lib_tree_model_adapter.cpp

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/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2017 Chris Pavlina <[email protected]>
 * Copyright (C) 2014 Henner Zeller <[email protected]>
 * Copyright (C) 2023 CERN
 * Copyright (C) 2014-2023 KiCad Developers, see AUTHORS.txt for contributors.
 *
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program. If not, see <http://www.gnu.org/licenses/>.
 */
 
#include <eda_base_frame.h>
#include <eda_pattern_match.h>
#include <kiface_base.h>
#include <kiplatform/ui.h>
#include <lib_tree_model_adapter.h>
#include <project/project_file.h>
#include <settings/app_settings.h>
#include <widgets/ui_common.h>
#include <wx/tokenzr.h>
#include <wx/wupdlock.h>
#include <wx/settings.h>
#include <wx/dc.h>
#include <string_utils.h>
 
 
static const int kDataViewIndent = 20;
 
 
class LIB_TREE_RENDERER : public wxDataViewCustomRenderer
{
public:
 LIB_TREE_RENDERER() :
 m_canvasItem( false )
 {}
 
 wxSize GetSize() const override
 {
 return wxSize( GetOwner()->GetWidth(), GetTextExtent( m_text ).y + 2 );
 }
 
 bool GetValue( wxVariant& aValue ) const override
 {
 aValue = m_text;
 return true;
 }
 
 bool SetValue( const wxVariant& aValue ) override
 {
 m_text = aValue.GetString();
 return true;
 }
 
 void SetAttr( const wxDataViewItemAttr& aAttr ) override
 {
 // Use strikethrough as a proxy for is-canvas-item
 m_canvasItem = aAttr.GetStrikethrough();
 
 wxDataViewItemAttr realAttr = aAttr;
 realAttr.SetStrikethrough( false );
 
 wxDataViewCustomRenderer::SetAttr( realAttr );
 }
 
 bool Render( wxRect aRect, wxDC *dc, int aState ) override
 {
 RenderBackground( dc, aRect );
 
 if( m_canvasItem )
 {
 wxPoint points[6];
 points[0] = aRect.GetTopLeft();
 points[1] = aRect.GetTopRight() + wxPoint( -4, 0 );
 points[2] = aRect.GetTopRight() + wxPoint( 0, aRect.GetHeight() / 2 );
 points[3] = aRect.GetBottomRight() + wxPoint( -4, 1 );
 points[4] = aRect.GetBottomLeft() + wxPoint( 0, 1 );
 points[5] = aRect.GetTopLeft();
 
 dc->SetPen( KIPLATFORM::UI::IsDarkTheme() ? *wxWHITE_PEN : *wxBLACK_PEN );
 dc->DrawLines( 6, points );
 }
 
 aRect.Deflate( 1 );
 
#ifdef __WXOSX__
 // We should be able to pass wxDATAVIEW_CELL_SELECTED into RenderText() and have it do
 // the right thing -- but it picks wxSYS_COLOUR_HIGHLIGHTTEXT on MacOS (instead
 // of wxSYS_COLOUR_LISTBOXHIGHLIGHTTEXT).
 if( aState & wxDATAVIEW_CELL_SELECTED )
 dc->SetTextForeground( wxSystemSettings::GetColour( wxSYS_COLOUR_LISTBOXHIGHLIGHTTEXT ) );
 
 RenderText( m_text, 0, aRect, dc, 0 );
#else
 RenderText( m_text, 0, aRect, dc, aState );
#endif
 return true;
 }
 
private:
 bool m_canvasItem;
 wxString m_text;
};
 
 
wxDataViewItem LIB_TREE_MODEL_ADAPTER::ToItem( const LIB_TREE_NODE* aNode )
{
 return wxDataViewItem( const_cast<void*>( static_cast<void const*>( aNode ) ) );
}
 
 
LIB_TREE_NODE* LIB_TREE_MODEL_ADAPTER::ToNode( wxDataViewItem aItem )
{
 return static_cast<LIB_TREE_NODE*>( aItem.GetID() );
}
 
 
LIB_TREE_MODEL_ADAPTER::LIB_TREE_MODEL_ADAPTER( EDA_BASE_FRAME* aParent,
 const wxString& aPinnedKey ) :
 m_widget( nullptr ),
 m_parent( aParent ),
 m_sort_mode( BEST_MATCH ),
 m_show_units( true ),
 m_preselect_unit( 0 ),
 m_freeze( 0 ),
 m_filter( nullptr )
{
 // Default column widths. Do not translate these names.
 m_colWidths[ _HKI( "Item" ) ] = 300;
 m_colWidths[ _HKI( "Description" ) ] = 600;
 
 m_availableColumns = { _HKI( "Item" ), _HKI( "Description" ) };
 
 APP_SETTINGS_BASE* cfg = Kiface().KifaceSettings();
 
 for( const std::pair<const wxString, int>& pair : cfg->m_LibTree.column_widths )
 m_colWidths[pair.first] = pair.second;
 
 m_shownColumns = cfg->m_LibTree.columns;
 
 if( m_shownColumns.empty() )
 m_shownColumns = { _HKI( "Item" ), _HKI( "Description" ) };
 
 if( m_shownColumns[0] != _HKI( "Item" ) )
 m_shownColumns.insert( m_shownColumns.begin(), _HKI( "Item" ) );
}
 
 
LIB_TREE_MODEL_ADAPTER::~LIB_TREE_MODEL_ADAPTER()
{}
 
 
std::vector<wxString> LIB_TREE_MODEL_ADAPTER::GetOpenLibs() const
{
 std::vector<wxString> openLibs;
 wxDataViewItem rootItem( nullptr );
 wxDataViewItemArray children;
 
 GetChildren( rootItem, children );
 
 for( const wxDataViewItem& child : children )
 {
 if( m_widget->IsExpanded( child ) )
 openLibs.emplace_back( ToNode( child )->m_LibId.GetLibNickname().wx_str() );
 }
 
 return openLibs;
}
 
 
void LIB_TREE_MODEL_ADAPTER::OpenLibs( const std::vector<wxString>& aLibs )
{
 wxWindowUpdateLocker updateLock( m_widget );
 
 for( const wxString& lib : aLibs )
 {
 wxDataViewItem item = FindItem( LIB_ID( lib, wxEmptyString ) );
 
 if( item.IsOk() )
 m_widget->Expand( item );
 }
}
 
 
void LIB_TREE_MODEL_ADAPTER::SaveSettings()
{
 if( m_widget )
 {
 APP_SETTINGS_BASE* cfg = Kiface().KifaceSettings();
 
 cfg->m_LibTree.columns = GetShownColumns();
 cfg->m_LibTree.column_widths.clear();
 
 for( const std::pair<const wxString, wxDataViewColumn*>& pair : m_colNameMap )
 cfg->m_LibTree.column_widths[pair.first] = pair.second->GetWidth();
 
 cfg->m_LibTree.open_libs = GetOpenLibs();
 }
}
 
 
void LIB_TREE_MODEL_ADAPTER::ShowUnits( bool aShow )
{
 m_show_units = aShow;
}
 
 
void LIB_TREE_MODEL_ADAPTER::SetPreselectNode( const LIB_ID& aLibId, int aUnit )
{
 m_preselect_lib_id = aLibId;
 m_preselect_unit = aUnit;
}
 
 
LIB_TREE_NODE_LIBRARY& LIB_TREE_MODEL_ADAPTER::DoAddLibraryNode( const wxString& aNodeName,
 const wxString& aDesc,
 bool pinned )
{
 LIB_TREE_NODE_LIBRARY& lib_node = m_tree.AddLib( aNodeName, aDesc );
 
 lib_node.m_Pinned = pinned;
 
 return lib_node;
}
 
 
void LIB_TREE_MODEL_ADAPTER::DoAddLibrary( const wxString& aNodeName, const wxString& aDesc,
 const std::vector<LIB_TREE_ITEM*>& aItemList,
 bool pinned, bool presorted )
{
 LIB_TREE_NODE_LIBRARY& lib_node = DoAddLibraryNode( aNodeName, aDesc, pinned );
 
 for( LIB_TREE_ITEM* item: aItemList )
 lib_node.AddItem( item );
 
 lib_node.AssignIntrinsicRanks( presorted );
}
 
 
void LIB_TREE_MODEL_ADAPTER::UpdateSearchString( const wxString& aSearch, bool aState )
{
 {
 wxWindowUpdateLocker updateLock( m_widget );
 
 // Even with the updateLock, wxWidgets sometimes ties its knickers in a knot trying to
 // run a wxdataview_selection_changed_callback() on a row that has been deleted.
 // https://bugs.launchpad.net/kicad/+bug/1756255
 m_widget->UnselectAll();
 
 // This collapse is required before the call to "Freeze()" below. Once Freeze()
 // is called, GetParent() will return nullptr. While this works for some calls, it
 // segfaults when we have any expanded elements b/c the sub units in the tree don't
 // have explicit references that are maintained over a search
 // The tree will be expanded again below when we get our matches
 //
 // Also note that this cannot happen when we have deleted a symbol as GTK will also
 // iterate over the tree in this case and find a symbol that has an invalid link
 // and crash https://gitlab.com/kicad/code/kicad/-/issues/6910
 if( !aState && !aSearch.IsNull() && m_tree.m_Children.size() )
 {
 for( std::unique_ptr<LIB_TREE_NODE>& child: m_tree.m_Children )
 m_widget->Collapse( wxDataViewItem( &*child ) );
 }
 
 // DO NOT REMOVE THE FREEZE/THAW. This freeze/thaw is a flag for this model adapter
 // that tells it when it shouldn't trust any of the data in the model. When set, it will
 // not return invalid data to the UI, since this invalid data can cause crashes.
 // This is different than the update locker, which locks the UI aspects only.
 Freeze();
 BeforeReset();
 
 m_tree.ResetScore();
 
 wxStringTokenizer tokenizer( aSearch );
 bool firstTerm = true;
 
 while( tokenizer.HasMoreTokens() )
 {
 // First search for the full token, in case it appears in a search string
 wxString term = tokenizer.GetNextToken().Lower();
 EDA_COMBINED_MATCHER termMatcher( term, CTX_LIBITEM );
 
 m_tree.UpdateScore( &termMatcher, wxEmptyString, firstTerm ? m_filter : nullptr );
 firstTerm = false;
 
 if( term.Contains( ":" ) )
 {
 // Next search for the library:item_name
 wxString lib = term.BeforeFirst( ':' );
 wxString itemName = term.AfterFirst( ':' );
 EDA_COMBINED_MATCHER itemNameMatcher( itemName, CTX_LIBITEM );
 
 m_tree.UpdateScore( &itemNameMatcher, lib, nullptr );
 }
 }
 
 if( firstTerm )
 {
 // No terms processed; just run the filter
 m_tree.UpdateScore( nullptr, wxEmptyString, m_filter );
 }
 
 m_tree.SortNodes( m_sort_mode == BEST_MATCH );
 AfterReset();
 Thaw();
 }
 
 const LIB_TREE_NODE* firstMatch = ShowResults();
 
 if( firstMatch )
 {
 wxDataViewItem item = ToItem( firstMatch );
 m_widget->Select( item );
 
 // Make sure the *parent* item is visible. The selected item is the first (shown) child
 // of the parent. So it's always right below the parent, and this way the user can also
 // see what library the selected part belongs to, without having a case where the selection
 // is off the screen (unless the window is a single row high, which is unlikely).
 //
 // This also happens to circumvent https://bugs.launchpad.net/kicad/+bug/1804400 which
 // appears to be a GTK+3 bug.
 {
 wxDataViewItem parent = GetParent( item );
 
 if( parent.IsOk() )
 m_widget->EnsureVisible( parent );
 }
 
 m_widget->EnsureVisible( item );
 }
}
 
 
void LIB_TREE_MODEL_ADAPTER::AttachTo( wxDataViewCtrl* aDataViewCtrl )
{
 m_widget = aDataViewCtrl;
 aDataViewCtrl->SetIndent( kDataViewIndent );
 aDataViewCtrl->AssociateModel( this );
 recreateColumns();
}
 
 
void LIB_TREE_MODEL_ADAPTER::recreateColumns()
{
 m_widget->ClearColumns();
 
 m_columns.clear();
 m_colIdxMap.clear();
 m_colNameMap.clear();
 
 // The Item column is always shown
 doAddColumn( wxT( "Item" ) );
 
 for( const wxString& colName : m_shownColumns )
 {
 if( !m_colNameMap.count( colName ) )
 doAddColumn( colName, colName == wxT( "Description" ) );
 }
}
 
 
void LIB_TREE_MODEL_ADAPTER::resortTree()
{
 Freeze();
 BeforeReset();
 
 m_tree.SortNodes( m_sort_mode == BEST_MATCH );
 
 AfterReset();
 Thaw();
}
 
 
void LIB_TREE_MODEL_ADAPTER::PinLibrary( LIB_TREE_NODE* aTreeNode )
{
 m_parent->Prj().PinLibrary( aTreeNode->m_LibId.GetLibNickname(), isSymbolModel() );
 aTreeNode->m_Pinned = true;
 
 resortTree();
 m_widget->EnsureVisible( ToItem( aTreeNode ) );
}
 
 
void LIB_TREE_MODEL_ADAPTER::UnpinLibrary( LIB_TREE_NODE* aTreeNode )
{
 m_parent->Prj().UnpinLibrary( aTreeNode->m_LibId.GetLibNickname(), isSymbolModel() );
 aTreeNode->m_Pinned = false;
 
 resortTree();
 // Keep focus at top when unpinning
}
 
 
wxDataViewColumn* LIB_TREE_MODEL_ADAPTER::doAddColumn( const wxString& aHeader, bool aTranslate )
{
 wxString translatedHeader = aTranslate ? wxGetTranslation( aHeader ) : aHeader;
 
 // The extent of the text doesn't take into account the space on either side
 // in the header, so artificially pad it
 wxSize headerMinWidth = KIUI::GetTextSize( translatedHeader + wxT( "MMM" ), m_widget );
 
 if( !m_colWidths.count( aHeader ) || m_colWidths[aHeader] < headerMinWidth.x )
 m_colWidths[aHeader] = headerMinWidth.x;
 
 int index = (int) m_columns.size();
 
 wxDataViewColumn* col = new wxDataViewColumn(
 translatedHeader, new LIB_TREE_RENDERER(), index, m_colWidths[aHeader], wxALIGN_NOT,
 wxDATAVIEW_CELL_INERT | static_cast<int>( wxDATAVIEW_COL_RESIZABLE )
 | static_cast<int>( wxDATAVIEW_COL_SORTABLE ) );
 m_widget->AppendColumn( col );
 
 col->SetMinWidth( headerMinWidth.x );
 
 m_columns.emplace_back( col );
 m_colNameMap[aHeader] = col;
 m_colIdxMap[m_columns.size() - 1] = aHeader;
 
 return col;
}
 
 
void LIB_TREE_MODEL_ADAPTER::addColumnIfNecessary( const wxString& aHeader )
{
 if( m_colNameMap.count( aHeader ) )
 return;
 
 // Columns will be created later
 m_colNameMap[aHeader] = nullptr;
 m_availableColumns.emplace_back( aHeader );
}
 
 
void LIB_TREE_MODEL_ADAPTER::SetShownColumns( const std::vector<wxString>& aColumnNames )
{
 bool recreate = m_shownColumns != aColumnNames;
 
 m_shownColumns = aColumnNames;
 
 if( recreate && m_widget )
 recreateColumns();
}
 
 
LIB_ID LIB_TREE_MODEL_ADAPTER::GetAliasFor( const wxDataViewItem& aSelection ) const
{
 const LIB_TREE_NODE* node = ToNode( aSelection );
 return node ? node->m_LibId : LIB_ID();
}
 
 
int LIB_TREE_MODEL_ADAPTER::GetUnitFor( const wxDataViewItem& aSelection ) const
{
 const LIB_TREE_NODE* node = ToNode( aSelection );
 return node ? node->m_Unit : 0;
}
 
 
LIB_TREE_NODE::TYPE LIB_TREE_MODEL_ADAPTER::GetTypeFor( const wxDataViewItem& aSelection ) const
{
 const LIB_TREE_NODE* node = ToNode( aSelection );
 return node ? node->m_Type : LIB_TREE_NODE::INVALID;
}
 
 
LIB_TREE_NODE* LIB_TREE_MODEL_ADAPTER::GetTreeNodeFor( const wxDataViewItem& aSelection ) const
{
 return ToNode( aSelection );
}
 
 
int LIB_TREE_MODEL_ADAPTER::GetItemCount() const
{
 int n = 0;
 
 for( const std::unique_ptr<LIB_TREE_NODE>& lib: m_tree.m_Children )
 n += lib->m_Children.size();
 
 return n;
}
 
 
wxDataViewItem LIB_TREE_MODEL_ADAPTER::FindItem( const LIB_ID& aLibId )
{
 for( std::unique_ptr<LIB_TREE_NODE>& lib: m_tree.m_Children )
 {
 if( lib->m_Name != aLibId.GetLibNickname().wx_str() )
 continue;
 
 // if part name is not specified, return the library node
 if( aLibId.GetLibItemName() == "" )
 return ToItem( lib.get() );
 
 for( std::unique_ptr<LIB_TREE_NODE>& alias: lib->m_Children )
 {
 if( alias->m_Name == aLibId.GetLibItemName().wx_str() )
 return ToItem( alias.get() );
 }
 
 break; // could not find the part in the requested library
 }
 
 return wxDataViewItem();
}
 
 
wxDataViewItem LIB_TREE_MODEL_ADAPTER::GetCurrentDataViewItem()
{
 return FindItem( m_preselect_lib_id );
}
 
 
unsigned int LIB_TREE_MODEL_ADAPTER::GetChildren( const wxDataViewItem& aItem,
 wxDataViewItemArray& aChildren ) const
{
 const LIB_TREE_NODE* node = ( aItem.IsOk() ? ToNode( aItem ) : &m_tree );
 unsigned int count = 0;
 
 if( node->m_Type == LIB_TREE_NODE::TYPE::ROOT
 || node->m_Type == LIB_TREE_NODE::LIBRARY
 || ( m_show_units && node->m_Type == LIB_TREE_NODE::TYPE::ITEM ) )
 {
 for( std::unique_ptr<LIB_TREE_NODE> const& child: node->m_Children )
 {
 if( child->m_Score > 0 )
 {
 aChildren.Add( ToItem( &*child ) );
 ++count;
 }
 }
 }
 
 return count;
}
 
 
void LIB_TREE_MODEL_ADAPTER::FinishTreeInitialization()
{
 wxDataViewColumn* col = nullptr;
 size_t idx = 0;
 int totalWidth = 0;
 wxString header;
 
 for( ; idx < m_columns.size() - 1; idx++ )
 {
 wxASSERT( m_colIdxMap.count( idx ) );
 
 col = m_columns[idx];
 header = m_colIdxMap[idx];
 
 wxASSERT( m_colWidths.count( header ) );
 
 col->SetWidth( m_colWidths[header] );
 totalWidth += col->GetWidth();
 }
 
 int remainingWidth = m_widget->GetSize().x - totalWidth;
 header = m_columns[idx]->GetTitle();
 
 m_columns[idx]->SetWidth( std::max( m_colWidths[header], remainingWidth ) );
}
 
 
void LIB_TREE_MODEL_ADAPTER::RefreshTree()
{
 // Yes, this is an enormous hack. But it works on all platforms, it doesn't suffer
 // the On^2 sorting issues that ItemChanged() does on OSX, and it doesn't lose the
 // user's scroll position (which re-attaching or deleting/re-inserting columns does).
 static int walk = 1;
 
 std::vector<int> widths;
 
 for( const wxDataViewColumn* col : m_columns )
 widths.emplace_back( col->GetWidth() );
 
 wxASSERT( widths.size() );
 
 // Only use the widths read back if they are non-zero.
 // GTK returns the displayed width of the column, which is not calculated immediately
 if( widths[0] > 0 )
 {
 size_t i = 0;
 
 for( const auto& [ colName, colPtr ] : m_colNameMap )
 m_colWidths[ colName ] = widths[i++];
 }
 
 auto colIt = m_colWidths.begin();
 
 colIt->second += walk;
 colIt++;
 
 if( colIt != m_colWidths.end() )
 colIt->second -= walk;
 
 for( const auto& [ colName, colPtr ] : m_colNameMap )
 {
 if( colPtr == m_columns[0] )
 continue;
 
 wxASSERT( m_colWidths.count( colName ) );
 colPtr->SetWidth( m_colWidths[ colName ] );
 }
 
 walk = -walk;
}
 
 
bool LIB_TREE_MODEL_ADAPTER::HasContainerColumns( const wxDataViewItem& aItem ) const
{
 return IsContainer( aItem );
}
 
 
bool LIB_TREE_MODEL_ADAPTER::IsContainer( const wxDataViewItem& aItem ) const
{
 LIB_TREE_NODE* node = ToNode( aItem );
 return node ? node->m_Children.size() : true;
}
 
 
wxDataViewItem LIB_TREE_MODEL_ADAPTER::GetParent( const wxDataViewItem& aItem ) const
{
 if( m_freeze )
 return ToItem( nullptr );
 
 LIB_TREE_NODE* node = ToNode( aItem );
 LIB_TREE_NODE* parent = node ? node->m_Parent : nullptr;
 
 // wxDataViewModel has no root node, but rather top-level elements have
 // an invalid (null) parent.
 if( !node || !parent || parent->m_Type == LIB_TREE_NODE::TYPE::ROOT )
 return ToItem( nullptr );
 else
 return ToItem( parent );
}
 
 
void LIB_TREE_MODEL_ADAPTER::GetValue( wxVariant& aVariant,
 const wxDataViewItem& aItem,
 unsigned int aCol ) const
{
 if( IsFrozen() )
 {
 aVariant = wxEmptyString;
 return;
 }
 
 LIB_TREE_NODE* node = ToNode( aItem );
 wxCHECK( node, /* void */ );
 wxString valueStr;
 
 switch( aCol )
 {
 case NAME_COL:
 if( node->m_Pinned )
 valueStr = GetPinningSymbol() + UnescapeString( node->m_Name );
 else
 valueStr = UnescapeString( node->m_Name );
 
 break;
 
 default:
 if( m_colIdxMap.count( aCol ) )
 {
 const wxString& key = m_colIdxMap.at( aCol );
 
 if( key == wxT( "Description" ) )
 valueStr = UnescapeString( node->m_Desc );
 else if( node->m_Fields.count( key ) )
 valueStr = UnescapeString( node->m_Fields.at( key ) );
 else
 valueStr = wxEmptyString;
 }
 
 break;
 }
 
 valueStr.Replace( wxS( "\n" ), wxS( " " ) ); // Clear line breaks
 
 aVariant = valueStr;
}
 
 
bool LIB_TREE_MODEL_ADAPTER::GetAttr( const wxDataViewItem& aItem,
 unsigned int aCol,
 wxDataViewItemAttr& aAttr ) const
{
 if( IsFrozen() )
 return false;
 
 LIB_TREE_NODE* node = ToNode( aItem );
 wxCHECK( node, false );
 
 if( node->m_Type == LIB_TREE_NODE::ITEM )
 {
 if( !node->m_IsRoot && aCol == 0 )
 {
 // Names of non-root aliases are italicized
 aAttr.SetItalic( true );
 return true;
 }
 }
 
 return false;
}
 
 
void recursiveDescent( LIB_TREE_NODE& aNode, const std::function<int( const LIB_TREE_NODE* )>& f )
{
 for( std::unique_ptr<LIB_TREE_NODE>& node: aNode.m_Children )
 {
 int r = f( node.get() );
 
 if( r == 0 )
 break;
 else if( r == -1 )
 continue;
 
 recursiveDescent( *node, f );
 }
}
 
 
const LIB_TREE_NODE* LIB_TREE_MODEL_ADAPTER::ShowResults()
{
 const LIB_TREE_NODE* firstMatch = nullptr;
 
 // Expand parents of leaf nodes with some level of matching
 recursiveDescent( m_tree,
 [&]( const LIB_TREE_NODE* n )
 {
 if( n->m_Type == LIB_TREE_NODE::TYPE::ITEM && n->m_Score > 1 )
 {
 if( !firstMatch )
 firstMatch = n;
 else if( n->m_Score > firstMatch->m_Score )
 firstMatch = n;
 
 m_widget->ExpandAncestors( ToItem( n ) );
 }
 
 return 1; // keep going to expand ancestors of all found items
 } );
 
 // If no matches, find and show the preselect node
 if( !firstMatch && m_preselect_lib_id.IsValid() )
 {
 recursiveDescent( m_tree,
 [&]( const LIB_TREE_NODE* n )
 {
 // Don't match the recent and already placed libraries
 if( n->m_Name.StartsWith( "-- " ) )
 return -1; // Skip this node and its children
 
 if( n->m_Type == LIB_TREE_NODE::ITEM
 && ( n->m_Children.empty() || !m_preselect_unit )
 && m_preselect_lib_id == n->m_LibId )
 {
 firstMatch = n;
 m_widget->ExpandAncestors( ToItem( n ) );
 return 0;
 }
 else if( n->m_Type == LIB_TREE_NODE::UNIT
 && ( m_preselect_unit && m_preselect_unit == n->m_Unit )
 && m_preselect_lib_id == n->m_Parent->m_LibId )
 {
 firstMatch = n;
 m_widget->ExpandAncestors( ToItem( n ) );
 return 0;
 }
 
 return 1;
 } );
 }
 
 // If still no matches expand a single library if there is only one
 if( !firstMatch )
 {
 int libraries = 0;
 
 for( const std::unique_ptr<LIB_TREE_NODE>& child : m_tree.m_Children )
 {
 if( !child->m_Name.StartsWith( "-- " ) )
 libraries++;
 }
 
 if( libraries != 1 )
 return nullptr;
 
 recursiveDescent( m_tree,
 [&]( const LIB_TREE_NODE* n )
 {
 if( n->m_Type == LIB_TREE_NODE::TYPE::ITEM )
 {
 firstMatch = n;
 m_widget->ExpandAncestors( ToItem( n ) );
 return 0;
 }
 
 return 1;
 } );
 }
 
 return firstMatch;
}