using AyCode.Core.Serializers.Binaries;
using static AyCode.Core.Tests.TestModels.AcSerializerModels;

namespace AyCode.Core.Tests.Serialization;

[TestClass]
public class AcBinarySerializerPipeParallelTests
{
    [TestMethod]
    public async Task SerializeAndDeserialize_InParallelOnTwoTasks_ThroughPipe_RoundTrip()
    {
        var original = CreatePayload(200);
        var options = AcBinarySerializerOptions.Default;

        using var reader = new SegmentBufferReader(64);

        var deserializeTask = Task.Run(() =>
            (TestParentWithDateTimeItemCollection?)AcBinaryDeserializer.Deserialize(reader, typeof(TestParentWithDateTimeItemCollection), options));

        var serializeTask = Task.Run(async () =>
        {
            try
            {
                var binary = AcBinarySerializer.Serialize(original, options);
                var offset = 0;
                var chunkSizes = new[] { 7, 31, 13, 64, 5, 29 };

                for (var chunkIndex = 0; offset < binary.Length; chunkIndex++)
                {
                    var chunkSize = Math.Min(chunkSizes[chunkIndex % chunkSizes.Length], binary.Length - offset);
                    reader.Write(binary.AsSpan(offset, chunkSize));
                    offset += chunkSize;

                    if (chunkIndex % 4 == 0)
                        await Task.Yield();
                }
            }
            finally
            {
                reader.Complete();
            }
        });

        await Task.WhenAll(serializeTask, deserializeTask);

        var result = deserializeTask.Result;
        Assert.IsNotNull(result);
        AssertPayloadEquals(original, result);
    }

    [TestMethod]
    public async Task SerializeAndDeserialize_InParallelOnTwoTasks_WithMultiplePipelines_RoundTrip()
    {
        var options = AcBinarySerializerOptions.Default;

        var pipelines = Enumerable.Range(1, 8).Select(async seed =>
        {
            var original = CreatePayload(80 + seed * 10);

            using var reader = new SegmentBufferReader(32);

            var deserializeTask = Task.Run(() =>
                (TestParentWithDateTimeItemCollection?)AcBinaryDeserializer.Deserialize(reader, typeof(TestParentWithDateTimeItemCollection), options));

            var serializeTask = Task.Run(async () =>
            {
                try
                {
                    var binary = AcBinarySerializer.Serialize(original, options);
                    var offset = 0;
                    var chunkSize = (seed % 5) + 1;
                    while (offset < binary.Length)
                    {
                        var take = Math.Min(chunkSize, binary.Length - offset);
                        reader.Write(binary.AsSpan(offset, take));
                        offset += take;
                        await Task.Yield();
                    }
                }
                finally
                {
                    reader.Complete();
                }
            });

            await Task.WhenAll(serializeTask, deserializeTask);

            var result = deserializeTask.Result;
            Assert.IsNotNull(result);
            AssertPayloadEquals(original, result);
        });

        await Task.WhenAll(pipelines);
    }

    private static TestParentWithDateTimeItemCollection CreatePayload(int itemCount)
    {
        var now = DateTime.UtcNow;
        var items = new List<TestEntityWithDateTimeAndInt>(itemCount);

        for (var i = 0; i < itemCount; i++)
        {
            items.Add(new TestEntityWithDateTimeAndInt
            {
                Id = i + 1,
                IntValue = i * 3,
                Created = now.AddMinutes(-i),
                Modified = now.AddMinutes(i),
                StatusCode = i % 4,
                Name = $"item-{i}"
            });
        }

        return new TestParentWithDateTimeItemCollection
        {
            Id = 11,
            Name = "pipe-parallel-test",
            Created = now,
            Items = items
        };
    }

    private static void AssertPayloadEquals(TestParentWithDateTimeItemCollection expected, TestParentWithDateTimeItemCollection actual)
    {
        Assert.AreEqual(expected.Id, actual.Id);
        Assert.AreEqual(expected.Name, actual.Name);
        Assert.AreEqual(expected.Created, actual.Created);

        Assert.IsNotNull(expected.Items);
        Assert.IsNotNull(actual.Items);
        Assert.AreEqual(expected.Items.Count, actual.Items.Count);

        for (var i = 0; i < expected.Items.Count; i++)
        {
            var e = expected.Items[i];
            var a = actual.Items[i];

            Assert.AreEqual(e.Id, a.Id);
            Assert.AreEqual(e.IntValue, a.IntValue);
            Assert.AreEqual(e.Created, a.Created);
            Assert.AreEqual(e.Modified, a.Modified);
            Assert.AreEqual(e.StatusCode, a.StatusCode);
            Assert.AreEqual(e.Name, a.Name);
        }
    }
}