sampler-fork/widgets/runchart/runchart.go

365 lines
7.9 KiB
Go

package runchart
import (
"fmt"
"github.com/sqshq/sampler/console"
"github.com/sqshq/sampler/data"
"image"
"math"
"strconv"
"sync"
"time"
ui "github.com/sqshq/termui"
)
const (
xAxisLabelsHeight = 1
xAxisLabelsWidth = 8
xAxisLabelsIndent = 2
xAxisGridWidth = xAxisLabelsIndent + xAxisLabelsWidth
yAxisLabelsHeight = 1
yAxisLabelsIndent = 1
historyReserveMin = 20
xBrailleMultiplier = 2
yBrailleMultiplier = 4
)
type Mode int
const (
ModeDefault Mode = 0
ModePinpoint Mode = 1
)
type RunChart struct {
ui.Block
lines []TimeLine
grid ChartGrid
timescale time.Duration
mutex *sync.Mutex
mode Mode
selection time.Time
scale int
legend Legend
}
type TimePoint struct {
value float64
time time.Time
coordinate int
}
type TimeLine struct {
points []TimePoint
extrema ValueExtrema
color ui.Color
label string
selectionCoordinate int
selectionPoint TimePoint
}
type TimeRange struct {
max time.Time
min time.Time
}
type ValueExtrema struct {
max float64
min float64
}
func NewRunChart(title string, scale int, refreshRateMs int, legend Legend) *RunChart {
block := *ui.NewBlock()
block.Title = title
return &RunChart{
Block: block,
lines: []TimeLine{},
timescale: calculateTimescale(refreshRateMs),
mutex: &sync.Mutex{},
scale: scale,
mode: ModeDefault,
legend: legend,
}
}
func (c *RunChart) newTimePoint(value float64) TimePoint {
now := time.Now()
return TimePoint{
value: value,
time: now,
coordinate: c.calculateTimeCoordinate(now),
}
}
func (c *RunChart) Draw(buffer *ui.Buffer) {
c.mutex.Lock()
c.Block.Draw(buffer)
c.grid = c.newChartGrid()
drawArea := image.Rect(
c.Inner.Min.X+c.grid.minTimeWidth+1, c.Inner.Min.Y,
c.Inner.Max.X, c.Inner.Max.Y-xAxisLabelsHeight-1,
)
c.renderAxes(buffer)
c.renderLines(buffer, drawArea)
c.renderLegend(buffer, drawArea)
c.mutex.Unlock()
}
func (c *RunChart) AddLine(Label string, color ui.Color) {
line := TimeLine{
points: []TimePoint{},
color: color,
label: Label,
extrema: ValueExtrema{max: -math.MaxFloat64, min: math.MaxFloat64},
}
c.lines = append(c.lines, line)
}
func (c *RunChart) ConsumeSample(sample data.Sample) {
float, err := strconv.ParseFloat(sample.Value, 64)
if err != nil {
// TODO visual notification + check sample.Error
}
c.mutex.Lock()
index := -1
for i, line := range c.lines {
if line.label == sample.Label {
index = i
}
}
line := c.lines[index]
if float < line.extrema.min {
line.extrema.min = float
}
if float > line.extrema.max {
line.extrema.max = float
}
line.points = append(line.points, c.newTimePoint(float))
c.lines[index] = line
// perform cleanup once in a while
if len(line.points)%100 == 0 {
c.trimOutOfRangeValues()
}
c.mutex.Unlock()
}
func (c *RunChart) renderLines(buffer *ui.Buffer, drawArea image.Rectangle) {
canvas := ui.NewCanvas()
canvas.Rectangle = drawArea
if len(c.lines) == 0 || len(c.lines[0].points) == 0 {
return
}
selectionCoordinate := c.calculateTimeCoordinate(c.selection)
selectionPoints := make(map[int]image.Point)
probe := c.lines[0].points[0]
delta := ui.AbsInt(c.calculateTimeCoordinate(probe.time) - probe.coordinate)
for i, line := range c.lines {
xPoint := make(map[int]image.Point)
xOrder := make([]int, 0)
// move selection on a delta, if it was instantiated after cursor move
if line.selectionCoordinate != 0 {
line.selectionCoordinate -= delta
c.lines[i].selectionCoordinate = line.selectionCoordinate
}
for j, timePoint := range line.points {
timePoint.coordinate -= delta
line.points[j] = timePoint
var y int
if c.grid.valueExtrema.max == c.grid.valueExtrema.min {
y = (drawArea.Dy() - 2) / 2
} else {
valuePerY := (c.grid.valueExtrema.max - c.grid.valueExtrema.min) / float64(drawArea.Dy()-2)
y = int(float64(timePoint.value-c.grid.valueExtrema.min) / valuePerY)
}
point := image.Pt(timePoint.coordinate, drawArea.Max.Y-y-1)
if _, exists := xPoint[point.X]; exists {
continue
}
if !point.In(drawArea) {
continue
}
if line.selectionCoordinate == 0 {
// instantiate selection coordinate as the closest point to the cursor time
if len(line.points) > j+1 && ui.AbsInt(timePoint.coordinate-selectionCoordinate) > ui.AbsInt(line.points[j+1].coordinate-selectionCoordinate) {
selectionPoints[i] = point
c.lines[i].selectionPoint = timePoint
}
} else if timePoint.coordinate == line.selectionCoordinate {
selectionPoints[i] = point
}
xPoint[point.X] = point
xOrder = append(xOrder, point.X)
}
for i, x := range xOrder {
currentPoint := xPoint[x]
var previousPoint image.Point
if i == 0 {
previousPoint = currentPoint
} else {
previousPoint = xPoint[xOrder[i-1]]
}
canvas.Line(
braillePoint(previousPoint),
braillePoint(currentPoint),
line.color,
)
}
}
canvas.Draw(buffer)
if c.mode == ModePinpoint {
for lineIndex, point := range selectionPoints {
buffer.SetCell(ui.NewCell(console.SymbolSelection, ui.NewStyle(c.lines[lineIndex].color)), point)
if c.lines[lineIndex].selectionCoordinate == 0 {
c.lines[lineIndex].selectionCoordinate = point.X
}
}
}
}
func (c *RunChart) trimOutOfRangeValues() {
minRangeTime := c.grid.timeRange.min.Add(-time.Minute * time.Duration(historyReserveMin))
for i, item := range c.lines {
lastOutOfRangeValueIndex := -1
for j, point := range item.points {
if point.time.Before(minRangeTime) {
lastOutOfRangeValueIndex = j
}
}
if lastOutOfRangeValueIndex > 0 {
item.points = append(item.points[:0], item.points[lastOutOfRangeValueIndex+1:]...)
c.lines[i] = item
}
}
}
func (c *RunChart) calculateTimeCoordinate(t time.Time) int {
timeDeltaWithGridMaxTime := c.grid.timeRange.max.Sub(t).Nanoseconds()
timeDeltaToPaddingRelation := float64(timeDeltaWithGridMaxTime) / float64(c.timescale.Nanoseconds())
return c.grid.maxTimeWidth - int(math.Ceil(float64(xAxisGridWidth)*timeDeltaToPaddingRelation))
}
// TODO add boundaries for values in range
func (c *RunChart) getMaxValueLength() int {
maxValueLength := 0
for _, line := range c.lines {
for _, point := range line.points {
l := len(formatValue(point.value, c.scale))
if l > maxValueLength {
maxValueLength = l
}
}
}
return maxValueLength
}
func (c *RunChart) MoveSelection(shift int) {
if c.mode == ModeDefault {
c.mode = ModePinpoint
c.selection = getMidRangeTime(c.grid.timeRange)
return
} else {
c.selection = c.selection.Add(c.grid.timePerPoint * time.Duration(shift))
if c.selection.After(c.grid.timeRange.max) {
c.selection = c.grid.timeRange.max
} else if c.selection.Before(c.grid.timeRange.min) {
c.selection = c.grid.timeRange.min
}
}
for i := range c.lines {
c.lines[i].selectionCoordinate = 0
}
}
func (c *RunChart) DisableSelection() {
if c.mode == ModePinpoint {
c.mode = ModeDefault
return
}
}
func getMidRangeTime(r TimeRange) time.Time {
delta := r.max.Sub(r.min)
return r.max.Add(-delta / 2)
}
func formatValue(value float64, scale int) string {
if math.Abs(value) == math.MaxFloat64 {
return "Inf"
} else {
format := "%." + strconv.Itoa(scale) + "f"
return fmt.Sprintf(format, value)
}
}
func formatValueWithSign(value float64, scale int) string {
if value == 0 {
return " 0"
} else if value > 0 {
return "+" + formatValue(value, scale)
} else {
return formatValue(value, scale)
}
}
// time duration between grid lines
func calculateTimescale(refreshRateMs int) time.Duration {
multiplier := refreshRateMs * xAxisGridWidth / 2
timescale := time.Duration(time.Millisecond * time.Duration(multiplier)).Round(time.Second)
if timescale.Seconds() == 0 {
return time.Second
} else {
return timescale
}
}
func braillePoint(point image.Point) image.Point {
return image.Point{X: point.X * xBrailleMultiplier, Y: point.Y * yBrailleMultiplier}
}