improvement on computing ordinal on mutliplicity fields

dmp-frontend/src/app/ui/misc/dataset-description-form/components/form-section/form-section.component.ts

@@ -74,8 +74,17 @@ export class FormSectionComponent implements OnInit, OnChanges {
 	addMultipleField(fieldsetIndex: number) {
 		const compositeFieldToBeCloned = (this.form.get('compositeFields').get('' + fieldsetIndex) as FormGroup).getRawValue();
 		const multiplicityItemsArray = (<FormArray>(this.form.get('compositeFields').get('' + fieldsetIndex).get('multiplicityItems')));
+
+		const ordinal = multiplicityItemsArray.length? multiplicityItemsArray.controls.reduce((ordinal, currentControl)=>{
+			const currentOrdinal = currentControl.get('ordinal').value as number;
+
+			if(currentOrdinal>= ordinal){
+				return currentOrdinal +1;
+			}
+			return ordinal as number;
+		},0) : 0;
 		const idMappings = [] as {old: string, new: string}[];
-		const compositeField: DatasetDescriptionCompositeFieldEditorModel = new DatasetDescriptionCompositeFieldEditorModel().cloneForMultiplicity(compositeFieldToBeCloned, multiplicityItemsArray.length,idMappings);
+		const compositeField: DatasetDescriptionCompositeFieldEditorModel = new DatasetDescriptionCompositeFieldEditorModel().cloneForMultiplicity(compositeFieldToBeCloned, ordinal ,idMappings);