feat: expand component library with bar chart, content cards, and layout helpers

Add BarChart component that renders multi-row Unicode bar charts with
anchored Y-axis labels, automatic tick-step computation, sub-sampling
for narrow terminals, and optional X-axis date labels. The chart
gracefully degrades to a sparkline when width/height is too small.

Add ContentCard, CardRow, and CardInnerWidth utilities for consistent
bordered card layout across all dashboard tabs. ContentCard renders
a lipgloss-bordered card with optional bold title; CardRow joins
pre-rendered cards horizontally; CardInnerWidth computes the usable
text width after accounting for border and padding.

Add LayoutRow helper that distributes a total width into n integer
widths that sum exactly, absorbing the integer-division remainder
into the first items -- eliminates off-by-one pixel drift in multi-
column layouts.

Refactor MetricCard to accept an outerWidth parameter and derive the
content width internally by subtracting border, replacing the old
raw-width parameter that required callers to do the subtraction.
MetricCardRow now uses LayoutRow for exact width distribution.

Refine TabBar to render all tabs on a single row when they fit within
the terminal width, falling back to the two-row layout only when
they overflow.

Simplify StatusBar by removing the unused filterInfo append that was
cluttering the left section.
This commit is contained in:
teernisse
2026-02-19 13:02:59 -05:00
parent 79ab17488e
commit 4d46977328
3 changed files with 337 additions and 15 deletions

View File

@@ -2,20 +2,46 @@ package components
import (
"fmt"
"math"
"strings"
"cburn/internal/tui/theme"
"github.com/charmbracelet/lipgloss"
)
// LayoutRow distributes totalWidth into n widths that sum to exactly totalWidth.
// First items absorb the remainder from integer division.
func LayoutRow(totalWidth, n int) []int {
if n <= 0 {
return nil
}
base := totalWidth / n
remainder := totalWidth % n
widths := make([]int, n)
for i := range widths {
widths[i] = base
if i < remainder {
widths[i]++
}
}
return widths
}
// MetricCard renders a small metric card with label, value, and delta.
func MetricCard(label, value, delta string, width int) string {
// outerWidth is the total rendered width including border.
func MetricCard(label, value, delta string, outerWidth int) string {
t := theme.Active
contentWidth := outerWidth - 2 // subtract border
if contentWidth < 10 {
contentWidth = 10
}
cardStyle := lipgloss.NewStyle().
Border(lipgloss.RoundedBorder()).
BorderForeground(t.Border).
Width(width).
Width(contentWidth).
Padding(0, 1)
labelStyle := lipgloss.NewStyle().
@@ -38,24 +64,69 @@ func MetricCard(label, value, delta string, width int) string {
}
// MetricCardRow renders a row of metric cards side by side.
// totalWidth is the full row width; cards sum to exactly that.
func MetricCardRow(cards []struct{ Label, Value, Delta string }, totalWidth int) string {
if len(cards) == 0 {
return ""
}
cardWidth := (totalWidth - len(cards) - 1) / len(cards)
if cardWidth < 10 {
cardWidth = 10
}
widths := LayoutRow(totalWidth, len(cards))
var rendered []string
for _, c := range cards {
rendered = append(rendered, MetricCard(c.Label, c.Value, c.Delta, cardWidth))
for i, c := range cards {
rendered = append(rendered, MetricCard(c.Label, c.Value, c.Delta, widths[i]))
}
return lipgloss.JoinHorizontal(lipgloss.Top, rendered...)
}
// ContentCard renders a bordered content card with an optional title.
// outerWidth controls the total rendered width including border.
func ContentCard(title, body string, outerWidth int) string {
t := theme.Active
contentWidth := outerWidth - 2 // subtract border chars
if contentWidth < 10 {
contentWidth = 10
}
cardStyle := lipgloss.NewStyle().
Border(lipgloss.RoundedBorder()).
BorderForeground(t.Border).
Width(contentWidth).
Padding(0, 1)
titleStyle := lipgloss.NewStyle().
Foreground(t.TextMuted).
Bold(true)
content := ""
if title != "" {
content = titleStyle.Render(title) + "\n"
}
content += body
return cardStyle.Render(content)
}
// CardRow joins pre-rendered card strings horizontally.
func CardRow(cards []string) string {
if len(cards) == 0 {
return ""
}
return lipgloss.JoinHorizontal(lipgloss.Top, cards...)
}
// CardInnerWidth returns the usable text width inside a ContentCard
// given its outer width (subtracts border + padding).
func CardInnerWidth(outerWidth int) int {
w := outerWidth - 4 // 2 border + 2 padding
if w < 10 {
w = 10
}
return w
}
// Sparkline renders a unicode sparkline from values.
func Sparkline(values []float64, color lipgloss.Color) string {
if len(values) == 0 {
@@ -91,6 +162,255 @@ func Sparkline(values []float64, color lipgloss.Color) string {
return style.Render(result)
}
// BarChart renders a multi-row bar chart with anchored Y-axis and optional X-axis labels.
// labels (if non-nil) should correspond 1:1 with values for x-axis display.
// height is a target; actual height adjusts slightly so Y-axis ticks are evenly spaced.
func BarChart(values []float64, labels []string, color lipgloss.Color, width, height int) string {
if len(values) == 0 {
return ""
}
if width < 15 || height < 3 {
return Sparkline(values, color)
}
t := theme.Active
// Find max value
maxVal := 0.0
for _, v := range values {
if v > maxVal {
maxVal = v
}
}
if maxVal == 0 {
maxVal = 1
}
// Y-axis: compute tick step and ceiling, then fit within requested height.
// Each interval needs at least 2 rows for readable spacing, so
// maxIntervals = height/2. If the initial step gives too many intervals,
// double it until they fit.
tickStep := chartTickStep(maxVal)
maxIntervals := height / 2
if maxIntervals < 2 {
maxIntervals = 2
}
for {
n := int(math.Ceil(maxVal / tickStep))
if n <= maxIntervals {
break
}
tickStep *= 2
}
ceiling := math.Ceil(maxVal/tickStep) * tickStep
numIntervals := int(math.Round(ceiling / tickStep))
if numIntervals < 1 {
numIntervals = 1
}
// Each interval gets the same number of rows; chart height is an exact multiple.
rowsPerTick := height / numIntervals
if rowsPerTick < 2 {
rowsPerTick = 2
}
chartH := rowsPerTick * numIntervals
// Pre-compute tick labels at evenly-spaced row positions
yLabelW := len(formatChartLabel(ceiling)) + 1
if yLabelW < 4 {
yLabelW = 4
}
tickLabels := make(map[int]string)
for i := 1; i <= numIntervals; i++ {
row := i * rowsPerTick
tickLabels[row] = formatChartLabel(tickStep * float64(i))
}
// Chart area width (excluding y-axis label and axis line char)
chartW := width - yLabelW - 1
if chartW < 5 {
chartW = 5
}
n := len(values)
// Bar sizing: always use 1-char gaps, target barW >= 2.
// If bars don't fit at width 2, subsample to fewer bars.
gap := 1
if n <= 1 {
gap = 0
}
barW := 2
if n > 1 {
barW = (chartW - (n - 1)) / n
} else if n == 1 {
barW = chartW
}
if barW < 2 && n > 1 {
// Subsample so bars fit at width 2 with 1-char gaps
maxN := (chartW + 1) / 3 // each bar = 2 chars + 1 gap (last bar no gap)
if maxN < 2 {
maxN = 2
}
sampled := make([]float64, maxN)
var sampledLabels []string
if len(labels) == n {
sampledLabels = make([]string, maxN)
}
for i := range sampled {
srcIdx := i * (n - 1) / (maxN - 1)
sampled[i] = values[srcIdx]
if sampledLabels != nil {
sampledLabels[i] = labels[srcIdx]
}
}
values = sampled
labels = sampledLabels
n = maxN
barW = 2
}
if barW > 6 {
barW = 6
}
axisLen := n*barW + max(0, n-1)*gap
blocks := []rune{' ', '▁', '▂', '▃', '▄', '▅', '▆', '▇', '█'}
barStyle := lipgloss.NewStyle().Foreground(color)
axisStyle := lipgloss.NewStyle().Foreground(t.TextDim)
var b strings.Builder
// Render rows top to bottom using chartH (aligned to tick intervals)
for row := chartH; row >= 1; row-- {
rowTop := ceiling * float64(row) / float64(chartH)
rowBottom := ceiling * float64(row-1) / float64(chartH)
label := tickLabels[row]
b.WriteString(axisStyle.Render(fmt.Sprintf("%*s", yLabelW, label)))
b.WriteString(axisStyle.Render("│"))
for i, v := range values {
if i > 0 && gap > 0 {
b.WriteString(strings.Repeat(" ", gap))
}
if v >= rowTop {
b.WriteString(barStyle.Render(strings.Repeat("█", barW)))
} else if v > rowBottom {
frac := (v - rowBottom) / (rowTop - rowBottom)
idx := int(frac * 8)
if idx > 8 {
idx = 8
}
if idx < 1 {
idx = 1
}
b.WriteString(barStyle.Render(strings.Repeat(string(blocks[idx]), barW)))
} else {
b.WriteString(strings.Repeat(" ", barW))
}
}
b.WriteString("\n")
}
// X-axis line with 0 label
b.WriteString(axisStyle.Render(fmt.Sprintf("%*s", yLabelW, "0")))
b.WriteString(axisStyle.Render("└"))
b.WriteString(axisStyle.Render(strings.Repeat("─", axisLen)))
// X-axis labels
if len(labels) == n && n > 0 {
buf := make([]byte, axisLen)
for i := range buf {
buf[i] = ' '
}
// Place labels at bar start positions, skip overlaps
minSpacing := 8
labelStep := max(1, (n*minSpacing)/(axisLen+1))
lastEnd := -1
for i := 0; i < n; i += labelStep {
pos := i * (barW + gap)
lbl := labels[i]
end := pos + len(lbl)
if pos <= lastEnd {
continue
}
if end > axisLen {
end = axisLen
if end-pos < 3 {
continue
}
lbl = lbl[:end-pos]
}
copy(buf[pos:end], lbl)
lastEnd = end + 1
}
// Always place the last label, right-aligned to axis edge if needed.
// Overwrites any truncated label underneath.
if n > 1 && len(labels[n-1]) <= axisLen {
lbl := labels[n-1]
pos := axisLen - len(lbl)
end := axisLen
// Clear the area first in case a truncated label is there
for j := pos; j < end; j++ {
buf[j] = ' '
}
copy(buf[pos:end], lbl)
}
b.WriteString("\n")
b.WriteString(strings.Repeat(" ", yLabelW+1))
b.WriteString(axisStyle.Render(strings.TrimRight(string(buf), " ")))
}
return b.String()
}
// chartTickStep computes a nice tick interval targeting ~5 ticks.
func chartTickStep(maxVal float64) float64 {
if maxVal <= 0 {
return 1
}
rough := maxVal / 5
exp := math.Floor(math.Log10(rough))
base := math.Pow(10, exp)
frac := rough / base
switch {
case frac < 1.5:
return base
case frac < 3.5:
return 2 * base
default:
return 5 * base
}
}
func formatChartLabel(v float64) string {
switch {
case v >= 1e9:
if v == math.Trunc(v/1e9)*1e9 {
return fmt.Sprintf("%.0fB", v/1e9)
}
return fmt.Sprintf("%.1fB", v/1e9)
case v >= 1e6:
if v == math.Trunc(v/1e6)*1e6 {
return fmt.Sprintf("%.0fM", v/1e6)
}
return fmt.Sprintf("%.1fM", v/1e6)
case v >= 1e3:
if v == math.Trunc(v/1e3)*1e3 {
return fmt.Sprintf("%.0fk", v/1e3)
}
return fmt.Sprintf("%.1fk", v/1e3)
case v >= 1:
return fmt.Sprintf("%.0f", v)
default:
return fmt.Sprintf("%.2f", v)
}
}
// ProgressBar renders a colored progress bar.
func ProgressBar(pct float64, width int) string {
t := theme.Active