using System.Collections.Generic;
using System.Threading.Tasks;
using LaDOSE.Entity;

namespace LaDOSE.Business.Interface
{
    public interface IStatisticsService
    {
        /// <summary>
        /// Aggregate the persisted sets of the given Events into per-player records,
        /// head-to-head records and a coverage report.
        /// A null or empty id list yields a well-formed, zeroed <see cref="MatchStats"/>.
        /// </summary>
        Task<MatchStats> GetMatchStats(List<int> eventIds);

        /// <summary>
        /// The players a versus lookup can say something about: those with at least one
        /// set in a bracket whose game is known, by display name.
        /// </summary>
        Task<List<PlayerOption>> GetVersusPlayers();

        /// <summary>
        /// Every recorded meeting between two players, all events, broken down per game.
        /// Sets whose bracket has no game are excluded and only counted in
        /// <see cref="PlayerVersus.UnknownGameSets"/>.
        /// Missing, equal or unknown ids yield a well-formed empty <see cref="PlayerVersus"/>.
        /// </summary>
        Task<PlayerVersus> GetVersus(int playerAId, int playerBId);
    }
}