using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1
{
    class Variables //Variables stored globally for all methods
    {
        public static decimal busDist = 0; //Distance the bus travelled
        public static decimal trainDist = 0; //Distance the train travelled
        public static decimal taxiDist = 0; //Distance the taxi travelled
        public static decimal busPass = 0; //Cost of the bus pass
        public static decimal trainTicket = 0; //Cost of the train ticket
        public static decimal taxiFare = 0; //Cost of the taxi fare
        public static decimal busCost = 0; //Cost of the bus per mile
        public static decimal trainCost = 0; //Cost of the train per mile
        public static decimal taxiCost = 0; //Cost of the taxi per mile
        public static decimal perCarDist = 0; //Distance travelled in personal car
        public static decimal perCarFuel = 0; //Cost of the personal car fuel
        public static decimal perCarCost = 0; //Cost of the personal car per mile

    }

    class Program //Contains all the methods used in the program
    {
        static void Main(string[] args) //Handover to Login
        {
            Login();
        }

        static void Login()
        {
            //Login
            string Username = "";
            string Password = "";
            string[] User = { "Jack", "Ryan", "Matty" };
            string[] Pass = { "123", "123", "123" };

            {
                Console.WriteLine("Username?");
                Username = Console.ReadLine();
                Console.WriteLine("Password?");
                Password = Console.ReadLine();
                //Detects if the user enters the correct Username and Password

                for (int i = 0; i < 3; i++)

                    if (Username == User[i] && Password == Pass[i])
                    {
                        Console.WriteLine("Success ");
                        Menu();
                    }
                Console.WriteLine("Unsuccessful attempt at login");
                Login();
            }
        } //Login

        static void Menu()
        {
            int x = 1;
            while (x == 1)
            {
                string choice;
                Console.WriteLine("Select an option: \n 1. Calculate cost per mile \n 2. Using personal car for business \n 3. Exit the program");
                choice = Console.ReadLine().ToLower();
                if (choice == "1")
                {
                    x = 0;
                    Distance();
                }
                if (choice == "2")
                {
                    Console.WriteLine("Success");
                    x = 0;
                    PerCar();
                }
                if (choice == "3")
                {
                    System.Environment.Exit(0);
                }
                else
                    Console.WriteLine("Please select an option");
            }
        } //Select whether to calculate distance or add usage for company car

        static void Distance()
        {
            //Asks the user what the distance travelled by each medium was

            Console.WriteLine("What is the distance travelled by bus in miles?");
            try
            {
                Variables.busDist = Convert.ToInt32(Console.ReadLine());
            }
            catch (SystemException)
            {
                Console.WriteLine("Error! Please write a number!");
                Distance();
            }

            Console.WriteLine("What is the distance travelled by train in miles?");

            try
            {
                Variables.trainDist = Convert.ToInt32(Console.ReadLine());
            }
            catch (SystemException)
            {
                Console.WriteLine("Error! Please write a number!");
                Distance();
            }

            Console.WriteLine("What is the distance travelled by taxi? in miles");
            try
            {
                Variables.taxiDist = Convert.ToInt32(Console.ReadLine());
            }
            catch (SystemException)
            {
                Console.WriteLine("Error! Please write a number!");
                Distance();
            }


            Price();
        } //Input distance per travel medium in miles

        static void Price()
        {
            //asks user what the cost of travel was

            Console.WriteLine("What is the cost of the bus pass in £?");

            try
            {
                Variables.busPass = Convert.ToInt32(Console.ReadLine()); //Tries to get the input from the user
            }
            catch (SystemException)
            {
                Console.WriteLine("Error! Please write a number!"); //Only runs if the input is in an incorrect format
                Price();
            }

            Console.WriteLine("What is the cost of the train ticket in £?");

            try
            {
                Variables.trainTicket = Convert.ToInt32(Console.ReadLine());
            }
            catch (SystemException)
            {
                Console.WriteLine("Error! Please write a number!");
                Price();
            }

            Console.WriteLine("What is the cost of the taxi fare in £?");

            try
            {
                Variables.taxiFare = Convert.ToInt32(Console.ReadLine());
            }
            catch (SystemException)
            {
                Console.WriteLine("Error! Please write a number!");
                Price();
            }


            TotalCost();

        }  //Input cost of pass/ticket/fare

        static void TotalCost()
        {
            //Works out the cost per mile was

            Variables.busCost = Math.Round(Variables.busPass / Variables.busDist, 2);
            Console.WriteLine("Bus costs £" + Variables.busCost + " per mile");

            Variables.trainCost = Math.Round(Variables.trainTicket / Variables.trainDist, 2);
            Console.WriteLine("train costs £" + Variables.trainCost + " per mile");

            Variables.taxiCost = Math.Round(Variables.taxiFare / Variables.taxiDist, 2);

            Console.WriteLine("taxi costs £" + Variables.taxiCost + " per mile");
            LeastExpensive();

        } //Calculates cost of each medium per mile

        static void LeastExpensive()
        {
            if (Variables.taxiCost == Variables.busCost && Variables.busCost == Variables.trainCost && Variables.trainCost == Variables.taxiCost)
            {
                Console.WriteLine("All mediums of travel cost the same");
            }

            else if (Variables.trainCost >= Variables.taxiCost && Variables.taxiCost > Variables.busCost)
            {

                Console.WriteLine("Bus is cheapest, costing £" + Variables.busCost + " per mile.");
            }

            else if (Variables.busCost >= Variables.taxiCost && Variables.taxiCost > Variables.trainCost)
            {
                Console.WriteLine("Train is cheapest, costing £" + Variables.trainCost + " per mile.");
            }

            else if (Variables.busCost >= Variables.trainCost && Variables.trainCost > Variables.taxiCost)
            {
                Console.WriteLine("Taxi is cheapest, costing £" + Variables.taxiCost + " per mile.");
            }

            else if (Variables.taxiCost == Variables.busCost)
                Console.WriteLine("Bus and taxi both cost £" + Variables.busCost + " per mile");

            else if (Variables.trainCost == Variables.busCost)
                Console.WriteLine("Bus and train both cost £" + Variables.busCost + " per mile");

            else if (Variables.taxiCost == Variables.trainCost)
                Console.WriteLine("Train and taxi both cost £" + Variables.taxiCost + " per mile");


            Console.ReadKey();
            System.Environment.Exit(0);
        } //Outputs most expensive medium

        static void PerCar()
        {
            Console.WriteLine("How far did you travel in miles?");
            try
            {
                Variables.perCarDist = Convert.ToInt32(Console.ReadLine());
            }
            catch (SystemException)
            {
                Console.WriteLine("Error! Please write a number!");
                PerCar();
            }

            Console.WriteLine("How much fuel did you pay for in £?");
            try
            {
                Variables.perCarFuel = Convert.ToInt32(Console.ReadLine());
            }
            catch (SystemException)
            {
                Console.WriteLine("Error! Please write a number!");
                PerCar();
            }


            Variables.perCarCost = Math.Round(Variables.perCarFuel / Variables.perCarDist, 3);
            Console.WriteLine("Personal car costs £" + Variables.perCarCost + " per mile \nYou have been paid 45p per mile, £" + (Convert.ToInt32(Variables.perCarDist) * 0.45));
            Console.ReadKey();
            System.Environment.Exit(0);

        } //calculates employee pay for miles
    }
}