sampler-fork/component/barchart/barchart.go

165 lines
3.4 KiB
Go

package barchart
import (
"fmt"
ui "github.com/gizak/termui/v3"
rw "github.com/mattn/go-runewidth"
"github.com/sqshq/sampler/component"
"github.com/sqshq/sampler/component/util"
"github.com/sqshq/sampler/config"
"github.com/sqshq/sampler/console"
"github.com/sqshq/sampler/data"
"image"
"math"
)
const (
barIndent int = 1
)
type BarChart struct {
*ui.Block
*data.Consumer
bars []Bar
scale int
maxValue float64
count int64
palette console.Palette
}
type Bar struct {
label string
color ui.Color
value float64
delta float64
}
func NewBarChart(c config.BarChartConfig, palette console.Palette) *BarChart {
chart := BarChart{
Block: component.NewBlock(c.Title, true, palette),
Consumer: data.NewConsumer(),
bars: []Bar{},
scale: *c.Scale,
maxValue: -math.MaxFloat64,
palette: palette,
}
for _, i := range c.Items {
chart.AddBar(*i.Label, *i.Color)
}
go func() {
for {
select {
case sample := <-chart.SampleChannel:
chart.consumeSample(sample)
case alert := <-chart.AlertChannel:
chart.Alert = alert
}
}
}()
return &chart
}
func (b *BarChart) consumeSample(sample *data.Sample) {
b.count++
float, err := util.ParseFloat(sample.Value)
if err != nil {
b.HandleConsumeFailure("Failed to parse a number", err, sample)
return
} else {
b.HandleConsumeSuccess()
}
index := -1
for i, bar := range b.bars {
if bar.label == sample.Label {
index = i
}
}
bar := b.bars[index]
bar.delta = float - bar.value
bar.value = float
b.bars[index] = bar
if float > b.maxValue {
b.maxValue = float
}
// normalize bars height once in a while
if b.count%500 == 0 {
b.reselectMaxValue()
}
}
func (b *BarChart) AddBar(label string, color ui.Color) {
b.bars = append(b.bars, Bar{label: label, color: color, value: 0})
}
func (b *BarChart) reselectMaxValue() {
maxValue := -math.MaxFloat64
for _, bar := range b.bars {
if bar.value > maxValue {
maxValue = bar.value
}
}
b.maxValue = maxValue
}
func (b *BarChart) Draw(buffer *ui.Buffer) {
b.Block.Draw(buffer)
barWidth := int(math.Floor(float64(b.Inner.Dx()-len(b.bars)*barIndent) / float64(len(b.bars))))
barXCoordinate := b.Inner.Min.X + barIndent
labelStyle := ui.NewStyle(b.palette.BaseColor)
for _, bar := range b.bars {
// draw bar
height := int((bar.value / b.maxValue) * float64(b.Inner.Dy()-1))
if height <= 1 {
height = 2
}
maxYCoordinate := b.Inner.Max.Y - height
for x := barXCoordinate; x < ui.MinInt(barXCoordinate+barWidth, b.Inner.Max.X-barIndent); x++ {
for y := b.Inner.Max.Y - 2; y >= maxYCoordinate; y-- {
c := ui.NewCell(console.SymbolHorizontalBar, ui.NewStyle(bar.color))
buffer.SetCell(c, image.Pt(x, y))
}
}
// draw label
labelXCoordinate := barXCoordinate +
int(float64(barWidth)/2) -
int(float64(rw.StringWidth(bar.label))/2)
buffer.SetString(
bar.label,
labelStyle,
image.Pt(labelXCoordinate, b.Inner.Max.Y-1))
// draw value & delta
value := util.FormatValue(bar.value, b.scale)
if bar.delta != 0 {
value = fmt.Sprintf("%s / %s", value, util.FormatValueWithSign(bar.delta, b.scale))
}
valueXCoordinate := barXCoordinate +
int(float64(barWidth)/2) -
int(float64(rw.StringWidth(value))/2)
buffer.SetString(
value,
labelStyle,
image.Pt(valueXCoordinate, maxYCoordinate-1))
barXCoordinate += barWidth + barIndent
}
component.RenderAlert(b.Alert, b.Rectangle, buffer)
}