package main

import (
	"encoding/binary"
	"encoding/json"
	"flag"
	"fmt"
	"net"
	"os"
	"io"
)

type CommandMap struct {
	Type		string `json:"Type"`
	Endpoint	string `json:"Endpoint"`
}

type RunningInstance struct {
	Endpoint		string `json:"endpoint"`
	Software		string `json:"software"`
	Min_id			string
	Status			int `json:"status"`
}

type ResponseBack struct {
	Type			string `json:"Type"`
	Message			string `json:"Message"`
	RunningInstances	[]RunningInstance `json:"RunningInstances"`
}

func main() {

	shutdownPtr := flag.Bool("shutdown", false, "Shutdown server")
	suspendinstancePtr := flag.String("suspend-instance", "", "Instance to Suspend")
	resumeinstancePtr := flag.String("resume-instance", "", "Instance to Resume")
	addinstancePtr := flag.String("add-instance", "", "Instance to add")
	statusPtr := flag.Bool("status", false, "Check status")
//	usernamePtr := flag.String("username", "", "Set username")
//	passwordPtr := flag.String("password", "", "Set password")
	flag.Parse()

	/* Condition verification */
	totalflags := 0
	var commandMap CommandMap
	var responseback ResponseBack

	if *shutdownPtr == true {
		totalflags++
		commandMap.Type = "shutdown"
	}
	if *statusPtr == true {
		totalflags++
		commandMap.Type = "status"
	}
	if *addinstancePtr != "" {
		totalflags++
		commandMap.Type = "add"
		commandMap.Endpoint = *addinstancePtr
	}
	if *suspendinstancePtr != "" {
		totalflags++
		commandMap.Type = "suspend"
	}
	if *resumeinstancePtr != "" {
		totalflags++
		commandMap.Type = "resume"
	}
	if totalflags > 1 {
		fmt.Println("Incompatible arguments, exiting.")
		os.Exit(1)
	} else if totalflags == 0 {
		fmt.Println("No options specified, exiting.")
		os.Exit(1)
	}

	commandByte, err := json.Marshal(commandMap)
	if err != nil {
		fmt.Println(err)
		return
	}
	c, err := net.Dial("tcp", "127.0.0.1:5555")
	if err != nil {
		fmt.Println(err)
		return
	}
	sizebytes := make([]byte, 4)
	b := len(commandByte)

	// Send the request
	binary.LittleEndian.PutUint32(sizebytes, uint32(b))
	c.Write(sizebytes)
	c.Write(commandByte)

	// Read the response
	n, err := io.ReadFull(c, sizebytes)
	if err != nil || n != 4 {
		fmt.Println("err", err, n)
	}
	jsonsize := int(binary.LittleEndian.Uint32(sizebytes))
	responsebytes := make([]byte, jsonsize)
	n, err = io.ReadFull(c, responsebytes)
	err = json.Unmarshal(responsebytes, &responseback)
	if err != nil {
		fmt.Println("Unmarshal error", err)
	}

	switch commandMap.Type {
	case "add":
		fmt.Println("Add instance")
	case "status":
		fmt.Println("Status:" + responseback.Message)
		for x, runninginstance := range responseback.RunningInstances {
			fmt.Println("ID:", x, runninginstance.Endpoint, runninginstance.Status)
		}
	}
}