using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MP.Data.Services
{
    /// <summary>
    /// Gestore statistiche esecuzione processi x analisi timing
    /// </summary>
    public class ExecStatsCollector : IDisposable
    {
        #region Public Methods

        public void Dispose()
        {
            TrackData.Clear();
        }

        /// <summary>
        /// restituisce una stringa da poter emettere in log con il summary degli eventi tracciati ed eventuale reset...
        /// </summary>
        /// <param name="CallName"></param>
        /// <param name="resetCount"></param>
        /// <returns></returns>
        public string GetCallSum(string CallName, bool resetCount)
        {
            string answ = "";
            if (TrackData.ContainsKey(CallName))
            {
                var reqRec = TrackData[CallName];
                answ = $"{CallName} | {reqRec.NumCall} x {reqRec.AvgTime:N3}ms | min: {reqRec.MinTime:N3}ms | MAX: {reqRec.MaxTime:N3}ms";
                // se richiede reset --> effettuo
                if (resetCount)
                {
                    TrackData[CallName].ListMsRec = new List<double>();
                }
            }
            return answ;
        }

        /// <summary>
        /// Accumula record di tracciamento info esecuzione e restituisce numero elementi finali
        /// </summary>
        /// <param name="CallName">nome chiamata da registrare</param>
        /// <param name="msDuration">Durata in ms</param>
        /// <returns></returns>
        public int RecordCall(string CallName, double msDuration)
        {
            if (TrackData.ContainsKey(CallName))
            {
                TrackData[CallName].ListMsRec.Add(msDuration);
            }
            else
            {
                TrackData.Add(CallName, new RecordData() { ListMsRec = new List<double>() { msDuration } });
            }
            return TrackData[CallName].NumCall;
        }

        #endregion Public Methods

        #region Public Classes

        /// <summary>
        /// Record atomico informazioni x un dato task tracciato
        /// </summary>
        public class RecordData
        {
            #region Public Properties

            /// <summary>
            /// Tempo medio
            /// </summary>
            public double AvgTime
            {
                get => ListMsRec.Sum(x => x) / (NumCall > 0 ? NumCall : 1);
            }

            /// <summary>
            /// Lista registrazioni di tempi esecuzione in ms
            /// </summary>
            public List<double> ListMsRec { get; set; } = new List<double>();

            /// <summary>
            /// Tempo Massimo
            /// </summary>
            public double MaxTime
            {
                get => ListMsRec.OrderByDescending(x => x).FirstOrDefault();
            }

            /// <summary>
            /// Tempo minimo
            /// </summary>
            public double MinTime
            {
                get => ListMsRec.OrderBy(x => x).FirstOrDefault();
            }

            /// <summary>
            /// numero registrazioni disponibili
            /// </summary>
            public int NumCall
            {
                get => ListMsRec.Count();
            }

            #endregion Public Properties
        }

        #endregion Public Classes

        #region Private Fields

        /// <summary>
        /// Dizionario di dati statistici accumulati
        /// </summary>
        private Dictionary<string, RecordData> TrackData = new Dictionary<string, RecordData>();

        #endregion Private Fields
    }
}