Files
terminal/tui/field.go
T

116 lines
3.2 KiB
Go

package tui
import (
"github.com/lixenwraith/terminal"
)
// Focus is a focus ring over a form's controls, numbered 0 to Len-1
type Focus struct {
Index, Len int
}
// HandleKey moves focus on Tab and Shift+Tab, wrapping, and reports whether
// it moved
func (f *Focus) HandleKey(key terminal.Key, mod terminal.Modifier) bool {
if f.Len < 1 {
return false
}
switch {
case key == terminal.KeyTab && mod&terminal.ModShift == 0:
f.Index = (f.Index + 1) % f.Len
case key == terminal.KeyTab || key == terminal.KeyBacktab:
f.Index = (f.Index - 1 + f.Len) % f.Len
default:
return false
}
return true
}
// Field labels one form row
type Field struct {
Label string
Required bool
Help string // shown under the field while it has focus
Error string // shown under the field, in place of Help
}
// Field draws a form row at y: the focus mark, the label in a column labelW
// wide with the required mark, and below, the error, or the help while
// focused. It returns the region for the value beside the label, where the
// caller draws a TextInput, Choice or Toggle, and the rows it used.
func (r Region) Field(y, labelW int, f Field, focused bool, th Theme) (Region, int) {
label := th.Muted
if focused {
label = th.Text
r.TextStyled(0, y, string(th.Glyphs.Focus), th.Accent)
}
name := f.Label
if f.Required {
name = Truncate(name, labelW-2)
r.TextStyled(2+RuneLen(name)+1, y, string(th.Glyphs.Required), th.Accent)
}
r.TextStyled(2, y, Truncate(name, labelW), label)
x := 2 + labelW + 1
note, style := f.Error, th.Error
if note == "" && focused {
note, style = f.Help, th.Muted
}
if note == "" {
return r.Sub(x, y, r.W-x, 1), 1
}
r.TextStyled(x, y+1, Truncate(note, r.W-x), style)
return r.Sub(x, y, r.W-x, 1), 2
}
// TextInput draws state's text on r's first row, or, empty, the placeholder
// muted: a default shows what an empty value means. Focused, it draws on the
// Input background with the cursor, scrolling to keep the cursor in view.
func (r Region) TextInput(state *TextFieldState, placeholder string, focused bool, th Theme) {
if r.W < 1 || r.H < 1 {
return
}
var bg Style
if focused {
bg = th.Input
}
state.AdjustScroll(r.W)
text, style := []rune(placeholder), th.Muted.On(bg)
if len(state.Text) > 0 {
text, style = state.Text[state.Scroll:], th.Text.On(bg)
}
for x := 0; x < r.W; x++ {
ch := ' '
if x < len(text) {
ch = text[x]
}
r.Cell(x, 0, ch, style.Fg, style.Bg, style.Attr)
}
if focused {
x, ch := state.Cursor-state.Scroll, ' '
if x < len(text) {
ch = text[x]
}
r.Cell(x, 0, ch, th.Cursor.Fg, th.Cursor.Bg, th.Cursor.Attr)
}
}
// Group draws a foldable group's header at y: the focus mark, the Folded or
// Unfolded glyph and the title, and while folded, a muted summary of what
// it holds
func (r Region) Group(y int, title, summary string, open, focused bool, th Theme) {
mark, style := th.Glyphs.Folded, th.Muted
if open {
mark = th.Glyphs.Unfolded
}
if focused {
style = th.Text
r.TextStyled(0, y, string(th.Glyphs.Focus), th.Accent)
}
r.TextStyled(2, y, string(mark)+" "+title, style)
if !open && summary != "" {
x := 2 + 2 + RuneLen(title) + 2
r.TextStyled(x, y, Truncate(summary, r.W-x), th.Muted)
}
}