Allow titleblock vars to be resolved outside the titleblock.

Also implements some variable resolving for Altium imports.

eeschema/sch_plugins/altium/sch_altium_plugin.cpp

@@ -780,8 +780,24 @@ void SCH_ALTIUM_PLUGIN::ParseLabel( const std::map<wxString, wxString>& aPropert
     ASCH_LABEL elem( aProperties );
 
     // TODO: text variable support
+
     if( elem.ownerpartid == ALTIUM_COMPONENT_NONE )
     {
+        if( elem.text == "=SheetNumber" )
+            elem.text = "${#}";
+        else if( elem.text == "=SheetTotal" )
+            elem.text = "${##}";
+        else if( elem.text == "=Title" )
+            elem.text = "${TITLE}";
+        else if( elem.text == "=ProjectRev" )
+            elem.text = "${REVISION}";
+        else if( elem.text == "=Date" )
+            elem.text = "${ISSUE_DATE}";
+        else if( elem.text == "=CompanyName" )
+            elem.text = "${COMPANY}";
+        else if( elem.text == "=DocumentName" )
+            elem.text = "${FILENAME}";
+
         SCH_TEXT* text = new SCH_TEXT( elem.location + m_sheetOffset, elem.text );
 
         SetEdaTextJustification( text, elem.justification );

eeschema/sch_text.cpp

@@ -615,6 +615,12 @@ wxString SCH_TEXT::GetShownText( int aDepth ) const
                 return false;
             };
 
+    std::function<bool( wxString* )> schematicTextResolver =
+            [&]( wxString* token ) -> bool
+            {
+                return Schematic()->ResolveTextVar( token, aDepth + 1 );
+            };
+
     wxString text = EDA_TEXT::GetShownText();
 
     if( text == "~" )   // Legacy placeholder for empty string
@@ -631,7 +637,7 @@ wxString SCH_TEXT::GetShownText( int aDepth ) const
             project = &Schematic()->Prj();
 
         if( aDepth < 10 )
-            text = ExpandTextVars( text, &textResolver, nullptr, project );
+            text = ExpandTextVars( text, &textResolver, &schematicTextResolver, project );
     }
 
     return text;

eeschema/schematic.cpp

@@ -120,6 +120,34 @@ SCH_SCREEN* SCHEMATIC::RootScreen() const
 }
 
 
+bool SCHEMATIC::ResolveTextVar( wxString* token, int aDepth ) const
+{
+    if( token->IsSameAs( wxT( "#" ) ) )
+    {
+        *token = CurrentSheet().GetPageNumber();
+        return true;
+    }
+    else if( token->IsSameAs( wxT( "##" ) ) )
+    {
+        *token = wxString::Format( "%i", Root().CountSheets() );
+        return true;
+    }
+    else if( token->IsSameAs( wxT( "SHEETNAME" ) ) )
+    {
+        *token = CurrentSheet().PathHumanReadable();
+        return true;
+    }
+    else if( token->IsSameAs( wxT( "FILENAME" ) ) )
+    {
+        wxFileName fn( GetFileName() );
+        *token = fn.GetFullName();
+        return true;
+    }
+
+    return CurrentSheet().LastScreen()->GetTitleBlock().TextVarResolver( token, m_project );
+}
+
+
 wxString SCHEMATIC::GetFileName() const
 {
     return IsValid() ? m_rootSheet->GetScreen()->GetFileName() : wxString( wxEmptyString );

eeschema/schematic.h

@@ -113,6 +113,8 @@ public:
     /// Helper to retrieve the screen of the root sheet
     SCH_SCREEN* RootScreen() const;
 
+    bool ResolveTextVar( wxString* token, int aDepth ) const;
+
     /// Helper to retrieve the filename from the root sheet screen
     wxString GetFileName() const override;