using Gameboard.ShogiUI.Sockets.Repositories;
using Microsoft.AspNetCore.Authentication;
using System.Linq;
using System.Security.Claims;
using System.Threading.Tasks;

namespace Gameboard.ShogiUI.Sockets
{
  /// <summary>
  /// Standardizes the claims from third party issuers. Also registers new msal users in the database.
  /// </summary>
  public class ShogiUserClaimsTransformer : IClaimsTransformation
  {
    private static readonly string MsalUsernameClaim = "preferred_username";
    private readonly IGameboardRepository gameboardRepository;

    public ShogiUserClaimsTransformer(IGameboardRepository gameboardRepository)
    {
      this.gameboardRepository = gameboardRepository;
    }

    public async Task<ClaimsPrincipal> TransformAsync(ClaimsPrincipal principal)
    {
      var nameClaim = principal.Claims.FirstOrDefault(c => c.Type == MsalUsernameClaim);
      if (nameClaim != default)
      {
        var user = await gameboardRepository.ReadUser(nameClaim.Value);
        if (user == null)
        {
          var newUser = Models.User.CreateMsalUser(nameClaim.Value);
          var success = await gameboardRepository.CreateUser(newUser);
          if (success) user = newUser;
        }

        if (user != null)
        {
          return new ClaimsPrincipal(user.CreateClaimsIdentity());
        }
      }
      return principal;
    }
  }
}