using System;
using System.Threading;
using System.Threading.Tasks;
using GB5Shared.DTO.Framework.Login;
using Microsoft.Extensions.Caching.Memory;

namespace GB5Shared.GOP.Qualifier
{
    // ============================================================
    // IEntityCodeResolver — bridges BaseEntityAppService's numeric
    // EntityId (EntityConstant.*) to the string EntityCode the GOP
    // qualifier engine binds against (MQUALIFIERENTITY.ENTITYCODE).
    //
    // MENTITY is global framework metadata (no TENANTID column/filter
    // anywhere else in the codebase) — safe to cache indefinitely per
    // process; nothing in the ExecuteSaveAsync pipeline writes to it.
    // ============================================================
    public interface IEntityCodeResolver
    {
        Task<string?> ResolveAsync(int entityId, LoginDTO loginDTO, CancellationToken ct = default);
    }

    public class EntityCodeResolver : IEntityCodeResolver
    {
        private static readonly TimeSpan CacheTtl = TimeSpan.FromHours(6);

        private readonly IQualifierDAL _Dal;
        private readonly IMemoryCache  _Cache;

        public EntityCodeResolver(IQualifierDAL dal, IMemoryCache cache)
        {
            _Dal   = dal;
            _Cache = cache;
        }

        public async Task<string?> ResolveAsync(int entityId, LoginDTO loginDTO, CancellationToken ct = default)
        {
            var cacheKey = $"EntityCode:{entityId}";

            if (_Cache.TryGetValue(cacheKey, out string? cached))
                return cached;

            var entityCode = await _Dal.GetEntityCodeById(entityId, loginDTO, ct);
            _Cache.Set(cacheKey, entityCode, CacheTtl);
            return entityCode;
        }
    }
}