Improve word count: real-time updates, better perf, and formatted display

src/Notepads/Controls/TextEditor/ITextEditor.cs

@@ -1,4 +1,4 @@
-// ---------------------------------------------------------------------------------------------
+// ---------------------------------------------------------------------------------------------
 //  Copyright (c) 2019-2024, Jiaqi (0x7c13) Liu. All rights reserved.
 //  See LICENSE file in the project root for license information.
 // ---------------------------------------------------------------------------------------------
@@ -74,6 +74,8 @@ void Init(TextFile textFile,
 
         string GetText();
 
+        string GetSelectedText();
+
         void StartCheckingFileStatusPeriodically();
 
         void StopCheckingFileStatus();

src/Notepads/Controls/TextEditor/TextEditor.xaml.cs

@@ -1,4 +1,4 @@
-namespace Notepads.Controls.TextEditor
+namespace Notepads.Controls.TextEditor
 {
     using System;
     using System.Collections.Generic;
@@ -312,6 +312,13 @@ public string GetText()
             return TextEditorCore.GetText();
         }
 
+        public string GetSelectedText()
+        {
+            return TextEditorCore.Document.Selection.StartPosition == TextEditorCore.Document.Selection.EndPosition
+                ? string.Empty
+                : TextEditorCore.Document.Selection.Text;
+        }
+
         // Make sure this method is thread safe
         public TextEditorStateMetaData GetTextEditorStateMetaData()
         {

src/Notepads/Core/INotepadsCore.cs

@@ -1,4 +1,4 @@
-// ---------------------------------------------------------------------------------------------
+// ---------------------------------------------------------------------------------------------
 //  Copyright (c) 2019-2024, Jiaqi (0x7c13) Liu. All rights reserved.
 //  See LICENSE file in the project root for license information.
 // ---------------------------------------------------------------------------------------------
@@ -31,6 +31,7 @@ public interface INotepadsCore
         event EventHandler<ITextEditor> TextEditorFontZoomFactorChanged;
         event EventHandler<ITextEditor> TextEditorEncodingChanged;
         event EventHandler<ITextEditor> TextEditorLineEndingChanged;
+        event EventHandler<ITextEditor> TextEditorTextChanging;
         event EventHandler<ITextEditor> TextEditorModeChanged;
         event EventHandler<ITextEditor> TextEditorMovedToAnotherAppInstance;
         event EventHandler<IReadOnlyList<IStorageItem>> StorageItemsDropped;

src/Notepads/Core/NotepadsCore.cs

@@ -1,4 +1,4 @@
-// ---------------------------------------------------------------------------------------------
+// ---------------------------------------------------------------------------------------------
 //  Copyright (c) 2019-2024, Jiaqi (0x7c13) Liu. All rights reserved.
 //  See LICENSE file in the project root for license information.
 // ---------------------------------------------------------------------------------------------
@@ -42,6 +42,7 @@ public class NotepadsCore : INotepadsCore
         public event EventHandler<ITextEditor> TextEditorFontZoomFactorChanged;
         public event EventHandler<ITextEditor> TextEditorEncodingChanged;
         public event EventHandler<ITextEditor> TextEditorLineEndingChanged;
+        public event EventHandler<ITextEditor> TextEditorTextChanging;
         public event EventHandler<ITextEditor> TextEditorModeChanged;
         public event EventHandler<ITextEditor> TextEditorMovedToAnotherAppInstance;
         public event EventHandler<IReadOnlyList<IStorageItem>> StorageItemsDropped;
@@ -199,6 +200,7 @@ public ITextEditor CreateTextEditor(
             textEditor.Loaded += TextEditor_Loaded;
             textEditor.Unloaded += TextEditor_Unloaded;
             textEditor.SelectionChanged += TextEditor_OnSelectionChanged;
+            textEditor.TextChanging += TextEditor_OnTextChanging;
             textEditor.FontZoomFactorChanged += TextEditor_OnFontZoomFactorChanged;
             textEditor.KeyDown += TextEditorKeyDown;
             textEditor.ModificationStateChanged += TextEditor_OnEditorModificationStateChanged;
@@ -238,6 +240,7 @@ public void DeleteTextEditor(ITextEditor textEditor)
             textEditor.Unloaded -= TextEditor_Unloaded;
             textEditor.KeyDown -= TextEditorKeyDown;
             textEditor.SelectionChanged -= TextEditor_OnSelectionChanged;
+            textEditor.TextChanging -= TextEditor_OnTextChanging;
             textEditor.FontZoomFactorChanged -= TextEditor_OnFontZoomFactorChanged;
             textEditor.ModificationStateChanged -= TextEditor_OnEditorModificationStateChanged;
             textEditor.ModeChanged -= TextEditor_OnModeChanged;
@@ -521,6 +524,12 @@ private void TextEditor_OnSelectionChanged(object sender, EventArgs e)
             TextEditorSelectionChanged?.Invoke(this, textEditor);
         }
 
+        private void TextEditor_OnTextChanging(object sender, EventArgs e)
+        {
+            if (!(sender is ITextEditor textEditor)) return;
+            TextEditorTextChanging?.Invoke(this, textEditor);
+        }
+
         private void TextEditor_OnFontZoomFactorChanged(object sender, EventArgs e)
         {
             if (!(sender is ITextEditor textEditor)) return;

src/Notepads/Views/MainPage/NotepadsMainPage.StatusBar.cs

@@ -1,4 +1,4 @@
-// ---------------------------------------------------------------------------------------------
+// ---------------------------------------------------------------------------------------------
 //  Copyright (c) 2019-2024, Jiaqi (0x7c13) Liu. All rights reserved.
 //  See LICENSE file in the project root for license information.
 // ---------------------------------------------------------------------------------------------
@@ -40,6 +40,7 @@ private void SetupStatusBar(ITextEditor textEditor)
             UpdatePathIndicator(textEditor);
             UpdateEditorModificationIndicator(textEditor);
             UpdateLineColumnIndicator(textEditor);
+            UpdateWordCountIndicator(textEditor);
             UpdateFontZoomIndicator(textEditor);
             UpdateLineEndingIndicator(textEditor.GetLineEnding());
             UpdateEncodingIndicator(textEditor.GetEncoding());
@@ -161,6 +162,65 @@ private void UpdateLineColumnIndicator(ITextEditor textEditor)
                     selectedCount, wordSelected);
         }
 
+        private void UpdateWordCountIndicator(ITextEditor textEditor)
+        {
+            if (StatusBar == null) return;
+
+            var fullText = textEditor.GetText();
+            var totalWordCount = CountWords(fullText);
+
+            var selectedText = textEditor.GetSelectedText();
+            if (!string.IsNullOrEmpty(selectedText))
+            {
+                var selectedWordCount = CountWords(selectedText);
+                WordCountIndicator.Text = string.Format(
+                    "Words: {0} | Selected: {1}",
+                    totalWordCount.ToString("N0", CultureInfo.CurrentCulture),
+                    selectedWordCount.ToString("N0", CultureInfo.CurrentCulture));
+            }
+            else
+            {
+                WordCountIndicator.Text = string.Format(
+                    "Words: {0}",
+                    totalWordCount.ToString("N0", CultureInfo.CurrentCulture));
+            }
+        }
+
+        /// <summary>
+        /// Counts words in the given text using character iteration for efficiency.
+        /// A word is defined as a contiguous sequence of non-whitespace characters.
+        /// </summary>
+        private static int CountWords(string text)
+        {
+            if (string.IsNullOrEmpty(text)) return 0;
+
+            int wordCount = 0;
+            bool inWord = false;
+
+            for (int i = 0; i < text.Length; i++)
+            {
+                if (char.IsWhiteSpace(text[i]))
+                {
+                    if (inWord)
+                    {
+                        wordCount++;
+                        inWord = false;
+                    }
+                }
+                else
+                {
+                    inWord = true;
+                }
+            }
+
+            if (inWord)
+            {
+                wordCount++;
+            }
+
+            return wordCount;
+        }
+
         private void UpdateFontZoomIndicator(ITextEditor textEditor)
         {
             if (StatusBar == null) return;

src/Notepads/Views/MainPage/NotepadsMainPage.xaml

@@ -1,4 +1,4 @@
-<Page
+<Page
     x:Class="Notepads.Views.MainPage.NotepadsMainPage"
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
@@ -289,6 +289,7 @@
                 <ColumnDefinition Width="Auto"/>
                 <ColumnDefinition Width="Auto"/>
                 <ColumnDefinition Width="Auto"/>
+                <ColumnDefinition Width="Auto"/>
             </Grid.ColumnDefinitions>
             <Grid Column="0">
                 <Grid x:Name="FileModificationStateIndicator"
@@ -488,7 +489,12 @@
                            Tapped="StatusBarComponent_OnTapped">
                 </TextBlock>
             </Grid>
-            <Grid Column="4"
+            <Grid Column="4">
+                <TextBlock x:Name="WordCountIndicator" Style="{StaticResource StatusBarTextBlockStyle}"
+                           IsHitTestVisible="False">
+                </TextBlock>
+            </Grid>
+            <Grid Column="5"
                   ui:FrameworkElementExtensions.Cursor="Hand">
                 <Interactivity:Interaction.Behaviors>
                     <Core:EventTriggerBehavior EventName="PointerEntered">
@@ -580,7 +586,7 @@
                     </TextBlock.ContextFlyout>
                 </TextBlock>
             </Grid>
-            <Grid Column="5"
+            <Grid Column="6"
                   ui:FrameworkElementExtensions.Cursor="Hand">
                 <Interactivity:Interaction.Behaviors>
                     <Core:EventTriggerBehavior EventName="PointerEntered">
@@ -617,7 +623,7 @@
                     </TextBlock.ContextFlyout>
                 </TextBlock>
             </Grid>
-            <Grid Column="6"
+            <Grid Column="7"
                   ui:FrameworkElementExtensions.Cursor="Hand">
                 <Interactivity:Interaction.Behaviors>
                     <Core:EventTriggerBehavior EventName="PointerEntered">
@@ -651,7 +657,7 @@
                     </TextBlock.ContextFlyout>
                 </TextBlock>
             </Grid>
-            <Grid Column="7"
+            <Grid Column="8"
                   ui:FrameworkElementExtensions.Cursor="Hand">
                 <Interactivity:Interaction.Behaviors>
                     <Core:EventTriggerBehavior EventName="PointerEntered">

src/Notepads/Views/MainPage/NotepadsMainPage.xaml.cs

@@ -1,4 +1,4 @@
-// ---------------------------------------------------------------------------------------------
+// ---------------------------------------------------------------------------------------------
 //  Copyright (c) 2019-2024, Jiaqi (0x7c13) Liu. All rights reserved.
 //  See LICENSE file in the project root for license information.
 // ---------------------------------------------------------------------------------------------
@@ -62,7 +62,8 @@ private INotepadsCore NotepadsCore
                 _notepadsCore.TextEditorSaved += OnTextEditorSaved;
                 _notepadsCore.TextEditorMovedToAnotherAppInstance += OnTextEditorMovedToAnotherAppInstance;
                 _notepadsCore.TextEditorRenamed += (sender, editor) => { if (NotepadsCore.GetSelectedTextEditor() == editor) SetupStatusBar(editor); };
-                _notepadsCore.TextEditorSelectionChanged += (sender, editor) => { if (NotepadsCore.GetSelectedTextEditor() == editor) UpdateLineColumnIndicator(editor); };
+                _notepadsCore.TextEditorSelectionChanged += (sender, editor) => { if (NotepadsCore.GetSelectedTextEditor() == editor) { UpdateLineColumnIndicator(editor); UpdateWordCountIndicator(editor); } };
+                _notepadsCore.TextEditorTextChanging += (_, editor) => { if (NotepadsCore.GetSelectedTextEditor() == editor) UpdateWordCountIndicator(editor); };
                 _notepadsCore.TextEditorFontZoomFactorChanged += (sender, editor) => { if (NotepadsCore.GetSelectedTextEditor() == editor) UpdateFontZoomIndicator(editor); };
                 _notepadsCore.TextEditorEncodingChanged += (sender, editor) => { if (NotepadsCore.GetSelectedTextEditor() == editor) UpdateEncodingIndicator(editor.GetEncoding()); };
                 _notepadsCore.TextEditorLineEndingChanged += (sender, editor) => { if (NotepadsCore.GetSelectedTextEditor() == editor) { UpdateLineEndingIndicator(editor.GetLineEnding()); UpdateLineColumnIndicator(editor); } };