feat: create branded types to determine different handling of time

packages/types/src/definitions/core/Temporal.ts

@@ -0,0 +1,15 @@
+declare const __brand: unique symbol;
+type Brand<B> = { [__brand]: B };
+type Branded<T, B> = T & Brand<B>;
+
+/** A timestamp in milliseconds from epoch */
+export type Instant = Branded<number, 'instant'>;
+
+/** A timestamp of milliseconds since midnight today in the set timezone */
+export type TimeOfDay = Branded<number, 'time-of-day'>;
+
+/** A duration of milliseconds */
+export type Duration = Branded<number, 'duration'>;
+
+/** A day count integer */
+export type Day = Branded<number, 'day'>;

packages/types/src/index.ts

@@ -20,6 +20,9 @@ export type { RundownEntries, Rundown, ProjectRundowns } from './definitions/cor
 export { TimeStrategy } from './definitions/TimeStrategy.type.js';
 export { TimerType } from './definitions/TimerType.type.js';
 
+// ---> Core
+export type { Day, Duration, Instant, TimeOfDay } from './definitions/core/Temporal.js';
+
 // ---> Report
 export type { OntimeReport, OntimeEventReport } from './definitions/core/Report.type.js';
 
@@ -125,7 +128,7 @@ export {
   isOntimeAction,
   isTimerLifeCycle,
 } from './utils/guards.js';
-export type { MaybeNumber, MaybeString } from './utils/utils.type.js';
+export type { Maybe, MaybeNumber, MaybeString } from './utils/utils.type.js';
 
 // Colour
 export type { RGBColour } from './definitions/Colour.type.js';

packages/types/src/utils/utils.type.ts

@@ -1,2 +1,4 @@
 export type MaybeNumber = number | null;
 export type MaybeString = string | null;
+
+export type Maybe<T> = T | null;