package manager

import (
	"bufio"
	"context"
	"encoding/json"
	"fmt"
	"log"
	"time"

	"git.godopu.net/lab/etri-smartfarm-poc-controller-serial/puserial"
	"github.com/jacobsa/go-serial/serial"
	"github.com/rjeczalik/notify"
)

var ctx context.Context
var cancel context.CancelFunc
var ch_discover chan notify.EventInfo
var _managerObj *_manager

func init() {
	ctx, cancel = context.WithCancel(context.Background())
	ch_discover = make(chan notify.EventInfo)
	_managerObj = &_manager{
		devices:      map[string]*_device{},
		SyncListener: nil,
		RecvListener: nil,
	}
}

func Close() {
	cancel()
}

func register(iface string) {
	fmt.Println("Handle] ", iface)

	// change permission
	err := ChangePermission(iface)
	if err != nil {
		panic(err)
	}

	// Set up options.
	options := serial.OpenOptions{
		PortName:        iface,
		BaudRate:        9600,
		DataBits:        8,
		StopBits:        1,
		MinimumReadSize: 16,
	}

	// Open the port.
	port, err := serial.Open(options)
	if err != nil {
		log.Fatalf("serial.Open: %v", err)
	}

	// Make sure to close it later.
	defer port.Close()
	reader := bufio.NewReader(port)
	dev := &_device{}

	for {
		b, _, _ := reader.ReadLine()

		err := json.Unmarshal(b, &dev)

		if err != nil {
			continue
		}

		fmt.Println(dev)
		port.Write([]byte{200})
		time.Sleep(time.Second)
		break
	}

	// var data string
}

func Run() error {
	iface, err := puserial.InitDevice()
	if err != nil {
		if err.Error() != "USB Not found" {
			return err
		}
	} else {
		// _managerObj.onAdd(iface)
		register(iface)
	}

	go puserial.WatchNewDevice(ctx, ch_discover)

	for {
		e, ok := <-ch_discover
		if !ok {
			log.Println("manager exit")
			return nil
		}
		register(e.Path())
	}
}