29WxOrder/29WxOrderWpf/Ctrls/Statistics/Charts/RevenuePieChart.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Shapes;
using _29WxOrderWpf.Ctrls.Statistics.Models;

namespace _29WxOrderWpf.Ctrls.Statistics.Charts
{
	/// <summary>
	/// 店铺销售占比饼图（轻量自绘，无第三方依赖）。
	/// 绑定 <see cref="ItemsSource"/>（IList&lt;ShopSalesProportionItem&gt;）即可，数据变化时自动重绘。
	/// 设置 <see cref="MaxItems"/>（&gt;0）可只显示前 N 项，其余项合并为一个“<see cref="OtherLabel"/>”扇区（百分比为剩余总和，整体仍为 100%）。
	/// 设置 <see cref="Title"/> 可在环形图中央留白处显示标题（<see cref="TitlePlacement"/> 可切换为顶部），不会遮挡扇形；
	/// 图例通过 <see cref="LegendPosition"/> 可放置到 4 个角，饼图区域由独立 panel 包裹，方便整体挪动和调整大小。
	/// </summary>
	public partial class RevenuePieChart : UserControl
	{
		/// <summary>标题显示位置</summary>
		public enum PieTitlePlacement
		{
			/// <summary>居中显示在环形图中央留白处（默认，不遮挡扇形）</summary>
			Center,

			/// <summary>显示在图表顶部</summary>
			Top
		}

		/// <summary>图例显示位置（4 个角）</summary>
		public enum PieLegendPosition
		{
			/// <summary>左上角</summary>
			TopLeft,

			/// <summary>右上角（默认）</summary>
			TopRight,

			/// <summary>左下角</summary>
			BottomLeft,

			/// <summary>右下角</summary>
			BottomRight
		}

		/// <summary>待绘制扇区（含颜色）</summary>
		private sealed class DisplaySlice
		{
			public ShopSalesProportionItem Item;
			public Brush Brush;
		}

		/// <summary>ECharts 默认配色</summary>
		private static readonly Color[] Palette =
		{
			Color.FromRgb(84, 112, 198),
			Color.FromRgb(145, 204, 117),
			Color.FromRgb(250, 200, 88),
			Color.FromRgb(238, 102, 102),
			Color.FromRgb(115, 192, 222),
			Color.FromRgb(59, 162, 114),
			Color.FromRgb(252, 132, 82),
			Color.FromRgb(154, 96, 180),
			Color.FromRgb(234, 124, 204)
		};

		/// <summary>“其他”合并项默认颜色（灰色）</summary>
		private static readonly Color OtherColor = Color.FromRgb(192, 196, 204);

		public static readonly DependencyProperty ItemsSourceProperty =
			DependencyProperty.Register("ItemsSource", typeof(IList<ShopSalesProportionItem>), typeof(RevenuePieChart),
				new PropertyMetadata(null, OnRenderPropertyChanged));

		/// <summary>占比数据</summary>
		public IList<ShopSalesProportionItem> ItemsSource
		{
			get { return (IList<ShopSalesProportionItem>)GetValue(ItemsSourceProperty); }
			set { SetValue(ItemsSourceProperty, value); }
		}

		public static readonly DependencyProperty MaxItemsProperty =
			DependencyProperty.Register("MaxItems", typeof(int), typeof(RevenuePieChart),
				new PropertyMetadata(0, OnRenderPropertyChanged));

		/// <summary>最多显示的独立扇区数（&gt;0 时其余项合并为“其他”；&lt;=0 显示全部）</summary>
		public int MaxItems
		{
			get { return (int)GetValue(MaxItemsProperty); }
			set { SetValue(MaxItemsProperty, value); }
		}

		public static readonly DependencyProperty OtherLabelProperty =
			DependencyProperty.Register("OtherLabel", typeof(string), typeof(RevenuePieChart),
				new PropertyMetadata("其他", OnRenderPropertyChanged));

		/// <summary>合并项的显示名称（默认“其他”）</summary>
		public string OtherLabel
		{
			get { return (string)GetValue(OtherLabelProperty); }
			set { SetValue(OtherLabelProperty, value); }
		}

		public static readonly DependencyProperty OtherBrushProperty =
			DependencyProperty.Register("OtherBrush", typeof(Brush), typeof(RevenuePieChart),
				new PropertyMetadata(new SolidColorBrush(OtherColor), OnRenderPropertyChanged));

		/// <summary>合并项的颜色（默认灰色）</summary>
		public Brush OtherBrush
		{
			get { return (Brush)GetValue(OtherBrushProperty); }
			set { SetValue(OtherBrushProperty, value); }
		}

		public static readonly DependencyProperty TitleProperty =
			DependencyProperty.Register("Title", typeof(string), typeof(RevenuePieChart),
				new PropertyMetadata(null, OnRenderPropertyChanged));

		/// <summary>标题文本（空/Null 不显示）</summary>
		public string Title
		{
			get { return (string)GetValue(TitleProperty); }
			set { SetValue(TitleProperty, value); }
		}

		public static readonly DependencyProperty TitlePlacementProperty =
			DependencyProperty.Register("TitlePlacement", typeof(PieTitlePlacement), typeof(RevenuePieChart),
				new PropertyMetadata(PieTitlePlacement.Center, OnRenderPropertyChanged));

		/// <summary>标题显示位置（默认居中显示在环形图留白处，不遮挡扇形）</summary>
		public PieTitlePlacement TitlePlacement
		{
			get { return (PieTitlePlacement)GetValue(TitlePlacementProperty); }
			set { SetValue(TitlePlacementProperty, value); }
		}

		public static readonly DependencyProperty TitleFontSizeProperty =
			DependencyProperty.Register("TitleFontSize", typeof(double), typeof(RevenuePieChart),
				new PropertyMetadata(14d, OnRenderPropertyChanged));

		/// <summary>标题字号</summary>
		public double TitleFontSize
		{
			get { return (double)GetValue(TitleFontSizeProperty); }
			set { SetValue(TitleFontSizeProperty, value); }
		}

		public static readonly DependencyProperty TitleBrushProperty =
			DependencyProperty.Register("TitleBrush", typeof(Brush), typeof(RevenuePieChart),
				new PropertyMetadata(new SolidColorBrush(Color.FromRgb(51, 51, 51)), OnRenderPropertyChanged));

		/// <summary>标题颜色</summary>
		public Brush TitleBrush
		{
			get { return (Brush)GetValue(TitleBrushProperty); }
			set { SetValue(TitleBrushProperty, value); }
		}

		public static readonly DependencyProperty LegendPositionProperty =
			DependencyProperty.Register("LegendPosition", typeof(PieLegendPosition), typeof(RevenuePieChart),
				new PropertyMetadata(PieLegendPosition.TopRight, OnRenderPropertyChanged));

		/// <summary>图例显示位置（默认右上角，与饼图分列放置，不遮挡）</summary>
		public PieLegendPosition LegendPosition
		{
			get { return (PieLegendPosition)GetValue(LegendPositionProperty); }
			set { SetValue(LegendPositionProperty, value); }
		}

		public RevenuePieChart()
		{
			InitializeComponent();
			Loaded += delegate { Render(); };
			SizeChanged += delegate { Render(); };
		}

		private static void OnRenderPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
		{
			((RevenuePieChart)d).Render();
		}

		private void Render()
		{
			LayoutRoot.Children.Clear();
			var items = ItemsSource;
			if (items == null || items.Count == 0 || ActualWidth <= 20 || ActualHeight <= 20)
				return;

			double width = ActualWidth;
			double height = ActualHeight;

			// 图例列宽：图例占左/右一列，饼图占另一列，天然不会互相遮挡
			double legendWidth = Math.Min(210, width * 0.38);
			bool legendOnLeft = LegendPosition == PieLegendPosition.TopLeft
				|| LegendPosition == PieLegendPosition.BottomLeft;

			double pieLeft = legendOnLeft ? legendWidth : 0;
			double pieWidth = Math.Max(10, width - legendWidth);
			double pieHeight = height;

			// 顶部标题：先预留高度，饼图相应下移，避免遮挡
			double topTitleHeight = 0;
			if (TitlePlacement == PieTitlePlacement.Top && !string.IsNullOrEmpty(Title))
			{
				var probe = CreateTitleBlock(pieWidth);
				probe.Measure(new Size(pieWidth, double.PositiveInfinity));
				topTitleHeight = Math.Ceiling(probe.DesiredSize.Height) + 8;
			}

			// 饼图区域用独立 Canvas 包裹，方便整体挪动（SetLeft/SetTop）和修改大小（Width/Height）
			var piePanel = new Canvas { Width = pieWidth, Height = pieHeight };
			LayoutRoot.Children.Add(piePanel);
			Canvas.SetLeft(piePanel, pieLeft);
			Canvas.SetTop(piePanel, 0);

			double cx = pieWidth / 2;
			double cy = (topTitleHeight + pieHeight) / 2;
			double radius = Math.Max(10, Math.Min(pieWidth, pieHeight - topTitleHeight) / 2 - 18);

			// 0. 生成实际绘制的扇区列表（MaxItems &gt; 0 时其余项合并为“其他”）
			var slices = BuildSlices(items);

			// 1. 绘制扇形
			double startAngle = -90; // 从正上方开始，顺时针
			foreach (var slice in slices)
			{
				double sweep = slice.Item.Percentage / 100d * 360d;
				if (sweep < 0) sweep = 0;
				var brush = slice.Brush;

				if (sweep >= 359.9)
				{
					var circle = new Ellipse
					{
						Width = radius * 2,
						Height = radius * 2,
						Fill = brush
					};
					piePanel.Children.Add(circle);
					Canvas.SetLeft(circle, cx - radius);
					Canvas.SetTop(circle, cy - radius);
				}
				else if (sweep > 0.01)
				{
					piePanel.Children.Add(CreateSlice(cx, cy, radius, startAngle, sweep, brush));
				}
				startAngle += sweep;
			}

			// 2. 中间留白圆心
			double holeRadius = radius * 0.55;
			var hole = new Ellipse
			{
				Width = holeRadius * 2,
				Height = holeRadius * 2,
				Fill = Brushes.White
			};
			piePanel.Children.Add(hole);
			Canvas.SetLeft(hole, cx - holeRadius);
			Canvas.SetTop(hole, cy - holeRadius);

			// 3. 标题（居中显示在环形图留白处，宽度限制在留白直径内，不遮挡扇形）
			if (!string.IsNullOrEmpty(Title))
			{
				double maxW = TitlePlacement == PieTitlePlacement.Center
					? Math.Max(20, holeRadius * 2 - 8)
					: pieWidth;
				var titleBlock = CreateTitleBlock(maxW);
				titleBlock.Measure(new Size(maxW, double.PositiveInfinity));
				double w = Math.Min(titleBlock.DesiredSize.Width, maxW);
				double h = titleBlock.DesiredSize.Height;

				piePanel.Children.Add(titleBlock);
				Canvas.SetLeft(titleBlock, cx - w / 2);
				Canvas.SetTop(titleBlock, TitlePlacement == PieTitlePlacement.Center ? cy - h / 2 : 0);
			}

			// 4. 图例（4 个角可设置，与饼图分列，不遮挡）
			var legendPanel = CreateLegendPanel(slices, legendWidth - 16);
			legendPanel.Measure(new Size(double.PositiveInfinity, double.PositiveInfinity));
			double legendW = legendPanel.DesiredSize.Width;
			double legendH = legendPanel.DesiredSize.Height;

			const double padding = 8;
			double lx, ly;
			if (LegendPosition == PieLegendPosition.TopLeft || LegendPosition == PieLegendPosition.TopRight)
				ly = padding;
			else
				ly = Math.Max(padding, height - legendH - padding);
			lx = legendOnLeft ? padding : width - legendW - padding;

			LayoutRoot.Children.Add(legendPanel);
			Canvas.SetLeft(legendPanel, lx);
			Canvas.SetTop(legendPanel, ly);
		}

		/// <summary>
		/// 根据 <see cref="MaxItems"/> 生成实际绘制的扇区列表：
		/// 按占比从大到小取前 N 项单独显示，其余项合并为一个“其他”扇区（百分比为剩余总和，整体仍为 100%）。
		/// </summary>
		private List<DisplaySlice> BuildSlices(IList<ShopSalesProportionItem> items)
		{
			var result = new List<DisplaySlice>();
			if (items == null || items.Count == 0)
				return result;

			var ordered = items
				.OrderByDescending(i => i.Percentage)
				.ThenByDescending(i => i.SalesAmount)
				.ToList();

			int max = MaxItems > 0 ? MaxItems : ordered.Count;
			if (max >= ordered.Count)
			{
				for (int i = 0; i < ordered.Count; i++)
					result.Add(new DisplaySlice
					{
						Item = ordered[i],
						Brush = new SolidColorBrush(Palette[i % Palette.Length])
					});
				return result;
			}

			for (int i = 0; i < max; i++)
				result.Add(new DisplaySlice
				{
					Item = ordered[i],
					Brush = new SolidColorBrush(Palette[i % Palette.Length])
				});

			var rest = ordered.Skip(max).ToList();
			result.Add(new DisplaySlice
			{
				Item = new ShopSalesProportionItem
				{
					ShopName = string.IsNullOrEmpty(OtherLabel) ? "其他" : OtherLabel,
					Percentage = rest.Sum(r => r.Percentage),
					SalesAmount = rest.Sum(r => r.SalesAmount)
				},
				Brush = OtherBrush ?? new SolidColorBrush(OtherColor)
			});
			return result;
		}

		private TextBlock CreateTitleBlock(double maxWidth)
		{
			var brush = TitleBrush ?? new SolidColorBrush(Color.FromRgb(51, 51, 51));
			return new TextBlock
			{
				Text = Title,
				FontSize = TitleFontSize,
				FontWeight = FontWeights.Bold,
				Foreground = brush,
				TextAlignment = TextAlignment.Center,
				TextWrapping = TextWrapping.Wrap,
				TextTrimming = TextTrimming.CharacterEllipsis,
				MaxWidth = maxWidth
			};
		}

		private static StackPanel CreateLegendPanel(IList<DisplaySlice> slices, double maxWidth)
		{
			double maxLegendWidth = Math.Max(60, maxWidth);
			var legendPanel = new StackPanel { MaxWidth = maxLegendWidth };
			foreach (var slice in slices)
			{
				var legendRow = new StackPanel
				{
					Orientation = Orientation.Horizontal,
					Margin = new Thickness(0, 4, 0, 4)
				};
				legendRow.Children.Add(new Rectangle
				{
					Width = 12,
					Height = 12,
					Fill = slice.Brush
				});

				var text = new TextBlock
				{
					Text = slice.Item.ShopName + "  " + slice.Item.Percentage.ToString("0.0") + "%",
					FontSize = 12,
					Foreground = new SolidColorBrush(Color.FromRgb(102, 102, 102)),
					Margin = new Thickness(6, 0, 0, 0),
					VerticalAlignment = VerticalAlignment.Center,
					MaxWidth = Math.Max(40, maxLegendWidth - 18),
					TextTrimming = TextTrimming.CharacterEllipsis
				};
				legendRow.Children.Add(text);
				legendPanel.Children.Add(legendRow);
			}
			return legendPanel;
		}

		private static Path CreateSlice(double cx, double cy, double radius, double startAngle, double sweep, Brush fill)
		{
			var start = PointOnCircle(cx, cy, radius, startAngle);
			var end = PointOnCircle(cx, cy, radius, startAngle + sweep);

			var figure = new PathFigure { StartPoint = new Point(cx, cy), IsClosed = true, IsFilled = true };
			figure.Segments.Add(new LineSegment { Point = start });
			figure.Segments.Add(new ArcSegment
			{
				Point = end,
				Size = new Size(radius, radius),
				IsLargeArc = sweep > 180,
				SweepDirection = SweepDirection.Clockwise
			});

			return new Path
			{
				Data = new PathGeometry { Figures = { figure } },
				Fill = fill,
				Stroke = Brushes.White,
				StrokeThickness = 1
			};
		}

		private static Point PointOnCircle(double cx, double cy, double radius, double angle)
		{
			double rad = angle * Math.PI / 180d;
			return new Point(cx + radius * Math.Cos(rad), cy + radius * Math.Sin(rad));
		}
	}
}