using ErsatzTV.Application.Channels;
using ErsatzTV.Core;
using ErsatzTV.Core.Domain;
using ErsatzTV.Core.Graphics;
using ErsatzTV.FFmpeg.State;
using ErsatzTV.Infrastructure.Data;
using ErsatzTV.Tests.Support;
using LanguageExt;
using Microsoft.EntityFrameworkCore;
using NUnit.Framework;
using Shouldly;

namespace ErsatzTV.Tests.Application.Channels;

/// <summary>
/// #732: the On Now / Next overlay is a default rather than an opt-in, so a channel created after
/// that decision gets the built-in element without the operator toggling anything.
/// </summary>
[TestFixture]
public class CreateChannelDefaultGraphicsElementTests : ChannelHandlerTestBase
{
    private CreateChannelHandler MakeHandler() => new(Worker, Db.Factory, SearchTargets, RemoteLogoCacher);

    private async Task<int> SeedBuiltInElement()
    {
        await using TvContext context = Db.CreateContext();
        var element = new GraphicsElement
        {
            Path = $"/templates/text/{GraphicsElementDefaults.OnNowNextFileName}",
            Kind = GraphicsElementKind.Text
        };

        context.GraphicsElements.Add(element);
        await context.SaveChangesAsync();
        return element.Id;
    }

    private async Task<List<int>> AttachedElementIds(int channelId)
    {
        await using TvContext context = Db.CreateContext();
        Channel reloaded = await context.Channels
            .Include(c => c.ChannelGraphicsElements)
            .SingleAsync(c => c.Id == channelId);

        return reloaded.ChannelGraphicsElements.Select(x => x.GraphicsElementId).ToList();
    }

    [Test]
    public async Task Attaches_The_Built_In_Element_To_A_New_Channel()
    {
        await SeedFFmpegProfile();
        int elementId = await SeedBuiltInElement();

        Either<BaseError, CreateChannelResult> result =
            await MakeHandler().Handle(MakeCreate(), CancellationToken.None);

        result.IsRight.ShouldBeTrue();
        int channelId = result.RightToSeq().Head().ChannelId;

        (await AttachedElementIds(channelId)).ShouldBe([elementId]);
    }

    [Test]
    public async Task Leaves_An_Hls_Direct_Channel_Alone_Because_Nothing_Can_Render_There()
    {
        await SeedFFmpegProfile();
        await SeedBuiltInElement();

        Either<BaseError, CreateChannelResult> result = await MakeHandler().Handle(
            MakeCreate(streamingMode: StreamingMode.HttpLiveStreamingDirect),
            CancellationToken.None);

        result.IsRight.ShouldBeTrue();
        int channelId = result.RightToSeq().Head().ChannelId;

        (await AttachedElementIds(channelId)).ShouldBeEmpty();
    }

    [Test]
    public async Task Creates_The_Channel_Even_When_The_Built_In_Element_Does_Not_Exist()
    {
        await SeedFFmpegProfile();

        Either<BaseError, CreateChannelResult> result =
            await MakeHandler().Handle(MakeCreate(), CancellationToken.None);

        result.IsRight.ShouldBeTrue();
        int channelId = result.RightToSeq().Head().ChannelId;

        (await AttachedElementIds(channelId)).ShouldBeEmpty();
    }
}