using System;
using System.Collections.Immutable;
using System.Threading;
using System.Threading.Tasks;

namespace StellaOps.Cryptography.Kms;

public sealed partial class Fido2KmsClient
{
    public Task<KmsKeyMetadata> GetMetadataAsync(string keyId, CancellationToken cancellationToken = default)
    {
        ThrowIfDisposed();

        var now = _timeProvider.GetUtcNow();
        if (_cachedMetadata is not null && _metadataExpiresAt > now)
        {
            return Task.FromResult(_cachedMetadata);
        }

        var createdAt = _options.CreatedAt ?? _timeProvider.GetUtcNow();
        var version = new KmsKeyVersionMetadata(
            _options.CredentialId,
            KmsKeyState.Active,
            createdAt,
            null,
            Convert.ToBase64String(_subjectPublicKeyInfo),
            _curveName);

        _cachedMetadata = new KmsKeyMetadata(
            _options.CredentialId,
            KmsAlgorithms.Es256,
            KmsKeyState.Active,
            createdAt,
            ImmutableArray.Create(version));

        _metadataExpiresAt = now.Add(_metadataCacheDuration);
        return Task.FromResult(_cachedMetadata);
    }
}