tui/views/view_constrain.go

package views

import (
	"git.milar.in/milarin/gmath"
	"git.milar.in/milarin/tui"
)

// ConstrainView is a tui.Wrapper which constrains the dimensions of its View
type ConstrainView struct {
	tui.WrapperTmpl
	MaxWidth  int
	MaxHeight int
}

var _ tui.Wrapper = &ConstrainView{}

func NewConstrainView(view tui.View, maxWidth, maxHeight int) *ConstrainView {
	v := new(ConstrainView)
	v.SetView(view)
	v.Constrain(maxWidth, maxHeight)
	return v
}

func (v *ConstrainView) Constrain(maxWidth, maxHeight int) {
	v.MaxWidth, v.MaxHeight = maxWidth, maxHeight
}

func (v *ConstrainView) Layout() (prefWidth, prefHeight int) {
	if v.View() == nil {
		return v.MaxWidth, v.MaxHeight
	}

	vw, vh := v.View().Layout()
	prefWidth = iff(vw >= 0, gmath.Min(vw, v.MaxWidth), v.MaxWidth)
	prefHeight = iff(vh >= 0, gmath.Min(vh, v.MaxHeight), v.MaxHeight)
	return
}