[packagechooser] Delay initialization of default Id

When the module is loaded and the viewstep created, it doesn't have a
module Id **yet**. That is set after reading more of the configuration
file. It **is** set by the time setConfigurationMap() is called,
so pass it on to the Config object then. This means that packagechooser
modules can skip the *id* config key and use the module Id.

src/modules/packagechooser/Config.cpp

@@ -51,11 +51,10 @@ PackageChooserMethodNames()
     return names;
 }
 
-Config::Config( const Calamares::ModuleSystem::InstanceKey& defaultId, QObject* parent )
+Config::Config( QObject* parent )
     : Calamares::ModuleSystem::Config( parent )
     , m_model( new PackageListModel( this ) )
     , m_mode( PackageChooserMode::Required )
-    , m_defaultId( defaultId )
 {
 }
 
@@ -91,7 +90,7 @@ Config::introductionPackage() const
 void
 Config::updateGlobalStorage( const QStringList& selected ) const
 {
-    QString key = QStringLiteral( "packagechooser_%1" ).arg( m_id );
+    const QString& key = m_id;
     cDebug() << "Writing to GS" << key;
 
     if ( m_method == PackageChooserMethod::Legacy )
@@ -177,24 +176,34 @@ fillModel( PackageListModel* model, const QVariantList& items )
 void
 Config::setConfigurationMap( const QVariantMap& configurationMap )
 {
-    m_mode = packageChooserModeNames().find( CalamaresUtils::getString( configurationMap, "mode" ), PackageChooserMode::Required );
-    m_method = PackageChooserMethodNames().find( CalamaresUtils::getString( configurationMap, "method" ), PackageChooserMethod::Legacy );
+    m_mode = packageChooserModeNames().find( CalamaresUtils::getString( configurationMap, "mode" ),
+                                             PackageChooserMode::Required );
+    m_method = PackageChooserMethodNames().find( CalamaresUtils::getString( configurationMap, "method" ),
+                                                 PackageChooserMethod::Legacy );
 
-    m_id = CalamaresUtils::getString( configurationMap, "id" );
+    {
+        const QString configId = CalamaresUtils::getString( configurationMap, "id" );
+        if ( configId.isEmpty() )
+        {
+            m_id = m_defaultId.toString();
             if ( m_id.isEmpty() )
             {
-        m_id = m_defaultId.id();
+                m_id = QString( "packagechooser" );
+            }
             cDebug() << "Using default ID" << m_id << "from" << m_defaultId.toString();
         }
+        else
+        {
+            m_id = QStringLiteral( "packagechooser_" ) + configId;
+        }
+    }
 
-    m_defaultModelIndex = QModelIndex();
     if ( configurationMap.contains( "items" ) )
     {
         fillModel( m_model, configurationMap.value( "items" ).toList() );
     }
 
     QString default_item_id = CalamaresUtils::getString( configurationMap, "default" );
-    // find default item
     if ( !default_item_id.isEmpty() )
     {
         for ( int item_n = 0; item_n < m_model->packageCount(); ++item_n )

src/modules/packagechooser/Config.h

@@ -40,9 +40,17 @@ class Config : public Calamares::ModuleSystem::Config
     Q_OBJECT
 
 public:
-    Config( const Calamares::ModuleSystem::InstanceKey& defaultId, QObject* parent = nullptr );
+    Config( QObject* parent = nullptr );
     ~Config() override;
 
+    /** @brief Sets the default Id for this Config
+     *
+     * The default Id is the (owning) module identifier for the config,
+     * and it is used when the Id read from the config file is empty.
+     * The **usual** configuration when using method *packages* is
+     * to rely on the default Id.
+     */
+    void setDefaultId( const Calamares::ModuleSystem::InstanceKey& defaultId ) { m_defaultId = defaultId; }
     void setConfigurationMap( const QVariantMap& ) override;
 
     PackageChooserMode mode() const { return m_mode; }

src/modules/packagechooser/PackageChooserViewStep.cpp

@@ -37,7 +37,7 @@ CALAMARES_PLUGIN_FACTORY_DEFINITION( PackageChooserViewStepFactory, registerPlug
 
 PackageChooserViewStep::PackageChooserViewStep( QObject* parent )
     : Calamares::ViewStep( parent )
-    , m_config( new Config( moduleInstanceKey(), this ) )
+    , m_config( new Config( this ) )
     , m_widget( nullptr )
     , m_stepName( nullptr )
 {
@@ -146,6 +146,7 @@ PackageChooserViewStep::jobs() const
 void
 PackageChooserViewStep::setConfigurationMap( const QVariantMap& configurationMap )
 {
+    m_config->setDefaultId( moduleInstanceKey() );
     m_config->setConfigurationMap( configurationMap );
 
     bool labels_ok = false;