using Microsoft.Extensions.Caching.Distributed;
using Microsoft.Extensions.Caching.Memory;
using MP.MONO.Core.DTO;
using MP.MONO.Data;
using MP.MONO.Data.Controllers;
using Newtonsoft.Json;
using NLog;
using StackExchange.Redis;
using System.Diagnostics;
using System.Text;
using StackExchange.Redis;

namespace MP.MONO.UI.Data
{
    public class CurrentDataService : IDisposable
    {
        #region Private Fields

        private static IConfiguration _configuration;
        private static ILogger<CurrentDataService> _logger;
        private static NLog.Logger Log = LogManager.GetCurrentClassLogger();
        private readonly IDistributedCache distributedCache;
        /// <summary>
        /// Oggetto per connessione a REDIS
        /// </summary>
        private ConnectionMultiplexer redisConn = null!;
        //ISubscriber sub = redis.GetSubscriber();
        /// <summary>
        /// Oggetto DB redis da impiegare x chiamate R/W
        /// </summary>
        private IDatabase redisDb = null!;

        /// <summary>
        /// Durata assoluta massima della cache IN SECONDI
        /// </summary>
        private int chAbsExp = 60 * 5;

        /// <summary>
        /// Durata della cache IN SECONDI in modalità inattiva (non acceduta) prima di venire rimossa
        /// NON estende oltre il tempo massimo di validità della cache (chAbsExp)
        /// </summary>
        private int chSliExp = 60 * 1;

        #endregion Private Fields

        #region Public Fields

        /// <summary>
        /// Controller dati da DB
        /// </summary>
        public static MpDbController dbController;
        /// <summary>
        /// Controller dati simulati
        /// </summary>
        public static SimController simGen;

        #endregion Public Fields


        public MessagePipe alarmPipe { get; set; } = null!;
        public MessagePipe parametersPipe { get; set; } = null!;
        public MessagePipe statusPipe { get; set; } = null!;

        #region Public Constructors

        public CurrentDataService(IConfiguration configuration, ILogger<CurrentDataService> logger, IDistributedCache distributedCache, IConnectionMultiplexer redisConn)
        {
            _logger = logger;
            _configuration = configuration;

            // setup compoenti REDIS
            this.redisConn = ConnectionMultiplexer.Connect(_configuration.GetConnectionString("Redis"));
            this.redisDb = this.redisConn.GetDatabase();
            // setup canali pub/sub
            alarmPipe = new MessagePipe(redisConn, "allarms");
            parametersPipe = new MessagePipe(redisConn, "parameters");
            statusPipe = new MessagePipe(redisConn, "status");

            // conf cache
            this.distributedCache = distributedCache;

            // conf DB
            string connStr = _configuration.GetConnectionString("MP.MONO.Data");
            if (string.IsNullOrEmpty(connStr))
            {
                _logger.LogError("ConnString empty!");
            }
            else
            {
                dbController = new MpDbController(configuration);
                _logger.LogInformation("DbController OK");
            }
            simGen = new SimController();
        }

        #endregion Public Constructors

        #region Protected Properties

#if false
        protected Dictionary<string, string>? ParametersList { get; set; } = new Dictionary<string, string>(); 
#endif

        #endregion Protected Properties

        #region Private Methods

        /// <summary>
        /// Hash Redis contenente i dati MP di una specifico TYPE (es StatusMacchina, StateMachineIngressi, ...)
        /// </summary>
        /// <param name="dataType"></param>
        /// <returns></returns>
        private static string mHash(string dataType)
        {
            return $"MAPO-MONO:{dataType}";
        }

        private DistributedCacheEntryOptions cacheOpt(bool fastCache)
        {
            var numSecAbsExp = fastCache ? chAbsExp : chAbsExp * 10;
            var numSecSliExp = fastCache ? chSliExp : chSliExp * 10;
            return new DistributedCacheEntryOptions().SetAbsoluteExpiration(DateTime.Now.AddSeconds(numSecAbsExp)).SetSlidingExpiration(TimeSpan.FromSeconds(numSecSliExp));
        }

        #endregion Private Methods

        #region Public Methods

        public void Dispose()
        {
            // Clear database controller
            dbController.Dispose();
        }

#if false
        public async Task<Dictionary<string, string>> GetCurrentParameters()
        {
            ParametersList = new Dictionary<string, string>();
            string cacheKey = mHash("Machine:Parameters:Current");
            string rawData = await redisDb.StringGetAsync(cacheKey);
            if (!string.IsNullOrEmpty(rawData))
            {
                ParametersList = JsonConvert.DeserializeObject<Dictionary<string, string>>(rawData);
            }
            else
            {
                ParametersList = simGen.GetCurrentParameters();
                rawData = JsonConvert.SerializeObject(ParametersList);
                await redisDb.StringSetAsync(cacheKey, rawData);
            }
            return ParametersList;
        } 
#endif

        public async Task<List<DisplayDataDTO>> MachineDisplay()
        {
            List<DisplayDataDTO>? dbResult = new List<DisplayDataDTO>();
            string cacheKey = mHash("Machine:Parameters:Current");
            string rawData = await redisDb.StringGetAsync(cacheKey);
            if (!string.IsNullOrEmpty(rawData))
            {
                dbResult = JsonConvert.DeserializeObject<List<DisplayDataDTO>>(rawData);
            }
#if false
            else
            {
                dbResult = simGen.MachineGetParameters();
                rawData = JsonConvert.SerializeObject(dbResult);
                await redisDb.StringSetAsync(cacheKey, rawData);
            } 
#endif
            if (dbResult == null)
            {
                dbResult = new List<DisplayDataDTO>();
            }
#if false

            string rawData;
            var redisDataList = await distributedCache.GetAsync(cacheKey);
            if (redisDataList != null)
            {
                rawData = Encoding.UTF8.GetString(redisDataList);
                dbResult = JsonConvert.DeserializeObject<List<DisplayDataDTO>>(rawData);
            }
            else
            {
                Stopwatch stopWatch = new Stopwatch();
                stopWatch.Start();
                dbResult = dbController.MachineGetDisplay();
                rawData = JsonConvert.SerializeObject(dbResult);
                redisDataList = Encoding.UTF8.GetBytes(rawData);
                // tolgo salvataggio x sim meglio
                //await distributedCache.SetAsync(cacheKey, redisDataList, cacheOpt(true));
                stopWatch.Stop();
                TimeSpan ts = stopWatch.Elapsed;
                Log.Trace($"Effettuata lettura da DB + caching per MachineDisplay: {ts.TotalMilliseconds} ms");
            }
            if (dbResult == null)
            {
                dbResult = new List<DisplayDataDTO>();
            } 
#endif
            return await Task.FromResult(dbResult);
        }

        public async Task<ProductionDTO> MachineProd()
        {
            ProductionDTO? dbResult = new ProductionDTO();
            string cacheKey = mHash("DATA:Machine:Prod");
            string rawData;
            var redisDataList = await distributedCache.GetAsync(cacheKey);
            if (redisDataList != null)
            {
                rawData = Encoding.UTF8.GetString(redisDataList);
                dbResult = JsonConvert.DeserializeObject<ProductionDTO>(rawData);
            }
            else
            {
                Stopwatch stopWatch = new Stopwatch();
                stopWatch.Start();
                dbResult = dbController.MachineGetProd();
                rawData = JsonConvert.SerializeObject(dbResult);
                redisDataList = Encoding.UTF8.GetBytes(rawData);
                // tolgo salvataggio x sim meglio
                //await distributedCache.SetAsync(cacheKey, redisDataList, cacheOpt(true));
                stopWatch.Stop();
                TimeSpan ts = stopWatch.Elapsed;
                Log.Trace($"Effettuata lettura da DB + caching per MachineProd: {ts.TotalMilliseconds} ms");
            }
            if (dbResult == null)
            {
                dbResult = new ProductionDTO();
            }
            return await Task.FromResult(dbResult);
        }

        public async Task<MachineDTO> MachineStatus()
        {
            MachineDTO? dbResult = new MachineDTO();
            string cacheKey = mHash("Machine:Status:Current");
            string rawData = await redisDb.StringGetAsync(cacheKey);
            if (!string.IsNullOrEmpty(rawData))
            {
                dbResult = JsonConvert.DeserializeObject<MachineDTO>(rawData);
            }
#if false
            else
            {
                dbResult = simGen.MachineGetStatus();
                rawData = JsonConvert.SerializeObject(dbResult);
                redisDb.StringSetAsync(cacheKey, rawData);
            } 
#endif
            if (dbResult == null)
            {
                dbResult = new MachineDTO();
            }
            return await Task.FromResult(dbResult);
        }

        #endregion Public Methods
    }
}