using ErrorOr;
using Microsoft.EntityFrameworkCore;
using Musify.Application.Albums;
using Musify.Application.Tests.TestSupport;
using Musify.Domain.Entities;
using Xunit;

namespace Musify.Application.Tests.Albums;

public sealed class RemoveTrackFromAlbumCommandHandlerTests : HandlerTestBase
{
    private RemoveTrackFromAlbumCommandHandler CreateHandler() =>
        new(Database, NoOpLogger<RemoveTrackFromAlbumCommandHandler>());

    [Fact]
    public async Task Handle_TrackInAlbum_RemovesItAndRenumbersTheRest()
    {
        var owner = TestEntities.User();
        var album = TestEntities.Album(owner.Id);
        var first = TestEntities.Track(owner, "First");
        var second = TestEntities.Track(owner, "Second");
        var third = TestEntities.Track(owner, "Third");
        await SeedAsync(
            owner, album, first, second, third,
            new AlbumHasTrack { AlbumId = album.Id, TrackId = first.Id, TrackNumber = 1 },
            new AlbumHasTrack { AlbumId = album.Id, TrackId = second.Id, TrackNumber = 2 },
            new AlbumHasTrack { AlbumId = album.Id, TrackId = third.Id, TrackNumber = 3 });

        var result = await CreateHandler().Handle(new RemoveTrackFromAlbumCommand(owner.Id, album.Id, second.Id), TestContext.Current.CancellationToken);

        Assert.False(result.IsError);
        var remaining = await Database.AlbumHasTracks
            .Where(link => link.AlbumId == album.Id)
            .OrderBy(link => link.TrackNumber)
            .ToListAsync(TestContext.Current.CancellationToken);
        Assert.Equal([first.Id, third.Id], remaining.Select(link => link.TrackId));
        Assert.Equal([1, 2], remaining.Select(link => link.TrackNumber));
    }

    [Fact]
    public async Task Handle_AlbumMissing_ReturnsNotFound()
    {
        var result = await CreateHandler().Handle(new RemoveTrackFromAlbumCommand(1, Guid.NewGuid(), Guid.NewGuid()), TestContext.Current.CancellationToken);

        Assert.Equal(ErrorType.NotFound, result.FirstError.Type);
    }

    [Fact]
    public async Task Handle_NotOwner_ReturnsForbidden()
    {
        var owner = TestEntities.User(1, "owner");
        var stranger = TestEntities.User(2, "stranger");
        var album = TestEntities.Album(owner.Id);
        await SeedAsync(owner, stranger, album);

        var result = await CreateHandler().Handle(new RemoveTrackFromAlbumCommand(stranger.Id, album.Id, Guid.NewGuid()), TestContext.Current.CancellationToken);

        Assert.Equal(ErrorType.Forbidden, result.FirstError.Type);
    }

    [Fact]
    public async Task Handle_TrackNotInAlbum_ReturnsNotFound()
    {
        var owner = TestEntities.User();
        var album = TestEntities.Album(owner.Id);
        await SeedAsync(owner, album);

        var result = await CreateHandler().Handle(new RemoveTrackFromAlbumCommand(owner.Id, album.Id, Guid.NewGuid()), TestContext.Current.CancellationToken);

        Assert.Equal(ErrorType.NotFound, result.FirstError.Type);
    }
}