using Microsoft.EntityFrameworkCore;
using SVSim.Database;
using SVSim.Database.Enums;
using SVSim.Database.Models;

namespace SVSim.EmulatedEntrypoint.Services;

public class DbCardPoolProvider : ICardPoolProvider
{
    private readonly SVSimDbContext _db;
    public DbCardPoolProvider(SVSimDbContext db) { _db = db; }

    public IReadOnlyList<ShadowverseCardEntry> GetPool(PackConfigEntry pack)
    {
        switch (pack.PackCategory)
        {
            case PackCategory.None:
            case PackCategory.LegendCardPack:
                // Standard pack — pool comes from the card set whose id equals base_pack_id.
                return _db.CardSets
                    .Include(s => s.Cards)
                    .Where(s => s.Id == pack.BasePackId)
                    .SelectMany(s => s.Cards)
                    .ToList();

            case PackCategory.SpecialCardPack:
            case PackCategory.LimitedSpecialCardPack:
                // Legendary-special packs pull from all rotation sets. The slot-8 forced-Legendary
                // rule in PackOpenService delivers the "at least one legendary" promise.
                return _db.CardSets
                    .Where(s => s.IsInRotation)
                    .Include(s => s.Cards)
                    .SelectMany(s => s.Cards)
                    .Distinct()
                    .ToList();

            default:
                // Skin / starter / leader-skin packs aren't drawn in v1 — controller rejects earlier.
                return Array.Empty<ShadowverseCardEntry>();
        }
    }
}