Feat resumability (#547)

* add resumability functionality

---------

Co-authored-by: arc-alex <ac@omnivox.dk>
Co-authored-by: Carlos Valente <34649812+cpvalente@users.noreply.github.com>

apps/server/src/services/PlaybackService.ts

@@ -1,4 +1,4 @@
-import { LogOrigin, OntimeEvent } from 'ontime-types';
+import { LogOrigin, OntimeEvent, Playback } from 'ontime-types';
 import { validatePlayback } from 'ontime-utils';
 
 import { eventLoader, EventLoader } from '../classes/event-loader/EventLoader.js';
@@ -6,6 +6,7 @@ import { eventStore } from '../stores/EventStore.js';
 import { eventTimer } from './TimerService.js';
 import { clock } from './Clock.js';
 import { logger } from '../classes/Logger.js';
+import { RestorePoint } from './RestoreService.js';
 
 /**
  * Service manages playback status of app
@@ -241,6 +242,33 @@ export class PlaybackService {
     }
   }
 
+  /**
+   * @description resume playback state given a restore point
+   * @param restorePoint
+   */
+  static resume(restorePoint: RestorePoint) {
+    const willResume = () => logger.info(LogOrigin.Server, 'Resuming playback');
+
+    if (restorePoint.playback === Playback.Roll) {
+      willResume();
+      PlaybackService.roll();
+    }
+
+    if (restorePoint.selectedEventId) {
+      const event = EventLoader.getEventWithId(restorePoint.selectedEventId);
+      // the db would have to change for the event not to exist
+      // we do not kow the reason for the crash, so we check anyway
+      if (!event) {
+        return;
+      }
+
+      eventLoader.loadEvent(event);
+      eventTimer.resume(event, restorePoint);
+      eventStore.broadcast();
+      return;
+    }
+  }
+
   /**
    * Adds delay to current event
    * @param {number} delayTime time in minutes