using System;
using System.Linq;
using Domain;

namespace Application
{
  /// <summary>
  /// Service applicatif permettant la gestion des liens de la plateforme.
  /// </summary>
  public class LinkService
  {
    private readonly ILinkRepository _linkRepository;
    private readonly IData _data;

    public LinkService(ILinkRepository linkRepository, IData data)
    {
      _linkRepository = linkRepository;
      _data = data;
    }

    /// <summary>
    /// Publie un nouveau lien sur la plateforme.
    /// </summary>
    /// <param name="cmd"></param>
    /// <returns></returns>
    public Guid PublishLink(PublishLinkCommand cmd)
    {
      var link = new Link(cmd.Url);

      _linkRepository.Add(link);

      return link.Id;
    }

    /// <summary>
    /// Récupère tous les liens publiés jusqu'à présent.
    /// </summary>
    /// <returns></returns>
    public LinkDTO[] GetAllLinks()
    {
      // return (from link in _data.Links
      //         orderby link.CreatedAt descending
      //         select new LinkDTO
      //         {
      //           Id = link.Id,
      //           Url = link.Url,
      //           CreatedAt = link.CreatedAt,
      //           UpvotesCount = 2,
      //           DownvotesCount = 4,
      //           CommentsCount = 54,
      //         }).ToArray();

      return LinksDTO().ToArray();
    }

    public LinkDTO GetLinkById(Guid id)
    {
      return LinksDTO().Single(link => link.Id == id);
    }

    private IQueryable<LinkDTO> LinksDTO()
    {
      return _data.Links
        .Select(link => new LinkDTO
        {
          Id = link.Id,
          Url = link.Url,
          CreatedAt = link.CreatedAt,
          UpvotesCount = 2,
          DownvotesCount = 4,
          CommentsCount = 54,
        })
        // .Where(linkDto => linkDto.UpvotesCount > 5)
        .OrderByDescending(linkDto => linkDto.CreatedAt);
    }
  }
}