using Azure.Core;
using SharepointToolbox.Web.Services;

namespace SharepointToolbox.Web.Infrastructure.Auth;

/// <summary>
/// TokenCredential backed by the circuit's ISessionManager.
/// Lets GraphServiceClient call GetTokenAsync transparently using our refresh-token flow.
/// </summary>
public class SessionTokenCredential : TokenCredential
{
    private readonly ISessionManager _sessionManager;

    public SessionTokenCredential(ISessionManager sessionManager) { _sessionManager = sessionManager; }

    public override async ValueTask<AccessToken> GetTokenAsync(TokenRequestContext requestContext, CancellationToken ct)
    {
        var scope = requestContext.Scopes.FirstOrDefault() ?? "https://graph.microsoft.com/.default";
        var (token, expiresAt) = await _sessionManager.GetAccessTokenWithExpiryAsync(scope, ct);
        return new AccessToken(token, expiresAt);
    }

    public override AccessToken GetToken(TokenRequestContext requestContext, CancellationToken ct)
        => GetTokenAsync(requestContext, ct).AsTask().GetAwaiter().GetResult();
}