fix(core): update

ts/smarttime.classes.cronjob.ts

@@ -4,48 +4,37 @@ import { CronManager } from './smarttime.classes.cronmanager';
 export type TJobFunction = (() => void) | (() => Promise<any>);
 
 export class CronJob {
+  public croner; 
   public status: 'started' | 'stopped' | 'initial' = 'initial';
   public cronExpression: string;
   public jobFunction: TJobFunction;
-
-  private cronInterval = plugins.cronParser.parseExpression('* * * * * *');
   private nextExecutionUnix: number = 0;
 
   constructor(cronManager: CronManager, cronExpressionArg: string, jobFunction: TJobFunction) {
     this.cronExpression = cronExpressionArg;
     this.jobFunction = jobFunction;
+    this.croner = plugins.croner(this.cronExpression);
   }
 
   /**
    * checks wether the cronjob needs to be executed
    */
-  public checkExecution() {
+  public checkExecution(): number {
     if (this.nextExecutionUnix === 0) {
-      this.nextExecutionUnix = this.cronInterval
-        .next()
-        .toDate()
-        .getTime();
-      return;
+      this.nextExecutionUnix = this.croner.msToNext();
     }
     if (Date.now() > this.nextExecutionUnix) {
       this.jobFunction();
-      this.nextExecutionUnix = this.cronInterval
-        .next()
-        .toDate()
-        .getTime();
+      this.nextExecutionUnix = this.croner.msToNext();
     }
+    return this.nextExecutionUnix;
   }
 
   public start() {
-    this.cronInterval = this.getCronInterval();
     this.status = 'started';
   }
 
   public stop() {
     this.status = 'stopped';
   }
-
-  private getCronInterval() {
-    return plugins.cronParser.parseExpression(this.cronExpression);
-  }
 }