using System.Text.Json;
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 TokenCacheService : ITokenCacheService
{
    private readonly RedisConnection _redis;
    private readonly RedisSettings _settings;
    private readonly ILogger<TokenCacheService> _logger;

    private static readonly TimeSpan CacheTtl = TimeSpan.FromHours(1);

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

    public async Task<CachedDeviceInfo?> GetDeviceInfoAsync(long serviceId, long deviceId)
    {
        try
        {
            var db = await _redis.GetDatabaseAsync();
            var value = await db.StringGetAsync(BuildKey(serviceId, deviceId));

            if (value.IsNullOrEmpty)
                return null;

            return JsonSerializer.Deserialize<CachedDeviceInfo>(value!);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "토큰 캐시 조회 실패: serviceId={ServiceId}, deviceId={DeviceId}",
                serviceId, deviceId);
            return null;
        }
    }

    public async Task SetDeviceInfoAsync(long serviceId, long deviceId, CachedDeviceInfo info)
    {
        try
        {
            var db = await _redis.GetDatabaseAsync();
            var json = JsonSerializer.Serialize(info);
            await db.StringSetAsync(BuildKey(serviceId, deviceId), json, CacheTtl);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "토큰 캐시 저장 실패: serviceId={ServiceId}, deviceId={DeviceId}",
                serviceId, deviceId);
        }
    }

    public async Task InvalidateAsync(long serviceId, long deviceId)
    {
        try
        {
            var db = await _redis.GetDatabaseAsync();
            await db.KeyDeleteAsync(BuildKey(serviceId, deviceId));
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "토큰 캐시 무효화 실패: serviceId={ServiceId}, deviceId={DeviceId}",
                serviceId, deviceId);
        }
    }

    public async Task InvalidateByServiceAsync(long serviceId)
    {
        try
        {
            var db = await _redis.GetDatabaseAsync();
            var server = _redis.GetServer();
            if (server == null) return;

            var pattern = $"{_settings.InstanceName}device:token:{serviceId}:*";
            var keys = server.Keys(pattern: pattern).ToArray();

            if (keys.Length > 0)
                await db.KeyDeleteAsync(keys);

            _logger.LogInformation("서비스 토큰 캐시 전체 무효화: serviceId={ServiceId}, 삭제={Count}건",
                serviceId, keys.Length);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "서비스 토큰 캐시 전체 무효화 실패: serviceId={ServiceId}", serviceId);
        }
    }

    private string BuildKey(long serviceId, long deviceId) =>
        $"{_settings.InstanceName}device:token:{serviceId}:{deviceId}";
}