using Big.Domain;

namespace Big.Application;

/// <summary>
/// Handles one acquired <c>RegistratieVerlopen</c> external-worker job (S-10a, ADR-0017): load the
/// registration the job correlates to and expire it to VERLOPEN — the 30-day document-wait timer fired
/// before the documents arrived, so the case is cancelled. Pure application logic over ports; it knows
/// nothing of Flowable. The polling loop that feeds it jobs lives in Infrastructure. Mirrors
/// <see cref="OpenZaakWorker"/>.
/// </summary>
public sealed class ExpireRegistrationWorker(IRegistrationStore store, IAclClient acl)
{
    /// <summary>
    /// Process the job. Idempotent and tolerant of races (§8.6, at-least-once delivery): a job whose
    /// registration is already resolved — a redelivered expiry (VERLOPEN), or one withdrawn/decided
    /// while it waited (INGETROKKEN/INGESCHREVEN/AFGEWEZEN) — is a no-op, so the job still completes
    /// rather than throwing into a redelivery loop. Only a still-open registration is expired. An
    /// unknown registration is an error: it throws, leaving the job un-completed for Flowable to redeliver.
    /// </summary>
    public async Task HandleAsync(RegistratieVerlopenJob job, CancellationToken ct = default)
    {
        ArgumentNullException.ThrowIfNull(job);

        var registration = await store.GetAsync(job.RegistrationId, ct)
            ?? throw new InvalidOperationException(
                $"No registration {job.RegistrationId} for RegistratieVerlopen job {job.JobId}.");

        // Only a still-open registration lapses; an already-resolved one (expired, or withdrawn/decided
        // while it waited) is left untouched so the job can complete without violating the aggregate.
        if (registration.Status is not (RegistrationStatus.Ingediend or RegistrationStatus.InBehandeling))
            return;

        // Cancel the ZGW zaak before advancing the aggregate (mirrors the approval path): if the ACL
        // call fails it throws, the aggregate stays open, and the job is redelivered (§8.6) — rather
        // than leaving the aggregate VERLOPEN while the zaak stays open. The status guard above stops a
        // redelivered job from cancelling the zaak twice (a second resultaat would be a 400). A
        // registration expired before its zaak was opened has nothing to cancel.
        if (registration.ZaakUrl is not null)
            await acl.CancelZaakAsync(registration.ZaakUrl, ct);

        registration.Expire();
        await store.SaveAsync(registration, ct);
    }
}