using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;

namespace NEA
{
    class Program
    {
        static void Main()
        {
            //Choose login or register

            Console.WriteLine("Please choose an option:\n1.Login\n2.Register");
            string choice = Console.ReadLine();

            switch(choice)
            {
                case "1":
                    Login();
                    break;
                case "2":
                    Register();
                    break;
            }
        }

        //Register method
        static void Register()
        {
            string usernameToFile = getUsername();
            string passwordToFile = getPassword();
            writeAccountToFile(usernameToFile,passwordToFile);

            //Local Function getUsername retrieves name, age and year group and forms the username
            string getUsername()
            {
                //Input name
                Console.Write("Enter name: ");
                string name = Console.ReadLine();

                //Input age
                Console.Write("Enter age: ");
                string age = Console.ReadLine();

                //Enter year group
                Console.Write("Enter year group: ");
                string yearGroup = Console.ReadLine();

                //Does the name contain less than 3 characters?
                string usernamePrefix;
                if (name.Length > 3)
                {
                    usernamePrefix = name.Substring(0, 3);
                }
                else
                {
                    usernamePrefix = name;
                }

                //Creating username
                string username = usernamePrefix + age;

                //Is the username a duplicate? CANNOT CREATE UNTIL ABLE TO WRITE TO FILE FOR FORMATTING REASONS
                int iterIfDupe = 0;
                bool isADupe = true;
                while (isADupe == true)
                {
                    string[] lines = File.ReadAllLines(@"C:\Users\maxto\Desktop\accounts.txt");
                    foreach (string line in lines)
                    {
                        if (username == line.Split(',')[0])
                        {
                            iterIfDupe++;
                            username = iterIfDupe + usernamePrefix + age;
                        }
                        else
                        {
                            isADupe = false;
                        }
                    }
                }

                return username;
            }

            //Local Function getPassword retrieves the password from the user and checks that it is longer than 7 chars
            string getPassword()
            {
                //Input password
                Console.Write("\nEnter your new password: ");
                string password = Console.ReadLine();

                //Does the password contain 8 or more characters?
                if(password.Length < 8)
                {
                    Console.WriteLine("Password must be at least 8 characters");
                    getPassword();
                }
                return password;
            }

            //Local Function writeAccount will write the username and password to a file
            void writeAccountToFile(string username,string password)
            {
                using (StreamWriter accountWriter = new StreamWriter(@"C:\Users\maxto\Desktop\accounts.txt",true))
                {
                    accountWriter.WriteLine($"{username},{password}");
                }
            }
            Main();
        }

        //Login method
        static void Login()
        {
            bool gotUsername = false;

            while (gotUsername == false)
            {
                //Getting username guess
                Console.Write("\nEnter username: ");
                string usernameGuess = Console.ReadLine();

                //Getting password guess
                Console.Write("Enter password: ");
                string passwordGuess = Console.ReadLine();

                //Checking if username is in account file
                string[] lines = File.ReadAllLines(@"C:\Users\maxto\Desktop\accounts.txt");
                foreach (string line in lines)
                {
                    if (usernameGuess == line.Split(',')[0] && passwordGuess == line.Split(',')[1])
                    {
                        Console.WriteLine("username correct");
                        gotUsername = true;
                        Globals.loggedIn = true;
                    }
                }
            }
            Main();
        }
    }
    public class Globals
    {
        public static bool loggedIn = false;
    }
}