package tui

import (
	"io"
	"os"
	"sync"

	"golang.org/x/term"
)

var (
	lock     = sync.Mutex{}
	t        *term.Terminal
	oldState *term.State
)

func Start() {
	lock.Lock()
	defer lock.Unlock()
	if t != nil {
		return
	}

	screen := struct {
		io.Reader
		io.Writer
	}{os.Stdin, os.Stdout}

	var err error
	oldState, err = term.MakeRaw(int(os.Stdin.Fd()))
	if err != nil {
		panic(err)
	}

	t = term.NewTerminal(screen, "")
	t.SetSize(80, 24)
}

func Stop() {
	lock.Lock()
	defer lock.Unlock()
	if t == nil {
		return
	}

	term.Restore(int(os.Stdin.Fd()), oldState)
	t = nil
	oldState = nil
}