From aef698ac1f76c3669f781deea95694bf9bb97e0e Mon Sep 17 00:00:00 2001
From: tznind <tznind@dundee.ac.uk>
Date: Wed, 30 Dec 2020 19:20:43 +0000
Subject: [PATCH] Added unicode symbols option to UICatalog

---
 Terminal.Gui/Views/TreeView.cs            | 10 ++++++----
 UICatalog/Scenarios/TreeViewFileSystem.cs |  3 +++
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/Terminal.Gui/Views/TreeView.cs b/Terminal.Gui/Views/TreeView.cs
index 2551d0747..afca00762 100644
--- a/Terminal.Gui/Views/TreeView.cs
+++ b/Terminal.Gui/Views/TreeView.cs
@@ -3,6 +3,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using NStack;
 
 namespace Terminal.Gui {
 
@@ -892,13 +893,13 @@ namespace Terminal.Gui {
 			string lineBody = tree.AspectGetter(Model);
 
 			// How much space is left after prefix and expansion symbol?
-			var remainingWidth = availableWidth - (prefix.Length + 1 );
+			var remainingWidth = availableWidth - (prefix.Sum(Rune.ColumnWidth) + Rune.ColumnWidth(expansion) );
 
 			// If body of line is too long
-			if(lineBody.Length > remainingWidth)
+			if(lineBody.Sum(l=>Rune.ColumnWidth(l)) > remainingWidth)
 			{
 				// remaining space is zero and truncate the line
-				lineBody = lineBody.Substring(0,remainingWidth);
+				lineBody = new string(lineBody.TakeWhile(c=>(remainingWidth -= Rune.ColumnWidth(c)) > 0).ToArray());
 				remainingWidth = 0;
 			}
 			else{
@@ -909,8 +910,9 @@ namespace Terminal.Gui {
 
 			tree.Move(0,y);
 
-			foreach(Rune r in prefix)
+			foreach(Rune r in prefix){
 				driver.AddRune(r);
+			}
 
 			// pick color for expanded symbol
 			if(tree.Style.ColorExpandSymbol || tree.Style.InvertExpandSymbolColors)
diff --git a/UICatalog/Scenarios/TreeViewFileSystem.cs b/UICatalog/Scenarios/TreeViewFileSystem.cs
index 05de0ad09..1a9526be0 100644
--- a/UICatalog/Scenarios/TreeViewFileSystem.cs
+++ b/UICatalog/Scenarios/TreeViewFileSystem.cs
@@ -29,6 +29,7 @@ namespace UICatalog.Scenarios {
 		private MenuItem miNoSymbols;
 		private MenuItem miColoredSymbols;
 		private MenuItem miInvertSymbols;
+		private MenuItem miUnicodeSymbols;
 		private Terminal.Gui.Attribute green;
 		private Terminal.Gui.Attribute red;
 
@@ -51,6 +52,7 @@ namespace UICatalog.Scenarios {
 					miPlusMinus = new MenuItem ("_PlusMinusSymbols", "", () => SetExpandableSymbols('+','-')){Checked = true, CheckType = MenuItemCheckStyle.Radio},
 					miArrowSymbols = new MenuItem ("_ArrowSymbols", "", () => SetExpandableSymbols('>','v')){Checked = false, CheckType = MenuItemCheckStyle.Radio},
 					miNoSymbols = new MenuItem ("_NoSymbols", "", () => SetExpandableSymbols(null,null)){Checked = false, CheckType = MenuItemCheckStyle.Radio},
+					miUnicodeSymbols = new MenuItem ("_Unicode", "", () => SetExpandableSymbols('ஹ','﷽')){Checked = false, CheckType = MenuItemCheckStyle.Radio},
 					null /*separator*/,
 					miColoredSymbols = new MenuItem ("_ColoredSymbols", "", () => ShowColoredExpandableSymbols()){Checked = false, CheckType = MenuItemCheckStyle.Checked},
 					miInvertSymbols = new MenuItem ("_InvertSymbols", "", () => InvertExpandableSymbols()){Checked = false, CheckType = MenuItemCheckStyle.Checked},
@@ -143,6 +145,7 @@ namespace UICatalog.Scenarios {
 			miPlusMinus.Checked = expand == '+';
 			miArrowSymbols.Checked = expand == '>';
 			miNoSymbols.Checked = expand == null;
+			miUnicodeSymbols.Checked = expand == 'ஹ';
 
 			treeViewNodes.Style.ExpandableSymbol = expand;
 			treeViewNodes.Style.CollapseableSymbol = collapse;