using Entity;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata.Internal;
using Shared;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Contextlib
{
    public class DbFavoriteManager : IFavoriteService<Quote>
    {
        private WTFContext _context;
        private GenericRepository<Quote> _repo;

        public DbFavoriteManager(WTFContext context)
        {
            _context = context ?? throw new ArgumentNullException(nameof(context), "Database context cannot be null.");
            _repo = new GenericRepository<Quote>(context);
        }

        public async Task AddFavorite(int quoteid, int userId)
        {
            var quote = await _context.quotes //  collection des commentaires est chargée
                .Include(q => q.Favorite)
                .FirstOrDefaultAsync(q => q.Id == quoteid);

            var user = await _context.users //  collection des commentaires est chargée
                .Include(u => u.Favorite)
                .FirstOrDefaultAsync(q => q.Id == userId);

            if (quote == null && user == null)
            {
                throw new ArgumentException("Quote or User not exist", nameof(quoteid));
            }
            

            var fav = new Favorite
            {
                // Lien entre le favorite et la citation
                Quote = quote,
                IdQuote = quoteid,
                // Lien entre le favorite et le user
                Users = user,
                IdUsers = userId,
            };

            if (fav != null)
            {
                // Ajout favorite à la collection des favorites de la citation
                quote.Favorite.Add(user);

                // Ajout favorite à la collection des favorites de la citation
                user.Favorite.Add(quote);
            }
            _context.Add(fav);
            await _context.SaveChangesAsync();
        }


        public async Task RemoveAllFavoriteForQuote(int quoteId)
        {
            var fav = _context.favorites.Where(item => item.IdQuote == quoteId).ToList();

            if (fav == null) throw new KeyNotFoundException();

            foreach (var item in fav)
            {
                _context.favorites.Remove(item);
            }

            await _context.SaveChangesAsync();
        }

        public async Task RemoveAllFavoriteForUser(int userId)
        {
            var fav = _context.favorites.Where(item =>  item.IdUsers == userId).ToList();

            if (fav == null) throw new KeyNotFoundException();

            foreach (var item in fav)
            {
                _context.favorites.Remove(item);
            }

            await _context.SaveChangesAsync();
        }

        public async Task RemoveFavorite(int quoteid, int userId)
        {
            var fav = await _context.favorites.Where(item=>item.IdQuote==quoteid && item.IdUsers==userId).FirstAsync();

            if (fav == null) throw new KeyNotFoundException();

            _context.favorites.Remove(fav);

            await _context.SaveChangesAsync();
        }

        public async Task<Quote?> GetFavorite(int userId, int idQuote)
        {
            return await _context.quotes.Where( item => item.Id == idQuote && item.Favorite.Any(u => u.Id == userId) )
                                .Include(q => q.Source).Include(q => q.Character).ThenInclude(c => c.Images).Include(q=>q.Favorite)
                                .FirstOrDefaultAsync();
        }

        public async Task<PaginationResult<Quote>> GetFavoriteByIdUser(int userId, int index, int count)
        {
            List<Quote> fav = await _context.quotes.Where(item => item.Favorite.Any(u => u.Id == userId))
                                .Include(q => q.Source).Include(q => q.Character).ThenInclude(c => c.Images).Include(q => q.Favorite)
                                .Skip(index * count).Take(count).ToListAsync();
            return new PaginationResult<Quote>(fav.Count,index,count,fav);
        }
    }
}