export function generateInstanceFromClock(hour: number, minutes: number, second: number, ms = 0) {
+  return toInstant(
+    (hour * MILLIS_PER_HOUR + minutes * MILLIS_PER_MINUTE + second * MILLIS_PER_SECOND + ms) as TimeOfDay,
+    now(),
+  );
+}

apps/server/src/services/__tests__/timerUtils.test.ts

@@ -1,7 +1,8 @@
-import { EndAction, Playback, TimeOfDay, TimeStrategy, TimerPhase, TimerType } from 'ontime-types';
+import { Duration, EndAction, Playback, TimeOfDay, TimeStrategy, TimerPhase, TimerType } from 'ontime-types';
 import { MILLIS_PER_HOUR, MILLIS_PER_MINUTE, MILLIS_PER_SECOND, dayInMs, millisToString } from 'ontime-utils';
 
-import type { RuntimeState } from '../../stores/runtimeState.js';
+import * as timeCore from '../../lib/time-core/timeCore.js';
+import type { InternalRuntimeState, RuntimeState } from '../../stores/runtimeState.js';
 import {
   findDayOffset,
   getCurrent,
@@ -19,48 +20,48 @@ const asTimeOfDay = (value: number): RuntimeState['clock'] => value as RuntimeSt
 describe('getElapsed()', () => {
   it('returns active elapsed time from startedAt without add-time adjustments', () => {
     const state = {
-      clock: 5 * MILLIS_PER_MINUTE,
+      _now: timeCore.generateInstanceFromClock(0, 5, 0),
       timer: {
         addedTime: -10 * MILLIS_PER_MINUTE,
         current: 15 * MILLIS_PER_MINUTE,
         duration: 20 * MILLIS_PER_MINUTE,
-        startedAt: 2 * MILLIS_PER_MINUTE,
+        startedAt: timeCore.generateInstanceFromClock(0, 2, 0),
       },
       _timer: {
         pausedAt: null,
         pausedDuration: 0,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     expect(getElapsed(state)).toBe(3 * MILLIS_PER_MINUTE);
   });
 
   it('subtracts accumulated pause time', () => {
     const state = {
-      clock: 10 * MILLIS_PER_MINUTE,
+      _now: timeCore.generateInstanceFromClock(0, 10, 0),
       timer: {
-        startedAt: 2 * MILLIS_PER_MINUTE,
+        startedAt: timeCore.generateInstanceFromClock(0, 2, 0),
       },
       _timer: {
         pausedAt: null,
         pausedDuration: 5 * MILLIS_PER_MINUTE,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     expect(getElapsed(state)).toBe(3 * MILLIS_PER_MINUTE);
   });
 
   it('uses the current pause start while paused', () => {
     const state = {
-      clock: 10 * MILLIS_PER_MINUTE,
+      _now: timeCore.generateInstanceFromClock(0, 10, 0),
       timer: {
-        startedAt: 2 * MILLIS_PER_MINUTE,
+        startedAt: timeCore.generateInstanceFromClock(0, 2, 0),
       },
       _timer: {
         pausedAt: 7 * MILLIS_PER_MINUTE,
         pausedDuration: 1 * MILLIS_PER_MINUTE,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     expect(getElapsed(state)).toBe(4 * MILLIS_PER_MINUTE);
   });
@@ -82,7 +83,7 @@ describe('getExpectedFinish()', () => {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
     const calculatedFinish = getExpectedFinish(state);
     expect(calculatedFinish).toBe(null);
   });
@@ -95,13 +96,13 @@ describe('getExpectedFinish()', () => {
       timer: {
         addedTime: 0,
         duration: 10,
-        startedAt: 10,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 10),
       },
       _timer: {
         pausedAt: null,
         hasFinished: true,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
     const calculatedFinish = getExpectedFinish(state);
     expect(calculatedFinish).toBe(20);
   });
@@ -114,13 +115,13 @@ describe('getExpectedFinish()', () => {
       timer: {
         addedTime: 0,
         duration: 10,
-        startedAt: 1,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 1),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
     const calculatedFinish = getExpectedFinish(state);
     expect(calculatedFinish).toBe(11);
   });
@@ -133,13 +134,13 @@ describe('getExpectedFinish()', () => {
       timer: {
         addedTime: 20,
         duration: 10,
-        startedAt: 1,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 1),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const calculatedFinish = getExpectedFinish(state);
     expect(calculatedFinish).toBe(31);
@@ -153,13 +154,13 @@ describe('getExpectedFinish()', () => {
       timer: {
         addedTime: -10,
         duration: 10,
-        startedAt: 1,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 1),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const calculatedFinish = getExpectedFinish(state);
     expect(calculatedFinish).toBe(1);
@@ -173,13 +174,13 @@ describe('getExpectedFinish()', () => {
       timer: {
         addedTime: -100,
         duration: 10,
-        startedAt: 1,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 1),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const calculatedFinish = getExpectedFinish(state);
     expect(calculatedFinish).toBe(1);
@@ -193,13 +194,13 @@ describe('getExpectedFinish()', () => {
       timer: {
         addedTime: 0,
         duration: 0,
-        startedAt: 1,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 1),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const calculatedFinish = getExpectedFinish(state);
     expect(calculatedFinish).toBe(1);
@@ -213,13 +214,13 @@ describe('getExpectedFinish()', () => {
       timer: {
         addedTime: 0,
         duration: dayInMs,
-        startedAt: 10,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 10),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const calculatedFinish = getExpectedFinish(state);
     expect(calculatedFinish).toBe(10);
@@ -234,13 +235,13 @@ describe('getExpectedFinish()', () => {
         timer: {
           addedTime: 10,
           duration: dayInMs,
-          startedAt: 10,
+          startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 10),
         },
         _timer: {
           pausedAt: null,
           hasFinished: false,
         },
-      } as RuntimeState;
+      } as InternalRuntimeState;
 
       const calculatedFinish = getExpectedFinish(state);
       expect(calculatedFinish).toBe(40);
@@ -253,7 +254,7 @@ describe('getExpectedFinish()', () => {
         },
         timer: {
           addedTime: 0,
-          startedAt: 79200000, // 22:00:00
+          startedAt: timeCore.generateInstanceFromClock(22, 0, 0),
         },
         _timer: {
           pausedAt: null,
@@ -263,7 +264,7 @@ describe('getExpectedFinish()', () => {
           actualStart: 79200000,
           plannedEnd: 600000,
         },
-      } as RuntimeState;
+      } as InternalRuntimeState;
 
       const calculatedFinish = getExpectedFinish(state);
       // expected finish is not a duration but a point in time
@@ -279,7 +280,7 @@ describe('getCurrent()', () => {
         timeEnd: 30,
         timerType: TimerType.CountDown,
       },
-      clock: 0,
+      _now: timeCore.generateInstanceFromClock(0, 0, 0),
       timer: {
         addedTime: 10,
         duration: 111, // <-- we take the duration value
@@ -289,7 +290,7 @@ describe('getCurrent()', () => {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const current = getCurrent(state);
     expect(current).toBe(111);
@@ -300,17 +301,17 @@ describe('getCurrent()', () => {
         timeEnd: 10,
         timerType: TimerType.CountDown,
       },
-      clock: 1,
+      _now: timeCore.generateInstanceFromClock(0, 0, 0, 1),
       timer: {
         addedTime: 0,
         duration: 10,
-        startedAt: 0,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const current = getCurrent(state);
     expect(current).toBe(9);
@@ -321,17 +322,17 @@ describe('getCurrent()', () => {
         timeEnd: 10,
         timerType: TimerType.CountDown,
       },
-      clock: 1,
+      _now: timeCore.generateInstanceFromClock(0, 0, 0, 1),
       timer: {
         addedTime: 10,
         duration: 10,
-        startedAt: 0,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const current = getCurrent(state);
     expect(current).toBe(19);
@@ -342,17 +343,17 @@ describe('getCurrent()', () => {
         timeEnd: 20,
         timerType: TimerType.CountDown,
       },
-      clock: 10,
+      _now: timeCore.generateInstanceFromClock(0, 0, 0, 10),
       timer: {
         addedTime: 0,
         duration: dayInMs + 10,
-        startedAt: 10,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 10),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const current = getCurrent(state);
     expect(current).toBe(dayInMs + 10);
@@ -363,17 +364,17 @@ describe('getCurrent()', () => {
         timeEnd: 20,
         timerType: TimerType.CountDown,
       },
-      clock: 5,
+      _now: timeCore.generateInstanceFromClock(0, 0, 0, 5),
       timer: {
         addedTime: 0,
         duration: dayInMs + 10,
-        startedAt: 10,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 10),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const current = getCurrent(state);
     expect(current).toBe(15);
@@ -384,17 +385,17 @@ describe('getCurrent()', () => {
         timeEnd: 20,
         timerType: TimerType.CountDown,
       },
-      clock: 5,
+      _now: timeCore.generateInstanceFromClock(0, 0, 0, 5),
       timer: {
         addedTime: 20,
         duration: dayInMs + 10,
-        startedAt: 10,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 10),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const current = getCurrent(state);
     expect(current).toBe(35);
@@ -407,7 +408,7 @@ describe('getCurrent()', () => {
           timeEnd: 100,
           countToEnd: true,
         },
-        clock: 30,
+        _now: timeCore.generateInstanceFromClock(0, 0, 0, 30),
         timer: {
           addedTime: 0,
           duration: 100,
@@ -420,7 +421,7 @@ describe('getCurrent()', () => {
           pausedAt: null,
           hasFinished: false,
         },
-      } as RuntimeState;
+      } as InternalRuntimeState;
 
       const current = getCurrent(state);
       expect(current).toBe(70);
@@ -432,11 +433,11 @@ describe('getCurrent()', () => {
           timeEnd: 100,
           countToEnd: true,
         },
-        clock: 30,
+        _now: timeCore.generateInstanceFromClock(0, 0, 0, 30),
         timer: {
           addedTime: 0,
           duration: 100,
-          startedAt: 10,
+          startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 10),
         },
         rundown: {
           plannedEnd: 100,
@@ -445,7 +446,7 @@ describe('getCurrent()', () => {
           pausedAt: null,
           hasFinished: false,
         },
-      } as RuntimeState;
+      } as InternalRuntimeState;
 
       const current = getCurrent(state);
       expect(current).toBe(70);
@@ -457,11 +458,11 @@ describe('getCurrent()', () => {
           timeEnd: 100,
           countToEnd: true,
         },
-        clock: 30,
+        _now: timeCore.generateInstanceFromClock(0, 0, 0, 30),
         timer: {
           addedTime: 7,
           duration: 100,
-          startedAt: 10,
+          startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 10),
         },
         rundown: {
           plannedEnd: 100,
@@ -470,7 +471,7 @@ describe('getCurrent()', () => {
           pausedAt: null,
           hasFinished: false,
         },
-      } as RuntimeState;
+      } as InternalRuntimeState;
 
       const current = getCurrent(state);
       expect(current).toBe(77);
@@ -483,11 +484,11 @@ describe('getCurrent()', () => {
           timeEnd: 600000, // 00:10:00
           countToEnd: true,
         },
-        clock: 79500000, // 22:05:00
+        _now: timeCore.generateInstanceFromClock(22, 5, 0),
         timer: {
           addedTime: 0,
           duration: Infinity, // not relevant,
-          startedAt: 79200000, // 22:00:00
+          startedAt: timeCore.generateInstanceFromClock(22, 0, 0),
         },
         rundown: {
           actualStart: 79200000,
@@ -497,7 +498,7 @@ describe('getCurrent()', () => {
           pausedAt: null,
           hasFinished: false,
         },
-      } as RuntimeState;
+      } as InternalRuntimeState;
 
       const current = getCurrent(state);
       expect(current).toBe(dayInMs - 79500000 + 600000);
@@ -505,7 +506,7 @@ describe('getCurrent()', () => {
 
     it('handles events that were started late', () => {
       const state = {
-        clock: 82000000, // 22:46:40 <--- starting 16 min after the scheduled end
+        _now: timeCore.generateInstanceFromClock(22, 46, 40), // 22:46:40 <--- starting 16 min after the scheduled end
         eventNow: {
           timeStart: 77400000, // 21:30:00
           timeEnd: 81000000, // 22:30:00
@@ -515,7 +516,7 @@ describe('getCurrent()', () => {
         timer: {
           addedTime: 0,
           duration: Infinity, // not relevant,
-          startedAt: 79200000, // 22:00:00
+          startedAt: timeCore.generateInstanceFromClock(22, 0, 0),
         },
         rundown: {
           actualStart: 82000000, // 22:46:40 <--- started now
@@ -525,7 +526,7 @@ describe('getCurrent()', () => {
           pausedAt: null,
           hasFinished: false,
         },
-      } as RuntimeState;
+      } as InternalRuntimeState;
 
       const current = getCurrent(state);
       expect(current).toBe(81000000 - 82000000); // <-- planned end - now
@@ -541,17 +542,17 @@ describe('getExpectedFinish() and getCurrentTime() combined', () => {
         timeEnd: 10,
         timerType: TimerType.CountDown,
       },
-      clock: 0,
+      _now: timeCore.generateInstanceFromClock(0, 0, 0),
       timer: {
         addedTime: 0,
         duration,
-        startedAt: 0,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const expectedFinish = getExpectedFinish(state);
     const current = getCurrent(state);
@@ -569,25 +570,25 @@ describe('getExpectedFinish() and getCurrentTime() combined', () => {
         timeEnd: 10,
         timerType: TimerType.CountDown,
       },
-      clock: 5,
+      _now: timeCore.generateInstanceFromClock(0, 0, 0, 5),
       timer: {
         addedTime: 3,
         duration,
-        startedAt: 0,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0),
       },
       _timer: {
         pausedAt: null,
         hasFinished: false,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const expectedFinish = getExpectedFinish(state);
     const current = getCurrent(state);
 
     const elapsed = duration - current;
     expect(expectedFinish).toBe(13);
-    expect(elapsed).toBe(2);
     expect(current).toBe(8);
+    expect(elapsed).toBe(2);
   });
 });
 
@@ -871,7 +872,7 @@ describe('getRuntimeOffset()', () => {
         dayOffset: 0,
       },
       timer: {
-        startedAt: 150,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 150),
         addedTime: 0,
         current: 0,
       },
@@ -883,9 +884,9 @@ describe('getRuntimeOffset()', () => {
         plannedStart: 100,
         currentDay: 0,
       },
-      clock: 150,
+      _now: timeCore.generateInstanceFromClock(0, 0, 0, 150),
       _startDayOffset: 0,
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const { absolute } = getRuntimeOffset(state);
     expect(absolute).toBe(50);
@@ -899,7 +900,7 @@ describe('getRuntimeOffset()', () => {
         dayOffset: 0,
       },
       timer: {
-        startedAt: 150, // we started 50ms delayed
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 150), // we started 50ms delayed
         addedTime: 10, // we compensated with 10ms
         current: 10, // we are 10ms into the timer
       },
@@ -912,7 +913,7 @@ describe('getRuntimeOffset()', () => {
         currentDay: 0,
       },
       _startDayOffset: 0,
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const { absolute } = getRuntimeOffset(state);
     expect(absolute).toBe(60);
@@ -927,7 +928,7 @@ describe('getRuntimeOffset()', () => {
         dayOffset: 0,
       },
       timer: {
-        startedAt: 100, // we started ontime
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 100), // we started ontime
         current: -10, // we are 10 seconds over
         addedTime: 0, // we have not compensated with added time
       },
@@ -940,7 +941,7 @@ describe('getRuntimeOffset()', () => {
         currentDay: 0,
       },
       _startDayOffset: 0,
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const { absolute } = getRuntimeOffset(state);
     expect(absolute).toBe(10);
@@ -954,9 +955,9 @@ describe('getRuntimeOffset()', () => {
         timeEnd: 150,
         dayOffset: 0,
       },
-      clock: 150,
+      _now: timeCore.generateInstanceFromClock(0, 0, 0, 150),
       timer: {
-        startedAt: 100, // started on time
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 100), // started on time
         current: 25, // are 25ms into it
         addedTime: 0,
       },
@@ -969,7 +970,7 @@ describe('getRuntimeOffset()', () => {
         currentDay: 0,
       },
       _startDayOffset: 0,
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const { absolute } = getRuntimeOffset(state);
     expect(absolute).toBe(25);
@@ -977,7 +978,7 @@ describe('getRuntimeOffset()', () => {
 
   it('offset doesnt exist if we havent started', () => {
     const state = {
-      clock: 78480789,
+      _now: timeCore.generateInstanceFromClock(22, 48, 0), // 78480789
       eventNow: {
         id: 'd6a2ce',
         timeStart: 77400000,
@@ -1011,7 +1012,7 @@ describe('getRuntimeOffset()', () => {
       },
       _startDayOffset: 0,
       _timer: { pausedAt: null },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const { absolute } = getRuntimeOffset(state);
     expect(absolute).toBe(0);
@@ -1019,7 +1020,7 @@ describe('getRuntimeOffset()', () => {
 
   it('with time-to-end, offsets dont exist if we are not in overtime', () => {
     const state = {
-      clock: 80000000, // 22:13:20
+      _now: timeCore.generateInstanceFromClock(22, 13, 20),
       eventNow: {
         id: 'd6a2ce',
         type: 'event',
@@ -1063,11 +1064,11 @@ describe('getRuntimeOffset()', () => {
         expectedFinish: 81600000,
         playback: Playback.Play,
         secondaryTimer: null,
-        startedAt: 78000000,
+        startedAt: timeCore.generateInstanceFromClock(21, 40, 0),
       },
       _startDayOffset: 0,
       _timer: { pausedAt: null },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const { absolute } = getRuntimeOffset(state);
     expect(absolute).toBe(0);
@@ -1075,7 +1076,7 @@ describe('getRuntimeOffset()', () => {
 
   it('with time-to-end, offset is the overtime', () => {
     const state = {
-      clock: 82000000, // 22:46:40
+      _now: timeCore.generateInstanceFromClock(22, 46, 40),
       eventNow: {
         id: 'd6a2ce',
         type: 'event',
@@ -1119,11 +1120,11 @@ describe('getRuntimeOffset()', () => {
         expectedFinish: 81600000,
         playback: Playback.Play,
         secondaryTimer: null,
-        startedAt: 78000000,
+        startedAt: timeCore.generateInstanceFromClock(21, 40, 0),
       },
       _startDayOffset: 0,
       _timer: { pausedAt: null },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const { absolute } = getRuntimeOffset(state);
     expect(absolute).toBe(400000 - 200000); // <--- offset is always the overtime + added time
@@ -1131,7 +1132,7 @@ describe('getRuntimeOffset()', () => {
 
   it('handles time-to-end started after the end time', () => {
     const state = {
-      clock: 82000000, // 22:46:40 <--- starting 16m 40s after the scheduled end
+      _now: timeCore.generateInstanceFromClock(22, 46, 40), // 22:46:40 <--- starting 16m 40s after the scheduled end
       eventNow: {
         id: 'd6a2ce',
         timeStart: 77400000, // 21:30:00
@@ -1164,14 +1165,14 @@ describe('getRuntimeOffset()', () => {
         expectedFinish: 82000000 + 3600000, // <--- now + duration
         playback: Playback.Play,
         secondaryTimer: null,
-        startedAt: 82000000, // <--- started now
+        startedAt: timeCore.generateInstanceFromClock(22, 46, 40),
       },
       _startDayOffset: 0,
       _timer: { pausedAt: null },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const updateCurrent = getCurrent(state);
-    state.timer.current = updateCurrent;
+    state.timer.current = updateCurrent as Duration;
     const { absolute } = getRuntimeOffset(state);
     expect(millisToString(absolute)).toBe('00:16:40');
     expect(absolute).toBe(82000000 - 81000000); // <-- now - planned end
@@ -1187,7 +1188,7 @@ describe('getRuntimeOffset() relative', () => {
         dayOffset: 0,
       },
       timer: {
-        startedAt: 150,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 150),
         addedTime: 0,
         current: 0,
       },
@@ -1200,7 +1201,7 @@ describe('getRuntimeOffset() relative', () => {
         currentDay: 0,
       },
       _startDayOffset: 0,
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const { absolute, relative } = getRuntimeOffset(state);
     expect(absolute).toBe(0);
@@ -1214,7 +1215,7 @@ describe('getRuntimeOffset() relative', () => {
         dayOffset: 0,
       },
       timer: {
-        startedAt: 150,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 150),
         addedTime: 0,
         current: 0,
       },
@@ -1227,7 +1228,7 @@ describe('getRuntimeOffset() relative', () => {
         currentDay: 0,
       },
       _startDayOffset: 0,
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const { absolute, relative } = getRuntimeOffset(state);
     expect(absolute).toBe(50);
@@ -1241,7 +1242,7 @@ describe('getRuntimeOffset() relative', () => {
         dayOffset: 0,
       },
       timer: {
-        startedAt: 100,
+        startedAt: timeCore.generateInstanceFromClock(0, 0, 0, 100),
         addedTime: 0,
         current: 0,
       },
@@ -1254,7 +1255,7 @@ describe('getRuntimeOffset() relative', () => {
         currentDay: 0,
       },
       _startDayOffset: 0,
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const { absolute, relative } = getRuntimeOffset(state);
     expect(absolute).toBe(-50);
@@ -1276,7 +1277,7 @@ describe('getTimerPhase()', () => {
         secondaryTimer: null,
         startedAt: null,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const phase = getTimerPhase(state);
     expect(phase).toBe(TimerPhase.None);
@@ -1294,7 +1295,7 @@ describe('getTimerPhase()', () => {
         timeDanger: 100,
         timeWarning: 200,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const phase = getTimerPhase(state);
     expect(phase).toBe(TimerPhase.Overtime);
@@ -1312,7 +1313,7 @@ describe('getTimerPhase()', () => {
         timeDanger: 100,
         timeWarning: 200,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const phase = getTimerPhase(state);
     expect(phase).toBe(TimerPhase.Danger);
@@ -1330,7 +1331,7 @@ describe('getTimerPhase()', () => {
         timeDanger: 100,
         timeWarning: 200,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const phase = getTimerPhase(state);
     expect(phase).toBe(TimerPhase.Warning);
@@ -1348,7 +1349,7 @@ describe('getTimerPhase()', () => {
         timeDanger: 100,
         timeWarning: 200,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const phase = getTimerPhase(state);
     expect(phase).toBe(TimerPhase.Default);
@@ -1356,7 +1357,7 @@ describe('getTimerPhase()', () => {
 
   it('#1042 identifies waiting to roll', () => {
     const state = {
-      clock: 55691050,
+      _now: timeCore.generateInstanceFromClock(16, 28, 11), //55691050
       eventNow: null,
       eventNext: null,
       rundown: {
@@ -1382,13 +1383,13 @@ describe('getTimerPhase()', () => {
         startedAt: null,
       },
       _timer: {
-        forceFinish: null,
+        forceFinish: false,
         pausedAt: null,
       },
       _rundown: {
         totalDelay: 0,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const phase = getTimerPhase(state);
     expect(phase).toBe(TimerPhase.Pending);
@@ -1396,7 +1397,7 @@ describe('getTimerPhase()', () => {
 
   it('#1042 identifies waiting to roll', () => {
     const state = {
-      clock: 55691050,
+      _now: timeCore.generateInstanceFromClock(16, 28, 11), //55691050
       eventNow: null,
       eventNext: null,
       rundown: {
@@ -1422,13 +1423,13 @@ describe('getTimerPhase()', () => {
         startedAt: null,
       },
       _timer: {
-        forceFinish: null,
+        forceFinish: false,
         pausedAt: null,
       },
       _rundown: {
         totalDelay: 0,
       },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const phase = getTimerPhase(state);
     expect(phase).toBe(TimerPhase.Pending);

apps/server/src/services/rollUtils.ts

@@ -5,6 +5,8 @@ import { RundownMetadata } from '../api-data/rundown/rundown.types.js';
 import { getTimedIndexFromPlayableIndex } from '../api-data/rundown/rundown.utils.js';
 import { normaliseEndTime } from './timerUtils.js';
 
+// import * as timeCore from '../lib/time-core/timeCore.js';
+
 /**
  * Finds current event in a rolling rundown
  */

apps/server/src/services/runtime-service/runtime.service.ts

@@ -760,16 +760,17 @@ function broadcastResult(_target: any, _propertyKey: string, descriptor: Propert
 
     // save the restore state
     if (hasImmediateChanges) {
+      const internalState = runtimeState.getInternalState();
       restoreService
         .save({
           playback: state.timer.playback,
           selectedEventId: state.eventNow?.id ?? null,
           startedAt: state.timer.startedAt,
           addedTime: state.timer.addedTime,
-          pausedAt: state._timer.pausedAt,
+          pausedAt: internalState._timer.pausedAt,
-          pausedDuration: state._timer.pausedDuration,
+          pausedDuration: internalState._timer.pausedDuration,
           firstStart: state.rundown.actualStart,
-          startEpoch: state._startEpoch,
+          startEpoch: internalState._startEpoch,
           currentDay: state.rundown.currentDay,
         })
         .catch((_e) => {

apps/server/src/services/timerUtils.ts

@@ -1,7 +1,9 @@
-import { Day, MaybeNumber, TimeOfDay, TimerPhase } from 'ontime-types';
+import { Day, Duration, Maybe, TimeOfDay, TimerPhase } from 'ontime-types';
 import { MILLIS_PER_HOUR, checkIsNow, dayInMs, isPlaybackActive } from 'ontime-utils';
 
-import type { RuntimeState } from '../stores/runtimeState.js';
+import * as timeCore from '../lib/time-core/timeCore.js';
+import { ZERO_DURATION } from '../lib/time-core/timeCore.js';
+import type { InternalRuntimeState, RuntimeState } from '../stores/runtimeState.js';
 
 /**
  * handle events that span over midnight
@@ -20,48 +22,46 @@ export function hasCrossedMidnight(previous: TimeOfDay, current: TimeOfDay): boo
 
 /**
  * Calculates expected finish time of a running timer
- * @param {RuntimeState} state runtime state
+ * @param {InternalRuntimeState} state runtime state
  * @returns {number | null} new current time or null if nothing is running
  */
-export function getExpectedFinish(state: RuntimeState): MaybeNumber {
+export function getExpectedFinish(state: InternalRuntimeState): Maybe<TimeOfDay> {
   const { startedAt, duration, addedTime } = state.timer;
-
   if (state.eventNow === null) {
     return null;
   }
 
   const { countToEnd, timeEnd } = state.eventNow;
   const { pausedAt } = state._timer;
-  const { clock } = state;
+  const { _now } = state;
 
   if (startedAt === null) {
     return null;
   }
 
-  const pausedTime = pausedAt != null ? clock - pausedAt : 0;
+  const pausedTime = pausedAt !== null ? timeCore.toTimeOfDay(_now) - pausedAt : 0;
-
   if (countToEnd) {
-    return timeEnd + addedTime + pausedTime;
+    return (timeEnd + addedTime + pausedTime) as TimeOfDay;
   }
 
   // handle events that finish the day after
-  // eslint-disable-next-line @typescript-eslint/no-non-null-assertion -- duration exists if ther eis a timer
+  // eslint-disable-next-line @typescript-eslint/no-non-null-assertion -- duration exists if there is a timer
-  const expectedFinish = startedAt + duration! + addedTime + pausedTime;
+  const expectedFinish = timeCore.toTimeOfDay(startedAt) + duration! + addedTime + pausedTime;
+
   if (expectedFinish > dayInMs) {
-    return expectedFinish - dayInMs;
+    return (expectedFinish - dayInMs) as TimeOfDay;
   }
 
   // an event cannot finish before it started (user added too much negative time)
-  return Math.max(expectedFinish, startedAt);
+  return Math.max(expectedFinish, timeCore.toTimeOfDay(startedAt)) as TimeOfDay;
 }
 
 /**
  * Calculates running countdown
- * @param {RuntimeState} state runtime state
+ * @param {InternalRuntimeState} state runtime state
  * @returns {number} current time for timer
  */
-
+export function getCurrent(state: InternalRuntimeState): Duration {
-export function getCurrent(state: RuntimeState): number {
   // eslint-disable-next-line no-unused-labels -- dev code path
   DEV: {
     if (state.eventNow === null || state.timer.duration === null) {
@@ -71,12 +71,12 @@ export function getCurrent(state: RuntimeState): number {
   const { startedAt, duration, addedTime } = state.timer;
   const { countToEnd, timeStart, timeEnd } = state.eventNow;
   const { pausedAt } = state._timer;
-  const { clock } = state;
+  const { _now } = state;
 
   if (countToEnd) {
     const isEventOverMidnight = timeStart > timeEnd;
     const correctDay = isEventOverMidnight ? dayInMs : 0;
-    return correctDay - clock + timeEnd + addedTime;
+    return (correctDay - timeCore.toTimeOfDay(_now) + timeEnd + addedTime) as Duration;
   }
 
   if (startedAt === null) {
@@ -84,19 +84,19 @@ export function getCurrent(state: RuntimeState): number {
   }
 
   if (pausedAt != null) {
-    return startedAt + duration + addedTime - pausedAt;
+    return (timeCore.toTimeOfDay(startedAt) + duration + addedTime - pausedAt) as Duration;
   }
 
-  const hasPassedMidnight = startedAt > clock;
+  const hasPassedMidnight = timeCore.toTimeOfDay(startedAt) > timeCore.toTimeOfDay(_now);
   const correctDay = hasPassedMidnight ? dayInMs : 0;
-  return startedAt + duration + addedTime - clock - correctDay;
+  return (timeCore.toTimeOfDay(startedAt) + duration + addedTime - timeCore.toTimeOfDay(_now) - correctDay) as Duration;
 }
 
 /**
  * Calculates active time elapsed since the timer started.
  */
-export function getElapsed(state: RuntimeState): MaybeNumber {
+export function getElapsed(state: InternalRuntimeState): Maybe<Duration> {
-  const { clock } = state;
+  const { _now } = state;
   const { startedAt } = state.timer;
   const { pausedAt, pausedDuration } = state._timer;
 
@@ -104,11 +104,11 @@ export function getElapsed(state: RuntimeState): MaybeNumber {
     return null;
   }
 
-  const referenceClock = pausedAt ?? clock;
+  const referenceClock = pausedAt ?? timeCore.toTimeOfDay(_now);
-  const elapsedSinceStart = getTimeSinceStart(referenceClock, startedAt);
+  const elapsedSinceStart = getTimeSinceStart(referenceClock, timeCore.toTimeOfDay(startedAt));
   const activeElapsed = elapsedSinceStart - pausedDuration;
 
-  return Math.max(0, activeElapsed);
+  return Math.max(0, activeElapsed) as Duration;
 }
 
 function getTimeSinceStart(clock: TimeOfDay, startedAt: number): number {
@@ -127,7 +127,7 @@ function getTimeSinceStart(clock: TimeOfDay, startedAt: number): number {
  * @returns {boolean}
  */
 export function skippedOutOfEvent(state: RuntimeState, previousTime: number, skipLimit: number): boolean {
-  // we cant have skipped if we havent started
+  // we cant have skipped if we haven't started
   if (state.timer.expectedFinish === null || state.timer.startedAt === null) {
     return false;
   }
@@ -151,12 +151,12 @@ export function skippedOutOfEvent(state: RuntimeState, previousTime: number, ski
  * Positive offset is over time / behind schedule
  * Negative offset is under time / ahead of schedule
  */
-export function getRuntimeOffset(state: RuntimeState): { absolute: number; relative: number } {
+export function getRuntimeOffset(state: InternalRuntimeState): { absolute: Duration; relative: Duration } {
-  const { eventNow, clock, _startDayOffset } = state;
+  const { eventNow, _now, _startDayOffset } = state;
   const { addedTime, current, startedAt } = state.timer;
   // nothing to calculate if there are no loaded events or if we havent started
   if (eventNow === null || startedAt === null || _startDayOffset === null) {
-    return { absolute: 0, relative: 0 };
+    return { absolute: ZERO_DURATION, relative: ZERO_DURATION };
   }
 
   const { countToEnd, timeStart, dayOffset } = eventNow;
@@ -171,20 +171,23 @@ export function getRuntimeOffset(state: RuntimeState): { absolute: number; relat
   }
 
   // difference between planned event start and actual event start (will be positive if we started behind)
-  const eventStartOffset = startedAt + _startDayOffset * dayInMs - (timeStart + dayOffset * dayInMs);
+  const eventStartOffset =
+    timeCore.toTimeOfDay(startedAt) + _startDayOffset * dayInMs - (timeStart + dayOffset * dayInMs);
 
   // how long has the event been running over (is a negative number when in over timer so inverted before adding to offset)
   const overtime = Math.abs(Math.min(current, 0));
 
   // time the playback was paused, the different from now to when we paused is added to the offset TODO: brakes when crossing midnight
-  const pausedTime = state._timer.pausedAt === null ? 0 : clock - state._timer.pausedAt;
+  const pausedTime = state._timer.pausedAt === null ? 0 : timeCore.toTimeOfDay(_now) - state._timer.pausedAt;
 
   // absolute offset is difference between schedule and playback time
   // in case of count to end, the absolute offset is overtime and added time
-  const absolute = countToEnd ? overtime + addedTime : eventStartOffset + overtime + pausedTime + addedTime;
+  const absolute = (
+    countToEnd ? overtime + addedTime : eventStartOffset + overtime + pausedTime + addedTime
+  ) as Duration;
 
   // the relative offset is the same as the absolute but adjusted relative to the actual start time
-  const relative = absolute + plannedStart - actualStart - _startDayOffset * dayInMs;
+  const relative = (absolute + plannedStart - actualStart - _startDayOffset * dayInMs) as Duration;
 
   return { absolute, relative };
 }
@@ -193,7 +196,7 @@ export function getRuntimeOffset(state: RuntimeState): { absolute: number; relat
  * Checks running timer to see which phase it currently is in
  * @param state
  */
-export function getTimerPhase(state: RuntimeState): TimerPhase {
+export function getTimerPhase(state: InternalRuntimeState): TimerPhase {
   if (!isPlaybackActive(state.timer.playback)) {
     return TimerPhase.None;
   }
@@ -223,7 +226,7 @@ export function getTimerPhase(state: RuntimeState): TimerPhase {
 
 /**
  * Finds the day offset relative to an event start
- * used byt the runtimeState on first start to get correct offsets
+ * used by the RuntimeState on first start to get correct offsets
  */
 export function findDayOffset(plannedStart: number, clock: number): Day {
   const distance = clock - plannedStart;

apps/server/src/stores/__mocks__/runtimeState.mocks.ts

@@ -1,33 +1,12 @@
-import { OffsetMode, Playback, type TimeOfDay, TimerPhase } from 'ontime-types';
+import { Day, type Duration, type Instant, OffsetMode, Playback, TimeOfDay, TimerPhase } from 'ontime-types';
 import { deepmerge } from 'ontime-utils';
 
-import type { RuntimeState } from '../runtimeState.js';
+import { ZERO_DURATION } from '../../lib/time-core/timeCore.js';
+import type { InternalRuntimeState, RuntimeState } from '../runtimeState.js';
 
-const baseState: RuntimeState = {
+export const runtimePlaceholder = {
-  clock: 0 as TimeOfDay,
-  eventNow: null,
-  eventNext: null,
-  eventFlag: null,
-  groupNow: null,
-  rundown: {
-    selectedEventIndex: null,
-    numEvents: 0,
-    plannedStart: 0,
-    plannedEnd: 0,
-    actualStart: null,
-    actualGroupStart: null,
-    currentDay: 0,
-  },
-  offset: {
-    absolute: 0,
-    relative: 0,
-    mode: OffsetMode.Absolute,
-    expectedRundownEnd: null,
-    expectedGroupEnd: null,
-    expectedFlagStart: null,
-  },
   timer: {
-    addedTime: 0,
+    addedTime: ZERO_DURATION,
     current: null,
     duration: null,
     elapsed: null,
@@ -37,10 +16,43 @@ const baseState: RuntimeState = {
     secondaryTimer: null,
     startedAt: null,
   },
+  offset: {
+    absolute: ZERO_DURATION,
+    relative: ZERO_DURATION,
+    mode: OffsetMode.Absolute,
+    expectedGroupEnd: null,
+    expectedRundownEnd: null,
+    expectedFlagStart: null,
+  },
+  rundown: {
+    selectedEventIndex: null,
+    numEvents: 0,
+    plannedStart: 0 as TimeOfDay,
+    plannedEnd: 0 as TimeOfDay,
+    actualStart: null,
+    actualGroupStart: null,
+
+    currentDay: 0 as Day,
+  },
+} as Readonly<InternalRuntimeState>;
+
+const baseState: InternalRuntimeState = {
+  _now: 0 as Instant,
+  eventNow: null,
+  eventNext: null,
+  eventFlag: null,
+  groupNow: null,
+  rundown: {
+    ...runtimePlaceholder.rundown,
+  },
+  offset: {
+    ...runtimePlaceholder.offset,
+  },
+  timer: { ...runtimePlaceholder.timer },
   _timer: {
-    forceFinish: null,
+    forceFinish: false,
     pausedAt: null,
-    pausedDuration: 0,
+    pausedDuration: 0 as Duration,
     secondaryTarget: null,
     hasFinished: false,
   },

apps/server/src/stores/__tests__/runtimeState.test.ts

@@ -6,9 +6,10 @@ import { rundownCache } from '../../api-data/rundown/rundown.dao.js';
 import { initRundown } from '../../api-data/rundown/rundown.service.js';
 import { RundownMetadata } from '../../api-data/rundown/rundown.types.js';
 import {
-  type RuntimeState,
+  type InternalRuntimeState,
   addTime,
   clearState,
+  getInternalState,
   getState,
   load,
   loadGroupFlagAndEnd,
@@ -32,7 +33,7 @@ const mockEvent = {
 } as PlayableEvent;
 
 const mockState = {
-  clock: 666,
+  _now: 666,
   eventNow: null,
   eventNext: null,
   rundown: {
@@ -53,7 +54,7 @@ const mockState = {
     pausedAt: null,
     hasFinished: false,
   },
-} as RuntimeState;
+} as InternalRuntimeState;
 
 vi.mock('../../classes/data-provider/DataProvider.js', () => {
   return {
@@ -108,34 +109,34 @@ describe('mutation on runtimeState', () => {
 
       const { metadata, rundown } = rundownCache.get();
       load(mockEvent, rundown, metadata);
-      let newState = getState();
+      let newState = getInternalState();
       expect(newState.eventNow?.id).toBe(mockEvent.id);
       expect(newState.eventNext?.id).toBe('event2');
       expect(newState.timer.playback).toBe(Playback.Armed);
-      expect(newState.clock).not.toBe(666);
+      expect(getState().clock).not.toBe(666);
       expect(newState.groupNow).toBeNull();
 
       // 2. Start event
       vi.setSystemTime('jan 1 00:02');
       let success = start();
-      newState = getState();
+      newState = getInternalState();
       expect(success).toBe(true);
       expect(newState.timer).toMatchObject({
         playback: Playback.Play,
       });
-      expect(newState.rundown.actualStart).toBe(newState.clock);
+      expect(newState.rundown.actualStart).toBe(getState().clock);
 
       // 3. Pause event
       vi.setSystemTime('jan 1 00:03');
       success = pause();
-      newState = getState();
+      newState = getInternalState();
       expect(success).toBe(true);
-      expect(newState.clock).not.toBe(666);
+      expect(getState().clock).not.toBe(666);
       expect(newState.timer).toMatchObject({
         playback: Playback.Pause,
         addedTime: 0,
       });
-      expect(newState._timer.pausedAt).toEqual(newState.clock);
+      expect(newState._timer.pausedAt).toEqual(getState().clock);
 
       success = pause();
       expect(success).toBe(false);
@@ -143,7 +144,7 @@ describe('mutation on runtimeState', () => {
       // 4. Restart event
       vi.setSystemTime('jan 1 00:04');
       success = start();
-      newState = getState();
+      newState = getInternalState();
       expect(success).toBe(true);
       expect(newState.timer).toMatchObject({
         playback: Playback.Play,
@@ -163,7 +164,7 @@ describe('mutation on runtimeState', () => {
       // 5. Stop event
       vi.setSystemTime('jan 1 00:05');
       success = stop();
-      newState = getState();
+      newState = getInternalState();
       expect(success).toBe(true);
       expect(newState.eventNow).toBe(null);
       expect(newState.timer).toMatchObject({
@@ -825,7 +826,7 @@ describe('roll mode', () => {
     test('pending event', () => {
       const { rundown, metadata } = rundownCache.get();
       const { eventId, didStart } = roll(rundown, metadata);
-      const state = getState();
+      const state = getInternalState();
 
       expect(eventId).toBe('1');
       expect(didStart).toBe(false);
@@ -944,7 +945,7 @@ describe('loadGroupFlagAndEnd()', () => {
       groupNow: null,
       eventNow: rundown.entries[11],
       rundown: { actualGroupStart: null },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const metadata = { playableEventOrder: ['0', '11', '3'], flags: ['1'] } as RundownMetadata;
 
@@ -972,7 +973,7 @@ describe('loadGroupFlagAndEnd()', () => {
       groupNow: rundown.entries[1],
       eventNow: rundown.entries[22],
       rundown: { actualGroupStart: null },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const metadata = { playableEventOrder: ['0', '11', '22'], flags: ['1'] } as RundownMetadata;
 
@@ -1000,7 +1001,7 @@ describe('loadGroupFlagAndEnd()', () => {
       groupNow: rundown.entries[1],
       eventNow: rundown.entries[0],
       rundown: { actualGroupStart: null },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const metadata = { playableEventOrder: ['0', '11', '22'], flags: ['1'] } as RundownMetadata;
 
@@ -1025,7 +1026,7 @@ describe('loadGroupFlagAndEnd()', () => {
       groupNow: null,
       eventNow: rundown.entries[0],
       rundown: { actualGroupStart: null },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const metadata = { playableEventOrder: ['0', '1'], flags: ['1'] } as RundownMetadata;
 
@@ -1087,7 +1088,7 @@ describe('loadGroupFlagAndEnd()', () => {
       groupNow: null,
       eventNow: rundown.entries[0],
       rundown: { actualGroupStart: null },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const metadata = { playableEventOrder: ['0', '1', '2', '3'], flags: ['3'] } as RundownMetadata;
 
@@ -1169,7 +1170,7 @@ describe('loadGroupFlagAndEnd()', () => {
       groupNow: null,
       eventNow: rundown.entries[0],
       rundown: { actualGroupStart: null },
-    } as RuntimeState;
+    } as InternalRuntimeState;
 
     const metadata = { playableEventOrder: ['0', '1', '2', '3'], flags: ['3'] } as RundownMetadata;
 

apps/server/src/stores/runtimeState.ts

@@ -17,7 +17,6 @@ import {
   TimerPhase,
   TimerState,
   isOntimeEvent,
-  runtimeStorePlaceholder,
 } from 'ontime-types';
 import {
   calculateDuration,
@@ -44,14 +43,18 @@ import {
   hasCrossedMidnight,
 } from '../services/timerUtils.js';
 import { timerConfig } from '../setup/config.js';
+import { runtimePlaceholder } from './__mocks__/runtimeState.mocks.js';
 
 type ExpectedMetadata = {
   event: OntimeEvent;
-  accumulatedGap: number;
+  accumulatedGap: Duration;
   isLinkedToLoaded: boolean;
 } | null;
 
 export type RuntimeState = {
+  /**
+   * @deprecated we want to phase out the 24h clock
+   */
   clock: TimeOfDay;
   groupNow: OntimeGroup | null;
   eventNow: PlayableEvent | null;
@@ -61,36 +64,72 @@ export type RuntimeState = {
   timer: TimerState;
   rundown: RundownState;
   // private properties of the timer calculations
+};
+
+export type InternalRuntimeState = Omit<RuntimeState, 'clock' | 'timer' | 'offset' | 'rundown'> & {
+  timer: {
+    addedTime: Duration;
+    current: Maybe<Duration>;
+    duration: Maybe<Duration>;
+    elapsed: Maybe<Duration>;
+    expectedFinish: Maybe<TimeOfDay>;
+    phase: TimerPhase;
+    playback: Playback;
+    secondaryTimer: Maybe<Duration>;
+    startedAt: Maybe<Instant>;
+  };
+  offset: {
+    absolute: Duration;
+    relative: Duration;
+    mode: OffsetMode;
+    expectedGroupEnd: Maybe<TimeOfDay>;
+    expectedRundownEnd: Maybe<TimeOfDay>;
+    expectedFlagStart: Maybe<TimeOfDay>;
+  };
+  rundown: {
+    selectedEventIndex: Maybe<number>;
+    numEvents: number;
+    plannedStart: Maybe<TimeOfDay>;
+    plannedEnd: Maybe<TimeOfDay>;
+    actualStart: Maybe<TimeOfDay>;
+    currentDay: Maybe<Day>;
+    actualGroupStart: Maybe<TimeOfDay>;
+  };
+  _now: Instant;
   _timer: {
-    forceFinish: Maybe<TimeOfDay>; // whether we should declare an event as finished, will contain the finish time
+    forceFinish: boolean; // whether we should declare an event as finished, will contain the finish time
     pausedAt: Maybe<TimeOfDay>;
-    pausedDuration: number;
+    pausedDuration: Duration;
     secondaryTarget: Maybe<TimeOfDay>;
     hasFinished: boolean;
   };
   _rundown: {
     totalDelay: number; // this value comes from rundown service
   };
+  _startDayOffset: Maybe<Day>;
+  _startEpoch: Maybe<Instant>;
   _group: ExpectedMetadata;
   _flag: ExpectedMetadata;
   _end: ExpectedMetadata;
-  _startEpoch: Maybe<Instant>;
-  _startDayOffset: Maybe<Day>;
 };
 
-const runtimeState: RuntimeState = {
+const runtimeState: InternalRuntimeState = {
-  clock: timeCore.timeOfDayNow(),
+  _now: timeCore.now(),
   groupNow: null,
   eventNow: null,
   eventNext: null,
   eventFlag: null,
-  offset: { ...runtimeStorePlaceholder.offset },
+  offset: { ...runtimePlaceholder.offset },
-  timer: { ...runtimeStorePlaceholder.timer },
+  timer: {
-  rundown: { ...runtimeStorePlaceholder.rundown },
+    ...runtimePlaceholder.timer,
+  },
+  rundown: {
+    ...runtimePlaceholder.rundown,
+  },
   _timer: {
-    forceFinish: null,
+    forceFinish: false,
     pausedAt: null,
-    pausedDuration: 0,
+    pausedDuration: 0 as Duration,
     secondaryTarget: null,
     hasFinished: false,
   },
@@ -104,19 +143,32 @@ const runtimeState: RuntimeState = {
   _startDayOffset: null,
 };
 
+export function getInternalState(): Readonly<InternalRuntimeState> {
+  return runtimeState;
+}
+
 export function getState(): Readonly<RuntimeState> {
   // create a shallow copy of the state
   return {
     ...runtimeState,
+    clock: timeCore.toTimeOfDay(runtimeState._now),
     eventNow: runtimeState.eventNow ? { ...runtimeState.eventNow } : null,
     eventNext: runtimeState.eventNext ? { ...runtimeState.eventNext } : null,
     eventFlag: runtimeState.eventFlag ? { ...runtimeState.eventFlag } : null,
     groupNow: runtimeState.groupNow ? { ...runtimeState.groupNow } : null,
     offset: { ...runtimeState.offset },
     rundown: { ...runtimeState.rundown },
-    timer: { ...runtimeState.timer },
+    timer: {
-    _timer: { ...runtimeState._timer },
+      addedTime: runtimeState.timer.addedTime,
-    _rundown: { ...runtimeState._rundown },
+      current: runtimeState.timer.current,
+      duration: runtimeState.timer.duration,
+      elapsed: runtimeState.timer.elapsed,
+      expectedFinish: runtimeState.timer.expectedFinish,
+      phase: runtimeState.timer.phase,
+      playback: runtimeState.timer.playback,
+      secondaryTimer: runtimeState.timer.secondaryTimer,
+      startedAt: runtimeState.timer.startedAt ? timeCore.toTimeOfDay(runtimeState.timer.startedAt) : null,
+    },
   };
 }
 
@@ -127,22 +179,18 @@ export function clearEventData() {
   runtimeState.eventNow = null;
   runtimeState.eventNext = null;
 
-  runtimeState.offset.absolute = 0;
+  runtimeState.offset = { ...runtimePlaceholder.offset };
-  runtimeState.offset.relative = 0;
-  runtimeState.offset.expectedFlagStart = null;
-  runtimeState.offset.expectedGroupEnd = null;
-  runtimeState.offset.expectedRundownEnd = null;
 
   runtimeState.rundown.selectedEventIndex = null;
 
   runtimeState.timer.playback = Playback.Stop;
-  runtimeState.clock = timeCore.timeOfDayNow();
+  runtimeState._now = timeCore.now();
-  runtimeState.timer = { ...runtimeStorePlaceholder.timer };
+  runtimeState.timer = { ...runtimePlaceholder.timer };
 
   // when clearing, we maintain the total delay from the rundown
-  runtimeState._timer.forceFinish = null;
+  runtimeState._timer.forceFinish = false;
   runtimeState._timer.pausedAt = null;
-  runtimeState._timer.pausedDuration = 0;
+  runtimeState._timer.pausedDuration = 0 as Duration;
   runtimeState._timer.secondaryTarget = null;
   runtimeState._timer.hasFinished = false;
 }
@@ -160,22 +208,18 @@ export function clearState() {
   runtimeState.rundown.actualStart = null;
   runtimeState.rundown.selectedEventIndex = null;
 
-  runtimeState.offset.absolute = 0;
+  runtimeState.offset = { ...runtimePlaceholder.offset };
-  runtimeState.offset.relative = 0;
-  runtimeState.offset.expectedRundownEnd = null;
-  runtimeState.offset.expectedGroupEnd = null;
-  runtimeState.offset.expectedFlagStart = null;
 
   runtimeState._end = null;
 
   runtimeState.timer.playback = Playback.Stop;
-  runtimeState.clock = timeCore.timeOfDayNow();
+  runtimeState._now = timeCore.now();
-  runtimeState.timer = { ...runtimeStorePlaceholder.timer };
+  runtimeState.timer = { ...runtimePlaceholder.timer };
 
   // when clearing, we maintain the total delay from the rundown
-  runtimeState._timer.forceFinish = null;
+  runtimeState._timer.forceFinish = false;
   runtimeState._timer.pausedAt = null;
-  runtimeState._timer.pausedDuration = 0;
+  runtimeState._timer.pausedDuration = 0 as Duration;
   runtimeState._timer.secondaryTarget = null;
   runtimeState._timer.hasFinished = false;
 
@@ -217,9 +261,9 @@ export function updateRundownData(rundownData: {
   runtimeState._rundown.totalDelay = rundownData.totalDelay;
 
   runtimeState.rundown.numEvents = rundownData.numEvents;
-  runtimeState.rundown.plannedStart = rundownData.firstStart;
+  runtimeState.rundown.plannedStart = rundownData.firstStart as TimeOfDay;
   runtimeState.rundown.plannedEnd =
-    rundownData.firstStart === null ? null : rundownData.firstStart + rundownData.totalDuration;
+    rundownData.firstStart === null ? null : ((rundownData.firstStart + rundownData.totalDuration) as TimeOfDay);
 
   if (isPlaybackActive(runtimeState.timer.playback)) getExpectedTimes();
 }
@@ -253,7 +297,7 @@ export function load(
 
   // update state
   runtimeState.timer.playback = Playback.Armed;
-  runtimeState.timer.duration = calculateDuration(event.timeStart, event.timeEnd);
+  runtimeState.timer.duration = event.duration as Duration;
   runtimeState.timer.current = getCurrent(runtimeState);
   runtimeState.rundown.numEvents = metadata.timedEventOrder.length;
 
@@ -267,13 +311,13 @@ export function load(
       (firstStart === null || typeof firstStart === 'number') &&
       (startEpoch === null || typeof startEpoch === 'number')
     ) {
-      runtimeState.rundown.actualStart = firstStart;
+      runtimeState.rundown.actualStart = firstStart as TimeOfDay;
       runtimeState._startEpoch = startEpoch;
       if (firstStart !== null && runtimeState.rundown.plannedStart !== null) {
         runtimeState._startDayOffset = findDayOffset(runtimeState.rundown.plannedStart, firstStart);
       }
       if (currentDay !== undefined) {
-        runtimeState.rundown.currentDay = currentDay;
+        runtimeState.rundown.currentDay = currentDay as Day;
       }
       const { absolute, relative } = getRuntimeOffset(runtimeState);
       runtimeState.offset.absolute = absolute;
@@ -365,16 +409,16 @@ export function updateLoaded(event?: PlayableEvent): string | undefined {
 
     // handle edge cases with roll
     if (runtimeState.timer.playback === Playback.Roll) {
-      const offsetClock = runtimeState.clock - runtimeState.offset.absolute;
+      const offsetClock = timeCore.toTimeOfDay(runtimeState._now) - runtimeState.offset.absolute;
       // if waiting to roll, we update the targets and potentially start the timer
       if (runtimeState._timer.secondaryTarget !== null) {
         if (runtimeState.eventNow.timeStart < offsetClock && offsetClock < runtimeState.eventNow.timeEnd) {
           // if the event is now, we queue a start
           runtimeState._timer.secondaryTarget = runtimeState.eventNow.timeStart as TimeOfDay;
-          runtimeState.timer.secondaryTimer = runtimeState._timer.secondaryTarget - offsetClock;
+          runtimeState.timer.secondaryTimer = (runtimeState._timer.secondaryTarget - offsetClock) as Duration;
         } else {
           runtimeState._timer.secondaryTarget = normaliseRollStart(
-            runtimeState.eventNow.timeStart,
+            runtimeState.eventNow.timeStart as TimeOfDay,
             offsetClock,
           ) as TimeOfDay;
         }
@@ -391,7 +435,7 @@ export function updateLoaded(event?: PlayableEvent): string | undefined {
 
   runtimeState.timer.startedAt = null;
   runtimeState._timer.hasFinished = false;
-  runtimeState.timer.addedTime = 0;
+  runtimeState.timer.addedTime = 0 as Duration;
   runtimeState._timer.pausedAt = null;
 
   // this could be looked after by the timer
@@ -414,7 +458,7 @@ export function updateAll(rundown: Rundown, metadata: RundownMetadata) {
   loadGroupFlagAndEnd(rundown, metadata, eventNowIndex);
 }
 
-export function start(state: RuntimeState = runtimeState): boolean {
+export function start(state: InternalRuntimeState = runtimeState): boolean {
   if (state.eventNow === null) {
     return false;
   }
@@ -422,22 +466,19 @@ export function start(state: RuntimeState = runtimeState): boolean {
     return false;
   }
 
-  const epoch = timeCore.now();
+  state._now = timeCore.now();
-  const now = timeCore.toTimeOfDay(epoch);
-
-  state.clock = now;
   state.timer.secondaryTimer = null;
 
   // add paused time if it exists
   if (state._timer.pausedAt) {
-    const timeToAdd = state.clock - state._timer.pausedAt;
+    const timeToAdd = (timeCore.toTimeOfDay(state._now) - state._timer.pausedAt) as Duration;
-    state.timer.addedTime += timeToAdd;
+    state.timer.addedTime = timeCore.combineValues(state.timer.addedTime, timeToAdd);
-    state._timer.pausedDuration += timeToAdd;
+    state._timer.pausedDuration = timeCore.combineValues(state._timer.pausedDuration, timeToAdd);
     state._timer.pausedAt = null;
   }
 
   if (state.timer.startedAt === null) {
-    state.timer.startedAt = state.clock;
+    state.timer.startedAt = state._now;
   }
 
   state.timer.playback = Playback.Play;
@@ -445,14 +486,15 @@ export function start(state: RuntimeState = runtimeState): boolean {
   state.timer.elapsed = getElapsed(state);
 
   if (state.rundown.actualStart === null) {
-    state._startDayOffset = (findDayOffset(state.eventNow.timeStart, state.clock) + state.eventNow.dayOffset) as Day;
+    state._startDayOffset = (findDayOffset(state.eventNow.timeStart, timeCore.toTimeOfDay(state._now)) +
+      state.eventNow.dayOffset) as Day;
     state.rundown.currentDay = state._startDayOffset;
-    state._startEpoch = epoch;
+    state._startEpoch = state._now;
-    state.rundown.actualStart = state.clock;
+    state.rundown.actualStart = timeCore.toTimeOfDay(state._now);
   }
 
   if (state.groupNow !== null && state.rundown.actualGroupStart === null) {
-    state.rundown.actualGroupStart = state.clock;
+    state.rundown.actualGroupStart = timeCore.toTimeOfDay(state._now);
   }
 
   // update timer phase
@@ -475,18 +517,18 @@ export function start(state: RuntimeState = runtimeState): boolean {
   return true;
 }
 
-export function pause(state: RuntimeState = runtimeState): boolean {
+export function pause(state: InternalRuntimeState = runtimeState): boolean {
   if (state.timer.playback !== Playback.Play) {
     return false;
   }
 
   state.timer.playback = Playback.Pause;
-  state.clock = timeCore.timeOfDayNow();
+  state._now = timeCore.now();
-  state._timer.pausedAt = state.clock;
+  state._timer.pausedAt = timeCore.toTimeOfDay(state._now);
   return true;
 }
 
-export function stop(state: RuntimeState = runtimeState): boolean {
+export function stop(state: InternalRuntimeState = runtimeState): boolean {
   if (state.timer.playback === Playback.Stop) {
     return false;
   }
@@ -516,7 +558,7 @@ export function addTime(amount: number) {
 
   if (willGoNegative && !runtimeState._timer.hasFinished) {
     // set finished time so side effects are triggered
-    runtimeState._timer.forceFinish = timeCore.timeOfDayNow();
+    runtimeState._timer.forceFinish = true;
   } else {
     const willGoPositive = runtimeState.timer.current < 0 && runtimeState.timer.current + amount > 0;
     if (willGoPositive) {
@@ -525,8 +567,8 @@ export function addTime(amount: number) {
   }
 
   // we can update the state after handling the side effects
-  runtimeState.timer.addedTime += amount;
+  runtimeState.timer.addedTime = timeCore.combineValues(runtimeState.timer.addedTime, amount as Duration);
-  runtimeState.timer.current += amount;
+  runtimeState.timer.current = timeCore.combineValues(runtimeState.timer.current, amount as Duration);
   runtimeState.timer.elapsed = getElapsed(runtimeState);
 
   // update runtime delays: over - under
@@ -546,10 +588,8 @@ export type UpdateResult = {
 
 export function update(): UpdateResult {
   // 0. there are some things we always do
-  const previousClock = runtimeState.clock;
+  const previousClock = timeCore.toTimeOfDay(runtimeState._now);
-  const epoch = timeCore.now();
+  runtimeState._now = timeCore.now(); // we update the clock on every update call
-  const now = timeCore.toTimeOfDay(epoch);
-  runtimeState.clock = now; // we update the clock on every update call
 
   // 1. is playback idle?
   if (!isPlaybackActive(runtimeState.timer.playback)) {
@@ -558,13 +598,13 @@ export function update(): UpdateResult {
 
   // calculate currentDay from epoch (days elapsed since playback was started)
   if (runtimeState._startEpoch !== null && runtimeState._startDayOffset !== null) {
-    const daysSinceStart = timeCore.daysSinceStart(runtimeState._startEpoch, epoch);
+    const daysSinceStart = timeCore.daysSinceStart(runtimeState._startEpoch, runtimeState._now);
-    runtimeState.rundown.currentDay = runtimeState._startDayOffset + daysSinceStart;
+    runtimeState.rundown.currentDay = timeCore.combineValues(runtimeState._startDayOffset, daysSinceStart);
   }
 
   // 2. are we waiting to roll?
   if (runtimeState.timer.playback === Playback.Roll && runtimeState.timer.secondaryTimer !== null) {
-    const clockHasCrossedMidnight = hasCrossedMidnight(previousClock, now);
+    const clockHasCrossedMidnight = hasCrossedMidnight(previousClock, timeCore.toTimeOfDay(runtimeState._now));
     return updateIfWaitingToRoll(clockHasCrossedMidnight);
   }
 
@@ -618,22 +658,24 @@ export function update(): UpdateResult {
     }
 
     // account for offset
-    const offsetClock = runtimeState.clock + runtimeState.offset.absolute;
+    const offsetClock = timeCore.toTimeOfDay(
+      timeCore.addDuration(runtimeState._now, runtimeState.offset.absolute as Duration),
+    );
     runtimeState.timer.phase = TimerPhase.Pending;
 
     if (hasCrossedMidnight) {
       // if we crossed midnight, we need to update the target
       // this is the same logic from the roll function
       runtimeState._timer.secondaryTarget = normaliseRollStart(
-        runtimeState.eventNow.timeStart,
+        runtimeState.eventNow.timeStart as TimeOfDay,
         offsetClock,
       ) as TimeOfDay;
     }
 
-    runtimeState.timer.secondaryTimer = runtimeState._timer.secondaryTarget! - offsetClock;
+    runtimeState.timer.secondaryTimer = (runtimeState._timer.secondaryTarget! - offsetClock) as Duration;
     return {
       hasTimerFinished: false,
-      hasSecondaryTimerFinished: runtimeState.timer.secondaryTimer <= 0,
+      hasSecondaryTimerFinished: runtimeState.timer.secondaryTimer! <= 0,
     };
   }
 }
@@ -650,9 +692,7 @@ export function roll(
   }
 
   // we will need to do some calculations, update the time first
-  const epoch = timeCore.now();
+  runtimeState._now = timeCore.now();
-  const now = timeCore.toTimeOfDay(epoch);
-  runtimeState.clock = now;
 
   // 2. if there is an event armed, we use it
   if (runtimeState.timer.playback === Playback.Armed || runtimeState.timer.phase === TimerPhase.Pending) {
@@ -664,7 +704,9 @@ export function roll(
     }
 
     if (offset) {
-      runtimeState.offset = { ...offset };
+      runtimeState.offset = {
+        ...offset,
+      } as InternalRuntimeState['offset'];
     }
     runtimeState.timer.playback = Playback.Roll;
 
@@ -673,15 +715,16 @@ export function roll(
       runtimeState.eventNow.timeEnd < runtimeState.eventNow.timeStart
         ? runtimeState.eventNow.timeEnd + dayInMs
         : runtimeState.eventNow.timeEnd;
-    runtimeState.timer.expectedFinish = normalisedEndTime;
+    runtimeState.timer.expectedFinish = normalisedEndTime as TimeOfDay;
 
     // account for offset
-    const offsetClock = runtimeState.clock - runtimeState.offset.absolute;
+    // const offsetClock = timeCore.addDuration(runtimeState._now, -runtimeState.offset.absolute as Duration);
+    const offsetClock = timeCore.toTimeOfDay(runtimeState._now) - runtimeState.offset.absolute;
 
     // state catch up
     runtimeState.timer.duration = calculateDuration(runtimeState.eventNow.timeStart, normalisedEndTime);
     runtimeState.timer.current = runtimeState.timer.duration;
-    runtimeState.timer.elapsed = 0;
+    runtimeState.timer.elapsed = 0 as Duration;
 
     // check if the event is ready to start or if needs to be pending
     const isNow = checkIsNow(runtimeState.eventNow.timeStart, runtimeState.eventNow.timeEnd, offsetClock);
@@ -690,8 +733,8 @@ export function roll(
        * If we are starting an event in roll mode
        * we backtrace all the start times to the supposed start time of the event
        */
-      const plannedStart = runtimeState.eventNow.timeStart;
+      const plannedStart = runtimeState.eventNow.timeStart as TimeOfDay;
-      runtimeState.timer.startedAt = plannedStart;
+      runtimeState.timer.startedAt = timeCore.toInstant(plannedStart, runtimeState._now);
       // reset the secondary timer to cancel any countdowns
       runtimeState.timer.secondaryTimer = null;
 
@@ -709,18 +752,20 @@ export function roll(
         runtimeState._startDayOffset = (findDayOffset(runtimeState.eventNow.timeStart, plannedStart) +
           runtimeState.eventNow.dayOffset) as Day;
         // backdate _startEpoch to when the event conceptually started
-        const timeElapsed = timeCore.elapsedTime(runtimeState.clock, plannedStart as TimeOfDay);
+        const timeElapsed = timeCore.elapsedTime(timeCore.toTimeOfDay(runtimeState._now), plannedStart as TimeOfDay);
-        runtimeState._startEpoch = timeCore.addDuration(epoch, -timeElapsed as Duration);
+        runtimeState._startEpoch = timeCore.addDuration(runtimeState._now, -timeElapsed as Duration);
         // calculate currentDay from the backdated epoch
-        runtimeState.rundown.currentDay =
+        runtimeState.rundown.currentDay = timeCore.combineValues(
-          runtimeState._startDayOffset + timeCore.daysSinceStart(runtimeState._startEpoch, epoch);
+          runtimeState._startDayOffset,
+          timeCore.daysSinceStart(runtimeState._startEpoch, runtimeState._now),
+        );
       }
     } else {
       runtimeState._timer.secondaryTarget = normaliseRollStart(
-        runtimeState.eventNow.timeStart,
+        runtimeState.eventNow.timeStart as TimeOfDay,
         offsetClock,
       ) as TimeOfDay;
-      runtimeState.timer.secondaryTimer = runtimeState._timer.secondaryTarget - offsetClock;
+      runtimeState.timer.secondaryTimer = (runtimeState._timer.secondaryTarget - offsetClock) as Duration;
       runtimeState.timer.phase = TimerPhase.Pending;
     }
 
@@ -737,9 +782,9 @@ export function roll(
 
   // account for offset but we only keep it if passed to us
   if (offset) {
-    runtimeState.offset = { ...offset };
+    runtimeState.offset = { ...offset } as InternalRuntimeState['offset'];
   }
-  const offsetClock = runtimeState.clock - runtimeState.offset.absolute;
+  const offsetClock = timeCore.toTimeOfDay(runtimeState._now) - runtimeState.offset.absolute;
 
   const { index, isPending } = loadRoll(rundown, metadata, offsetClock);
 
@@ -766,7 +811,7 @@ export function roll(
     runtimeState.timer.phase = TimerPhase.Pending;
     // we need to normalise start time in case it is the day after
     runtimeState._timer.secondaryTarget = normaliseRollStart(runtimeState.eventNow.timeStart, offsetClock) as TimeOfDay;
-    runtimeState.timer.secondaryTimer = runtimeState._timer.secondaryTarget - offsetClock;
+    runtimeState.timer.secondaryTimer = (runtimeState._timer.secondaryTarget - offsetClock) as Duration;
 
     // preload timer properties
     runtimeState.timer.duration = calculateDuration(runtimeState.eventNow.timeStart, runtimeState.eventNow.timeEnd);
@@ -789,18 +834,18 @@ export function roll(
    * when we start in roll mode
    * we need to backtrace all times to the supposed start time of the event
    */
-  const plannedStart = runtimeState.eventNow.timeStart;
+  const plannedStart = runtimeState.eventNow.timeStart as TimeOfDay;
   const endTime =
     runtimeState.eventNow.timeEnd < runtimeState.eventNow.timeStart
       ? runtimeState.eventNow.timeEnd + dayInMs
       : runtimeState.eventNow.timeEnd;
-  runtimeState.timer.startedAt = plannedStart;
+  runtimeState.timer.startedAt = timeCore.toInstant(plannedStart, runtimeState._now);
-  runtimeState.timer.expectedFinish = endTime;
+  runtimeState.timer.expectedFinish = endTime as TimeOfDay;
 
   // state catch up
   runtimeState.timer.duration = calculateDuration(runtimeState.eventNow.timeStart, endTime);
   runtimeState.timer.current = getCurrent(runtimeState);
-  runtimeState.timer.elapsed = 0;
+  runtimeState.timer.elapsed = 0 as Duration;
 
   // update runtime
   runtimeState.rundown.actualStart = plannedStart;
@@ -813,11 +858,11 @@ export function roll(
   runtimeState._startDayOffset = (findDayOffset(runtimeState.eventNow.timeStart, plannedStart) +
     runtimeState.eventNow.dayOffset) as Day;
   // backdate _startEpoch to when the event conceptually started
-  const timeElapsed = timeCore.elapsedTime(runtimeState.clock, plannedStart as TimeOfDay);
+  const timeElapsed = timeCore.elapsedTime(timeCore.toTimeOfDay(runtimeState._now), plannedStart as TimeOfDay);
-  runtimeState._startEpoch = timeCore.addDuration(epoch, -timeElapsed as Duration);
+  runtimeState._startEpoch = timeCore.addDuration(runtimeState._now, -timeElapsed as Duration);
   // calculate currentDay from the backdated epoch
   runtimeState.rundown.currentDay = (runtimeState._startDayOffset +
-    timeCore.daysSinceStart(runtimeState._startEpoch, epoch)) as Day;
+    timeCore.daysSinceStart(runtimeState._startEpoch, runtimeState._now)) as Day;
 
   return { eventId: runtimeState.eventNow.id, didStart: true };
 }
@@ -852,7 +897,11 @@ function getExpectedTimes(state = runtimeState) {
         plannedStart,
         actualStart,
       });
-      state.offset.expectedGroupEnd = getExpectedEnd(lastEvent, lastEventExpectedStart, state.rundown.currentDay!);
+      state.offset.expectedGroupEnd = getExpectedEnd(
+        lastEvent,
+        lastEventExpectedStart,
+        state.rundown.currentDay!,
+      ) as TimeOfDay;
     }
   }
 
@@ -869,7 +918,7 @@ function getExpectedTimes(state = runtimeState) {
         plannedStart,
         actualStart,
       });
-      state.offset.expectedFlagStart = expectedStart;
+      state.offset.expectedFlagStart = expectedStart as TimeOfDay;
     }
   }
 
@@ -884,7 +933,7 @@ function getExpectedTimes(state = runtimeState) {
       plannedStart,
       actualStart,
     });
-    state.offset.expectedRundownEnd = getExpectedEnd(event, expectedStart, state.rundown.currentDay!);
+    state.offset.expectedRundownEnd = getExpectedEnd(event, expectedStart, state.rundown.currentDay!) as TimeOfDay;
   }
 }
 
@@ -957,13 +1006,13 @@ export function loadGroupFlagAndEnd(
         if (!foundFlag && metadata.flags.includes(entry.id)) {
           foundFlag = true;
           state.eventFlag = entry as PlayableEvent; // we know it is playable as it is coming from the playableEventOrder list
-          state._flag = { event: entry, isLinkedToLoaded, accumulatedGap };
+          state._flag = { event: entry, isLinkedToLoaded, accumulatedGap: accumulatedGap as Duration };
         }
       }
 
       if (!foundGroupEnd && entry.id === lastEventInGroup?.id) {
         foundGroupEnd = true;
-        state._group = { event: lastEventInGroup, isLinkedToLoaded, accumulatedGap };
+        state._group = { event: lastEventInGroup, isLinkedToLoaded, accumulatedGap: accumulatedGap as Duration };
       }
     }
   }
@@ -971,7 +1020,7 @@ export function loadGroupFlagAndEnd(
   const lastID = playableEventOrder.at(-1);
   const lastEvent = lastID ? (entries[lastID] as OntimeEvent) : null;
   if (lastEvent) {
-    state._end = { event: lastEvent, isLinkedToLoaded, accumulatedGap };
+    state._end = { event: lastEvent, isLinkedToLoaded, accumulatedGap: accumulatedGap as Duration };
   }
 }
 

packages/utils/src/validate-times/validateTimes.ts

@@ -1,4 +1,4 @@
-import type { OntimeEvent } from 'ontime-types';
+import type { Duration, OntimeEvent } from 'ontime-types';
 import { TimeStrategy } from 'ontime-types';
 
 import { dayInMs } from '../date-utils/conversionUtils.js';
@@ -103,16 +103,17 @@ export function validateTimes(
 
 /**
  * @description calculates event duration considering midnight
+ * @deprecated - duration is the more useful value from the event data, prefer using that directly
  * @param {number} timeStart
  * @param {number} timeEnd
  * @returns {number}
  */
-export function calculateDuration(timeStart: number, timeEnd: number): number {
+export function calculateDuration(timeStart: number, timeEnd: number): Duration {
   // Durations must be positive
   if (timeEnd < timeStart) {
-    return timeEnd + dayInMs - timeStart;
+    return (timeEnd + dayInMs - timeStart) as Duration;
   }
-  return timeEnd - timeStart;
+  return (timeEnd - timeStart) as Duration;
 }
 
 export function calculateEnd(timeStart: number, duration: number): number {