package main

import "log"
import "os"
import "time"
import "net"
import "fmt"
import "bufio"

import "github.com/svent/go-nbreader"

import "git.wit.com/jcarr/dnssecsocket"

// import "github.com/gookit/config"
// import "git.wit.com/wit/gui"

// import "github.com/davecgh/go-spew/spew"

// reminder to use this for JSON
// https://github.com/tidwall/gjson
//   value := gjson.Get(json, "name.last")
//   println(value.String())
//   value := gjson.Get(json, friends.#[last=="Murphy"].first)

// use mergo to merge structs
// import "github.com/imdario/mergo"
// mergo.Merge(&dest, src)

// always sorted slice (new project)
// https://github.com/yaa110/sslice

const (
	CONN_HOST = "v000185.testing.com.customers.wprod.wit.com"
	CONN_PORT = "3333"
	CONN_PROTO = "tcp"
)

func socketToWIT(myhostname string) {
	remoteAddr :=  CONN_HOST + ":" + CONN_PORT
	log.Println("remoteAddr:", remoteAddr)

	localTCPAddr := dnssecsocket.ResolveIPv6hostname(myhostname)
	remoteTCPAddr, err := net.ResolveTCPAddr("tcp", remoteAddr)

	// connect to this socket
	conn, err := net.DialTCP(CONN_PROTO, localTCPAddr, remoteTCPAddr)

	if err != nil {
		log.Println(CONN_HOST, CONN_PORT, CONN_PROTO)
		log.Println(err)
		log.Println("socket connect failed. Not sure what to do here. os.Exit() ?")
		return
	}
	defer conn.Close()

	log.Println("socket connected to", CONN_PROTO, CONN_HOST, CONN_PORT)

	tmp, err := conn.Write([]byte(string(myhostname + "\n")))
	log.Println("conn.Write:", tmp, err)

	connStdin, _ := conn.File()

	go nonBlockingReader(connStdin, os.Stdout)

	// read in input from stdin
	reader := bufio.NewReader(os.Stdin)
	for {
		// read in the command to send to our server
		fmt.Print("Text to send: ")
		text, _ := reader.ReadString('\n')

		// send the command over the socket socket
		a, err := conn.Write([]byte(string(text + "\n")))

		// a, err := connStdin.Write([]byte(string(text + "\n")))
		if (err != nil) {
			fmt.Println("SOCKET DIED with err=", err, a)
			return
		}
	}
}

func retrySocket() {
	for {
		log.Println("Sleep for 3 seconds, then try to establish connection to WIT")
		time.Sleep(3 * 1000 * 1000 * 1000)

		// for now, loop until I figure out what to actually do
		socketToWIT("librem15.lab.wit.com")
	}
}

// pass in two file handles (1 read, 1 write)
func nonBlockingReader(readFileHandle *os.File, writeFileHandle *os.File) {
	// create a nonblocking GO reader
	newreader := bufio.NewReader(readFileHandle)
        nbr := nbreader.NewNBReader(newreader, 1024)

	for {
		defer readFileHandle.Close()
		defer writeFileHandle.Close()
		totalCount := 0
		for {
			oneByte := make([]byte, 1024)
			count, err := nbr.Read(oneByte)
			if (err != nil) {
				log.Println("count, err =", count, err)
				return
			}
			totalCount += count
			if (count == 0) {
				time.Sleep(20 * time.Millisecond)   // only check the buffer 500 times a second
				if (totalCount != 0) {
					log.Println("totalCount = ", totalCount)
					totalCount = 0
				}
			}
			writeFileHandle.Write([]byte(string(oneByte)))
		}
	}
}