refactor: support pie chart

axis.go

@@ -37,6 +37,7 @@ type (
 		// 'log' 对数轴。适用于对数数据。
 		Type        string
 		Data        []string
+		SplitNumber int
 	}
 )
 
@@ -44,6 +45,7 @@ const axisStrokeWidth = 1
 
 func GetXAxisAndValues(xAxis XAxis, tickPosition chart.TickPosition, theme string) (chart.XAxis, []float64) {
 	data := xAxis.Data
+	originalSize := len(data)
 	// 如果居中，则需要多添加一个值
 	if tickPosition == chart.TickPositionBetweenTicks {
 		data = append([]string{
@@ -51,14 +53,36 @@ func GetXAxisAndValues(xAxis XAxis, tickPosition chart.TickPosition, theme strin
 		}, data...)
 	}
 
-	xValues := make([]float64, len(data))
+	size := len(data)
-	ticks := make([]chart.Tick, len(data))
+
+	xValues := make([]float64, size)
+	ticks := make([]chart.Tick, 0)
+
+	maxTicks := xAxis.SplitNumber
+	if maxTicks == 0 {
+		maxTicks = 10
+	}
+
+	// 计息最多每个unit至少放多个
+	minUnitSize := originalSize / maxTicks
+	if originalSize%maxTicks != 0 {
+		minUnitSize++
+	}
+	unitSize := minUnitSize
+	for i := minUnitSize; i < 2*minUnitSize; i++ {
+		if originalSize%i == 0 {
+			unitSize = i
+		}
+	}
+
 	for index, key := range data {
 		f := float64(index)
 		xValues[index] = f
-		ticks[index] = chart.Tick{
+		if index%unitSize == 0 || index == size-1 {
+			ticks = append(ticks, chart.Tick{
 				Value: f,
 				Label: key,
+			})
 		}
 	}
 	// TODO

bar_series.go

@@ -28,6 +28,12 @@ import (
 
 const defaultBarMargin = 10
 
+type BarSeriesCustomStyle struct {
+	PointIndex int
+	Index      int
+	Style      chart.Style
+}
+
 type BarSeries struct {
 	BaseSeries
 	Count int
@@ -38,6 +44,16 @@ type BarSeries struct {
 	Offset int
 	// 宽度
 	BarWidth     int
+	CustomStyles []BarSeriesCustomStyle
+}
+
+func (bs BarSeries) GetBarStyle(index, pointIndex int) chart.Style {
+	for _, item := range bs.CustomStyles {
+		if item.Index == index && item.PointIndex == pointIndex {
+			return item.Style
+		}
+	}
+	return chart.Style{}
 }
 
 func (bs BarSeries) Render(r chart.Renderer, canvasBox chart.Box, xrange, yrange chart.Range, defaults chart.Style) {
@@ -79,6 +95,12 @@ func (bs BarSeries) Render(r chart.Renderer, canvasBox chart.Box, xrange, yrange
 
 	for i := 0; i < bs.Len(); i++ {
 		vx, vy := bs.GetValues(i)
+		customStyle := bs.GetBarStyle(bs.Index, i)
+		cloneStyle := style
+		if !customStyle.IsZero() {
+			cloneStyle.FillColor = customStyle.FillColor
+			cloneStyle.StrokeColor = customStyle.StrokeColor
+		}
 
 		x := cl + xrange.Translate(vx)
 		// 由于bar是居中展示，因此需要往前移一个显示块
@@ -92,6 +114,6 @@ func (bs BarSeries) Render(r chart.Renderer, canvasBox chart.Box, xrange, yrange
 			Top:    y,
 			Right:  x + barWidth,
 			Bottom: canvasBox.Bottom - 1,
-		}, style)
+		}, cloneStyle)
 	}
 }

charts.go

@@ -24,10 +24,17 @@ package charts
 
 import (
 	"bytes"
+	"errors"
+	"io"
 
 	"github.com/wcharczuk/go-chart/v2"
 )
 
+const (
+	ThemeLight = "light"
+	ThemeDark  = "dark"
+)
+
 type (
 	Title struct {
 		Text string
@@ -46,7 +53,13 @@ type (
 		Legend       Legend
 		TickPosition chart.TickPosition
 	}
-	ECharOption struct {
+)
+
+type Chart interface {
+	Render(rp chart.RendererProvider, w io.Writer) error
+}
+
+type ECharOption struct {
 	Title struct {
 		Text      string
 		TextStyle struct {
@@ -56,18 +69,27 @@ type (
 	}
 	XAxis struct {
 		Type        string
-			BoundaryGap bool
+		BoundaryGap *bool
+		SplitNumber int
 		Data        []string
 	}
 }
-)
 
-const (
+func (o *Option) validate() error {
-	ThemeLight = "light"
+	xAxisCount := len(o.XAxis.Data)
-	ThemeDark  = "dark"
+	if len(o.Series) == 0 {
-)
+		return errors.New("series can not be empty")
+	}
 
-func render(c *chart.Chart, rp chart.RendererProvider) ([]byte, error) {
+	for _, item := range o.Series {
+		if len(item.Data) != xAxisCount {
+			return errors.New("series and xAxis is not matched")
+		}
+	}
+	return nil
+}
+
+func render(c Chart, rp chart.RendererProvider) ([]byte, error) {
 	buf := bytes.Buffer{}
 	err := c.Render(rp, &buf)
 	if err != nil {
@@ -76,14 +98,18 @@ func render(c *chart.Chart, rp chart.RendererProvider) ([]byte, error) {
 	return buf.Bytes(), nil
 }
 
-func ToPNG(c *chart.Chart) ([]byte, error) {
+func ToPNG(c Chart) ([]byte, error) {
 	return render(c, chart.PNG)
 }
 
-func ToSVG(c *chart.Chart) ([]byte, error) {
+func ToSVG(c Chart) ([]byte, error) {
 	return render(c, chart.SVG)
 }
-func New(opt Option) *chart.Chart {
+func New(opt Option) (Chart, error) {
+	err := opt.validate()
+	if err != nil {
+		return nil, err
+	}
 	tickPosition := opt.TickPosition
 
 	xAxis, xValues := GetXAxisAndValues(opt.XAxis, tickPosition, opt.Theme)
@@ -97,6 +123,25 @@ func New(opt Option) *chart.Chart {
 			opt.Series[index].Name = opt.Legend.Data[index]
 		}
 	}
+	if opt.Series[0].Type == SeriesPie {
+		values := make(chart.Values, len(opt.Series))
+		for index, item := range opt.Series {
+			values[index] = chart.Value{
+				Value: item.Data[0].Value,
+				Label: item.Name,
+			}
+		}
+		c := &chart.PieChart{
+			Title:  opt.Title.Text,
+			Width:  opt.Width,
+			Height: opt.Height,
+			Values: values,
+			ColorPalette: &ThemeColorPalette{
+				Theme: opt.Theme,
+			},
+		}
+		return c, nil
+	}
 
 	c := &chart.Chart{
 		Title:  opt.Title.Text,
@@ -106,7 +151,7 @@ func New(opt Option) *chart.Chart {
 		YAxis:  GetYAxis(opt.Theme),
 		Series: GetSeries(opt.Series, tickPosition, opt.Theme),
 	}
-	// TODO 校验xAxis与yAxis的数量是否一致
+
 	// 设置secondary的样式
 	c.YAxisSecondary.Style = c.YAxis.Style
 	if legendSize != 0 {
@@ -114,5 +159,5 @@ func New(opt Option) *chart.Chart {
 			DefaultLegend(c),
 		}
 	}
-	return c
+	return c, nil
 }

series.go

@@ -24,13 +24,16 @@ package charts
 
 import (
 	"github.com/wcharczuk/go-chart/v2"
-	"github.com/wcharczuk/go-chart/v2/drawing"
 )
 
+type SeriesData struct {
+	Value float64
+	Style chart.Style
+}
 type Series struct {
 	Type    string
 	Name    string
-	Data    []float64
+	Data    []SeriesData
 	XValues []float64
 }
 
@@ -40,15 +43,9 @@ const dotWith = 2
 const (
 	SeriesBar  = "bar"
 	SeriesLine = "line"
+	SeriesPie  = "pie"
 )
 
-func getSeriesColor(theme string, index int) drawing.Color {
-	// TODO
-	if theme == ThemeDark {
-	}
-	return SeriesColorsLight[index%len(SeriesColorsLight)]
-}
-
 func GetSeries(series []Series, tickPosition chart.TickPosition, theme string) []chart.Series {
 	arr := make([]chart.Series, len(series))
 	barCount := 0
@@ -58,25 +55,41 @@ func GetSeries(series []Series, tickPosition chart.TickPosition, theme string) [
 			barCount++
 		}
 	}
+
 	for index, item := range series {
 		style := chart.Style{
 			StrokeWidth: lineStrokeWidth,
 			StrokeColor: getSeriesColor(theme, index),
+			// FillColor:   getSeriesColor(theme, index),
 			// TODO 调整为通过dot with color 生成
 			DotColor: getSeriesColor(theme, index),
 			DotWidth: dotWith,
 		}
 		// 如果居中，需要多增加一个点
 		if tickPosition == chart.TickPositionBetweenTicks {
-			item.Data = append([]float64{
+			item.Data = append([]SeriesData{
-				0.0,
+				{
+					Value: 0.0,
+				},
 			}, item.Data...)
 		}
+		yValues := make([]float64, len(item.Data))
+		barCustomStyles := make([]BarSeriesCustomStyle, 0)
+		for i, item := range item.Data {
+			yValues[i] = item.Value
+			if !item.Style.IsZero() {
+				barCustomStyles = append(barCustomStyles, BarSeriesCustomStyle{
+					PointIndex: i,
+					Index:      barIndex,
+					Style:      item.Style,
+				})
+			}
+		}
 		baseSeries := BaseSeries{
 			Name:         item.Name,
 			XValues:      item.XValues,
 			Style:        style,
-			YValues:      item.Data,
+			YValues:      yValues,
 			TickPosition: tickPosition,
 		}
 		// TODO 判断类型
@@ -86,6 +99,7 @@ func GetSeries(series []Series, tickPosition chart.TickPosition, theme string) [
 				Count:        barCount,
 				Index:        barIndex,
 				BaseSeries:   baseSeries,
+				CustomStyles: barCustomStyles,
 			}
 			barIndex++
 		default:

theme.go

@@ -22,7 +22,10 @@
 
 package charts
 
-import "github.com/wcharczuk/go-chart/v2/drawing"
+import (
+	"github.com/wcharczuk/go-chart/v2"
+	"github.com/wcharczuk/go-chart/v2/drawing"
+)
 
 var hiddenColor = drawing.Color{R: 110, G: 112, B: 121, A: 0}
 
@@ -65,3 +68,42 @@ var SeriesColorsLight = []drawing.Color{
 		A: 255,
 	},
 }
+
+type ThemeColorPalette struct {
+	Theme string
+}
+
+func (tp ThemeColorPalette) BackgroundColor() drawing.Color {
+	return chart.DefaultBackgroundColor
+}
+
+func (tp ThemeColorPalette) BackgroundStrokeColor() drawing.Color {
+	return chart.DefaultBackgroundStrokeColor
+}
+
+func (tp ThemeColorPalette) CanvasColor() drawing.Color {
+	return chart.DefaultCanvasColor
+}
+
+func (tp ThemeColorPalette) CanvasStrokeColor() drawing.Color {
+	return chart.DefaultCanvasStrokeColor
+}
+
+func (tp ThemeColorPalette) AxisStrokeColor() drawing.Color {
+	return chart.DefaultAxisColor
+}
+
+func (tp ThemeColorPalette) TextColor() drawing.Color {
+	return chart.DefaultTextColor
+}
+
+func (tp ThemeColorPalette) GetSeriesColor(index int) drawing.Color {
+	return getSeriesColor(tp.Theme, index)
+}
+
+func getSeriesColor(theme string, index int) drawing.Color {
+	// TODO
+	if theme == ThemeDark {
+	}
+	return SeriesColorsLight[index%len(SeriesColorsLight)]
+}