using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using SPMS.Application.Interfaces;
using SPMS.Application.Settings;
using StackExchange.Redis;

namespace SPMS.Infrastructure.Caching;

public class DuplicateChecker : IDuplicateChecker
{
    private readonly RedisConnection _redis;
    private readonly RedisSettings _settings;
    private readonly ILogger<DuplicateChecker> _logger;

    public DuplicateChecker(
        RedisConnection redis,
        IOptions<RedisSettings> settings,
        ILogger<DuplicateChecker> logger)
    {
        _redis = redis;
        _settings = settings.Value;
        _logger = logger;
    }

    public async Task<bool> IsDuplicateAsync(string requestId, CancellationToken cancellationToken = default)
    {
        var key = $"{_settings.InstanceName}duplicate:{requestId}";
        var ttl = TimeSpan.FromHours(_settings.DuplicateTtlHours);

        try
        {
            var db = await _redis.GetDatabaseAsync();
            var wasSet = await db.StringSetAsync(key, "1", ttl, When.NotExists);

            if (!wasSet)
            {
                _logger.LogWarning("중복 메시지 감지: requestId={RequestId}", requestId);
                return true;
            }

            return false;
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Redis 중복 체크 실패: requestId={RequestId} — 중복 아닌 것으로 처리", requestId);
            return false;
        }
    }
}