namespace NATS.Server.Core.Tests;

// Go reference: server/client.go (maxFlushPending, pcd, flush signal coalescing)

public class FlushCoalescingTests
{
    [Fact]
    public void MaxFlushPending_defaults_to_10()
    {
        // Go reference: server/client.go maxFlushPending constant
        NatsClient.MaxFlushPending.ShouldBe(10);
    }

    [Fact]
    public void ShouldCoalesceFlush_true_when_below_max()
    {
        // When flush signals pending is below MaxFlushPending, coalescing is allowed
        // Go reference: server/client.go fsp < maxFlushPending check
        var pending = 5;
        var shouldCoalesce = pending < NatsClient.MaxFlushPending;
        shouldCoalesce.ShouldBeTrue();
    }

    [Fact]
    public void ShouldCoalesceFlush_false_when_at_max()
    {
        // When flush signals pending reaches MaxFlushPending, force flush
        var pending = NatsClient.MaxFlushPending;
        var shouldCoalesce = pending < NatsClient.MaxFlushPending;
        shouldCoalesce.ShouldBeFalse();
    }

    [Fact]
    public void ShouldCoalesceFlush_false_when_above_max()
    {
        // Above max, definitely don't coalesce
        var pending = NatsClient.MaxFlushPending + 5;
        var shouldCoalesce = pending < NatsClient.MaxFlushPending;
        shouldCoalesce.ShouldBeFalse();
    }

    [Fact]
    public void FlushCoalescing_constant_matches_go_reference()
    {
        // Go reference: server/client.go maxFlushPending = 10
        // Verify the constant is accessible and correct
        NatsClient.MaxFlushPending.ShouldBeGreaterThan(0);
        NatsClient.MaxFlushPending.ShouldBeLessThanOrEqualTo(100);
    }
}