using Big.Application;
using Big.Domain;
using Big.Infrastructure;
using Microsoft.Extensions.Logging.Abstractions;

namespace Big.Tests;

public class OpenZaakJobProcessorTests
{
    /// <summary>A fake external-worker client: scripts the jobs to acquire and records completions.</summary>
    private sealed class FakeExternalWorkerClient(params OpenZaakJob[] jobs) : IExternalWorkerClient
    {
        public int AcquireCount { get; private set; }
        public List<(string JobId, Uri ZaakUrl)> Completed { get; } = [];

        public Task<IReadOnlyList<OpenZaakJob>> AcquireOpenZaakJobsAsync(int maxJobs, CancellationToken ct = default)
        {
            AcquireCount++;
            return Task.FromResult<IReadOnlyList<OpenZaakJob>>(jobs.Take(maxJobs).ToList());
        }

        public Task CompleteOpenZaakJobAsync(string jobId, Uri zaakUrl, CancellationToken ct = default)
        {
            Completed.Add((jobId, zaakUrl));
            return Task.CompletedTask;
        }
    }

    private static OpenZaakJobProcessor Processor(IExternalWorkerClient client, IRegistrationStore store, FakeAclClient acl)
        => new(client, new OpenZaakWorker(store, acl), NullLogger<OpenZaakJobProcessor>.Instance);

    [Fact]
    public async Task Acquires_a_job_opens_the_zaak_and_completes_it()
    {
        var registration = Registration.Submit("123456782");
        var store = new FakeRegistrationStore();
        store.Seed(registration);
        var client = new FakeExternalWorkerClient(new OpenZaakJob("job-1", registration.Id));
        var acl = new FakeAclClient();

        var acquired = await Processor(client, store, acl).PumpOnceAsync(5);

        Assert.Equal(1, acquired);
        var completed = Assert.Single(client.Completed);
        Assert.Equal("job-1", completed.JobId);
        Assert.Equal(FakeAclClient.DefaultZaakUrl, completed.ZaakUrl);
        Assert.Equal(FakeAclClient.DefaultZaakUrl, (await store.GetAsync(registration.Id))!.ZaakUrl);
    }

    [Fact]
    public async Task A_failing_job_is_left_uncompleted_for_flowable_to_redeliver()
    {
        var store = new FakeRegistrationStore();
        var acl = new FakeAclClient();
        // The job correlates to a registration that is not in the store, so the worker throws.
        var client = new FakeExternalWorkerClient(new OpenZaakJob("job-1", RegistrationId.New()));

        var acquired = await Processor(client, store, acl).PumpOnceAsync(5);

        Assert.Equal(1, acquired);
        Assert.Empty(client.Completed);
    }

    [Fact]
    public async Task Does_nothing_but_poll_when_there_are_no_jobs()
    {
        var store = new FakeRegistrationStore();
        var acl = new FakeAclClient();
        var client = new FakeExternalWorkerClient();

        var acquired = await Processor(client, store, acl).PumpOnceAsync(5);

        Assert.Equal(0, acquired);
        Assert.Equal(1, client.AcquireCount);
        Assert.Empty(client.Completed);
    }
}