package cmd

import (
	"bufio"
	"fmt"
	"log"
	"net"
	"strings"
)

var (
	listenPort string = "1302"
)

type Creator interface {
	CreateUser()
}

type User struct {
	Username string
	IP       string
}

func (u User) CreateUser(usr string, ip string) User {
	u.Username = usr
	u.IP = ip
	return u
}

func Server() {
	ln, err := net.Listen("tcp", ":"+listenPort)
	if err != nil {
		log.Fatalf("Error happened trying to listen on port: %v\n", err)
	}
	defer ln.Close()
	fmt.Printf("Listening on port %v...\n", listenPort)
	for {
		conn, err := ln.Accept()
		if err != nil {
			log.Fatalf("Error happened trying to accept connection: %v\n", err)
		}
		go handleConn(conn)
	}
}

func getUsername(conn net.Conn) (s string, err error) {
	conn.Write([]byte("What's your name?\nChoice: "))
	name, err := bufio.NewReader(conn).ReadString('\n')
	if err != nil {
		return "", err
	}
	trimmedName := strings.TrimRight(name, "\n")
	return trimmedName, nil
}

func getUserInput(conn net.Conn) (s string, err error) {
	message, err := bufio.NewReader(conn).ReadString('\n')
	if err != nil {
		return "", err
	}

	return message, nil
}

func handleConn(conn net.Conn) {
	defer conn.Close()

	//////////////////////////////////
	// Get user information
	//////////////////////////////////
	userName, err := getUsername(conn)
	if err != nil {
		log.Printf("Error occurred getting username: %v\n", err)
		return
	}
	userIP := getIP(conn)
	//////////////////////////////////

	newUserTemplate := new(User)
	newUser := newUserTemplate.CreateUser(userName, userIP)
	joinMessage := fmt.Sprintf("%v has joined the chat!", newUser.Username)
	fmt.Println(joinMessage)
	conn.Write([]byte(joinMessage))

	//////////////////////////////////
	for {
		message, err := getUserInput(conn)
		if err != nil {
			quitMessage := fmt.Sprintf("%v has disconnected!\n", newUser.Username)
			fmt.Print(quitMessage)
			if _, err := conn.Write([]byte(quitMessage)); err != nil {
				log.Printf("Error happened sending disconnect message: %v", err)
			}
			return
		}
		finalMessage := fmt.Sprintf("[%v] %v: %v", newUser.IP, newUser.Username, strings.TrimRight(message, "\n"))
		fmt.Printf("%v\n", finalMessage)
		if _, err := conn.Write([]byte(finalMessage)); err != nil {
			log.Printf("Error happened sending message: %v", err)
		}
	}
	//////////////////////////////////
}

func getIP(conn net.Conn) (IP string) {
	if addr, ok := conn.RemoteAddr().(*net.TCPAddr); ok {
		IP = fmt.Sprintf("%v", addr.IP)
	}
	return IP
}