Update Page Number when Duplicating or Pasting sheets

Fixes https://gitlab.com/kicad/code/kicad/-/issues/7872

Also, update hierarchy before renaming pasted sheets
Avoids duplicate sheet names when pasting multiple sheets

eeschema/sch_sheet_path.cpp

@@ -482,8 +482,8 @@ void SCH_SHEET_LIST::BuildSheetList( SCH_SHEET* aSheet, bool aCheckIntegrity )
 
 void SCH_SHEET_LIST::SortByPageNumbers( bool aUpdateVirtualPageNums )
 {
-    std::sort( begin(), end(), 
+    std::sort( begin(), end(),
-        []( SCH_SHEET_PATH a, SCH_SHEET_PATH b ) -> bool 
+        []( SCH_SHEET_PATH a, SCH_SHEET_PATH b ) -> bool
         {
             wxString pageA = a.GetPageNumber();
             wxString pageB = b.GetPageNumber();
@@ -515,6 +515,18 @@ bool SCH_SHEET_LIST::NameExists( const wxString& aSheetName ) const
 }
 
 
+bool SCH_SHEET_LIST::PageNumberExists( const wxString& aPageNumber ) const
+{
+    for( const SCH_SHEET_PATH& sheet : *this )
+    {
+        if( sheet.Last()->GetPageNumber( sheet ) == aPageNumber )
+            return true;
+    }
+
+    return false;
+}
+
+
 bool SCH_SHEET_LIST::IsModified() const
 {
     for( const SCH_SHEET_PATH& sheet : *this )

eeschema/sch_sheet_path.h

@@ -457,6 +457,8 @@ public:
 
     bool NameExists( const wxString& aSheetName ) const;
 
+    bool PageNumberExists( const wxString& aPageNumber ) const;
+
     /**
      * Update all of the symbol instance information using \a aSymbolInstances.
      * WARNING: Do not call this on anything other than the full hierarchy.

eeschema/tools/sch_edit_tool.cpp

@@ -861,6 +861,17 @@ int SCH_EDIT_TOOL::Duplicate( const TOOL_EVENT& aEvent )
             nameField.SetText( candidateName );
 
             sheet->SetParent( m_frame->GetCurrentSheet().Last() );
+
+            SCH_SHEET_PATH sheetpath = m_frame->GetCurrentSheet();
+            sheetpath.push_back( sheet );
+            int page = 1;
+            wxString pageNum = wxString::Format( "%d", page );
+
+            while( hierarchy.PageNumberExists( pageNum ) )
+                pageNum = wxString::Format( "%d", ++page );
+
+            sheet->AddInstance( sheetpath.Path() );
+            sheet->SetPageNumber( sheetpath, pageNum );
             m_frame->AddToScreen( sheet, m_frame->GetScreen() );
 
             copiedSheets = true;

eeschema/tools/sch_editor_control.cpp

@@ -1485,6 +1485,10 @@ int SCH_EDITOR_CONTROL::Paste( const TOOL_EVENT& aEvent )
 
             int uniquifier = std::max( 0, wxAtoi( number ) ) + 1;
 
+            // Ensure we have latest hierarchy, as we may have added a sheet in the previous
+            // iteration
+            hierarchy = m_frame->Schematic().GetSheets();
+
             while( hierarchy.NameExists( candidateName ) )
                 candidateName = wxString::Format( wxT( "%s%d" ), baseName, uniquifier++ );
 
@@ -1531,7 +1535,14 @@ int SCH_EDITOR_CONTROL::Paste( const TOOL_EVENT& aEvent )
             SCH_SHEET_PATH pastePath = pasteRoot;
             pastePath.push_back( sheet );
 
+            int      page = 1;
+            wxString pageNum = wxString::Format( "%d", page );
+
+            while( hierarchy.PageNumberExists( pageNum ) )
+                pageNum = wxString::Format( "%d", ++page );
+
             sheet->AddInstance( pastePath.Path() );
+            sheet->SetPageNumber( pastePath, pageNum );
             updatePastedInstances( pastePath, clipPath, sheet, forceKeepAnnotations );
         }