using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using StackExchange.Redis;
using WIDESEAWCS_RedisService.Connection;
using WIDESEAWCS_RedisService.Options;

namespace WIDESEAWCS_RedisService.DelayQueue
{
    public class RedisDelayQueueService : IDelayQueueService
    {
        private readonly IRedisConnectionManager _connectionManager;
        private readonly RedisOptions _options;
        private readonly ILogger<RedisDelayQueueService> _logger;

        public RedisDelayQueueService(
            IRedisConnectionManager connectionManager,
            IOptions<RedisOptions> options,
            ILogger<RedisDelayQueueService> logger)
        {
            _connectionManager = connectionManager;
            _options = options.Value;
            _logger = logger;
        }

        private string BuildKey(string key) => $"{_options.KeyPrefix}delay:{key}";

        public bool Enqueue(string queueName, string message, TimeSpan delay)
        {
            var score = DateTimeOffset.UtcNow.Add(delay).ToUnixTimeMilliseconds();
            return _connectionManager.GetDatabase().SortedSetAdd(BuildKey(queueName), message, score);
        }

        public List<string> DequeueDue(string queueName, int count = 10)
        {
            var db = _connectionManager.GetDatabase();
            var fullKey = BuildKey(queueName);
            var now = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds();

            var entries = db.SortedSetRangeByScore(fullKey, 0, now, take: count);
            var result = new List<string>();

            foreach (var entry in entries)
            {
                if (db.SortedSetRemove(fullKey, entry))
                    result.Add(entry.ToString());
            }
            return result;
        }

        public bool Remove(string queueName, string message)
        {
            return _connectionManager.GetDatabase().SortedSetRemove(BuildKey(queueName), message);
        }

        public long GetQueueLength(string queueName)
        {
            return _connectionManager.GetDatabase().SortedSetLength(BuildKey(queueName));
        }
    }
}