using Microsoft.Extensions.Options;

namespace ZB.MOM.WW.ScadaBridge.NotificationOutbox.Tests;

/// <summary>
/// Tests for the options validator: <see cref="NotificationOutboxOptions"/> had no
/// registered validator before this — the dispatch/purge/KPI cadences and the
/// delivered-throughput KPI window (<see cref="NotificationOutboxOptions.DeliveredKpiWindow"/>)
/// could be zero/negative with no boot-time signal, which would spin an Akka
/// scheduler or — because <c>NotificationOutboxKpiSampleSource</c> divides by
/// <c>DeliveredKpiWindow</c> to rescale onto <c>KpiHistoryOptions.SampleInterval</c>
/// — divide by zero. <see cref="NotificationOutboxOptions.MaxParallelDeliveries"/>
/// is validated on its BASE property, not the clamped
/// <see cref="NotificationOutboxOptions.ResolvedMaxParallelDeliveries"/>, so a
/// misconfigured non-positive value fails fast instead of silently clamping to 1.
/// </summary>
public class NotificationOutboxOptionsValidatorTests
{
    private static ValidateOptionsResult Validate(NotificationOutboxOptions options) =>
        new NotificationOutboxOptionsValidator().Validate(Options.DefaultName, options);

    /// <summary>Verifies that the default options are valid.</summary>
    [Fact]
    public void DefaultOptions_AreValid()
    {
        var result = Validate(new NotificationOutboxOptions());
        Assert.True(result.Succeeded, result.FailureMessage);
    }

    /// <summary>Verifies that a zero dispatch interval is rejected.</summary>
    [Fact]
    public void ZeroDispatchInterval_IsRejected()
    {
        var result = Validate(new NotificationOutboxOptions { DispatchInterval = TimeSpan.Zero });
        Assert.True(result.Failed);
        Assert.Contains("DispatchInterval", result.FailureMessage);
    }

    /// <summary>Verifies that a zero dispatch batch size is rejected.</summary>
    [Fact]
    public void ZeroDispatchBatchSize_IsRejected()
    {
        var result = Validate(new NotificationOutboxOptions { DispatchBatchSize = 0 });
        Assert.True(result.Failed);
        Assert.Contains("DispatchBatchSize", result.FailureMessage);
    }

    /// <summary>Verifies that a zero stuck-age threshold is rejected.</summary>
    [Fact]
    public void ZeroStuckAgeThreshold_IsRejected()
    {
        var result = Validate(new NotificationOutboxOptions { StuckAgeThreshold = TimeSpan.Zero });
        Assert.True(result.Failed);
        Assert.Contains("StuckAgeThreshold", result.FailureMessage);
    }

    /// <summary>Verifies that a zero terminal-row retention is rejected.</summary>
    [Fact]
    public void ZeroTerminalRetention_IsRejected()
    {
        var result = Validate(new NotificationOutboxOptions { TerminalRetention = TimeSpan.Zero });
        Assert.True(result.Failed);
        Assert.Contains("TerminalRetention", result.FailureMessage);
    }

    /// <summary>Verifies that a zero purge interval is rejected.</summary>
    [Fact]
    public void ZeroPurgeInterval_IsRejected()
    {
        var result = Validate(new NotificationOutboxOptions { PurgeInterval = TimeSpan.Zero });
        Assert.True(result.Failed);
        Assert.Contains("PurgeInterval", result.FailureMessage);
    }

    /// <summary>Verifies that a zero delivered-KPI window is rejected.</summary>
    [Fact]
    public void ZeroDeliveredKpiWindow_IsRejected()
    {
        var result = Validate(new NotificationOutboxOptions { DeliveredKpiWindow = TimeSpan.Zero });
        Assert.True(result.Failed);
        Assert.Contains("DeliveredKpiWindow", result.FailureMessage);
    }

    /// <summary>Verifies that a negative delivered-KPI window is rejected.</summary>
    [Fact]
    public void NegativeDeliveredKpiWindow_IsRejected()
    {
        var result = Validate(new NotificationOutboxOptions { DeliveredKpiWindow = TimeSpan.FromSeconds(-1) });
        Assert.True(result.Failed);
        Assert.Contains("DeliveredKpiWindow", result.FailureMessage);
    }

    /// <summary>Verifies that a zero maximum parallel deliveries value is rejected.</summary>
    [Fact]
    public void ZeroMaxParallelDeliveries_IsRejected()
    {
        var result = Validate(new NotificationOutboxOptions { MaxParallelDeliveries = 0 });
        Assert.True(result.Failed);
        Assert.Contains("MaxParallelDeliveries", result.FailureMessage);
    }
}