Better handling of terminal resizing (#254)

* Better handling of terminal resizing

* Fixed dotnet-format error

Author: shibayan

Sharprompt.Tests/PropertyMetadataTests.cs

@@ -17,7 +17,7 @@ public void Basic()
         var metadata = PropertyMetadataFactory.Create(new BasicModel());
 
         Assert.NotNull(metadata);
-        Assert.Equal(1, metadata.Count);
+        Assert.Single(metadata);
 
         Assert.Equal(typeof(string), metadata[0].Type);
         Assert.Equal(FormType.Input, metadata[0].DetermineFormType());
@@ -27,7 +27,7 @@ public void Basic()
         Assert.False(metadata[0].IsCollection);
         Assert.Null(metadata[0].DefaultValue);
         Assert.Null(metadata[0].Order);
-        Assert.Equal(1, metadata[0].Validators.Count);
+        Assert.Single(metadata[0].Validators);
     }
 
     [Fact]
@@ -36,7 +36,7 @@ public void Basic_DefaultValue()
         var metadata = PropertyMetadataFactory.Create(new BasicModel { Value = "sample" });
 
         Assert.NotNull(metadata);
-        Assert.Equal(1, metadata.Count);
+        Assert.Single(metadata);
 
         Assert.Equal(typeof(string), metadata[0].Type);
         Assert.Equal("sample", metadata[0].DefaultValue);
@@ -182,7 +182,7 @@ public void BindIgnore()
         var metadata = PropertyMetadataFactory.Create(new BindIgnoreModel());
 
         Assert.NotNull(metadata);
-        Assert.Equal(1, metadata.Count);
+        Assert.Single(metadata);
     }
 
     [Fact]
@@ -191,7 +191,7 @@ public void ReadOnly()
         var metadata = PropertyMetadataFactory.Create(new ReadOnlyModel());
 
         Assert.NotNull(metadata);
-        Assert.Equal(1, metadata.Count);
+        Assert.Single(metadata);
     }
 
     [Fact]

Sharprompt.Tests/Sharprompt.Tests.csproj

@@ -7,9 +7,9 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.4.0" />
-    <PackageReference Include="xunit" Version="2.4.2" />
-    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.5">
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.7.0" />
+    <PackageReference Include="xunit" Version="2.5.0" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.5.0">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>

Sharprompt/Drivers/DefaultConsoleDriver.cs

@@ -76,7 +76,7 @@ public ConsoleKeyInfo ReadKey()
     {
         var keyInfo = Console.ReadKey(true);
 
-        if (keyInfo.Key == ConsoleKey.C && keyInfo.Modifiers == ConsoleModifiers.Control)
+        if (keyInfo is { Key: ConsoleKey.C, Modifiers: ConsoleModifiers.Control })
         {
             CancellationCallback.Invoke();
         }

Sharprompt/Forms/FormBase.cs

@@ -29,6 +29,8 @@ protected FormBase()
 
     protected Dictionary<ConsoleKey, Func<ConsoleKeyInfo, bool>> KeyHandlerMaps { get; set; } = new();
 
+    protected int Width => _consoleDriver.WindowWidth;
+
     protected int Height => _consoleDriver.WindowHeight;
 
     public void Dispose() => _formRenderer.Dispose();

Sharprompt/Forms/MultiSelectForm.cs

@@ -42,6 +42,8 @@ public MultiSelectForm(MultiSelectOptions<T> options)
 
     protected override void InputTemplate(OffscreenBuffer offscreenBuffer)
     {
+        _paginator.UpdatePageSize(Math.Min(_options.PageSize, Height - 2));
+
         offscreenBuffer.WritePrompt(_options.Message);
         offscreenBuffer.Write(_paginator.FilterKeyword);
 

Sharprompt/Forms/SelectForm.cs

@@ -31,6 +31,8 @@ public SelectForm(SelectOptions<T> options)
 
     protected override void InputTemplate(OffscreenBuffer offscreenBuffer)
     {
+        _paginator.UpdatePageSize(Math.Min(_options.PageSize, Height - 2));
+
         offscreenBuffer.WritePrompt(_options.Message);
         offscreenBuffer.Write(_paginator.FilterKeyword);
 

Sharprompt/Internal/OffscreenBuffer.cs

@@ -74,24 +74,28 @@ public void RenderToConsole()
 
         _cursorBottom = _consoleDriver.CursorTop;
 
-        if (_pushedCursor is not null)
+        if (_pushedCursor is null)
+        {
+            return;
+        }
+
+        var physicalLeft = _pushedCursor.Left % _consoleDriver.BufferWidth;
+        var physicalTop = _pushedCursor.Top + (_pushedCursor.Left / _consoleDriver.BufferWidth);
+
+        var consoleTop = _cursorBottom - WrittenLineCount + physicalTop;
+
+        if (_pushedCursor.Left > 0 && physicalLeft == 0)
         {
-            var physicalLeft = _pushedCursor.Left % _consoleDriver.BufferWidth;
-            var physicalTop = _pushedCursor.Top + (_pushedCursor.Left / _consoleDriver.BufferWidth);
+            _consoleDriver.WriteLine();
 
-            var consoleTop = _cursorBottom - WrittenLineCount + physicalTop;
-            if (_pushedCursor.Left > 0 && physicalLeft == 0)
+            if (consoleTop == _consoleDriver.BufferHeight)
             {
-                _consoleDriver.WriteLine();
-                if (consoleTop == _consoleDriver.BufferHeight)
-                {
-                    _cursorBottom--;
-                    consoleTop--;
-                }
+                _cursorBottom--;
+                consoleTop--;
             }
-
-            _consoleDriver.SetCursorPosition(physicalLeft, consoleTop);
         }
+
+        _consoleDriver.SetCursorPosition(physicalLeft, consoleTop);
     }
 
     public void ClearConsole(int cursorBottom, int writtenLineCount)

Sharprompt/Internal/Paginator.cs

@@ -18,9 +18,9 @@ public Paginator(IEnumerable<T> items, int pageSize, Optional<T> defaultValue, F
     }
 
     private readonly T[] _items;
-    private readonly int _pageSize;
     private readonly Func<T, string> _textSelector;
 
+    private int _pageSize;
     private T[] _filteredItems = Array.Empty<T>();
     private int _selectedIndex = -1;
 
@@ -94,11 +94,24 @@ public void UpdateFilter(string keyword)
         FilterKeyword = keyword;
 
         _selectedIndex = -1;
-        CurrentPage = 0;
 
         UpdateFilteredItems();
     }
 
+    public void UpdatePageSize(int newPageSize)
+    {
+        if (_pageSize == newPageSize)
+        {
+            return;
+        }
+
+        TryGetSelectedItem(out var selectedItem);
+
+        _pageSize = newPageSize <= 0 ? _items.Length : Math.Min(newPageSize, _items.Length);
+
+        InitializeDefaults(Optional<T>.Create(selectedItem));
+    }
+
     public IEnumerator<T> GetEnumerator() => (IEnumerator<T>)_filteredItems.GetEnumerator();
 
     IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
@@ -109,6 +122,11 @@ private void UpdateFilteredItems()
                                .ToArray();
 
         PageCount = (_filteredItems.Length - 1) / _pageSize + 1;
+
+        if (CurrentPage >= PageCount)
+        {
+            CurrentPage = 0;
+        }
     }
 
     private void InitializeDefaults(Optional<T> defaultValue)

Sharprompt/Internal/RenderScope.cs

@@ -10,8 +10,8 @@ public RenderScope(OffscreenBuffer offscreenBuffer, IConsoleDriver consoleDriver
     {
         _offscreenBuffer = offscreenBuffer;
         _consoleDriver = consoleDriver;
-        _cursorBottom = cursorBottom;
-        _writtenLineCount = writtenLineCount;
+        _cursorBottom = Math.Min(cursorBottom, _consoleDriver.WindowHeight - 1);
+        _writtenLineCount = Math.Min(writtenLineCount, _consoleDriver.WindowHeight - 1);
 
         _offscreenBuffer.ClearBuffer();
     }