using ItWorx.KnowledgeHub.Domain.Knowledge;

namespace ItWorx.KnowledgeHub.Domain.Tests;

public sealed class SortKeyTests
{
    [Fact]
    public void Next_produces_a_key_that_sorts_after_the_previous_one()
    {
        var first = SortKey.First();
        var second = SortKey.Next(first);
        var third = SortKey.Next(second);

        Assert.True(string.CompareOrdinal(first.Value, second.Value) < 0);
        Assert.True(string.CompareOrdinal(second.Value, third.Value) < 0);
    }

    [Fact]
    public void Between_produces_a_key_strictly_between_two_others()
    {
        var lower = SortKey.First();
        var upper = SortKey.Next(lower);
        var middle = SortKey.Between(lower, upper);

        Assert.True(string.CompareOrdinal(lower.Value, middle.Value) < 0);
        Assert.True(string.CompareOrdinal(middle.Value, upper.Value) < 0);
    }

    [Fact]
    public void All_keys_share_the_same_fixed_width_for_stable_ordinal_comparison()
    {
        var keys = new[] { SortKey.First(), SortKey.Next(SortKey.First()) };

        Assert.All(keys, key => Assert.Equal(keys[0].Value.Length, key.Value.Length));
    }
}