Update vendor

vendor/github.com/bwmarrin/discordgo/event.go

@@ -0,0 +1,238 @@
+package discordgo
+
+import "fmt"
+
+// EventHandler is an interface for Discord events.
+type EventHandler interface {
+	// Type returns the type of event this handler belongs to.
+	Type() string
+
+	// Handle is called whenever an event of Type() happens.
+	// It is the recievers responsibility to type assert that the interface
+	// is the expected struct.
+	Handle(*Session, interface{})
+}
+
+// EventInterfaceProvider is an interface for providing empty interfaces for
+// Discord events.
+type EventInterfaceProvider interface {
+	// Type is the type of event this handler belongs to.
+	Type() string
+
+	// New returns a new instance of the struct this event handler handles.
+	// This is called once per event.
+	// The struct is provided to all handlers of the same Type().
+	New() interface{}
+}
+
+// interfaceEventType is the event handler type for interface{} events.
+const interfaceEventType = "__INTERFACE__"
+
+// interfaceEventHandler is an event handler for interface{} events.
+type interfaceEventHandler func(*Session, interface{})
+
+// Type returns the event type for interface{} events.
+func (eh interfaceEventHandler) Type() string {
+	return interfaceEventType
+}
+
+// Handle is the handler for an interface{} event.
+func (eh interfaceEventHandler) Handle(s *Session, i interface{}) {
+	eh(s, i)
+}
+
+var registeredInterfaceProviders = map[string]EventInterfaceProvider{}
+
+// registerInterfaceProvider registers a provider so that DiscordGo can
+// access it's New() method.
+func registerInterfaceProvider(eh EventInterfaceProvider) error {
+	if _, ok := registeredInterfaceProviders[eh.Type()]; ok {
+		return fmt.Errorf("event %s already registered", eh.Type())
+	}
+	registeredInterfaceProviders[eh.Type()] = eh
+	return nil
+}
+
+// eventHandlerInstance is a wrapper around an event handler, as functions
+// cannot be compared directly.
+type eventHandlerInstance struct {
+	eventHandler EventHandler
+}
+
+// addEventHandler adds an event handler that will be fired anytime
+// the Discord WSAPI matching eventHandler.Type() fires.
+func (s *Session) addEventHandler(eventHandler EventHandler) func() {
+	s.handlersMu.Lock()
+	defer s.handlersMu.Unlock()
+
+	if s.handlers == nil {
+		s.handlers = map[string][]*eventHandlerInstance{}
+	}
+
+	ehi := &eventHandlerInstance{eventHandler}
+	s.handlers[eventHandler.Type()] = append(s.handlers[eventHandler.Type()], ehi)
+
+	return func() {
+		s.removeEventHandlerInstance(eventHandler.Type(), ehi)
+	}
+}
+
+// addEventHandler adds an event handler that will be fired the next time
+// the Discord WSAPI matching eventHandler.Type() fires.
+func (s *Session) addEventHandlerOnce(eventHandler EventHandler) func() {
+	s.handlersMu.Lock()
+	defer s.handlersMu.Unlock()
+
+	if s.onceHandlers == nil {
+		s.onceHandlers = map[string][]*eventHandlerInstance{}
+	}
+
+	ehi := &eventHandlerInstance{eventHandler}
+	s.onceHandlers[eventHandler.Type()] = append(s.onceHandlers[eventHandler.Type()], ehi)
+
+	return func() {
+		s.removeEventHandlerInstance(eventHandler.Type(), ehi)
+	}
+}
+
+// AddHandler allows you to add an event handler that will be fired anytime
+// the Discord WSAPI event that matches the function fires.
+// events.go contains all the Discord WSAPI events that can be fired.
+// eg:
+//     Session.AddHandler(func(s *discordgo.Session, m *discordgo.MessageCreate) {
+//     })
+//
+// or:
+//     Session.AddHandler(func(s *discordgo.Session, m *discordgo.PresenceUpdate) {
+//     })
+// The return value of this method is a function, that when called will remove the
+// event handler.
+func (s *Session) AddHandler(handler interface{}) func() {
+	eh := handlerForInterface(handler)
+
+	if eh == nil {
+		s.log(LogError, "Invalid handler type, handler will never be called")
+		return func() {}
+	}
+
+	return s.addEventHandler(eh)
+}
+
+// AddHandlerOnce allows you to add an event handler that will be fired the next time
+// the Discord WSAPI event that matches the function fires.
+// See AddHandler for more details.
+func (s *Session) AddHandlerOnce(handler interface{}) func() {
+	eh := handlerForInterface(handler)
+
+	if eh == nil {
+		s.log(LogError, "Invalid handler type, handler will never be called")
+		return func() {}
+	}
+
+	return s.addEventHandlerOnce(eh)
+}
+
+// removeEventHandler instance removes an event handler instance.
+func (s *Session) removeEventHandlerInstance(t string, ehi *eventHandlerInstance) {
+	s.handlersMu.Lock()
+	defer s.handlersMu.Unlock()
+
+	handlers := s.handlers[t]
+	for i := range handlers {
+		if handlers[i] == ehi {
+			s.handlers[t] = append(handlers[:i], handlers[i+1:]...)
+		}
+	}
+
+	onceHandlers := s.onceHandlers[t]
+	for i := range onceHandlers {
+		if onceHandlers[i] == ehi {
+			s.onceHandlers[t] = append(onceHandlers[:i], handlers[i+1:]...)
+		}
+	}
+}
+
+// Handles calling permanent and once handlers for an event type.
+func (s *Session) handle(t string, i interface{}) {
+	for _, eh := range s.handlers[t] {
+		go eh.eventHandler.Handle(s, i)
+	}
+
+	if len(s.onceHandlers[t]) > 0 {
+		for _, eh := range s.onceHandlers[t] {
+			go eh.eventHandler.Handle(s, i)
+		}
+		s.onceHandlers[t] = nil
+	}
+}
+
+// Handles an event type by calling internal methods, firing handlers and firing the
+// interface{} event.
+func (s *Session) handleEvent(t string, i interface{}) {
+	s.handlersMu.RLock()
+	defer s.handlersMu.RUnlock()
+
+	// All events are dispatched internally first.
+	s.onInterface(i)
+
+	// Then they are dispatched to anyone handling interface{} events.
+	s.handle(interfaceEventType, i)
+
+	// Finally they are dispatched to any typed handlers.
+	s.handle(t, i)
+}
+
+// setGuildIds will set the GuildID on all the members of a guild.
+// This is done as event data does not have it set.
+func setGuildIds(g *Guild) {
+	for _, c := range g.Channels {
+		c.GuildID = g.ID
+	}
+
+	for _, m := range g.Members {
+		m.GuildID = g.ID
+	}
+
+	for _, vs := range g.VoiceStates {
+		vs.GuildID = g.ID
+	}
+}
+
+// onInterface handles all internal events and routes them to the appropriate internal handler.
+func (s *Session) onInterface(i interface{}) {
+	switch t := i.(type) {
+	case *Ready:
+		for _, g := range t.Guilds {
+			setGuildIds(g)
+		}
+		s.onReady(t)
+	case *GuildCreate:
+		setGuildIds(t.Guild)
+	case *GuildUpdate:
+		setGuildIds(t.Guild)
+	case *Resumed:
+		s.onResumed(t)
+	case *VoiceServerUpdate:
+		go s.onVoiceServerUpdate(t)
+	case *VoiceStateUpdate:
+		go s.onVoiceStateUpdate(t)
+	}
+	s.State.onInterface(s, i)
+}
+
+// onReady handles the ready event.
+func (s *Session) onReady(r *Ready) {
+
+	// Store the SessionID within the Session struct.
+	s.sessionID = r.SessionID
+
+	// Start the heartbeat to keep the connection alive.
+	go s.heartbeat(s.wsConn, s.listening, r.HeartbeatInterval)
+}
+
+// onResumed handles the resumed event.
+func (s *Session) onResumed(r *Resumed) {
+
+	// Start the heartbeat to keep the connection alive.
+	go s.heartbeat(s.wsConn, s.listening, r.HeartbeatInterval)
+}