package main

import (
	"bufio"
	"fmt"
	"os"
	"time"
	"iptcp/pkg/ipstack"
	"strings"
	
)

func SendUpdates() {
	myInterfaces := ipstack.GetInterfaces()
	myNeighbors := ipstack.GetNeighbors()
	for _, iface := range myInterfaces {
		// send RIP updates to all neighbors
		for _, _ = range myNeighbors {
			// iface.udp.Write(neighbor, data)
			// iface.RecvSocket.Write(neighbor, data)
			// wait for response for 12 seconds
			response := make([]byte, 512)
			iface.RecvSocket.Read(response)
			time.Sleep(12 * time.Second)
			if len(response) == 0 {
				// ipstack.RemoveNeighbor(neighbor)
			}
		}
	}
	time.Sleep(5 * time.Second)
}

func main() {
	if len(os.Args) != 2 {
		fmt.Printf("Usage:  %s <configFile>\n", os.Args[0])
		os.Exit(1)
	}

	fileName := os.Args[1]

	// initialize(fileName)
	go ipstack.Initialize(fileName)
	// myInterfaces := ipstack.GetInterfaces()
	// myNeighbors := ipstack.GetNeighbors()
	// myRoutes := ipstack.GetRoutes()

	go SendUpdates()
	

	scanner := bufio.NewScanner(os.Stdin)

	for scanner.Scan() {
		line := scanner.Text()
		switch line {
		case "li":
			fmt.Println("Name\tAddr/Prefix\tState")
			ipstack.SprintInterfaces()
		case "ln":
			fmt.Println("Iface\tVIP\tUDPAddr")
			ipstack.SprintNeighbors()
		case "lr":
			fmt.Println("T\tPrefix\tNext Hop\tCost")
			ipstack.SprintRoutingTable()
		case "q":
			ipstack.CleanUp()
			os.Exit(0)
		default:
			if len(line) > 4 {
				if line[:4] == "down" {
					// get interface name
					ifaceName := line[5:]
					ipstack.InterfaceDownREPL(ifaceName)
				}

				if line[:4] == "send" {
					// get IP address and message that follows it
					listOfWords := strings.Split(line, " ")
					ipAddr := listOfWords[1]
					message := listOfWords[2:]
					// combine message into one string
					messageToSend := strings.Join(message, " ")
					// convert message to byte array
					messageToSendBytes := []byte(messageToSend)
					// get interface by ipAddr
					iface, err := ipstack.GetNeighborByIP(ipAddr)
					if err != nil {
						fmt.Println(err)
						iface, err = ipstack.GetRouteByIP(ipAddr)
						if err != nil {
							fmt.Println(err)
							continue
						}
						ipstack.SendIP(ipstack.GetMyVIP(), iface, 0, messageToSendBytes, ipAddr)
					}
					ipstack.SendIP(ipstack.GetMyVIP(), iface, 0, messageToSendBytes, ipAddr)
				}
			}
			if len(line) > 2 {
				if line[:2] == "up" {
					// get interface name
					ifaceName := line[3:]
					ipstack.InterfaceUpREPL(ifaceName)
				}
			}
			continue
		}
	}
}