Kavita/API/Services/Store/UserContext.cs

using API.Entities.Progress;
using Kavita.Common;

namespace API.Services.Store;
#nullable enable

public interface IUserContext
{
    /// <summary>
    /// Gets the current authenticated user's ID.
    /// Returns null if user is not authenticated or on [AllowAnonymous] endpoint.
    /// </summary>
    int? GetUserId();

    /// <summary>
    /// Gets the current authenticated user's ID.
    /// Throws KavitaException if user is not authenticated.
    /// </summary>
    int GetUserIdOrThrow();

    /// <summary>
    /// Gets the current authenticated user's username.
    /// Returns null if user is not authenticated.
    /// </summary>
    /// <remarks>Warning! Username's can contain .. and /, do not use folders or filenames explicitly with the Username</remarks>
    string? GetUsername();

    /// <summary>
    /// Gets the authentication method used (JWT, Auth Key, OIDC).
    /// </summary>
    AuthenticationType GetAuthenticationType();

    /// <summary>
    /// Returns true if the current user is authenticated.
    /// </summary>
    bool IsAuthenticated { get; }
}

public class UserContext : IUserContext
{
    private int? _userId;
    private string? _username;
    private AuthenticationType _authType;

    public int? GetUserId() => _userId;

    public int GetUserIdOrThrow()
    {
        return _userId ?? throw new KavitaException("User is not authenticated");
    }

    public string? GetUsername() => _username;

    public AuthenticationType GetAuthenticationType() => _authType;

    public bool IsAuthenticated { get; private set; }

    // Internal method used by middleware to set context
    internal void SetUserContext(int userId, string username, AuthenticationType authType)
    {
        _userId = userId;
        _username = username;
        _authType = authType;
        IsAuthenticated = true;
    }

    internal void Clear()
    {
        _userId = null;
        _username = null;
        _authType = AuthenticationType.Unknown;
        IsAuthenticated = false;
    }
}