package chart import ( "math" "time" "github.com/wcharczuk/go-chart" ) // CreateContinuousSeriesLastValueLabel returns a (1) value annotation series. func CreateContinuousSeriesLastValueLabel(name string, xvalues, yvalues []float64, valueFormatter ValueFormatter) AnnotationSeries { return AnnotationSeries{ Name: name, Style: Style{ Show: true, StrokeColor: chart.GetDefaultSeriesStrokeColor(0), }, Annotations: []chart.Annotation{ Annotation{ X: xvalues[len(xvalues)-1], Y: yvalues[len(yvalues)-1], Label: valueFormatter(yvalues[len(yvalues)-1]), }, }, } } // CreateTimeSeriesLastValueLabel returns a (1) value annotation series. func CreateTimeSeriesLastValueLabel(name string, xvalues []time.Time, yvalues []float64, valueFormatter ValueFormatter) AnnotationSeries { return AnnotationSeries{ Name: name, Style: Style{ Show: true, StrokeColor: chart.GetDefaultSeriesStrokeColor(0), }, Annotations: []chart.Annotation{ Annotation{ X: xvalues[len(xvalues)-1], Y: yvalues[len(yvalues)-1], Label: valueFormatter(yvalues[len(yvalues)-1]), }, }, } } // Annotation is a label on the chart. type Annotation struct { X, Y float64 Label string } // AnnotationSeries is a series of labels on the chart. type AnnotationSeries struct { Name string Style Style YAxis YAxisType Annotations []Annotation } // GetName returns the name of the time series. func (as AnnotationSeries) GetName() string { return as.Name } // GetStyle returns the line style. func (as AnnotationSeries) GetStyle() Style { return as.Style } // GetYAxis returns which YAxis the series draws on. func (as AnnotationSeries) GetYAxis() YAxisType { return as.YAxis } // Measure returns a bounds box of the series. func (as AnnotationSeries) Measure(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) Box { box := Box{ Top: math.MaxInt32, Left: math.MaxInt32, Right: 0, Bottom: 0, } if as.Style.Show { style := as.Style.WithDefaultsFrom(Style{ Font: defaults.Font, FillColor: DefaultAnnotationFillColor, FontSize: DefaultAnnotationFontSize, StrokeColor: defaults.StrokeColor, StrokeWidth: defaults.StrokeWidth, Padding: DefaultAnnotationPadding, }) for _, a := range as.Annotations { lx := canvasBox.Right - xrange.Translate(a.X) ly := yrange.Translate(a.Y) + canvasBox.Top ab := MeasureAnnotation(r, canvasBox, xrange, yrange, style, lx, ly, a.Label) if ab.Top < box.Top { box.Top = ab.Top } if ab.Left < box.Left { box.Left = ab.Left } if ab.Right > box.Right { box.Right = ab.Right } if ab.Bottom > box.Bottom { box.Bottom = ab.Bottom } } } return box } // Render draws the series. func (as AnnotationSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) { if as.Style.Show { style := as.Style.WithDefaultsFrom(Style{ Font: defaults.Font, FillColor: DefaultAnnotationFillColor, FontSize: DefaultAnnotationFontSize, StrokeColor: defaults.StrokeColor, StrokeWidth: defaults.StrokeWidth, Padding: DefaultAnnotationPadding, }) for _, a := range as.Annotations { lx := canvasBox.Right - xrange.Translate(a.X) ly := yrange.Translate(a.Y) + canvasBox.Top DrawAnnotation(r, canvasBox, xrange, yrange, style, lx, ly, a.Label) } } }