From 6eaece99c53a3e6bc56caea8a52a9fffc9606a04 Mon Sep 17 00:00:00 2001
From: "Jonathan Leibiusky @xetorthio" <ionathan@gmail.com>
Date: Wed, 12 Jul 2017 21:46:57 -0300
Subject: [PATCH] Add events

---
 event/event.go             | 16 ++++++++++++++++
 event/local_broker.go      | 34 ++++++++++++++++++++++++++++++++++
 event/local_broker_test.go | 31 +++++++++++++++++++++++++++++++
 3 files changed, 81 insertions(+)
 create mode 100644 event/event.go
 create mode 100644 event/local_broker.go
 create mode 100644 event/local_broker_test.go

diff --git a/event/event.go b/event/event.go
new file mode 100644
index 0000000..6a6541f
--- /dev/null
+++ b/event/event.go
@@ -0,0 +1,16 @@
+package event
+
+type EventType string
+
+const INSTANCE_VIEWPORT_RESIZE EventType = "instance viewport resize"
+const INSTANCE_DELETE EventType = "instance delete"
+const INSTANCE_NEW EventType = "instance new"
+const SESSION_END EventType = "session end"
+const SESSION_READY EventType = "session ready"
+
+type Handler func(args ...interface{})
+
+type EventApi interface {
+	Emit(name EventType, args ...interface{})
+	On(name EventType, handler Handler)
+}
diff --git a/event/local_broker.go b/event/local_broker.go
new file mode 100644
index 0000000..da68dd4
--- /dev/null
+++ b/event/local_broker.go
@@ -0,0 +1,34 @@
+package event
+
+import "sync"
+
+type localBroker struct {
+	sync.Mutex
+
+	handlers map[EventType][]Handler
+}
+
+func NewLocalBroker() *localBroker {
+	return &localBroker{handlers: map[EventType][]Handler{}}
+}
+
+func (b *localBroker) On(name EventType, handler Handler) {
+	b.Lock()
+	defer b.Unlock()
+
+	if b.handlers[name] == nil {
+		b.handlers[name] = []Handler{}
+	}
+	b.handlers[name] = append(b.handlers[name], handler)
+}
+
+func (b *localBroker) Emit(name EventType, args ...interface{}) {
+	b.Lock()
+	defer b.Unlock()
+
+	if b.handlers[name] != nil {
+		for _, handler := range b.handlers[name] {
+			handler(args...)
+		}
+	}
+}
diff --git a/event/local_broker_test.go b/event/local_broker_test.go
new file mode 100644
index 0000000..777a4b8
--- /dev/null
+++ b/event/local_broker_test.go
@@ -0,0 +1,31 @@
+package event
+
+import (
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestLocalBroker(t *testing.T) {
+	broker := NewLocalBroker()
+
+	called := 0
+	receivedArgs := []interface{}{}
+
+	wg := sync.WaitGroup{}
+	wg.Add(1)
+
+	broker.On(INSTANCE_NEW, func(args ...interface{}) {
+		called++
+		receivedArgs = args
+		wg.Done()
+	})
+	broker.Emit(SESSION_READY)
+	broker.Emit(INSTANCE_NEW, "foo", "bar")
+
+	wg.Wait()
+
+	assert.Equal(t, 1, called)
+	assert.Equal(t, []interface{}{"foo", "bar"}, receivedArgs)
+}