package main

import (
	"image"

	"gioui.org/ui"
	"gioui.org/ui/app"
	"gioui.org/ui/f32"
	"gioui.org/ui/layout"
	"gioui.org/ui/paint"

	gio "git.wow.st/gmp/giowrap"
)

func main() {
	go func() {
		w := app.NewWindow()
		ops := new(ui.Ops)
		gcs := make([]gio.GridChild, 0)

		for e := range w.Events() {
			if e, ok := e.(app.UpdateEvent); ok {
				ops.Reset()
				c := &e.Config
				cs := layout.RigidConstraints(e.Size)
				nrows := 5
				ncols := 10
				grid := gio.Grid{Cols: ncols}
				cs = grid.Init(ops, cs)

				for i := 0; i < nrows*ncols; i++ {
					grid.Begin()
					dims := layoutRect(c, ops, cs)
					gcs = append(gcs, grid.End(dims))
				}

				grid.Layout(gcs...)
				w.Update(ops)
				gcs = gcs[0:0]
			}
		}
	}()
	app.Main()
}

func layoutRect(c ui.Config, ops *ui.Ops, cs layout.Constraints) layout.Dimensions {
	ins := layout.UniformInset(ui.Px(10))
	cs = ins.Begin(c, ops, cs)
	paint.PaintOp{Rect: f32.Rectangle{
		Max: f32.Point{
			X: float32(cs.Width.Max),
			Y: float32(cs.Width.Max),
		},
	}}.Add(ops)
	dims := layout.Dimensions{
		Size: image.Point{
			X: cs.Width.Max,
			Y: cs.Width.Max,
		},
	}
	return ins.End(dims)
}