ersatztv/ErsatzTV.Core.Tests/Scheduling/CustomOrderContentTests.cs

using System;
using System.Collections.Generic;
using System.Linq;
using ErsatzTV.Core.Domain;
using ErsatzTV.Core.Scheduling;
using FluentAssertions;
using NUnit.Framework;
using static LanguageExt.Prelude;

namespace ErsatzTV.Core.Tests.Scheduling
{
    public class CustomOrderContentTests
    {
        [Test]
        public void MediaItems_Should_Sort_By_CustomOrder()
        {
            Collection collection = CreateCollection(10);
            List<MediaItem> contents = Episodes(10);
            var state = new CollectionEnumeratorState();

            var customOrderContent = new CustomOrderCollectionEnumerator(collection, contents, state);

            for (var i = 10; i >= 1; i--)
            {
                customOrderContent.Current.IsSome.Should().BeTrue();
                customOrderContent.Current.Map(x => x.Id).IfNone(-1).Should().Be(i);
                customOrderContent.MoveNext();
            }
        }

        [Test]
        public void State_Index_Should_Increment()
        {
            Collection collection = CreateCollection(10);
            List<MediaItem> contents = Episodes(10);
            var state = new CollectionEnumeratorState();

            var customOrderContent = new CustomOrderCollectionEnumerator(collection, contents, state);

            for (var i = 0; i < 10; i++)
            {
                customOrderContent.State.Index.Should().Be(i % 10);
                customOrderContent.MoveNext();
            }
        }

        [Test]
        public void State_Should_Impact_Iterator_Start()
        {
            Collection collection = CreateCollection(10);
            List<MediaItem> contents = Episodes(10);
            var state = new CollectionEnumeratorState { Index = 5 };

            var customOrderContent = new CustomOrderCollectionEnumerator(collection, contents, state);

            for (var i = 5; i >= 1; i--)
            {
                customOrderContent.Current.IsSome.Should().BeTrue();
                customOrderContent.Current.Map(x => x.Id).IfNone(-1).Should().Be(i);
                customOrderContent.State.Index.Should().Be(5 - i + 5); // 5 through 10
                customOrderContent.MoveNext();
            }
        }

        private static Collection CreateCollection(int episodeCount)
        {
            var collection = new Collection { CollectionItems = new List<CollectionItem>() };

            for (var i = 1; i <= episodeCount; i++)
            {
                collection.CollectionItems.Add(
                    new CollectionItem
                    {
                        MediaItemId = i,
                        // reverse order
                        CustomIndex = episodeCount - i
                    });
            }

            return collection;
        }


        private static List<MediaItem> Episodes(int count) =>
            Range(1, count).Map(
                    i => (MediaItem) new Episode
                    {
                        Id = i,
                        EpisodeMetadata = new List<EpisodeMetadata>
                        {
                            new()
                            {
                                ReleaseDate = new DateTime(2020, 1, i)
                            }
                        }
                    })
                .Reverse()
                .ToList();
    }
}