#nullable enable

using System;

using System.Linq;

using System.ComponentModel.DataAnnotations;

using Faithlife.FakeData;

​

public sealed class UserRecord

{

    [Key]

    public long UserId { get; set; }

​

    [Required, StringLength(100)]

    public string Name { get; set; } = "";

​

    [RegularExpression(@"^[a-zA-Z0-9_]+$")]

    public string? Alias { get; set; }

}

​

public sealed class UserRoleRecord

{

    [Key]

    public long UserRoleId { get; set; }

    public long UserId { get; set; }

​

    public int Role { get; set; }

}

​

public sealed class UserDatabaseContext : FakeDatabaseContext

{

    public UserDatabaseContext()

    {

        Users = CreateTable<UserRecord>();

        UserRoles = CreateTable<UserRoleRecord>();

    }

​

    public FakeDatabaseTable<UserRecord> Users { get; }

​

    public FakeDatabaseTable<UserRoleRecord> UserRoles { get; }

}

​

public class Program

{

    public static void Main()

    {

        var database = FakeDatabase.Create<UserDatabaseContext>();

​

        using var context = database.Lock();

​

        var alice = context.Users.Add(new UserRecord { Name = "Alice", Alias = "4l1c3" });

        var bob = context.Users.Add(new UserRecord { Name = "Bob", Alias = "b0b" });

        context.UserRoles.AddRange(new[]

        {

            new UserRoleRecord { UserId = alice.UserId, Role = 1 },

            new UserRoleRecord { UserId = bob.UserId, Role = 2 },

            new UserRoleRecord { UserId = bob.UserId, Role = 1 },

        });

        Console.WriteLine("Bob has ID {0}", bob.UserId);

​

        var aliases = context.Users.Select(x => x.Alias).Distinct();

        Console.WriteLine("Aliases: {0}", string.Join(", ", aliases));

​

        var namesWithRoleTwo =

            from user in context.Users

            join role in context.UserRoles on user.UserId equals role.UserId

            where role.Role == 2

            select user.Name;

        Console.WriteLine("Names with role 2: {0}", string.Join(", ", namesWithRoleTwo));

​

        int updated = context.Users.UpdateWhere(x => x.UserId == bob.UserId, x => x.Name = "Robert");

        Console.WriteLine("{0} records updated.", updated);

​

        int removed = context.Users.RemoveWhere(x => x.UserId == bob.UserId);

        Console.WriteLine("{0} records removed.", removed);

    }

}