From e960afe8f6263689bc98c53612cec04d859f8987 Mon Sep 17 00:00:00 2001
From: Lea Anthony <lea.anthony@gmail.com>
Date: Sat, 3 Oct 2020 15:10:38 +1000
Subject: [PATCH] Support OnMultiple

---
 .gitignore                              |  2 ++
 v2/internal/runtime/goruntime/events.go | 17 +++++++++++++++--
 v2/test/runtime/runtime.go              |  3 +++
 3 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/.gitignore b/.gitignore
index bc455bc50..07e284f19 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,3 +22,5 @@ v2/test/**/frontend/dist
 v2/test/**/build/
 v2/test/frameless/icon.png
 v2/test/hidden/icon.png
+v2/internal/ffenestri/runtime.c
+v2/internal/runtime/assets/desktop.js
diff --git a/v2/internal/runtime/goruntime/events.go b/v2/internal/runtime/goruntime/events.go
index 850166d1c..d370f5fec 100644
--- a/v2/internal/runtime/goruntime/events.go
+++ b/v2/internal/runtime/goruntime/events.go
@@ -9,6 +9,7 @@ import (
 type Events interface {
 	On(eventName string, callback func(optionalData ...interface{}))
 	Once(eventName string, callback func(optionalData ...interface{}))
+	OnMultiple(eventName string, callback func(optionalData ...interface{}), maxCallbacks int)
 	Emit(eventName string, optionalData ...interface{})
 }
 
@@ -24,7 +25,7 @@ func newEvents(bus *servicebus.ServiceBus) Events {
 	}
 }
 
-// On pass through
+// On registers a listener for a particular event
 func (r *event) On(eventName string, callback func(optionalData ...interface{})) {
 	eventMessage := &message.OnEventMessage{
 		Name:     eventName,
@@ -34,7 +35,8 @@ func (r *event) On(eventName string, callback func(optionalData ...interface{}))
 	r.bus.Publish("event:on", eventMessage)
 }
 
-// On pass through
+// Once registers a listener for a particular event. After the first callback, the
+// listener is deleted.
 func (r *event) Once(eventName string, callback func(optionalData ...interface{})) {
 	eventMessage := &message.OnEventMessage{
 		Name:     eventName,
@@ -44,6 +46,17 @@ func (r *event) Once(eventName string, callback func(optionalData ...interface{}
 	r.bus.Publish("event:on", eventMessage)
 }
 
+// OnMultiple registers a listener for a particular event, for a given maximum amount of callbacks.
+// Once the callback has been run `maxCallbacks` times, the listener is deleted.
+func (r *event) OnMultiple(eventName string, callback func(optionalData ...interface{}), maxCallbacks int) {
+	eventMessage := &message.OnEventMessage{
+		Name:     eventName,
+		Callback: callback,
+		Counter:  maxCallbacks,
+	}
+	r.bus.Publish("event:on", eventMessage)
+}
+
 // Emit pass through
 func (r *event) Emit(eventName string, optionalData ...interface{}) {
 	eventMessage := &message.EventMessage{
diff --git a/v2/test/runtime/runtime.go b/v2/test/runtime/runtime.go
index f3c10fe55..632937332 100644
--- a/v2/test/runtime/runtime.go
+++ b/v2/test/runtime/runtime.go
@@ -26,6 +26,9 @@ func (r *RuntimeTest) WailsInit(runtime *wails.Runtime) error {
 	r.runtime.Events.Once("testeventonce", func(optionalParams ...interface{}) {
 		println("I only get called once!")
 	})
+	r.runtime.Events.OnMultiple("testeventmultiple", func(optionalParams ...interface{}) {
+		println("I only get called 3 times!")
+	}, 3)
 	return nil
 }