/*
Copyright © 2020 NAME HERE <EMAIL ADDRESS>

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package cmd

import (
	"fmt"
	"it2000.com.cn/tele-recv/utils"
	"log"
	"os"
	"os/signal"
	"syscall"

	"github.com/spf13/cobra"
)

// startCmd represents the start command
var startCmd = &cobra.Command{
	Use:   "start",
	Short: "A brief description of your command",
	Long: `A longer description that spans multiple lines and likely contains examples
and usage of using your command. For example:

Cobra is a CLI library for Go that empowers applications.
This application is a tool to generate the needed files
to quickly create a Cobra application.`,
	Run: start,
}

var run bool

func init() {
	rootCmd.AddCommand(startCmd)

	// Here you will define your flags and configuration settings.

	// Cobra supports Persistent Flags which will work for this command
	// and all subcommands, e.g.:
	// startCmd.PersistentFlags().String("foo", "", "A help for foo")

	// Cobra supports local flags which will only run when this command
	// is called directly, e.g.:
	// startCmd.Flags().BoolP("toggle", "t", false, "Help message for toggle")
}


func start(cmd *cobra.Command, args []string){
	// Go signal notification works by sending `os.Signal`
	// values on a channel. We'll create a channel to
	// receive these notifications (we'll also make one to
	// notify us when the program can exit).
	sigs := make(chan os.Signal, 1)
	done := make(chan bool, 1)

	// `signal.Notify` registers the given channel to
	// receive notifications of the specified signals.
	signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
	run = true

	// This goroutine executes a blocking receive for
	// signals. When it gets one it'll print it out
	// and then notify the program that it can finish.
	go func() {
		sig := <-sigs
		fmt.Println()
		fmt.Println(sig)
		run = false
		done <- true
	}()

	// The program will wait here until it gets the
	// expected signal (as indicated by the goroutine
	// above sending a value on `done`) and then exit.
	fmt.Println("awaiting signal")
	for run {
		if !utils.IsPortOpen() {
			log.Println("try to open port")
			err := utils.OpenPort(device, baudrate, bytesize)
			if err != nil {
				log.Fatal("error in open serial port ", err)
			}
			log.Println("starting read")
		}
		buffer, count := utils.ReadPort()
		if count > 0 {
			log.Print(string(buffer))
		}
	}
	<-done
	fmt.Println("exiting")

}