using System.Security.Claims;
using System.Text.Encodings.Web;
using Microsoft.AspNetCore.Authentication;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;

namespace Musify.Api.Tests.TestSupport;

/// <summary>
/// Replaces the real JwtBearer handler in the test host: a request carrying the
/// <see cref="UserIdHeader"/> header authenticates as that user id, with no real token,
/// issuer or JWKS endpoint involved. A request without the header stays anonymous, so
/// endpoints under <c>.RequireAuthorization()</c> correctly answer 401.
/// </summary>
public sealed class FakeAuthenticationHandler(
    IOptionsMonitor<AuthenticationSchemeOptions> options,
    ILoggerFactory logger,
    UrlEncoder encoder)
    : AuthenticationHandler<AuthenticationSchemeOptions>(options, logger, encoder)
{
    public const string SchemeName = "Test";
    public const string UserIdHeader = "X-Test-User-Id";

    protected override Task<AuthenticateResult> HandleAuthenticateAsync()
    {
        if (!Request.Headers.TryGetValue(UserIdHeader, out var userId) || string.IsNullOrEmpty(userId))
            return Task.FromResult(AuthenticateResult.NoResult());

        var claims = new List<Claim> { new(ClaimTypes.NameIdentifier, userId!) };
        if (Request.Headers.TryGetValue("X-Test-User-Name", out var userName) && !string.IsNullOrEmpty(userName))
            claims.Add(new Claim(ClaimTypes.Name, userName!));

        var identity = new ClaimsIdentity(claims, SchemeName);
        var ticket = new AuthenticationTicket(new ClaimsPrincipal(identity), SchemeName);
        return Task.FromResult(AuthenticateResult.Success(ticket));
    }
}