using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using ErsatzTV.Core.Interfaces.Repositories;
using LanguageExt;
using MediatR;
using static ErsatzTV.Application.MediaCards.Mapper;
using static LanguageExt.Prelude;

namespace ErsatzTV.Application.MediaCards.Queries
{
    public class GetMusicVideoCardsHandler : IRequestHandler<GetMusicVideoCards, MusicVideoCardResultsViewModel>
    {
        private readonly IMusicVideoRepository _musicVideoRepository;

        public GetMusicVideoCardsHandler(IMusicVideoRepository musicVideoRepository) =>
            _musicVideoRepository = musicVideoRepository;

        public async Task<MusicVideoCardResultsViewModel> Handle(
            GetMusicVideoCards request,
            CancellationToken cancellationToken)
        {
            int count = await _musicVideoRepository.GetMusicVideoCount(request.ArtistId);

            List<MusicVideoCardViewModel> results = await _musicVideoRepository
                .GetPagedMusicVideos(request.ArtistId, request.PageNumber, request.PageSize)
                .Map(list => list.Map(ProjectToViewModel).ToList());

            return new MusicVideoCardResultsViewModel(count, results, None);
        }
    }
}