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

namespace WIDESEAWCS_RedisService.PubSub
{
    public class RedisMessageQueueService : IMessageQueueService
    {
        private readonly IRedisConnectionManager _connectionManager;
        private readonly RedisOptions _options;
        private readonly ILogger<RedisMessageQueueService> _logger;

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

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

        public long Publish(string channel, string message)
        {
            var sub = _connectionManager.GetSubscriber();
            return sub.Publish(RedisChannel.Literal($"{_options.KeyPrefix}{channel}"), message);
        }

        public void Subscribe(string channel, Action<string, string> handler)
        {
            var sub = _connectionManager.GetSubscriber();
            sub.Subscribe(RedisChannel.Literal($"{_options.KeyPrefix}{channel}"), (ch, msg) =>
            {
                handler(ch!, msg!);
            });
        }

        public void Unsubscribe(string channel)
        {
            var sub = _connectionManager.GetSubscriber();
            sub.Unsubscribe(RedisChannel.Literal($"{_options.KeyPrefix}{channel}"));
        }

        public long Enqueue(string queueName, string message)
        {
            return _connectionManager.GetDatabase().ListLeftPush(BuildKey(queueName), message);
        }

        public string? Dequeue(string queueName, TimeSpan? timeout = null)
        {
            var val = _connectionManager.GetDatabase().ListRightPop(BuildKey(queueName));
            return val.IsNullOrEmpty ? null : val.ToString();
        }

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