Adding subscript support (no rendering)

FC.MathEditor/WpfMathEditor/Classes/Helpers/ExportHelper.vb

@@ -175,7 +175,13 @@
     Protected MustOverride ReadOnly Property PreferInlineContent_Internal As Boolean
     Public ReadOnly Property PreferInlineContent As Boolean
         Get
-            Return PreferInlineContent_Internal ' OrElse (This.ParentElement IsNot Nothing AndAlso This.ParentElement.Export.PreferInlineContent)
+            Return PreferInlineContent_Internal OrElse (This.ParentElement IsNot Nothing AndAlso This.ParentElement.Export.PreferInlineContentFor(This))
+        End Get
+    End Property
+
+    Public Overridable ReadOnly Property PreferInlineContentFor(Child As MathElement) As Boolean
+        Get
+            Return PreferInlineContent
         End Get
     End Property
 

FC.MathEditor/WpfMathEditor/Classes/Helpers/InputHelper.vb

@@ -91,7 +91,20 @@
     End Function
 
     Public Function ProcessChar_FromRight(InputChar As Integer) As Boolean
+
+        ' Process special chars from right
+        Select Case InputChar
+            Case AscW("_"c)
+                If ProcessUnderscore_FromRight() Then Return True
+            Case AscW("/"c)
+                If ProcessFraction_FromRight() Then Return True
+            Case AscW("^"c)
+                If ProcessHat_FromRight() Then Return True
+        End Select
+
+        ' Handle all other cases
         Return ProcessChar_FromRight_Internal(InputChar)
+
     End Function
 
     Public Sub ProcessDelete(Ctrl As Boolean, Alt As Boolean, Shift As Boolean)
@@ -104,23 +117,22 @@
                 Exit Sub
             End If
 
+            ' Perform the classical action for Delete for this element
+            If ProcessDelete_Internal(Ctrl, Alt, Shift) Then
+                Exit Sub
+            End If
+
+            ' If this element didn't respond to the keypress, we may forward the event to another one
+            If This.Selection.NextSibling Is Nothing Then
+                If This.Selection.MoveAfterParent() Then This.Selection.ParentElement.Input.ProcessDelete(Ctrl, Alt, Shift)
+                Exit Sub
+            End If
+
         Else
 
             ' If the selection is not empty, we just need to delete its content
             This.Selection.DeleteContents()
-            Exit Sub
-
-        End If
-
-        ' Perform the classical action for Delete for this element
-        If ProcessDelete_Internal(Ctrl, Alt, Shift) Then
-            Exit Sub
-        End If
 
-        ' If this element didn't respond to the keypress, we may forward the event to another one
-        If This.Selection.NextSibling Is Nothing Then
-            If This.Selection.MoveAfterParent() Then This.Selection.ParentElement.Input.ProcessDelete(Ctrl, Alt, Shift)
-            Exit Sub
         End If
 
     End Sub
@@ -299,7 +311,7 @@
 
     Public Overridable Function ProcessWaitChar(InputChar As Integer) As Boolean
         ' Default wait char processing : eat, and walk to next child
-        WaitChar = Nothing : This.Selection.SetPoint(This.ParentElement.GetSelectionAt(This.ChildIndex + 1))
+        WaitChar = Nothing : This.Selection.SetPoint(This.ParentElement.GetSelectionAfter())
         Return True
     End Function
 
@@ -335,10 +347,9 @@
         ' In case there's no element to delete, forward the call
         If ElementToDelete Is Nothing Then Return False
 
-        ' If there's one element to delete, delete it
+        ' Move selection end point to the right, then clear
         ProcessRightKey(Ctrl, Alt, True)
         This.Selection.DeleteContents()
-        'x ElementToDelete.ParentElement.RemoveChild(ElementToDelete)
 
         ' Inform that the delete key was handled
         Return True
@@ -353,10 +364,9 @@
         ' In case there's no element to delete, forward the call
         If ElementToDelete Is Nothing Then Return False
 
-        ' If there's one element to delete, delete it
+        ' Move selection end point to the left, then clear
         ProcessLeftKey(Ctrl, Alt, True)
         This.Selection.DeleteContents()
-        'x ElementToDelete.ParentElement.RemoveChild(ElementToDelete)
 
         ' Inform that the delete key was handled
         Return True
@@ -443,19 +453,50 @@
         Return False
     End Function
 
+    ' TODO: Override this for RLE to avoid RLE in RLE (+next functions)
     Public Overridable Function ProcessHat_FromRight_Internal() As Boolean
-        ' TODO: ProcessHat
+
+        ' Wrap the element in a script automatically by default
+        Dim Script As New SubSupScriptFormatter()
+        This.ParentElement.ReplaceChild(This, Script)
+        Script.Base.AddChild(This)
+
+        ' Set the selection in the script
+        This.Selection.SetPoint(Script.SuperScript.GetSelectionAtOrigin())
+
+        ' Abort any other steps
         Return True
+
     End Function
 
     Public Overridable Function ProcessUnderscore_FromRight_Internal() As Boolean
-        ' TODO: ProcessUnderscore
+
+        ' Wrap the element in a script automatically by default
+        Dim Script As New SubSupScriptFormatter()
+        This.ParentElement.ReplaceChild(This, Script)
+        Script.Base.AddChild(This)
+
+        ' Set the selection in the script
+        This.Selection.SetPoint(Script.SubScript.GetSelectionAtOrigin())
+
+        ' Abort any other steps
         Return True
+
     End Function
 
     Public Overridable Function ProcessFraction_FromRight_Internal() As Boolean
-        ' TODO: ProcessFraction
+
+        ' Wrap the element in a fraction automatically by default
+        Dim Fraction As New FractionFormatter()
+        This.ParentElement.ReplaceChild(This, Fraction)
+        Fraction.Numerator.AddChild(This)
+
+        ' Set the selection in the script
+        This.Selection.SetPoint(Fraction.Denominator.GetSelectionAtOrigin())
+
+        ' Abort any other steps
         Return True
+
     End Function
 
     Public Event BeforeProcessChar As EventHandler(Of InputEventArgs)

FC.MathEditor/WpfMathEditor/EquationEditor.vbproj

@@ -120,6 +120,8 @@
     <Compile Include="Formatters\Fraction\FractionFormatterExportHelper.vb" />
     <Compile Include="Formatters\Root\RootFormatter.vb" />
     <Compile Include="Formatters\Root\RootFormatterExportHelper.vb" />
+    <Compile Include="Formatters\SubSupScript\SubSupScriptFormatter.vb" />
+    <Compile Include="Formatters\SubSupScript\SubSupScriptFormatterExportHelper.vb" />
     <Compile Include="QualityControl.vb" />
     <Compile Include="Classes\Helpers\SelectionHelper2.Actions.vb" />
     <Compile Include="Classes\Helpers\SelectionHelper2.SubTypes.vb" />
@@ -234,7 +236,6 @@
   </ItemGroup>
   <ItemGroup>
     <Folder Include="Classes\Properties\" />
-    <Folder Include="Formatters\SubScript\" />
     <Folder Include="Parsers\Elements\" />
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.VisualBasic.targets" />

FC.MathEditor/WpfMathEditor/Formatters/Fraction/FractionFormatter.vb

@@ -1,6 +1,5 @@
 Public Class FractionFormatter : Inherits MathElement
 
-
     Public Sub New(Optional Numerator As RowLayoutEngine = Nothing, Optional Denominator As RowLayoutEngine = Nothing)
 
         If Numerator Is Nothing Then Numerator = New RowLayoutEngine()

FC.MathEditor/WpfMathEditor/Formatters/SubSupScript/SubSupScriptFormatter.vb

@@ -0,0 +1,68 @@
+Public Class SubSupScriptFormatter : Inherits MathElement
+
+    Public Sub New(Optional Base As RowLayoutEngine = Nothing, Optional SubScript As RowLayoutEngine = Nothing, Optional SuperScript As RowLayoutEngine = Nothing)
+
+        If Base Is Nothing Then Base = New RowLayoutEngine()
+        If SubScript Is Nothing Then SubScript = New RowLayoutEngine()
+        If SuperScript Is Nothing Then SuperScript = New RowLayoutEngine()
+
+        Children.Add(Base)
+        Children.Add(SubScript)
+        Children.Add(SuperScript)
+        DirectCast(Children, FormatterChildrenHelper).Freeze()
+
+    End Sub
+
+    Public Property Base As RowLayoutEngine
+        Get
+            Return Children(0)
+        End Get
+        Set(value As RowLayoutEngine)
+            Children.Replace(Children(0), value)
+        End Set
+    End Property
+
+    Public Property SubScript As RowLayoutEngine
+        Get
+            Return Children(1)
+        End Get
+        Set(value As RowLayoutEngine)
+            Children.Replace(Children(1), value)
+        End Set
+    End Property
+
+    Public Property SuperScript As RowLayoutEngine
+        Get
+            Return Children(2)
+        End Get
+        Set(value As RowLayoutEngine)
+            Children.Replace(Children(2), value)
+        End Set
+    End Property
+
+    Protected Overrides Function Clone_Internal(ByRef ShouldCloneChildren As Boolean) As MathElement
+
+        If ShouldCloneChildren Then
+            Dim Result As New SubSupScriptFormatter(Base.Clone, SubScript.Clone, SuperScript.Clone)
+            ShouldCloneChildren = False
+            Return Result
+        Else
+            Return New SubSupScriptFormatter()
+        End If
+
+    End Function
+
+    Protected Overrides Function GetInitialChildrenHelper() As ChildrenHelper
+        Return New FormatterChildrenHelper(Me)
+    End Function
+
+    Protected Overrides Function GetInitialExportHelper() As ExportHelper
+        Return New SubSupScriptFormatterExportHelper(Me)
+    End Function
+
+    Protected Overrides Function GetInitialInputHelper() As InputHelper
+        ' TODO: Input helper for
+        Return New EmptyInputHelper(Me)
+    End Function
+
+End Class

FC.MathEditor/WpfMathEditor/Formatters/SubSupScript/SubSupScriptFormatterExportHelper.vb

@@ -0,0 +1,68 @@
+Public Class SubSupScriptFormatterExportHelper : Inherits ExportHelper
+
+    Public Sub New(This As SubSupScriptFormatter)
+        MyBase.New(This)
+    End Sub
+
+    Public Shadows ReadOnly Property This As SubSupScriptFormatter
+        Get
+            Return MyBase.This
+        End Get
+    End Property
+
+    Public Overrides Sub AppendKeyboardInput(SB As System.Text.StringBuilder)
+        This.Base.Export.AppendKeyboardInput(SB)
+        SB.Append("_"c)
+        This.SubScript.Export.AppendKeyboardInput(SB)
+    End Sub
+
+    Public Overrides Sub AppendLaTeX(SB As System.Text.StringBuilder)
+        This.Base.Export.AppendLaTeX(SB)
+        SB.Append("_"c)
+        This.SubScript.Export.AppendLaTeX(SB)
+    End Sub
+
+    Public Overrides Sub AppendMathML(SB As System.Text.StringBuilder)
+
+    End Sub
+
+    Public Overrides Sub AppendSimpleText(SB As System.Text.StringBuilder)
+        This.Base.Export.AppendSimpleText(SB)
+        SB.Append("_"c)
+        This.SubScript.Export.AppendSimpleText(SB)
+    End Sub
+
+    Protected Overrides Sub CalculateMinHeight_Internal()
+
+    End Sub
+
+    Protected Overrides Sub Draw_Internal(DG As System.Windows.Media.DrawingContext)
+
+    End Sub
+
+    Protected Overrides Sub GenerateLayout_Internal()
+
+    End Sub
+
+    Protected Overrides ReadOnly Property PreferInlineContent_Internal As Boolean
+        Get
+            Return False
+        End Get
+    End Property
+
+    Public Overrides ReadOnly Property PreferInlineContentFor(Child As MathElement) As Boolean
+        Get
+
+            ' Only the scripts have a special behavior
+            If Child IsNot This.Base Then Return True
+
+            ' We need to keep inheritance for the base
+            Return MyBase.PreferInlineContentFor(Child)
+
+        End Get
+    End Property
+
+    Protected Overrides Sub PrepareLayout_Internal(AvailABH As Double, AvailBBH As Double)
+
+    End Sub
+End Class

FC.MathEditor/WpfMathEditor/LayoutEngines/Row/RowLayoutEngineExportHelper.vb

@@ -6,25 +6,57 @@ Public Class RowLayoutEngineExportHelper : Inherits ExportHelper
     End Sub
 
     Public Overrides Sub AppendSimpleText(SB As System.Text.StringBuilder)
-        For Each Child In This.Children
-            Child.Export.AppendSimpleText(SB)
-        Next
+        If This.Children.HasOne AndAlso This.Children.First.IsTextEdit Then
+
+            ' If there's only one child and that it's text, we can simply add it
+            This.Children.First.Export.AppendSimpleText(SB)
+
+        Else
+
+            ' Or else we need parenthesis
+            SB.Append("("c)
+            For Each Child In This.Children
+                Child.Export.AppendSimpleText(SB)
+            Next
+            SB.Append(")"c)
+
+        End If
     End Sub
 
     Public Overrides Sub AppendKeyboardInput(SB As System.Text.StringBuilder)
-        SB.Append("(")
-        For Each Child In This.Children
-            Child.Export.AppendKeyboardInput(SB)
-        Next
-        SB.Append(")")
+        If This.Children.HasOne AndAlso This.Children.First.IsTextEdit Then
+
+            ' If there's only one child and that it's text, we can simply add it
+            This.Children.First.Export.AppendKeyboardInput(SB)
+
+        Else
+
+            ' Or else we need parenthesis
+            SB.Append("("c)
+            For Each Child In This.Children
+                Child.Export.AppendKeyboardInput(SB)
+            Next
+            SB.Append(")"c)
+
+        End If
     End Sub
 
     Public Overrides Sub AppendLaTeX(SB As System.Text.StringBuilder)
-        SB.Append("{")
-        For Each Child In This.Children
-            Child.Export.AppendLaTeX(SB)
-        Next
-        SB.Append("}")
+        If This.Children.HasOne AndAlso This.Children.First.IsTextEdit Then
+
+            ' If there's only one child and that it's text, we can simply add it
+            This.Children.First.Export.AppendLaTeX(SB)
+
+        Else
+
+            ' Or else we need parenthesis
+            SB.Append("{")
+            For Each Child In This.Children
+                Child.Export.AppendLaTeX(SB)
+            Next
+            SB.Append("}")
+
+        End If
     End Sub
 
     Public Overrides Sub AppendMathML(SB As System.Text.StringBuilder)