tui/views/view_margin.go

package views

import "git.milar.in/milarin/tui"

// MarginView is a tui.Wrapper which applies margin around its view
type MarginView struct {
	tui.WrapperTmpl
	Margin map[tui.Side]int
}

var _ tui.Wrapper = &MarginView{}

func NewMarginView(view tui.View, top, right, bottom, left int) *MarginView {
	v := new(MarginView)
	v.SetView(view)
	v.SetMargin(top, right, bottom, left)
	return v
}

func (g *MarginView) Draw(buf *tui.ViewBuffer) {
	x := g.Margin[tui.SideLeft]
	y := g.Margin[tui.SideTop]
	w := buf.Width() - x - g.Margin[tui.SideRight]
	h := buf.Height() - y - g.Margin[tui.SideBottom]

	g.ViewTmpl.Draw(buf)
	g.View().Draw(buf.Sub(x, y, w, h))
}

func (v *MarginView) Layout() (prefWidth, prefHeight int) {
	w, h := v.View().Layout()
	w = iff(w > 0, w+v.Margin[tui.SideLeft]+v.Margin[tui.SideRight], w)
	h = iff(h > 0, h+v.Margin[tui.SideTop]+v.Margin[tui.SideBottom], h)
	return w, h
}

func (v *MarginView) SetMargin(top, right, bottom, left int) {
	v.Margin = map[tui.Side]int{
		tui.SideTop:    top,
		tui.SideRight:  right,
		tui.SideBottom: bottom,
		tui.SideLeft:   left,
	}
}