cabana: autocomplete signal names (#27553)

tools/cabana/dbcmanager.cc

@@ -178,6 +178,19 @@ void DBCManager::removeSignal(const MessageId &id, const QString &sig_name) {
   }
 }
 
+QStringList DBCManager::signalNames() {
+  // Used for autocompletion
+  QStringList ret;
+  for (auto const& [_, msg] : msgs) {
+    for (auto sig: msg.getSignals()) {
+      ret << sig->name;
+    }
+  }
+  ret.sort();
+  ret.removeDuplicates();
+  return ret;
+}
+
 DBCManager *dbc() {
   static DBCManager dbc_manager(nullptr);
   return &dbc_manager;

tools/cabana/dbcmanager.h

@@ -30,6 +30,7 @@ public:
     auto it = msgs.find(address);
     return it != msgs.end() ? &it->second : nullptr;
   }
+  QStringList signalNames();
 
 signals:
   void signalAdded(uint32_t address, const cabana::Signal *sig);

tools/cabana/signaledit.cc

@@ -1,6 +1,7 @@
 #include "tools/cabana/signaledit.h"
 
 #include <QApplication>
+#include <QCompleter>
 #include <QDialogButtonBox>
 #include <QHBoxLayout>
 #include <QHeaderView>
@@ -368,6 +369,14 @@ QWidget *SignalItemDelegate::createEditor(QWidget *parent, const QStyleOptionVie
     QLineEdit *e = new QLineEdit(parent);
     e->setFrame(false);
     e->setValidator(index.row() == 0 ? name_validator : double_validator);
+
+    if (item->type == SignalModel::Item::Name) {
+      QCompleter *completer = new QCompleter(dbc()->signalNames());
+      completer->setCaseSensitivity(Qt::CaseInsensitive);
+      completer->setFilterMode(Qt::MatchContains);
+      e->setCompleter(completer);
+    }
+
     return e;
   } else if (item->type == SignalModel::Item::Size) {
     QSpinBox *spin = new QSpinBox(parent);