From d8d103f6ef686c9d48e51f1888875dd5889c2ac3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rodrigo=20Depin=C3=A9=20Dalpiaz?= <dalpiaze@gmail.com>
Date: Sun, 15 Dec 2024 18:57:45 -0300
Subject: [PATCH] #42 right to left text supporting

---
 Source/Vcl.DHTokenEngine.pas | 14 ++++++++++++--
 Source/Vcl.DzHTMLText.pas    | 16 ++++++++++++++++
 2 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/Source/Vcl.DHTokenEngine.pas b/Source/Vcl.DHTokenEngine.pas
index 7fd6a5a..279be0a 100644
--- a/Source/Vcl.DHTokenEngine.pas
+++ b/Source/Vcl.DHTokenEngine.pas
@@ -480,6 +480,7 @@   TDHBuilder = class
     procedure ProcessSpecificObjects(List: TDHPreVisualItemList);
 
     procedure CheckMissingClosingTags;
+    function GetDefaultHorzTextAlign: TDHHorzAlign;
   public
     constructor Create(Lb: TDzHTMLText; Canvas: TCanvas;
       VisualItems: TDHVisualItemList; ProcBoundsAndLines: TDHProcBoundsAndLines);
@@ -1422,7 +1423,7 @@ procedure TDHToken_Div.Process;
     Props.Offset.Top := 0;
     Props.Offset.Bottom := 0;
     Props.BackColor := clNone;
-    Props.HorzAlign := haLeft;
+    Props.HorzAlign := Builder.GetDefaultHorzTextAlign;
     Props.VertAlign := vaTop;
     Props.LineSpace := 0;
     Props.ParagraphSpace := 0;
@@ -1677,7 +1678,7 @@ constructor TDHBuilder.Create(Lb: TDzHTMLText; Canvas: TCanvas;
   Props.Offset.Bottom := Lb.CalcScale(Lb.Offset.Bottom);
 
   Props.VertAlign := Lb.LineVertAlign;
-  Props.HorzAlign := Lb.LineHorzAlign;
+  Props.HorzAlign := GetDefaultHorzTextAlign;
 
   Props.LineSpace := Lb.CalcScale(Lb.LineSpacing);
   Props.ParagraphSpace := Lb.CalcScale(Lb.ParagraphSpacing);
@@ -1753,6 +1754,12 @@ procedure TDHBuilder.CheckMissingClosingTags;
   end;
 end;
 
+function TDHBuilder.GetDefaultHorzTextAlign: TDHHorzAlign;
+begin
+  Result := Lb.LineHorzAlign;
+  if Lb.RightToLeftText and (Result = haLeft) then Result := haRight;
+end;
+
 procedure TDHBuilder.AddInvalidToken(Position: Integer; const ErrorDescription: string);
 var
   Token: TDHToken_Word;
@@ -2282,6 +2289,9 @@   TFuncAlignResult = record
   end;
 
 begin
+  if Lb.RightToLeftText then
+    Item.Position.X := Line.TextSize.Width - (Item.Position.X + Item.Size.Width);
+
   Check(0, True, Item.HorzAlign);
   Check(1, False, Item.VertAlign);
 
diff --git a/Source/Vcl.DzHTMLText.pas b/Source/Vcl.DzHTMLText.pas
index 99e84db..7db5bc9 100644
--- a/Source/Vcl.DzHTMLText.pas
+++ b/Source/Vcl.DzHTMLText.pas
@@ -377,6 +377,8 @@   TDzHTMLText = class(
 
     FCursor: TCursor;
 
+    FRightToLeftText: Boolean;
+
     UpdatingSemaphore: Integer;
     InternalResizing: Boolean;
 
@@ -435,6 +437,8 @@   TDzHTMLText = class(
     procedure SetParagraphIndent(const Value: TPixels);
     procedure SetCustomStyles(const Value: TDHCustomStyles);
 
+    procedure SetRightToLeftText(const Value: Boolean);
+
     {$IFDEF USE_IMGLST}
     procedure SetImages(const Value: TCustomImageList);
     {$ENDIF}
@@ -644,6 +648,8 @@   TDzHTMLText = class(
     property ParagraphSpacing: TPixels read FParagraphSpacing write SetParagraphSpacing {$IFDEF VCL}default 0{$ENDIF};
     property ParagraphIndent: TPixels read FParagraphIndent write SetParagraphIndent {$IFDEF VCL}default 0{$ENDIF};
 
+    property RightToLeftText: Boolean read FRightToLeftText write SetRightToLeftText default False;
+
     property About: string read FAbout;
   end;
 
@@ -1089,6 +1095,16 @@ procedure TDzHTMLText.SetParagraphIndent(const Value: TPixels);
   end;
 end;
 
+procedure TDzHTMLText.SetRightToLeftText(const Value: Boolean);
+begin
+  if Value<>FRightToLeftText then
+  begin
+    FRightToLeftText := Value;
+
+    BuildAndPaint;
+  end;
+end;
+
 procedure TDzHTMLText.SetListLevelPadding(const Value: TPixels);
 begin
   if Value<>FListLevelPadding then