fix: eating stew

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

@@ -55,9 +55,26 @@ func (s *wifesGlobalState) Execute(e *Elsa) {
 // specifically because she should react to it "when in any state,"
 // same reasoning as why the bathroom-call check above lives in the
 // global state rather than in DoHousework.
+//
+// One guard we added that the book's snippet didn't show: if Bob
+// comes home again while a stew is already in the oven (his fatigue
+// or thirst can send him home more than once before her 1.5-second
+// cooking timer fires), this used to unconditionally call
+// ChangeState(CookStew()) even though she was already IN CookStew.
+// That triggered a pointless Exit-then-Enter round trip on the same
+// state - CookStew.Exit fired (printing "Puttin' the stew on the
+// table" while the stew was still cooking!) and then Enter's
+// "!e.Cooking()" check correctly skipped starting a second stew, so
+// nothing useful happened, just a confusing extra print. Checking
+// Cooking() first avoids the whole misfire.
 func (s *wifesGlobalState) OnMessage(e *Elsa, msg Telegram) bool {
 	switch MessageType(msg.Msg) {
 	case MsgHiHoneyImHome:
+		if e.Cooking() {
+			// already got dinner covered - nothing new to do
+			return true
+		}
+
 		fmt.Printf("\nMessage handled by %s at time: %.5f", GetNameOfEntity(e.ID()), Clock.GetCurrentTime())
 		fmt.Printf("\n%s: Hi honey. Let me make you some of mah fine country stew", GetNameOfEntity(e.ID()))
 		e.FSM().ChangeState(CookStew())