ophelias-oasis/OpheliasOasis/Managers/DatabaseManager.cs

using System.Data.SQLite;
using Ophelias.Models;

namespace Ophelias.Managers
{
    internal class DatabaseManager : IDisposable
    {
        internal SQLiteConnection con = new SQLiteConnection("DataSource=database.sqlite3;Version=3;");

        internal DatabaseManager()
        {
            Connect();
        }
        internal void Connect()
        {
            con.Open();
        }
        internal void Close()
        {
            con.Close();
            con.Dispose();
        }
        internal void InitializeTables()
        {
            string tableCommands =
                @"CREATE TABLE IF NOT EXISTS [transactions] (
                  [ID] INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
                  [Rate] INTEGER NOT NULL,
                  [Owed] INTEGER NOT NULL,
                  [Penalty] INTEGER NULL,
                  [Multiplier] INTEGER NOT NULL,
                  [RefundAmount] INTEGER NOT NULL,
                  [PayBy] TEXT NOT NULL,
                  [PaidOn] TEXT NULL);

                CREATE TABLE IF NOT EXISTS [reservations] (
                  [ID] INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
                  [RoomID] INTEGER NOT NULL,
                  [GuestID] INTEGER NOT NULL,
                  [TransactionID] INTEGER NOT NULL,
                  [IsNoShow] BOOLEAN NOT NULL CHECK ([IsNoShow] IN (0,1)),
                  [Type] INTEGER NOT NULL CHECK ([Type] IN (0,1,2,3)),
                  [Status] INTEGER NOT NULL CHECK ([Status] IN (0,1,2,3)),
                  [CreationDate] TEXT NOT NULL,
                  [StartDate] TEXT NOT NULL,
                  [EndDate] TEXT NOT NULL,
                  [CheckIn] TEXT NOT NULL,
                  [CheckOut] TEXT NOT NULL,
                  [DateChanged] TEXT NOT NULL,
                  FOREIGN KEY ([RoomID]) REFERENCES ROOMS(ID),
                  FOREIGN KEY ([GuestID]) REFERENCES GUESTS(ID),
                  FOREIGN KEY ([TransactionID]) REFERENCES TRANSACTIONS(ID));

                CREATE TABLE IF NOT EXISTS [guests] (
                  [ID] INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
                  [Fname] TEXT NOT NULL,
                  [Lname] TEXT NOT NULL,
                  [Email] TEXT NOT NULL,
                  [CreditCard] TEXT NULL,
                  [Expiration] TEXT NULL,
                  [CCV] TEXT NULL);
  
                CREATE TABLE IF NOT EXISTS [rooms] (
                  [ID] INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
                  [Occupied] BOOLEAN NOT NULL CHECK ([Occupied] IN (0,1)));

                CREATE TABLE IF NOT EXISTS [rates] (
                  [ID] INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
                  [Rate] INTEGER NOT NULL,
                  [DateSet] TEXT NOT NULL);";

            using (SQLiteCommand cmd = con.CreateCommand())
            {
                cmd.CommandText = tableCommands;
                cmd.ExecuteNonQuery();
            }
        }

        internal void InitializeRoomsTable()
        {
            using (SQLiteCommand cmd = con.CreateCommand())
            {
                for (int i = 1; i < 46; i++)
                {
                    cmd.CommandText = $"INSERT INTO ROOMS (Occupied) VALUES (0);";
                    cmd.ExecuteNonQuery();
                }
            }

            // Initialize Rooms

        }
        public void Dispose()
        {
            Close();
        }
    }

    internal static class DatabaseFunctions
    {

    }
    internal static class QueryBuilder
    {

        internal static string? UpdateTransaction(int id,
            double? Rate = null, double? Owed = null, double? Penalty = null,
            double? Multiplier = null, double? Refund = null,
            DateTime? PayBy = null, DateTime? PaidOn = null)
        {
            List<string> queryComponents = new List<string>();
            string query = "UPDATE transactions SET";

            if (Rate.HasValue)
                queryComponents.Add($"Rate = {Rate}");
            if (Owed.HasValue)
                queryComponents.Add($"Owed = {Owed}");
            if (Penalty.HasValue)
                queryComponents.Add($"Penalty = {Penalty}");
            if (Multiplier.HasValue)
                queryComponents.Add($"Multiplier = {Multiplier}");
            if (Refund.HasValue)
                queryComponents.Add($"Refund = {Refund}");
            if (PayBy.HasValue)
                queryComponents.Add($"PaidBy = {PayBy.Value.ToString("yyyy-MM-dd")}");
            if (PaidOn.HasValue)
                queryComponents.Add($"PaidOn = {PaidOn.Value.ToString("yyyy-MM-dd")}");

            if (queryComponents.Count == 0)
                query += " " + string.Join(", ", queryComponents) + " " + $"WHERE ID = {id};";
            else
                return null;

            return query;
        }

        internal static string? UpdateReservation(int id,
            int? roomid = null, int? guestid = null, int? transactionid = null, bool? isnoshow = null, ReservationType? type = null,
            ReservationStatus? status = null, DateTime? creationdate = null, DateTime? startdate = null, DateTime? enddate = null,
            DateTime? checkin = null, DateTime? checkout = null, DateTime? datechanged = null)
        {
            List<string> queryComponents = new List<string>();
            string query = "UPDATE reservations SET";

            if (roomid.HasValue)
                queryComponents.Add($"RoomID = {roomid}");
            if (guestid.HasValue)
                queryComponents.Add($"GuestID = {guestid}");
            if (transactionid.HasValue)
                queryComponents.Add($"TransactionID = {transactionid}");
            if (isnoshow.HasValue)
                queryComponents.Add($"IsNoShow = {Convert.ToInt32(isnoshow)}");
            if (type.HasValue)
                queryComponents.Add($"Type = {(int)type}");
            if (status.HasValue)
                queryComponents.Add($"Type = {(int)status}");
            if (creationdate.HasValue)
                queryComponents.Add($"CreationDate = {creationdate.Value.ToString("yyyy-MM-dd")}");
            if (startdate.HasValue)
                queryComponents.Add($"StartDate = {startdate.Value.ToString("yyyy-MM-dd")}");
            if (enddate.HasValue)
                queryComponents.Add($"EndDate = {enddate.Value.ToString("yyyy-MM-dd")}");
            if (checkin.HasValue)
                queryComponents.Add($"CheckIn = {checkin.Value.ToString("yyyy-MM-dd")}");
            if (checkout.HasValue)
                queryComponents.Add($"CheckOut = {checkout.Value.ToString("yyyy-MM-dd")}");
            if (datechanged.HasValue)
                queryComponents.Add($"CheckOut = {datechanged.Value.ToString("yyyy-MM-dd")}");

            if (queryComponents.Count == 0)
                query += " " + string.Join(", ", queryComponents) + " " + $"WHERE ID = {id};";
            else
                return null;

            return query;
        }

        internal static string CreateTransaction(double Rate, double Owed, double Penalty,
            double Multiplier, double Refund, bool isLate,
            bool PaidOff, DateTime PaidBy, DateTime? PaidOn = null)
        {

            return @$"INSERT INTO transactions (Rate, Owed, Penalty, Multiplier, Refund, IsLate, PaidOff, PaidBy, PaidOn)
                              VALUES ({Rate}, {Owed}, {Penalty}, {Multiplier}, {Refund}, {isLate}, {PaidOff}, {PaidBy}, {PaidOn});";
        }

        internal static string CreateReservation(int roomid, int guestid, int transactionid, bool isnoshow, ReservationType type,
            ReservationStatus status, DateTime creationdate, DateTime startdate, DateTime enddate,
            DateTime checkin, DateTime checkout, DateTime datechanged)
        {
            return @$"INSERT INTO reservations (RoomID, GuestID, TransactionID, IsNoShow, Type, Status, CreationDate, StartDate, EndDate, CheckIn, CheckOut, DateChanged)
                              VALUES ({roomid}, {guestid}, {transactionid}, {isnoshow}, {status}, {creationdate}, {startdate}, {enddate}, {checkin}, {checkout}, {datechanged});";
        }

        internal static string CreateGuest(string FirstName, string LastName, string Email, string? CreditCard, string? Expiration, string? CCV)
        {
            if (CreditCard != null && Expiration != null && CCV != null)
                return $@"INSERT INTO guests (Fname, Lname, Email) VALUES ({FirstName}, {LastName}, {Email});";
            else
                return $@"INSERT INTO guests (Fname, Lname, Email, CreditCard, Expiration, CCV) VALUES ({FirstName}, {LastName}, {Email}, {CreditCard}, {Expiration}, {CCV});";
        }
    }
}