using Ophelias.Expressions;
using Ophelias.Managers;
using Ophelias.Models;
using Ophelias.Reporting;
using System.Data.SQLite;

internal class Program
{
    private static string GetGuestEmail()
    {
        /*
         * This is a function that previously resided
         * within the GuestMode(), however this functionality
         * has been moved out as the AdminMode() relies on it
         * since this essentially is a email validation prompt.
         */
        Console.Write("Specify email: ");
        string Email = "";
        while (!Validation.ValidateEmail(Email))
        {
            Email = Console.ReadLine();
            if (!Validation.ValidateEmail(Email))
            {
                Console.Write("Please enter a valid email: ");
            }
        }
        return Email;
    }

    private static void GuestMode()
    {
        /*
         * Guest mode is meant for guests to create an account and make a reservation.
         * Specifically this mode allows for guests to create an account containing their
         * personal and payment information, create a reservation, manage that reservation, and/ or
         * pay for that reservation.
         */
        Reservation? activeReservation = null; // Holds the current reservation if one is loaded
        Guest? activeGuest = null; // Holds the active guest if one logs in
        void help()
        {
            /*
             * Used to inform users on what the commands do. See
             * the main while loop in GuestMode() for more details
             * on what these mean.
             */
            Console.WriteLine(
                "Reservation Commands:\n" +
                "\treservation create - Create a new reservation.\n" +
                "\treservation update - Update your active reservation.\n" +
                "\treservation cancel - Cancel a reservation.\n" +
                "\treservation pay - Pays in full for an active reservation.\n" +
                "Account Commands:\n" +
                "\taccount create - Create a new guest account.\n" +
                "\taccount update - Update your account information.\n" +
                "\taccount login - Log into your guest account." +
                "Enter Q or q to quit.\n"
            );
            return;
        }
        (string?, string?, string?) GetCreditCardInformation()
        {
            /*
             * This function attempts to gather creditcard information.
             * Since we need all three pieces, card number, expiration, and CCV
             * we provide options to quit for which the information is discarded
             * and null values are returned. If valid inputs are input and all
             * three pieces are collected, they are returned.
             */
            Console.Write("What is your credit card number: ");
            string CreditCard = "";
            while (!Validation.ValidateCreditCard(CreditCard))
            {
                CreditCard = Console.ReadLine().Trim().Replace("\t", "");
                if (CreditCard == "q" || CreditCard == "Q")
                {
                    return (null, null, null);
                }

                if (!Validation.ValidateCreditCard(CreditCard))
                {
                    Console.Write("Please enter a valid credit card. If your card is expired, enter Q to cancel: ");
                }
            }
            Console.Write("What is your credit card expiration date (MM/yy): ");
            string CardExpiration = "";
            while (!Validation.ValidateExpirationDate(CardExpiration))
            {
                CardExpiration = Console.ReadLine().Trim().Replace("\t", "");
                if (CardExpiration == "q" || CardExpiration == "Q")
                {
                    return (null, null, null);
                }

                if (!Validation.ValidateExpirationDate(CardExpiration))
                {
                    Console.Write("Please enter a valid expiration date. If your card is expired, enter Q to cancel: ");
                }
            }
            Console.Write("What is your credit card CCV: ");
            string CCV = "";
            while (!Validation.ValidateCCV(CCV))
            {
                CCV = Console.ReadLine().Trim().Replace("\t", "");
                if (CCV == "q" || CCV == "Q")
                {
                    return (null, null, null);
                }

                if (!Validation.ValidateCCV(CCV))
                {
                    Console.Write("Please enter a valid credit card CCV. If your card is expired, enter Q to cancel: ");
                }
            }
            return (CreditCard, CardExpiration, CCV);
        }
        (string, string) GetGuestName()
        {
            /*
             * This function is a series of while loops that will attempt
             * to collect a users first and last name, these are then returned
             * to the call location.
             */
            Console.Write("What is your first name: ");
            string FirstName = "";
            while (FirstName.Length == 0)
            {
                FirstName = Console.ReadLine();
                if (FirstName == "")
                {
                    Console.Write("What is your first name: ");
                }
            }
            Console.Write("What is your last name: ");
            string LastName = "";
            while (LastName.Length == 0)
            {
                LastName = Console.ReadLine();
                if (LastName == "")
                {
                    Console.Write("What is your last name: ");
                }
            }
            return (FirstName, LastName);
        }
        void GuestLogin()
        {
            /*
             * This function will attempt to login using an email specified by
             * the guest. We use email because they are designated as unique
             * identifiers and no two users can have the same email. For that reason
             * we use emails to login rather than collecting multiple pieces of
             * information or returning a list of accounts to scroll through.
             */
            Console.Write("\nEnter your email address: ");
            string email = "";
            while (!Validation.ValidateEmail(email))
            {
                /*
                 * This loop attepts to get a valid email. If there is no valid 
                 * formatted email it will keep trying.
                 */
                email = Console.ReadLine();
                if (!Validation.ValidateEmail(email))
                {
                    Console.Write("Please enter a valid email: ");
                }
            }
            activeGuest = Hotel.GetGuestByEmail(email);
            if (activeGuest == null)
            {
                Console.WriteLine($"\nNo account was found with the email {email}.");
                return;
            }
            Console.WriteLine($"\nYou have logged into {activeGuest.FirstName} {activeGuest.LastName} ({email}).");
            activeReservation = Hotel.GetResByGuest(activeGuest);
        }
        void CreateNewGuestPrompt()
        {
            /*
             * This prompt allows guest to create a new account using functionality that
             * has been split into other functions. See those functions for details on how
             * they work.
             */
            activeReservation = null;
            activeGuest = null;
            (string FirstName, string LastName) = GetGuestName();
            string Email = GetGuestEmail();
            activeGuest = Hotel.GetGuestByEmail(Email);
            if (activeGuest != null)
            {
                Console.WriteLine($"\nThere is already a guest with the email {Email}.");
                return;
            }
            Console.Write("Would you like to enter your credit card details? (Y/n): ");
            string? CreditCard = null;
            string? CardExpiration = null;
            string? CCV = null;
            while (true)
            {
                string input = Console.ReadLine();
                if (input.Equals("y") || input.Equals("Y"))
                {
                    (CreditCard, CardExpiration, CCV) = GetCreditCardInformation();
                    break;
                }
                else if (input.Equals("n") || input.Equals("N"))
                {
                    break;
                }
                else
                {
                    Console.Write("Input must be Y, y or N, n: ");
                }
            }

            activeGuest = new(FirstName, LastName, Email, CreditCard: CreditCard, Expiration: CardExpiration, CCV: CCV);
            Console.Write($"You are now logged in as {FirstName} {LastName} ({Email})");
        }
        void UpdateGuestInformation()
        {
            /*
             * This function allows a guest, if logged in, to update any piece of their
             * personal information. This includes name, email, and creditcard information.
             * For more information on how this gets set on the backend, see UpdateGuest()
             * in the Guest model.
             */
            if (activeGuest == null)
            {
                Console.WriteLine("No guest is currently logged in, please login.");
                return;
            }

            string? NewFname = null, NewLname = null, NewEmail = null, NewCard = null, NewExpiry = null, NewCCV = null;

            void SavePrompt()
            {
                /*
                 * This save prompt is just to inform users of their changes and show them
                 * what information gets updated. Also calls the UpdateGuest() function to
                 * update the database.
                 */
                if (NewFname == null && NewLname == null && NewEmail == null && NewCard == null && NewExpiry == null && NewCCV == null)
                {
                    Console.WriteLine("No changes have been made.");
                    return;
                }
                string changes = "";
                List<string> NewDetails = new();
                if (!string.IsNullOrEmpty(NewFname))
                {
                    NewDetails.Add($"\tFirst Name: {activeGuest.FirstName} -> {NewFname}");
                    activeGuest.FirstName = NewFname;
                }
                if (!string.IsNullOrEmpty(NewLname))
                {
                    NewDetails.Add($"\tLast Name: {activeGuest.LastName} -> {NewLname}");
                    activeGuest.LastName = NewLname;
                }
                if (!string.IsNullOrEmpty(NewEmail))
                {
                    NewDetails.Add($"\tEmail: {activeGuest.Email} -> {NewEmail}");
                    activeGuest.Email = NewEmail;
                }
                if (!string.IsNullOrEmpty(NewCard))
                {
                    NewDetails.Add($"\tCredit Card: {activeGuest.CreditCard} -> {NewCard}");
                    activeGuest.CreditCard = NewCard;
                }
                if (!string.IsNullOrEmpty(NewExpiry))
                {
                    NewDetails.Add($"\tCard Expiration Date: {activeGuest.Expiration} -> {NewExpiry}");
                    activeGuest.Expiration = NewExpiry;
                }
                if (!string.IsNullOrEmpty(NewCCV))
                {
                    NewDetails.Add($"\tCard CCV: {activeGuest.CCV} -> {NewCCV}");
                    activeGuest.CCV = NewCCV;
                }
                if (NewDetails.Count > 0)
                {
                    changes += string.Join("\n", NewDetails);
                }

                Console.WriteLine($"The following changes have been made:\n {changes}");
                activeGuest.UpdateGuest(activeGuest.Id, NewFname, NewLname, NewEmail, NewCard, NewExpiry, NewCCV);
                activeReservation.Guest = activeGuest;
                return;
            }

            Console.WriteLine($"You are currently logged in as {activeGuest.FirstName} {activeGuest.LastName} ({activeGuest.Email}).\n" +
                $"If this is not your account, please (Q)uit and log into your account. Changes will be recorded, but not saved\n" +
                $"until you enter S.\n");

            do
            {
                /*
                 * This loop traps users until the enter one of the cases which results
                 * in updating a piece of information, saving their changes, or discarding
                 * them.
                 */
                Console.Write("Please select the option you would like to change or enter S to save:\n" +
                    "1. First Name and Last Name\n" +
                    "2. Email Address\n" +
                    "3. Credit Card Information\n");
                switch (Console.ReadLine())
                {
                    case "q": return;
                    case "Q": return;
                    case "1": (NewFname, NewLname) = GetGuestName(); break;
                    case "2": NewEmail = GetGuestEmail(); break;
                    case "3": (NewCard, NewExpiry, NewCCV) = GetCreditCardInformation(); break;
                    case "S": SavePrompt(); return;
                    default: break;
                }
            } while (true);
        }
        ReservationType SelectReservation()
        {
            /*
             * This function was broken out to allow it to be reused in multiple sections.
             * It prompts a user for their selection of reservation type and that type
             * is then returned. We subtract 1 from the type since we start our input
             * options at 1 instead of 0 (Enums start at 0).
             */
            string input = "";
            Console.Write("What kind of reservation would you like to make?\n" +
                "1. Conventional\n" +
                "2. Prepaid\n" +
                "3. 60 Day Advance\n" +
                "4. Incentive\n" +
                "Input a number: ");
            while (true)
            {
                input = Console.ReadLine();
                if (input == "1" || input == "2" || input == "3" || input == "4")
                {
                    break;
                }

                Console.Write("Please enter either 1, 2, 3, or 4: ");
            }
            return (ReservationType)(Convert.ToInt32(input) - 1);
        }
        bool CheckReservationRestrictions(DateTime Date, ReservationType Type)
        {
            /*
             * This function checks to see if there are reservation restrictions.
             * Prepaid reservations must be made 90 days ahead of the start date
             * and 60-day 60 days. This function informs the user if their reservation
             * does not adhere to these constraints.
             */
            if (Type == ReservationType.Prepaid)
            {
                if ((int)(Date - DateTime.Now).TotalDays < 90)
                {
                    Console.WriteLine("Prepaid reservations must be made 90 days in advance.");
                    return false;
                }
                else
                {
                    return true;
                }
            }
            else if (Type == ReservationType.SixtyDayAdvance)
            {
                if ((int)(Date - DateTime.Now).TotalDays < 60)
                {
                    Console.WriteLine("Sixty-days-in-advance reservations must be made 60 days in advance.");
                    return false;
                }
                else
                {
                    return true;
                }
            }
            return true;
        }
        (DateTime?, DateTime?) SelectDate(ReservationType Type)
        {

            (DateTime, DateTime) Dates()
            {
                string input = "";
                DateTime _StartDate;
                DateTime _EndDate;
                Console.Write("When would you like to begin your stay.\n" +
                    "Your date input should be in in the following format - yyyy-MM-dd. Example: (2021-12-31)?\n" +
                    "Input a date (2021-12-31): ");
                while (true)
                {
                    input = Console.ReadLine();
                    if (DateTime.TryParse(input, out _StartDate) && _StartDate >= DateTime.Now)
                    {
                        break;
                    }

                    if (_StartDate <= DateTime.Now)
                    {
                        Console.Write("Start date cannot be before current date. Please enter a valid date (2021-12-31): ");
                    }
                    else
                    {
                        Console.Write("Please enter a valid date (2021-12-31): ");
                    }
                }
                Console.Write("When would you like to end your stay.\n" +
                   "Your date input should be in in the following format - yyyy-MM-dd. Example: (2021-12-31)?\n" +
                   "Input a date (2021-12-31): ");
                while (true)
                {
                    input = Console.ReadLine();
                    if (DateTime.TryParse(input, out _EndDate) && _EndDate > _StartDate)
                    {
                        break;
                    }

                    if (_EndDate < _StartDate)
                    {
                        Console.Write("End date must be after start date. Please enter a valid date (2021-12-31): ");
                    }
                    else
                    {
                        Console.Write("Please enter a valid date (2021-12-31): ");
                    }
                }
                return (_StartDate.Date, _EndDate.Date);
            }

            DateTime StartDate;
            DateTime EndDate;
            string input;

            while (true)
            {
                bool maxCapacity = false;
                (StartDate, EndDate) = Dates();
                if (StartDate == null || EndDate == null)
                {
                    (_, maxCapacity) = Hotel.AvgOccupancySpan(StartDate, EndDate);
                }

                if (!maxCapacity)
                {
                    if (!CheckReservationRestrictions(StartDate, Type))
                    {
                        Console.Write("Do you want to quit? Type YES to quit and discard, enter anything or nothing to select another date range.\n" +
                                       ": ");
                        input = Console.ReadLine();
                        if (input == "YES")
                        {
                            Console.WriteLine("Aborting reservation changes.");
                            return (null, null);
                        }
                    }
                    else
                    {
                        break;
                    }
                }
                else
                {
                    Console.WriteLine("Your reservation covers a range where we are already at max capacity, please change your reservation dates.");
                }

            }
            return (StartDate, EndDate);

        }
        void CreateNewReservation()
        {
            /*
             * Allows users with no existing reservation to make a new reservation.
             * If a user is not logged in, they will not be able to register either.
             * The reservation will collect all the necessary information depending
             * on requirements set by the reservation. Specifically if the reservation
             * is anything but 60-day-in-advance, the creditcard is required. If users
             * do not want to proceed, the are free to cancel and abort the creation
             * of their reservation.
             */
            if (activeGuest == null)
            {
                Console.WriteLine("No guest is currently logged in, please login.");
                return;
            }
            if (activeReservation != null)
            {
                Console.WriteLine("You currently have an active registration.");
                return;
            }
            if (Hotel.GetBaseRate() == null)
            {
                Console.WriteLine("Unable to proceed with reservation due to no base rate being set. Please inform an employee.");
                return;
            }

            string input;

            ReservationType Type;
            DateTime? StartDate;
            DateTime? EndDate;

            Type = SelectReservation();
            (StartDate, EndDate) = SelectDate(Type);
            if (StartDate == null || EndDate == null)
            {
                Console.WriteLine("Aborting reservation creation.");
                return;
            }
            string? cc, exp, ccv;
            while ((Type != ReservationType.SixtyDayAdvance &&
                (activeGuest.CreditCard == null || activeGuest.Expiration == null || activeGuest.CCV == null)))
            {
                Console.Write("The reservation type you chose requires you to specify your credit card.\n" +
                    "If you are unable to provide one, enter Q to quit or hit enter to continue.\n" +
                    ": ");
                input = Console.ReadLine();
                if (input == "Q")
                {
                    return;
                }
                (cc,exp,ccv) = GetCreditCardInformation();
                if (cc != null && exp != null && ccv != null) 
                    activeGuest.UpdateGuest(activeGuest.Id, CreditCard: cc, Expiration: exp, CCV: ccv);
            }

            Console.Write($"Thank you for filling out your reservation details. Currently you have made a {Type} " +
                $"reservation and are scheduled to stay from {StartDate.Value.ToString("yyyy-MM-dd")} to {EndDate.Value.ToString("yyyy-MM-dd")}." +
                $"If these details are correct, enter YES to complete. To cancel your reservation enter Q.\n" +
                $": ");
            input = Console.ReadLine();
            while (input != "YES")
            {
                if (input == "Q")
                {
                    Console.WriteLine("Reservation has been deleted.");
                    return;
                }
                else
                {
                    Console.Write("Input must be YES or Q.\n: ");
                    input = Console.ReadLine();
                }
            }
            if (Type == ReservationType.Prepaid) // Creates a new reservation and set it as the active. Also pays for the reservation if the reservation type was prepaid.
            {
                activeReservation = new(activeGuest, Type, DateTime.Now.Date, StartDate.Value, EndDate.Value);
                activeReservation.Transaction.Pay(activeReservation.Transaction.Owed, activeGuest.CreditCard);
            }
            else // Creates a new reservation and set it as the active.
            {
                activeReservation = new(activeGuest, Type, DateTime.Now.Date, StartDate.Value, EndDate.Value);
            }
            Console.WriteLine("Your reservation has been made.");
        }
        void UpdateReservation()
        {
            /*
             * Update reservation allows guests to change their reservation at the
             * cost of having to pay a new amount based on the current base rate 
             * with a multiplier of 110% or 1.1. If a user opts to not update
             * their reservation the changes will be discarded. Furthermore the
             * system prevents people from registering when the hotel is at max
             * capacity for a certain date. For more details, see the SelectDate()
             * function. If a user is not logged in, they will not be able to update
             * their reservation.
             */
            string input = "NO";
            if (activeGuest == null)
            {
                Console.WriteLine("No guest is currently logged in, please login.");
                return;
            }
            if (activeReservation == null)
            {
                Console.WriteLine("You currently do not have an active registration.");
                return;
            }

            Console.Write("Your current reservation details are:\n" +
                $"\tStarts on: {activeReservation.StartDate.ToString("yyyy-MM-dd")}\n" +
                $"\tEnds on: {activeReservation.EndDate.ToString("yyyy-MM-dd")}\n");
            DateTime? _StartDate = null, _EndDate = null;
            do
            {
                if (input == "NO")
                {
                    (_StartDate, _EndDate) = SelectDate(activeReservation.Type);
                    if (_StartDate.HasValue && _EndDate.HasValue)
                    {
                        Console.Write("Your new reservation details are:\n" +
                            $"\tStarts on: {activeReservation.StartDate.ToString("yyyy-MM-dd")} -> {_StartDate.Value.ToString("yyyy-MM-dd")}\n" +
                            $"\tEnds on: {activeReservation.EndDate.ToString("yyyy-MM-dd")} -> {_EndDate.Value.ToString("yyyy-MM-dd")}\n");
                    }

                    Console.Write("Are you done with your changes?\n" +
                        "Enter YES to finish and save, NO to continue editing.\n" +
                        ": ");
                }
                else if (input == "Q")
                {
                    Console.WriteLine("Your changes have been discarded.");
                    return;
                }
                else
                {
                    Console.WriteLine("Input must be YES, NO, or Q.");
                    Console.Write(": ");
                }
                input = Console.ReadLine();
            } while (input != "YES");
            if (_StartDate != null && _EndDate != null)
            {
                activeReservation.ChangeReservationDates((DateTime)_StartDate, (DateTime)_EndDate);
                Console.WriteLine("Your changes have been saved.");
            }
            return;
        }
        void CancelReservation()
        {
            /*
             * This function will provide guests with the option to cancel their reservation
             * or abort if they decide they do not want to cancel. If the reservation is cancelled,
             * the reservation cancellation function CancelReservation() is called on the reservation
             * and the database is updated accordingly. See CancelReservation() for more details.
             * If a user is not logged in, they will not be able to cancel either.
             */
            if (activeGuest == null)
            {
                Console.WriteLine("No guest is currently logged in, please login.");
                return;
            }
            if (activeReservation == null)
            {
                Console.WriteLine("You currently do not have an active registration.");
                return;
            }
            string input;
            Console.Write("Would you like to cancel your reservation?\n" +
                "You may be charged depending on your reservation.\n" +
                "Enter YES to confirm or NO to exit: ");
            input = Console.ReadLine();
            while (input != "YES")
            {
                if (input == "NO")
                {
                    Console.Write("Reservation has not been cancelled.");
                    return;
                }
                else
                {
                    Console.Write("Your input must be YES or NO: ");
                    Console.ReadLine();
                }
            }
            activeReservation.CancelReservation();
            activeReservation = null;
            Console.Write("Reservation has been cancelled, you may be charged based on your reservation.");
        }
        void PayForReservation()
        {
            /*
             * This function allows for guests to pay for their 60-day-in-advance if they
             * meet the 30-45 day before start date window. All other reservations are denied
             * the ability to pay since they have specific points at which they are charged.
             * If there is no creditcard information, this function will attempt to collect it
             * and then update the guests information before paying for the transaction. Depending
             * on various factors, the transaction may be completed or invalid. However
             * since the current design is to have members pay in full, most of these cases
             * should be impossible to trigger. Currently they are implemented for future changes
             * or if they do trigger.
             */
            if (activeGuest == null)
            {
                Console.WriteLine("No guest is currently logged in, please login.");
                return;
            }
            if (activeReservation == null)
            {
                Console.WriteLine("You currently do not have an active registration.");
                return;
            }

            if (ReservationType.Incentive == activeReservation.Type)
            {
                Console.WriteLine("Incentive reservations are paid for when you check-out.");
                return;
            }
            else if (ReservationType.Conventional == activeReservation.Type)
            {
                Console.WriteLine("Conventional reservations are paid for when you check-out.");
                return;
            }
            else if (ReservationType.Prepaid == activeReservation.Type)
            {
                Console.WriteLine("Prepaid reservations are paid for when you create them.");
                return;
            } else if (ReservationType.SixtyDayAdvance == activeReservation.Type)
            {
                /*
                 * Checks to see if the reservation has been paid for are is past the latest possible
                 * payment date. If it has been payed, the user will be informed, if it is past the
                 * payment collection date, the reservation is cancelled and user is notified.
                 */
                if(activeReservation.StartDate.AddDays(-30).Date < DateTime.Now.Date)
                {
                    if (activeReservation.Transaction.Owed <= activeReservation.Transaction.AmountPaid)
                    {
                        Console.WriteLine("Your reservation has already been paid for.");
                        return;
                    }
                    activeReservation.CancelReservation();
                    Console.WriteLine("Your reservation has been cancelled because you failed to pay within the payment period.");
                    return;
                }
            }

            string? cc, exp, ccv;
            cc = activeGuest.CreditCard;
            exp = activeGuest.Expiration;
            ccv = activeGuest.CCV;
            while (true)
            {
                /*
                 * This loop traps the user until they either choose to pay or not.
                 * If the card details they specify are invalid at any point within the latest
                 * date of the payment, we choose to reject that as it theoretically could cause
                 * problems. In this hypothetical situation is would not but in the real world it
                 * might depending on the card vendor. If a user choses to abort payment, the function
                 * will discard any changes to that guests payment information if changes were made.
                 * In the case where a customers payment information is already valid, they will pay for
                 * the reservation in full without any prompts.
                 */

                if (cc == null || exp == null || ccv == null) // Trigger to get new card information
                {
                    Console.Write("Would you like to try again and enter your payment information? (Your reservation will not be canceled)\n" +
                        "YES or NO: ");
                    while (true)
                    {
                        string input = Console.ReadLine();
                        if (input == "YES")
                        {
                            break;
                        } else if (input == "NO")
                        {
                            Console.WriteLine("Payment has been aborted.");
                            return;
                        }
                        else
                        {
                            Console.WriteLine("Input must be YES or NO.");
                        }
                    }
                    (cc, exp, ccv) = GetCreditCardInformation(); // See for more information on how input is collected.

                } else if (cc != null && exp != null && ccv != null)
                {
                    /*
                     * If the creditcard is not null, this section checks to see if payment can be made.
                     * If payment can be made the guest information is updated and an attempt to pay is made.
                     * The payment can result in any of the following:
                     *    
                     *      Successful
                     *          Payment was made and recorded
                     *          
                     *      Failed
                     *          An error occurred and the staff should be notified
                     *          
                     *      Attempt to pay $0 or less
                     *          Self explanatory
                     *      
                     *      Missing card information
                     *          If the card is missing payments cannot be made
                     *          
                     *      Already Paid
                     *          The payment has already been paid at an earlier date
                     *          or due to some other factor, therefore there was no need to charge.
                     */
                    if (ReservationType.SixtyDayAdvance == activeReservation.Type && ((DateTime.Parse(exp).Date < activeReservation.StartDate.AddDays(-30).Date) && (DateTime.Parse(exp).Date < activeReservation.StartDate.AddDays(-45).Date)))
                    {
                        Console.WriteLine("Your card expires too soon. Please enter the correct expiration date if incorrect or a new card.");
                        cc = null;
                        exp = null;
                        ccv = null;
                    }
                    else if (ReservationType.SixtyDayAdvance == activeReservation.Type && ((DateTime.Parse(exp).Date > activeReservation.StartDate.AddDays(-30).Date) && (DateTime.Parse(exp).Date > activeReservation.StartDate.AddDays(-45).Date)))
                    {
                        if (cc != activeGuest.CreditCard && exp != activeGuest.Expiration && ccv != activeGuest.CCV)
                        {
                            activeGuest.UpdateGuest(activeGuest.Id, CreditCard: cc, Expiration: exp, CCV: ccv);
                            activeReservation.Guest = activeGuest;
                        }
                        PaymentStatus ps = activeReservation.Transaction.Pay(activeReservation.Transaction.Owed, activeGuest.CreditCard);
                        if (ps == PaymentStatus.SuccessfulPayment)
                        {
                            Console.WriteLine("Your reservation has been paid for.");
                            return;
                        } else if (ps == PaymentStatus.FailedPayment)
                        {
                            Console.WriteLine("There was an error paying for your resevation. Try again later or contact the Ophelias Oasis team.");
                            return;
                        } else if (ps == PaymentStatus.AmountCannotZero)
                        {
                            Console.WriteLine("You cannot pay $0 or less than $0.");
                            return;
                        } else if (ps == PaymentStatus.MissingCreditCard)
                        {
                            Console.WriteLine("Credit Card information is missing. Payment could not be made.");
                        } else if (ps == PaymentStatus.AlreadyPaid)
                        {
                            Console.WriteLine("Your reservation has already been paid for.");
                            return;
                        }
                    }
                }
            }
        }
        Console.Write(
                "\nWelcome to the Ophelias Oasis Hotel Registration System!\n" +
                "Type help to get a full list of commands or enter a command.\n" +
                "Command: "
        );
        while (true)
        {
            /*
             * This is the main administrator loop.
             * The following are valid operations:
             *      
             *      reservation create:
             *          Creates a new reservation with the information specified by the guest.
             *          For more information see the CreateNewReservation() function.
             *          
             *      reservation update:
             *          Updates an existing reservation if there is one. If there is no existing
             *          reservation the function will immediately return. To get more information
             *          see the UpdateReservation() function.
             *          
             *      reservation cancel:
             *          Cancels a reservation. If the reservation is subject to penalties, the
             *          guest will be charged. For more infromation, see CancelReservation().
             *          
             *      reservation pay:
             *          Enables 60-day-in-advance reservees to pay for their reservations if
             *          they are within the valid payment window. Other reservation types will
             *          be blocked. For more details, see PayForReservation().
             *          
             *      account create:
             *          Enables guests to create a new account. See CreateNewGuestPrompt for
             *          more details on account creation.
             *          
             *      account update:
             *          Update an existing guests information, such as name, email, and
             *          creditcard information. For more details on how this is handled,
             *          see UpdateGuestInformation().
             *          
             *      account login:
             *          Logs into an account using a guests email if they have an account.
             *          For more details see GuestLogin().
             *          
             *      Q and q:
             *          Returns to the main loop for choosing either the Guest or Admin flow.
             */
            Hotel.CheckBaseRate();
            string? input = Console.ReadLine();
            switch (input)
            {
                case "help": help(); break; // Gets help text
                case "reservation create": CreateNewReservation(); break; // Allows guests to create a reservation
                case "reservation update": UpdateReservation(); break; // Allows guests to update a reservation if they have one
                case "reservation cancel": CancelReservation(); break; // Allows guests to cancel a reservation if they have one
                case "reservation pay": PayForReservation(); break; // Allows guests with 60-day reservations to pay for it
                case "account create": CreateNewGuestPrompt(); break; // Creates a new guest
                case "account update": UpdateGuestInformation(); break; // Updates a guests personal and/ or payment information
                case "account login": GuestLogin(); break; // Logs a guest in
                case "q": return; // Quit to mode loop
                case "Q": return; // Quit to mode loop
                default: Console.WriteLine("Unknown command, enter help for more inforamtion."); break;
            }
            Console.Write("\nCommand: ");
        }
    }
    private static void AdminMode()
    {
        /*
         * Admin mode is meant for employees. There is no authetication or security measures
         * for this class as the design specification did not include that and for the goals
         * of this project, security was not to be a concern. Realistically this would be
         * handled differently and securely.
         * 
         * The pupose of this class is to provide employees with the ability to perform
         * specific operations such as checking/ checking out a guest, generating
         * reports that management needs to understand how the hotel is operating,
         * a system to set the hotels rates, and the ability to issue penalties and/ or
         * notify outstanding payments. For more details on how each of these components work,
         * see the documentation within their functions.
         */
        void help()
        {
            /*
             * Help text to understand commands.
             */
            Console.WriteLine(
                "Report Commands:\n" +
                "\tgenerate management report - Generates a daily management report on expected occupancy, room income, and incentive losses.\n" +
                "\tgenerate operational report - Generates a report of daily arrivals and occupancy.\n" +
                "\tgenerate accommodation bills - Generates an accommodation bill that will be handed to guests upon checkout.\n" +
                "\nManagement Commands:\n" +
                "\tnotify pending payments - Generates and emails 60 day advance reservations that they must pay for their reservation or it will be cancelled.\n" +
                "\tissue penalties - Issues penalties for guests that are no shows.\n" +
                "\tcheckin guest - Checks in a guest and assigns them a room.\n" +
                "\tcheckout guest - Checks out a guest and removes their room assignment.\n" +
                "\tset rate - Sets a new base rate to begin after a specified date.\n" +
                "\nEnter Q or q to quit.\n"
            );
            return;
        }
        void SetFutureBaseRate()
        {
            /*
             * Allows employees to configure a future base rate. See SetRatePrompt() for the
             * details as it was broken out into a nested function.
             */
            bool SetRatePrompt(DateTime? FixedDate = null)
            {
                /*
                 * This function promopts an employee with a base rate configuration prompt.
                 * If this is the first time configuring the base rate, in cases where one is not set,
                 * the default rate will be set effective immediately, otherwise the base rate prompt
                 * will require the employee to set the base rate sometime in the future. The accepted inputs
                 * are checked against the function ValidateMoney() which basically checks for how money is typically
                 * represented in the United States.
                 */
                string input;
                string amount;
                amount = Console.ReadLine();
                if (Validation.ValidateMoney(amount))
                {
                    Console.Write($"Is this the correct base rate {amount}?\n" +
                        $"Enter YES or NO: ");
                    input = Console.ReadLine();
                    while (input != "YES")
                    {
                        if (input == "NO")
                        {
                            break;
                        }
                        else
                        {
                            Console.Write("Input must be YES or NO: ");
                        }
                        input = Console.ReadLine();
                    }
                    if (input == "YES")
                    {
                        if (FixedDate != null)
                        {
                            if (Hotel.GetBaseRateByDate((DateTime)FixedDate))
                            {
                                Console.Write("There is already a base rate configured for this date.\n" +
                                    "If you are entering a new rate because one was not configured and got this error, type YES.\n" +
                                    "Would you like to overwrite it (YES)? If not enter anything to continue.\n" +
                                    ": ");
                                if (Console.ReadLine() == "YES")
                                {
                                    Hotel.UpdateBaseRate(Convert.ToDouble(amount), FixedDate.Value.Date, DefaultRate: true); // Replaces the existing base rate with a new value if the date matches. Also marks as default.
                                    return true;
                                }
                            }
                            else
                            {
                                Hotel.SetBaseRate(Convert.ToDouble(amount), (DateTime)FixedDate, true); // Sets the base rate as the default.
                            }

                            Console.WriteLine($"A base rate of {amount} has been set and will take effect immediately.");
                        }
                        else
                        {
                            DateTime StartDate;
                            Console.Write("When would you like the new rate to take effect.\n" +
                                "Your date input should be in in the following format - yyyy-MM-dd. Example: (2021-12-31)?\n" +
                                "Input a date (2021-12-31): ");
                            while (true)
                            {
                                input = Console.ReadLine();
                                if (DateTime.TryParse(input, out StartDate))
                                {
                                    if (StartDate.Date <= DateTime.Now.Date)
                                    {
                                        Console.WriteLine("Base rate must be configured for a future night. Not the same day or past.");
                                    }
                                    else if (Hotel.GetBaseRateByDate(StartDate))
                                    {
                                        Console.Write("There is already a base rate configured for this date.\n" +
                                            "Would you like to overwrite it (YES)? If not enter anything to continue." +
                                            ": ");
                                        if (Console.ReadLine() == "YES")
                                        {
                                            Hotel.UpdateBaseRate(Convert.ToDouble(amount), StartDate.Date); // Replaces the existing base rate with a new value if the date matches.
                                            return true;
                                        }
                                    }
                                    else
                                    {
                                        break;
                                    }
                                }

                                Console.Write("Please enter a valid date (2021-12-31): ");
                            }
                            Hotel.SetBaseRate(Convert.ToDouble(amount), StartDate); // Sets the base rate as a future base rate.
                            Console.WriteLine($"A base rate of {amount} has been set and will take effect on {DateTime.Now.Date.ToString("yyyy-MM-dd")}.");
                        }
                        return true;
                    }
                }
                else
                {
                    Console.WriteLine("Your input was not a valid input, an example of a valid input would be 100 or 100.00.");
                }
                Console.Write("Enter new rate: ");
                return false;
            }

            if (Hotel.GetBaseRate() == null)
            {
                // This is for the specific case where there is no configured/ default rate.
                Console.Write("No base rate has been configured. " +
                    "You must set one for the current date.\n" +
                    "Enter new rate: ");
                while (!SetRatePrompt(DateTime.Now.Date)) { } // Continues to loop until a base rate is successfully configured.
            }
            else
            {
                Console.Write("What is the value of the rate you would like to set.\n" +
                   "Enter new rate: ");
                while (!SetRatePrompt()) { } // Continues to loop until a base rate is successfully configured.
            }
        }
        void CheckIn()
        {
            /*
             * Checks in a guest if they have an existing reservation that can be checked in.
             * If not the function informs the employee that no reservation exists or no guest
             * guest account could be found. This function will also assign the guest their room
             * number or cancel their reservation if they attempt to check in after their start date
             * as the policy calls for "no-shows" to be charged and therefore are canceled due to a
             * no refund policy. Guests also cannot check in ahead of time, only on the day of.
             */
            string Email = GetGuestEmail();
            TimeRefs? status = Hotel.CanBeCheckedIn(Email);
            Guest? g = Hotel.GetGuestByEmail(Email);
            if (g == null)
            {
                Console.WriteLine("No guest with that email exists.");
                return;
            }
            if (!status.HasValue)
            {
                Console.WriteLine("No reservation exists for this email.");
                return;
            }

            if (status.Value == TimeRefs.OnTime)
            {
                int? RoomID = Hotel.CheckInGuest(Email, DateTime.Now.Date);
                if (RoomID != null)
                {
                    Console.WriteLine($"Guest has been checked in, their room number is {RoomID}.");
                }
            }
            else if (status.Value == TimeRefs.Late)
            {
                Console.WriteLine("Since the reservation was not checked in on the date scheduled, it has been cancelled. The guest will be charged the \"no show\" penalty.");
                Reservation? r = Hotel.GetResByGuest(g);

                if (r == null)
                {
                    throw new Exception();
                }

                r.CancelReservation();

            }
            else if (status.Value == TimeRefs.Early)
            {
                Console.WriteLine("Since the reservation was not checked in on the date scheduled, it has been cancelled. The guest will be charged the \"no show\" penalty.");
            }
            return;
        }
        void CheckOut()
        {
            /*
             * Checks out a guest and charges them if they have an incentive or conventional reservation.
             * For more details on how the data is manipulated, see Pay() and CheckOutGuest(). While
             * there are null refs warnings here, they should never reach this point
             * so we choose not to handle them.
             */
            string Email = GetGuestEmail();
            if (Hotel.GuestCurrentlyCheckedIn(Email))
            {
                Reservation r = Hotel.GetResByGuest(Hotel.GetGuestByEmail(Email));
                if (r.Type == ReservationType.Incentive || r.Type == ReservationType.Conventional)
                {
                    r.Transaction.Pay(r.Transaction.Owed, r.Guest.CreditCard);
                }

                Hotel.CheckOutGuest(Email, DateTime.Now.Date);
                Console.WriteLine($"Guest has been checked out.");
            }
            else
            {
                Console.WriteLine($"Can't checkout a guest that hasn't been checked in.");
            }
            return;
        }
        void NotifyOutstandingPayments()
        {
            /*
             * This function is used to notify any 60-day-in-advance reservation that they have a payment
             * due. If the payment is past the number of days then the reservation is canceled. If the
             * reservation is within the 30-45 day window then an email is sent out for a customer to
             * pay through the payment system. For more details on how the email works, see the Email class.
             */
            List<Reservation> activeSixtyRes = Hotel.GetActiveSixtyDayRes();
            foreach (Reservation r in activeSixtyRes)
            {
                int days = (int)(r.StartDate.Date - DateTime.Now.Date).TotalDays - 30;
                if (days < 0)
                {
                    r.CancelReservation();
                }
                else if (days <= 15)
                {
                    Email e = new(r.Guest.Email);
                    e.Send();
                }
            }
            if (File.Exists("Emails.txt") && activeSixtyRes.Count != 0)
            {
                FileInfo f = new("Emails.txt");
                Console.WriteLine($"Emails have been written and appended to {f.FullName}");
            } else
            {
                Console.WriteLine("There are no emails to send.");
            }
        }
        void GenerateManagementReports()
        {
            /*
             * GenerateManagementReports is used to generate the following reports:
             * 
             *      - Expected Occupancy
             *          Reports the expected hotel occupancy and relies on GetExpectedOccupancyCount()
             *          for the data used in reporting. See CalculateExpectedOccupancy() for more details
             *          on the output.
             *          
             *      - Expected Income
             *          Reports the expected income for the hotel and relies on GetExpectedIncomeCount()
             *          for the data used in reporting. See CalculateExpectedIncome() for more details
             *          on the output.
             *          
             *      - Incentive Losses
             *          Reports the revenue lost as a result of providing incentives and relies on
             *          GetIncentiveTransactions() for the data used in reporting. See CalculateIncentiveLosses()
             *          for more details on the output.
             */
            var w = Hotel.GetExpectedOccupancyCount();
            Management.CalculateExpectedOccupancy(w.Item2, w.Item1);
            if (File.Exists("ExpectedOccupancy.txt"))
            {
                FileInfo f = new("ExpectedOccupancy.txt");
                Console.WriteLine($"Expected occupancy has been written and appended to {f.FullName}");
            }
            var x = Hotel.GetExpectedIncomeCount();
            Management.CalculateExpectedIncome(x.Item1, x.Item2, x.Item3);
            if (File.Exists("ExpectedIncome.txt"))
            {
                FileInfo f = new("ExpectedIncome.txt");
                Console.WriteLine($"Expected income has been written and appended to {f.FullName}");
            }
            var y = Hotel.GetIncentiveTransactions();
            Management.CalculateIncentiveLosses(y.Item3, y.Item1, y.Item2);
            if (File.Exists("IncentiveLosses.txt"))
            {
                FileInfo f = new("IncentiveLosses.txt");
                Console.WriteLine($"Incentive losses have been written and appended to {f.FullName}");
            }
        }
        void GenerateAccommodationBills()
        {
            /*
             * This generates a single report called accommodation bills. If there
             * are no reservations there will be no accomodation bills to generate.
             * The reservations are returned by GetDailyArrivals().
             */
            List<Reservation> reservations = Hotel.GetDailyArrivals();

            if (reservations.Count == 0)
            {
                Console.WriteLine($"No accommodation bills to generate.");
                return;
            }

            Accommodation.GenerateAccommodationBills(reservations);

            if (File.Exists("AccommodationBills.txt"))
            {
                FileInfo f = new("AccommodationBills.txt");
                Console.WriteLine($"Accommodation bills have been written and appended to {f.FullName}");
            }
        }
        void GenerateOperationalReports()
        {
            /*
             * This generates two operational reports. The daily arrivals and the daily occupancy.
             * The daily arrival report is generated based off list of reservations returned by
             * GetDailyArrivals(). This is then passed off to the Operational reporting class
             * where it writes out to DailyArrivals.txt. THe same applies to the daily occupancy
             * however the GetDailyOccupancy() function is a litte more complex returning two lists,
             * one with the occupancy for that day and one with rooms occupied the night before.
             * If the file(s) are successfully written, the output is printed to the console for
             * staff to find them.
             */
            List<Reservation> reservations = Hotel.GetDailyArrivals();

            if (reservations.Count == 0)
            {
                Console.WriteLine($"No daily arrivals to report.");
            } else
            {
                Operational.FetchDailyArriavals(reservations);
                if (File.Exists("DailyArrivals.txt"))
                {
                    FileInfo f = new("DailyArrivals.txt");
                    Console.WriteLine($"Daily arrivals have been written and appended to {f.FullName}");
                }
            }

            var x = Hotel.GetDailyOccupancy(); // Using var instead of explicity breaking out the tuple since it's simpler
            if (x.Item1.Count == 0)
            {
                Console.WriteLine($"No daily occupancies to report.");
            } else
            {
                Operational.FetchDailyOccupancy(x.Item1, x.Item2);
                if (File.Exists("DailyOccupancy.txt"))
                {
                    FileInfo f = new("DailyOccupancy.txt");
                    Console.WriteLine($"Daily occupancy has been written and appended to {f.FullName}");
                }
            }
        }
        void IssuePenalties()
        {
            /*
             * Iterates over a list of reservations returned by GetPastDueReservations(),
             * a function of the Hotel class. Since all the reservations returned are known
             * to be past due, the cancellation function is called and the reservation is
             * canceled and charged if applicable.
             */
            List<Reservation> reservations = Hotel.GetPastDueReservations();
            foreach (Reservation reservation in reservations)
            {
                reservation.CancelReservation();
            }
            Console.WriteLine("Penalties have been issued.");
        }

        Console.Write(
        "\nWelcome to the Ophelias Oasis Hotel Management System!\n" +
        "Type help to get a full list of commands or enter a command.\n" +
        "Command: ");
        while (true)
        {
            /*
             * This is the main administrator loop.
             * The following are valid operations:
             * 
             *      generate management report: 
             *          Generates a series of report detailing the expected occupancy, expected room income,
             *          and the losses incurred due to incentive reservations. For more information see the
             *          GenerateManagementReport() function.
             *          
             *      generate operational report:
             *          Generates a series of reports detailing the daily arrivals and daily occupancy.
             *          For more information see the GenerateOperationalReports() function.
             *          
             *      generate accommodation bills:
             *          Generates the accommodation bills for reservations arriving that day. These will
             *          be handed out upon checkout (No process for this since there is no printer
             *          connected to this application). For more information see the GenerateAccommodationBills() 
             *          function.
             *      
             *      notify pending payments:
             *          Generates an email for any outstanding payments within the payment window for
             *          60-day-in-advance reservations. For more information see the NotifyOutstandingPayments()
             *          function.
             *          
             *      issue penalties:
             *          Issues penalties to reservations that end up as "no-show". Furthermore, it will
             *          also charge them if applicable. This is mostly just to pick up any reservations 
             *          that are not canceled by users or canceled as a result of attempting to checkin
             *          or pay for a reservation that would be market as "no-show". For more information 
             *          see the IssuePenalties() function.
             *          
             *      checkin guest:
             *          Checks in the guest and assigns them a room number. For more information see the 
             *          CheckIn() function.
             *          
             *      checkout guest:
             *          Checks a guest out and marks their reservation as ended. The room number is
             *          not removed for historical purposes. For more information see the CheckOut() 
             *          function.
             *          
             *      set rate:
             *          Set rate allows employees to set a specific rate for a specific day. This
             *          rate takes effect on the date set. For more information see the SetFutureBaseRate() 
             *          function.
             *          
             *      Q or Q:
             *          Returns to the main loop for choosing either the Guest or Admin flow.
             */
            Hotel.CheckBaseRate();
            string? input = Console.ReadLine();
            switch (input)
            {
                case "help": help(); break; // Gets help text
                case "generate management report": GenerateManagementReports(); break; // Generates management reports and outputs to text files
                case "generate operational report": GenerateOperationalReports(); break;  // Generates operational reports and outputs to text files
                case "generate accommodation bills": GenerateAccommodationBills(); break;  // Generates accommodation bills and outputs to a text file
                case "notify pending payments": NotifyOutstandingPayments(); break; // Generates an email and outputs to a text file
                case "issue penalties": IssuePenalties(); break; // Cancels "no-show" reservations and charges their accounts
                case "checkin guest": CheckIn(); break; // Checks a guest in and assigns a room
                case "checkout guest": CheckOut(); break; // Checks out a guest and marks their reservation as ended
                case "set rate": SetFutureBaseRate(); break; // Allows employees to configure base rates
                case "Q": return; // Quit to mode loop
                case "q": return; // Quit to mode loop
                default: Console.WriteLine("Unknown command, enter help for more inforamtion."); break;
            }
            Console.Write("\nCommand: ");
        }

    }
    private static void Main()
    {
        if (!File.Exists("database.sqlite3") || new FileInfo("database.sqlite3").Length == 0)
        {
            /*
             *  Checks to see if the databse is created. If the database file is missing, that means
             *  it has not been initialized. Upon the initialization process, the tables are created
             *  and the rooms table is populated with 45 rooms. This is a preconfigured value within
             *  the InitializeRoomsTable() function since there was no requirement to make this configurable.
             */
            SQLiteConnection.CreateFile("database.sqlite3");
            using Database Manager = new();
            Manager.InitializeTables();
            Manager.InitializeRoomsTable();
        }
        if (!Hotel.CheckBaseRate())
        {
            // Checks to see if the base rate is configured, if not a warning will be shown.
            Console.WriteLine("No base rate is configured. As a result reservations cannot be made until one is configured.");
        }

        bool run = true;
        while (run)
        {
            // Main loop for checking if the person is a customer or employee.
            Console.Write(
                "Are you an employee or customer?\n" +
                "1. Employee\n" +
                "2. Customer/ Guest\n" +
                ": "
            );
            switch (Console.ReadLine().ToUpper()) // Using .ToUpper() to support "q" without having to write a case for it.
            {
                case "1": AdminMode(); break; // Enter employee (administrative) mode
                case "2": GuestMode(); break; // Enter guest (customer) mode
                case "Q": run = false; break; // Quit
                default: Console.WriteLine("You must either specify 1 for Employee, 2 for Customer/ Guest, or Q to quit.\n\n"); break;
            }
        }
        Console.WriteLine("Shutting system down.");
    }
}