namespace Zcbot.WindowsNode.Tests;

public sealed class JobPageViewModelTests
{
    [Fact]
    public void Refresh_PopulatesJobsFormatsStateAndSelectsTheFirstItem()
    {
        var active = Snapshot("software_running", "正在生成图表", minutesAgo: 2);
        var succeeded = Snapshot("succeeded", "历史任务", minutesAgo: 10);
        var viewModel = new JobPageViewModel(new FakeJobMonitorService(active, succeeded));

        viewModel.Refresh();

        Assert.Equal(2, viewModel.Jobs.Count);
        Assert.Same(viewModel.Jobs[0], viewModel.SelectedJob);
        Assert.Equal("软件执行中", viewModel.Jobs[0].StageText);
        Assert.StartsWith("已执行 02:", viewModel.Jobs[0].ProgressText);
        Assert.Equal("活动任务 1 个 · 最近记录 2 条", viewModel.Summary);
        Assert.Contains(active.JobId.ToString(), viewModel.SelectedDetail);
    }

    [Fact]
    public void Refresh_PreservesSelectionByJobIdAcrossSnapshots()
    {
        var first = Snapshot("accepted", "第一项", minutesAgo: 3);
        var second = Snapshot("failed", "第二项", minutesAgo: 2);
        var service = new FakeJobMonitorService(first, second);
        var viewModel = new JobPageViewModel(service);
        viewModel.Refresh();
        viewModel.SelectedJob = viewModel.Jobs[1];

        service.Snapshots = [
            second with { Detail = "更新后的错误" },
            first,
        ];
        viewModel.Refresh();

        Assert.Equal(second.JobId, viewModel.SelectedJob?.JobId);
        Assert.Contains("更新后的错误", viewModel.SelectedDetail);
        Assert.Equal("error", viewModel.SelectedJob?.Tone);
    }

    [Fact]
    public void Refresh_ReportsReadFailuresWithoutDroppingTheCurrentList()
    {
        var service = new FakeJobMonitorService(Snapshot("accepted", "任务", 1));
        var viewModel = new JobPageViewModel(service);
        viewModel.Refresh();
        service.Failure = new IOException("locked");

        viewModel.Refresh();

        Assert.Single(viewModel.Jobs);
        Assert.Contains("locked", viewModel.Summary);
    }

    private static JobDisplaySnapshot Snapshot(
        string stage,
        string title,
        int minutesAgo)
    {
        var updatedAt = DateTimeOffset.UtcNow.AddMinutes(-minutesAgo);
        return new JobDisplaySnapshot(
            Guid.NewGuid(),
            "origin.plot@v2",
            title,
            "input.csv",
            stage,
            stage == "succeeded" ? 100 : 25,
            title,
            updatedAt.AddMinutes(-1),
            updatedAt,
            stage == "succeeded");
    }

    private sealed class FakeJobMonitorService(params JobDisplaySnapshot[] snapshots)
        : IJobMonitorService
    {
        internal IReadOnlyList<JobDisplaySnapshot> Snapshots { get; set; } = snapshots;
        internal Exception? Failure { get; set; }

        public IReadOnlyList<JobDisplaySnapshot> ReadSnapshots(int limit = 50)
        {
            if (Failure is not null) throw Failure;
            return Snapshots;
        }
    }
}