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

namespace WIDESEAWCS_RedisService.Leaderboard
{
    public class RedisLeaderboardService : ILeaderboardService
    {
        private readonly IRedisConnectionManager _connectionManager;
        private readonly RedisOptions _options;
        private readonly ILogger<RedisLeaderboardService> _logger;

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

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

        public bool AddOrUpdate(string boardName, string member, double score)
        {
            return _connectionManager.GetDatabase().SortedSetAdd(BuildKey(boardName), member, score);
        }

        public double IncrementScore(string boardName, string member, double increment)
        {
            return _connectionManager.GetDatabase().SortedSetIncrement(BuildKey(boardName), member, increment);
        }

        public long? GetRank(string boardName, string member)
        {
            return _connectionManager.GetDatabase().SortedSetRank(BuildKey(boardName), member, Order.Descending);
        }

        public double? GetScore(string boardName, string member)
        {
            return _connectionManager.GetDatabase().SortedSetScore(BuildKey(boardName), member);
        }

        public List<LeaderboardEntry> GetTopN(string boardName, int count)
        {
            return GetRange(boardName, 0, count - 1);
        }

        public List<LeaderboardEntry> GetRange(string boardName, long start, long stop)
        {
            var entries = _connectionManager.GetDatabase()
                .SortedSetRangeByRankWithScores(BuildKey(boardName), start, stop, Order.Descending);

            return entries.Select((e, i) => new LeaderboardEntry
            {
                Member = e.Element.ToString(),
                Score = e.Score,
                Rank = start + i
            }).ToList();
        }

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

        public long GetCount(string boardName)
        {
            return _connectionManager.GetDatabase().SortedSetLength(BuildKey(boardName));
        }
    }
}