feat: westworldwithmessaging. add entitymanager, telegram, messagehandlers, delayedmessages, expand baseentity

chapter-2-state-driven-agent-design/westworldwithmessaging/state_machine.go

@@ -1,4 +1,4 @@
-package westworldwithwoman
+package westworldwithmessaging
 
 // StateMachine is the Go version of the C++ class template:
 //
@@ -129,3 +129,25 @@ func (sm *StateMachine[T]) PreviousState() State[T] {
 func (sm *StateMachine[T]) IsInState(st State[T]) bool {
 	return sm.currentState == st
 }
+
+// HandleMessage is the Go version of StateMachine::HandleMessage. A
+// telegram is offered to the current state first; if that state
+// doesn't have code in place to deal with this particular message
+// (OnMessage returns false), it's offered to the global state
+// instead. The C++ version was marked const - same as Update, Go has
+// no equivalent keyword and doesn't need one.
+func (sm *StateMachine[T]) HandleMessage(msg Telegram) bool {
+	// first see if the current state is valid and that it can handle
+	// the message
+	if sm.currentState != nil && sm.currentState.OnMessage(sm.owner, msg) {
+		return true
+	}
+
+	// if not, and if a global state has been implemented, send
+	// the message to the global state
+	if sm.globalState != nil && sm.globalState.OnMessage(sm.owner, msg) {
+		return true
+	}
+
+	return false
+}