pr04 entity exam

using _01.EntityFrameworkMappings;
using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Xml;

namespace _04.ImportUsersAndTheirGamesFromXML
{
    class ImportFromXML
    {
        static void Main()
        {
            var ctx = new DiabloEntities();
            var xmlDoc = new XmlDocument();
            xmlDoc.Load("../../users-and-games.xml");

            XmlNodeList users = xmlDoc.SelectNodes("/users/user");

            foreach (XmlNode userInfo in users)
            {
                var newUser = GetUserInfo(userInfo);

                try
                {
                    ProcessUser(newUser, ctx, userInfo);
                }
                catch (InvalidOperationException ex)
                {
                    Console.WriteLine(ex.Message);
                }
            }
        }

        private static void ProcessUser(User newUser, DiabloEntities ctx, XmlNode userInfo)
        {
            if (ctx.Users.FirstOrDefault(u => u.Username == newUser.Username) != null)
            {
                var message = string.Format("User {0} already exists", newUser.Username);
                throw new InvalidOperationException(message);
            }

            Console.WriteLine("Successfully added user {0}", newUser.Username);

            var userGames = userInfo.SelectNodes("games/game");
            foreach (XmlNode userGame in userGames)
            {
                var gameName = userGame.SelectSingleNode("game-name").InnerText;

                if (ctx.Games.FirstOrDefault(g => g.Name == gameName) == null)
                {
                    var message = string.Format("No such game: {0}", gameName);
                    throw new InvalidOperationException(message);
                }

                var gameId = ctx.Games.FirstOrDefault(g => g.Name == gameName).Id;
                var charName = userGame.SelectSingleNode("character").Attributes["name"].Value;
                var charCash = decimal.Parse(userGame.SelectSingleNode("character").Attributes["cash"].Value);
                var charLevel = int.Parse(userGame.SelectSingleNode("character").Attributes["level"].Value);
                var joinedOn = DateTime.ParseExact(
                    userGame.SelectSingleNode("joined-on").InnerText,
                    "dd/MM/yyyy", CultureInfo.InvariantCulture);

                var newUserGame = new UsersGame()
                {
                    GameId = gameId,
                    Character = new Character()
                    {
                        Name = charName
                    },
                    Level = charLevel,
                    Cash = charCash,
                    JoinedOn = joinedOn
                };

                ctx.UsersGames.Add(newUserGame);
                Console.WriteLine("User {0} successfully added to game {1}", newUser.Username, gameName);
            }

            ctx.Users.Add(newUser);
            ctx.SaveChanges();
        }

        private static User GetUserInfo(XmlNode user)
        {
            string firstName = null;
            if (user.Attributes["first-name"] != null)
            {
                firstName = user.Attributes["first-name"].Value;
            }

            string lastName = null;
            if (user.Attributes["last-name"] != null)
            {
                lastName = user.Attributes["last-name"].Value;
            }

            var username = user.Attributes["username"].Value;

            string email = null;
            if (user.Attributes["email"] != null)
            {
                email = user.Attributes["email"].Value;
            }

            var isDeleted = user.Attributes["is-deleted"].Value == "1";
            var ipAddress = user.Attributes["ip-address"].Value;
            var registrationDate = DateTime.ParseExact(
                user.Attributes["registration-date"].Value,
                "dd/MM/yyyy", CultureInfo.InvariantCulture);

            return new User()
            {
                FirstName = firstName,
                LastName = lastName,
                Email = email,
                IpAddress = ipAddress,
                IsDeleted = isDeleted,
                RegistrationDate = registrationDate,
                Username = username
            };
        }
    }
}