lipgloss/align.go
2024-05-15 14:59:47 -04:00

84 lines
2.1 KiB
Go

package lipgloss
import (
"strings"
"github.com/charmbracelet/x/ansi"
"github.com/muesli/termenv"
)
// Perform text alignment. If the string is multi-lined, we also make all lines
// the same width by padding them with spaces. If a termenv style is passed,
// use that to style the spaces added.
func alignTextHorizontal(str string, pos Position, width int, style *termenv.Style) string {
lines, widestLine := getLines(str)
var b strings.Builder
for i, l := range lines {
lineWidth := ansi.StringWidth(l)
shortAmount := widestLine - lineWidth // difference from the widest line
shortAmount += max(0, width-(shortAmount+lineWidth)) // difference from the total width, if set
if shortAmount > 0 {
switch pos { //nolint:exhaustive
case Right:
s := strings.Repeat(" ", shortAmount)
if style != nil {
s = style.Styled(s)
}
l = s + l
case Center:
// Note: remainder goes on the right.
left := shortAmount / 2 //nolint:gomnd
right := left + shortAmount%2 //nolint:gomnd
leftSpaces := strings.Repeat(" ", left)
rightSpaces := strings.Repeat(" ", right)
if style != nil {
leftSpaces = style.Styled(leftSpaces)
rightSpaces = style.Styled(rightSpaces)
}
l = leftSpaces + l + rightSpaces
default: // Left
s := strings.Repeat(" ", shortAmount)
if style != nil {
s = style.Styled(s)
}
l += s
}
}
b.WriteString(l)
if i < len(lines)-1 {
b.WriteRune('\n')
}
}
return b.String()
}
func alignTextVertical(str string, pos Position, height int, _ *termenv.Style) string {
strHeight := strings.Count(str, "\n") + 1
if height < strHeight {
return str
}
switch pos {
case Top:
return str + strings.Repeat("\n", height-strHeight)
case Center:
topPadding, bottomPadding := (height-strHeight)/2, (height-strHeight)/2 //nolint:gomnd
if strHeight+topPadding+bottomPadding > height {
topPadding--
} else if strHeight+topPadding+bottomPadding < height {
bottomPadding++
}
return strings.Repeat("\n", topPadding) + str + strings.Repeat("\n", bottomPadding)
case Bottom:
return strings.Repeat("\n", height-strHeight) + str
}
return str
}