package main

import (
	"fmt"

	"github.com/jroimartin/gocui"
)

func main() {
	g, err := gocui.NewGui(gocui.OutputNormal)
	if err != nil {
		panic(err)
	}
	defer g.Close()

	g.SetManagerFunc(layout)

	if err := g.SetKeybinding("", gocui.KeyCtrlC, gocui.ModNone, quit); err != nil {
		panic(err)
	}

	if err := g.SetKeybinding("version", gocui.KeyEnter, gocui.ModNone, version); err != nil {
		panic(err)
	}

	if err := g.MainLoop(); err != nil && err != gocui.ErrQuit {
		panic(err)
	}

}

func version(g *gocui.Gui, v *gocui.View) error {
	if v, err := g.SetView("version", 0, 0, 100, 30); err != nil {
		if err != gocui.ErrUnknownView {
			return err
		}
		fmt.Fprintln(v, "v0.1")
	}
	return nil
}

func layout(g *gocui.Gui) error {
	g.Cursor = true
	g.Mouse = true
	maxX, maxY := g.Size()
	if v, err := g.SetView("hello", maxX/2-7, maxY/2, maxX/2+7, maxY/2+2); err != nil {
		if err != gocui.ErrUnknownView {
			return err
		}
		fmt.Fprintln(v, "Hello world!")
	}
	if v, err := g.SetView("version", -2, maxY-2, maxX, maxY); err != nil {
		if err != gocui.ErrUnknownView {
			return err
		}
		fmt.Fprintln(v, "\tversion 0.1")
	}
	return nil
}

func quit(g *gocui.Gui, v *gocui.View) error {
	return gocui.ErrQuit
}