feat: start pagination.

src/Ursa/Controls/Pagination/Pagination.cs

@@ -1,8 +1,143 @@
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Controls.Metadata;
 using Avalonia.Controls.Primitives;
+using Avalonia.Interactivity;
+using Avalonia.Styling;
 
 namespace Ursa.Controls;
 
+[TemplatePart(PART_PreviousButton, typeof(Button))]
+[TemplatePart(PART_NextButton, typeof(Button))]
+[TemplatePart(PART_ButtonPanel, typeof(StackPanel))]
 public class Pagination: TemplatedControl
 {
+    public const string PART_PreviousButton = "PART_PreviousButton";
+    public const string PART_NextButton = "PART_NextButton";
+    public const string PART_ButtonPanel = "PART_ButtonPanel";
+    private Button? _previousButton;
+    private Button? _nextButton;
+    private StackPanel? _buttonPanel;
+
+    protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
+    {
+        base.OnApplyTemplate(e);
+        if (_previousButton != null) _previousButton.Click -= OnButtonClick;
+        if (_nextButton != null) _nextButton.Click -= OnButtonClick;
+        _previousButton = e.NameScope.Find<Button>(PART_PreviousButton);
+        _nextButton = e.NameScope.Find<Button>(PART_NextButton);
+        _buttonPanel = e.NameScope.Find<StackPanel>(PART_ButtonPanel);
+        if (_previousButton != null) _previousButton.Click += OnButtonClick;
+        if (_nextButton != null) _nextButton.Click += OnButtonClick;
+    }
+    
+    public static readonly StyledProperty<int> CurrentPageProperty = AvaloniaProperty.Register<Pagination, int>(
+        nameof(CurrentPage));
+    
+    public int CurrentPage
+    {
+        get => GetValue(CurrentPageProperty);
+        set {
+            int actualValue = CoercePage(value);
+            SetValue(CurrentPageProperty, actualValue);
+        }
+    }
+
+    public static readonly StyledProperty<int> TotalCountProperty = AvaloniaProperty.Register<Pagination, int>(
+        nameof(TotalCount));
+
+    /// <summary>
+    /// Total count of items. 
+    /// </summary>
+    public int TotalCount
+    {
+        get => GetValue(TotalCountProperty);
+        set => SetValue(TotalCountProperty, value);
+    }
+    
+    public static readonly StyledProperty<int> PageSizeProperty = AvaloniaProperty.Register<Pagination, int>(
+        nameof(PageSize));
+    
+    /// <summary>
+    /// Page size.
+    /// </summary>
+    public int PageSize
+    {
+        get => GetValue(PageSizeProperty);
+        set => SetValue(PageSizeProperty, value);
+    }
+
+    private int _pageCount;
+
+    public static readonly DirectProperty<Pagination, int> PageCountProperty = AvaloniaProperty.RegisterDirect<Pagination, int>(
+        nameof(PageCount), o => o.PageCount);
+
+    /// <summary>
+    /// Page count.
+    /// </summary>
+    public int PageCount
+    {
+        get => _pageCount;
+        private set => SetAndRaise(PageCountProperty, ref _pageCount, value);
+    }
+
+    private int _startIndex;
+
+    public static readonly DirectProperty<Pagination, int> StartIndexProperty = AvaloniaProperty.RegisterDirect<Pagination, int>(
+        nameof(StartIndex), o => o.StartIndex);
+
+    public int StartIndex
+    {
+        get => _startIndex;
+        private set => SetAndRaise(StartIndexProperty, ref _startIndex, value);
+    }
+
+    private int _endIndex;
+
+    public static readonly DirectProperty<Pagination, int> EndIndexProperty = AvaloniaProperty.RegisterDirect<Pagination, int>(
+        nameof(EndIndex), o => o.EndIndex);
+
+    public int EndIndex
+    {
+        get => _endIndex;
+        private set => SetAndRaise(EndIndexProperty, ref _endIndex, value);
+    }
+
+    public static readonly StyledProperty<ControlTheme> PageButtonThemeProperty = AvaloniaProperty.Register<Pagination, ControlTheme>(
+        nameof(PageButtonTheme));
+
+    public ControlTheme PageButtonTheme
+    {
+        get => GetValue(PageButtonThemeProperty);
+        set => SetValue(PageButtonThemeProperty, value);
+    }
+
+    public static readonly StyledProperty<ControlTheme> ExpandButtonThemeProperty = AvaloniaProperty.Register<Pagination, ControlTheme>(
+        nameof(ExpandButtonTheme));
+
+    public ControlTheme ExpandButtonTheme
+    {
+        get => GetValue(ExpandButtonThemeProperty);
+        set => SetValue(ExpandButtonThemeProperty, value);
+    }
+    
+    private void OnButtonClick(object? sender, RoutedEventArgs e)
+    {
+        if (Equals(sender, _previousButton))
+        {
+            CurrentPage--;
+        }
+        else
+        {
+            CurrentPage++;
+        }
+    }
+    
+    private int CoercePage(int page)
+    {
+        if (page < 1) return 1;
+        if (page > PageCount) return PageCount;
+        return page;
+    }
 
 }