using System.Security.Cryptography;
using Wingoria.Images.Client.V1;
using Wingoria.Images.Contracts.V1;

// Backend only. A private bootstrap owned by Authentication creates the client.
// Never put its endpoint or credential in source control, logs, a browser or Unity.
public sealed class ImagesConnectionTemplate(ImagesClient images)
{
    // For ordinary generation, prompt alone is enough. Provider and artistic
    // options are optional; no generation profile or financial fields are needed.
    public Task<ImageJob> SubmitGeneration(ManagedImageRequest request, string durableAttemptId,
        CancellationToken cancellationToken) =>
        images.GenerateManagedAsync(request, durableAttemptId, cancellationToken);

    public Task<ImageJob> SubmitEdit(ManagedImageRequest request, string durableAttemptId,
        CancellationToken cancellationToken) =>
        images.EditManagedAsync(request, durableAttemptId, cancellationToken);

    public async Task<byte[]> DownloadAndVerify(ImageJob terminalJob, int maximumBytes,
        CancellationToken cancellationToken)
    {
        if (terminalJob.Status != ImageJobStatus.Succeeded || terminalJob.Artifact is null)
            throw new InvalidOperationException("The job has no completed artifact.");
        var bytes = await images.DownloadArtifactAsync(terminalJob.Id, cancellationToken);
        if (bytes.Length == 0 || bytes.Length > maximumBytes)
            throw new InvalidDataException("The artifact size is outside the configured boundary.");
        var actual = SHA256.HashData(bytes);
        var expected = Convert.FromHexString(terminalJob.Artifact.Sha256);
        if (!CryptographicOperations.FixedTimeEquals(actual, expected))
            throw new InvalidDataException("The artifact checksum does not match the job receipt.");
        return bytes;
    }
}

// Run admission before paid work and verify the registered owner and scopes. Persist
// the idempotency key and job ID. Poll GetJobAsync with a bounded timeout. On an
// unknown submission outcome, reconcile instead of resubmitting.