report definite Agent pre-origin failures to release occupancy

internal/asterisk/call.go

@@ -46,6 +46,18 @@ func NativeCallPhase(err error) string {
 	return "unclassified"
 }
 
+// NativeCallNeverSubmitted is true only when the error occurred before any
+// ARI originate request could have been sent. After submission, even a local
+// error or successful cleanup does not prove the carrier never received SIP.
+func NativeCallNeverSubmitted(err error) bool {
+	switch NativeCallPhase(err) {
+	case "validate", "ari_open", "rtp_listen", "subscribe":
+		return true
+	default:
+		return false
+	}
+}
+
 // NativeCallHTTPStatus extracts a numeric ARI HTTP status without retaining
 // a provider response body, credential or request URL in diagnostic logs.
 func NativeCallHTTPStatus(err error) int {

internal/asterisk/call_test.go

@@ -101,6 +101,19 @@ type nativeHTTPStatusError struct{ code int }
 
 func (e nativeHTTPStatusError) Error() string { return "private ARI response" }
 func (e nativeHTTPStatusError) Code() int     { return e.code }
+func TestOnlyPreSubmitNativeFailureCanBeConfirmedNeverDialed(t *testing.T) {
+	for _, phase := range []string{"validate", "ari_open", "rtp_listen", "subscribe"} {
+		if !NativeCallNeverSubmitted(errors.Join(&NativeCallFailure{Phase: phase, Cause: errors.New("failed")}, errors.New("cleanup"))) {
+			t.Fatalf("%s cannot have created an outbound call", phase)
+		}
+	}
+	for _, phase := range []string{"originate", "answer_wait", "bridge_create", "external_media_create", "unclassified"} {
+		if NativeCallNeverSubmitted(&NativeCallFailure{Phase: phase, Cause: errors.New("unknown")}) {
+			t.Fatalf("%s might have originated", phase)
+		}
+	}
+}
+
 func TestNativeCallFailureReportsStageAndHTTPStatusWithoutResponseBody(t *testing.T) {
 	cause := fmt.Errorf("request failed: %w", nativeHTTPStatusError{code: 404})
 	err := errors.Join(&NativeCallFailure{Phase: "originate", Cause: cause}, errors.New("cleanup failed"))