added url to json

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

de.srsoftware.cal.api/src/main/java/de/srsoftware/cal/api/Appointment.java

@@ -52,9 +52,10 @@ public interface Appointment {
 
 	/**
 	 * get a json representation of this Appointment
+	 * @param urlTemplate the url to put into the ical, with "{}" being replaced by the appointment id
 	 * @return a JSON Object
 	 */
-	JSONObject json();
+	JSONObject json(String urlTemplate);
 
 	/**
 	 * set of Links that point to related information

de.srsoftware.cal.base/src/main/java/de/srsoftware/cal/BaseAppointment.java

@@ -150,7 +150,7 @@ public class BaseAppointment implements Appointment {
 	}
 
 	@Override
-	public JSONObject json() {
+	public JSONObject json(String urlTemplate) {
 		var json = new JSONObject();
 		json.put("attachments", attachments.stream().map(Attachment::json).toList());
 		json.put("coords", nullable(coords).map(Coords::json).orElse(null));
@@ -162,7 +162,7 @@ public class BaseAppointment implements Appointment {
 		json.put("tags", tags());
 		json.put("title", title());
 		json.put("links", links().stream().map(Link::json).toList());
-
+		json.put("url",urlTemplate.replace("{}",""+id()));
 		return json;
 	}