From 4f47233a89e3ab3693dc2be4db604430f135bb4a Mon Sep 17 00:00:00 2001
From: Piotr Warszawski <p.warszawski@gmail.com>
Date: Fri, 4 Sep 2026 21:01:33 +0200
Subject: [PATCH] whois: fall back to the consist owner in the +0/+7 mode too

The +8/+16/+24/+32/+40 (and the new +48) modes all pick the reporting
vehicle the same way: the activator's own Mechanik if it's the primary
driver, otherwise the consist's controlling vehicle (ctOwner) - so the
event still resolves correctly if a wagon happens to trigger it ahead
of its locomotive.

+0 (train name / stations left / stop flag) predates that pattern and
never got it: it required m_activator->Mechanik directly and silently
wrote nothing otherwise. A whois hook placed where the loco doesn't
necessarily lead (e.g. a train that reverses direction, or one being
propelled) can have a wagon trigger the event first and the memcell
stays empty, with no error - hard to diagnose from scenery side.

Same owner-selection, same guard semantics (still nothing written if
neither the activator nor its consist has a controller), only the
source of the vehicle it reads from is widened.
---
 world/Event.cpp | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/world/Event.cpp b/world/Event.cpp
index eb679e72..09afec61 100644
--- a/world/Event.cpp
+++ b/world/Event.cpp
@@ -1129,20 +1129,28 @@ whois_event::run_() {
                 + "[engine power: " + to_string( m_activator->MoverParameters->Power, 2 ) + "]" );
         }
         // +0
-        else if( m_activator->Mechanik ) {
-            if( m_activator->Mechanik->primary() ) { // tylko jeśli ktoś tam siedzi - nie powinno dotyczyć pasażera!
+        else {
+            // same owner selection as the +8/+16/+24/+32/+40/+48 branches above: fall back to
+            // the consist's controlling vehicle if the activator itself isn't one (e.g. a wagon
+            // triggered the event ahead of its locomotive) - +0 used to require the activator's
+            // own Mechanik and silently produce nothing for a wagon-triggered whois
+            auto const *owner { (
+                m_activator->Mechanik != nullptr && m_activator->Mechanik->primary() ?
+                    m_activator->Mechanik :
+                    m_activator->ctOwner ) };
+            if( owner != nullptr ) {
                 targetcell->UpdateValues(
-                    m_activator->Mechanik->TrainName(),
-                    m_activator->Mechanik->StationCount() - m_activator->Mechanik->StationIndex(), // ile przystanków do końca
-                    m_activator->Mechanik->IsStop() ?
+                    owner->TrainName(),
+                    owner->StationCount() - owner->StationIndex(), // ile przystanków do końca
+                    owner->IsStop() ?
                         1 :
                         0, // 1, gdy ma tu zatrzymanie
                     m_input.flags & ( flags::text | flags::value1 | flags::value2 ) );
                 WriteLog(
                     "Type: WhoIs (" + std::to_string( m_input.flags ) + ") - "
-                    + "[train: " + m_activator->Mechanik->TrainName() + "], "
-                    + "[stations left: " + std::to_string( m_activator->Mechanik->StationCount() - m_activator->Mechanik->StationIndex() ) + "], "
-                    + "[stop at next station: " + ( m_activator->Mechanik->IsStop() ? "yes" : "no") + "]" );
+                    + "[train: " + owner->TrainName() + "], "
+                    + "[stations left: " + std::to_string( owner->StationCount() - owner->StationIndex() ) + "], "
+                    + "[stop at next station: " + ( owner->IsStop() ? "yes" : "no") + "]" );
             }
         }
     }