package main

import (
	"fmt"
	"github.com/jroimartin/gocui"
	"log"
)

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

	g.SetManagerFunc(layout)
	g.Mouse = true
	g.Cursor = true
	initKeybindings(g)

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

var (
	playerX int = 0
	playerY int = 0
)

func layout(g *gocui.Gui) error {

	maxX, maxY := g.Size()
	if player, err := g.SetView("player", maxX/2+7+playerX, maxY/2+2-playerY, maxX/2+9+playerX, maxY/2+4-playerY); err != nil {
		if err != gocui.ErrUnknownView {
			return err
		}
		player.Frame = false
		player.BgColor = gocui.ColorRed
		fmt.Fprintln(player, "@")
	}

	return nil
}

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

func initKeybindings(g *gocui.Gui) error {

	var movementStep int = 1

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

	if err := g.SetKeybinding("", 'a', gocui.ModNone,
		func(g *gocui.Gui, v *gocui.View) error {
			playerX -= movementStep
			return nil
		}); err != nil {
		log.Panicln(err)
	}

	if err := g.SetKeybinding("", 'd', gocui.ModNone,
		func(g *gocui.Gui, v *gocui.View) error {
			playerX += movementStep
			return nil
		}); err != nil {
		log.Panicln(err)
	}

	if err := g.SetKeybinding("", 'w', gocui.ModNone,
		func(g *gocui.Gui, v *gocui.View) error {
			playerY += movementStep
			return nil
		}); err != nil {
		log.Panicln(err)
	}

	if err := g.SetKeybinding("", 's', gocui.ModNone,
		func(g *gocui.Gui, v *gocui.View) error {
			playerY -= movementStep
			return nil
		}); err != nil {
		log.Panicln(err)
	}

	return nil
}