/*
 * QUANTCONNECT.COM - Democratizing Finance, Empowering Individuals.
 * Lean Algorithmic Trading Engine v2.0. Copyright 2014 QuantConnect Corporation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); 
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
*/

using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using Newtonsoft.Json;
using QuantConnect.Interfaces;
using QuantConnect.Lean.Engine.DataFeeds;
using QuantConnect.Lean.Engine.Setup;
using QuantConnect.Lean.Engine.TransactionHandlers;
using QuantConnect.Logging;
using QuantConnect.Orders;
using QuantConnect.Packets;
using QuantConnect.Statistics;
using QuantConnect.Util;

namespace QuantConnect.Lean.Engine.Results
{
    /// <summary>
    /// Backtesting result handler passes messages back from the Lean to the User.
    /// </summary>
    public class BacktestingResultHandler : IResultHandler
    {
        private bool _exitTriggered = false;
        private BacktestNodePacket _job;
        private int _jobDays = 0;
        private string _compileId = "";
        private string _backtestId = "";
        private DateTime _nextUpdate = new DateTime();
        private DateTime _nextS3Update = new DateTime();
        DateTime _lastUpdate = new DateTime();
        private string _debugMessage = "";
        private List<string> _log = new List<string>();
        private string _errorMessage = "";
        private IAlgorithm _algorithm;
        private ConcurrentQueue<Packet> _messages;
        private ConcurrentDictionary<string, Chart> _charts;
        private bool _isActive = true;
        private object _chartLock = new Object();
        private double _daysProcessed = 0;
        private double _lastDaysProcessed = 1;
        private bool _processingFinalPacket = false;

        //Debug variables:
        private int _debugMessageCount = 0;
        private int _debugMessageMin = 100;
        private int _debugMessageMax = 10;
        private int _debugMessageLength = 200;
        private string _debugMessagePeriod = "day";

        //Sampling Periods:
        private TimeSpan _resamplePeriod = TimeSpan.FromMinutes(4);
        private TimeSpan _notificationPeriod = TimeSpan.FromSeconds(2);

        //Processing Time:
        private DateTime _startTime;
        private DateTime _nextSample;
        private IMessagingHandler _messagingHandler;
        private IApi _api;
        private ITransactionHandler _transactionHandler;

        private const double _samples = 4000;
        private const double _minimumSamplePeriod = 4;

        /// <summary>
        /// Packeting message queue to temporarily store packets and then pull for processing.
        /// </summary>
        public ConcurrentQueue<Packet> Messages 
        {
            get
            {
                return _messages;
            }
            set 
            {
                _messages = value;
            }
        }

        /// <summary>
        /// Local object access to the algorithm for the underlying Debug and Error messaging.
        /// </summary>
        public IAlgorithm Algorithm 
        {
            get
            {
                return _algorithm;
            }
            set
            {
                _algorithm = value;
            }
        }

        /// <summary>
        /// Charts collection for storing the master copy of user charting data.
        /// </summary>
        public ConcurrentDictionary<string, Chart> Charts 
        {
            get
            {
                return _charts;
            }
            set
            {
                _charts = value;
            }
        }

        /// <summary>
        /// Boolean flag indicating the result hander thread is completely finished and ready to dispose.
        /// </summary>
        public bool IsActive 
        { 
            get
            {
                return _isActive;
            }
        }



        /// <summary>
        /// Sampling period for timespans between resamples of the charting equity.
        /// </summary>
        /// <remarks>Specifically critical for backtesting since with such long timeframes the sampled data can get extreme.</remarks>
        public TimeSpan ResamplePeriod
        {
            get 
            {
                return _resamplePeriod;
            }
        }

        /// <summary>
        /// How frequently the backtests push messages to the browser.
        /// </summary>
        /// <remarks>Update frequency of notification packets</remarks>
        public TimeSpan NotificationPeriod
        {
            get 
            {
                return _notificationPeriod;
            }
        }

        /// <summary>
        /// Default initializer for 
        /// </summary>
        public BacktestingResultHandler()
        {
            //Initialize Properties:
            _messages = new ConcurrentQueue<Packet>();
            _charts = new ConcurrentDictionary<string, Chart>();
            _chartLock = new Object();
            _isActive = true;

            //Notification Period for Browser Pushes:
            _notificationPeriod = TimeSpan.FromSeconds(2);
            _exitTriggered = false;

            //Set the start time for the algorithm
            _startTime = DateTime.Now;

            //Default charts:
            Charts.AddOrUpdate("Strategy Equity", new Chart("Strategy Equity", ChartType.Stacked));
            Charts["Strategy Equity"].Series.Add("Equity", new Series("Equity", SeriesType.Candle));
            Charts["Strategy Equity"].Series.Add("Daily Performance", new Series("Daily Performance", SeriesType.Bar, "%"));
        }

        /// <summary>
        /// Initialize the result handler with this result packet.
        /// </summary>
        /// <param name="job">Algorithm job packet for this result handler</param>
        /// <param name="messagingHandler">The handler responsible for communicating messages to listeners</param>
        /// <param name="api">The api instance used for handling logs</param>
        /// <param name="dataFeed"></param>
        /// <param name="setupHandler"></param>
        /// <param name="transactionHandler"></param>
        public void Initialize(AlgorithmNodePacket job, IMessagingHandler messagingHandler, IApi api, IDataFeed dataFeed, ISetupHandler setupHandler, ITransactionHandler transactionHandler)
        {
            _api = api;
            _messagingHandler = messagingHandler;
            _transactionHandler = transactionHandler;
            _job = (BacktestNodePacket)job;
            if (_job == null) throw new Exception("BacktestingResultHandler.Constructor(): Submitted Job type invalid.");
            _compileId = _job.CompileId;
            _backtestId = _job.BacktestId;

            //Get the resample period:
            var totalMinutes = (_job.PeriodFinish - _job.PeriodStart).TotalMinutes;
            var resampleMinutes = (totalMinutes < (_minimumSamplePeriod * _samples)) ? _minimumSamplePeriod : (totalMinutes / _samples); // Space out the sampling every 
            _resamplePeriod = TimeSpan.FromMinutes(resampleMinutes);
            Log.Trace("BacktestingResultHandler(): Sample Period Set: " + resampleMinutes.ToString("00.00"));
        }
        
        /// <summary>
        /// The main processing method steps through the messaging queue and processes the messages one by one.
        /// </summary>
        public void Run() 
        {
            //Initialize:
            var lastMessage = "";
            _lastDaysProcessed = 5;

            //Setup minimum result arrays:
            //SampleEquity(job.periodStart, job.startingCapital);
            //SamplePerformance(job.periodStart, 0);

            try
            {
                while (!(_exitTriggered && Messages.Count == 0))
                {
                    //While there's no work to do, go back to the algorithm:
                    if (Messages.Count == 0)
                    {
                        Thread.Sleep(50);
                    }
                    else
                    {
                        //1. Process Simple Messages in Queue
                        Packet packet;
                        if (Messages.TryDequeue(out packet))
                        {
                            switch (packet.Type)
                            {
                                //New Debug Message:
                                case PacketType.Debug:
                                    var debug = packet as DebugPacket;
                                    if (lastMessage != debug.Message)
                                    {
                                        //Log.Trace("BacktestingResultHandlerRun(): Debug Packet: " + debug.Message);
                                        _messagingHandler.DebugMessage(debug.Message, debug.ProjectId, _backtestId, _compileId);
                                        lastMessage = debug.Message;
                                    }
                                    break;

                                //Send log messages to the browser as well for live trading:
                                case PacketType.SecurityTypes:
                                    var securityPacket = packet as SecurityTypesPacket;
                                    _messagingHandler.SecurityTypes(securityPacket);
                                    break;

                                case PacketType.RuntimeError:
                                    //Log.Error("QC.AlgorithmWorker.Run(): " + packet.Message);
                                    var runtime = packet as RuntimeErrorPacket;
                                    _messagingHandler.RuntimeError(_backtestId, runtime.Message, runtime.StackTrace);
                                    break;

                                case PacketType.HandledError:
                                    var handled = packet as HandledErrorPacket;
                                    Log.Error("BacktestingResultHandler.Run(): HandledError Packet: " + handled.Message);
                                    _messagingHandler.Send(handled);
                                    break;

                                default:
                                    //Default case..
                                    _messagingHandler.Send(packet);
                                    Log.Trace("BacktestingResultHandler.Run(): Default packet type: " + packet.Type);
                                    break;
                            }
                        }
                    }

                    //2. Update the packet scanner:
                    Update();

                } // While !End.
            }
            catch (Exception err)
            {
                // unexpected error, we need to close down shop
                Log.Error(err);
                // quit the algorithm due to error
                _algorithm.RunTimeError = err;
            }

            Log.Trace("BacktestingResultHandler.Run(): Ending Thread...");
            _isActive = false;
        } // End Run();

        /// <summary>
        /// Send a backtest update to the browser taking a latest snapshot of the charting data.
        /// </summary>
        public void Update() 
        {
            try
            {
                //Sometimes don't run the update, if not ready or we're ending.
                if (Algorithm == null || Algorithm.Transactions == null || _processingFinalPacket)
                {
                    return;
                }

                if (DateTime.Now <= _nextUpdate || !(_daysProcessed > (_lastDaysProcessed + 1))) return;

                //Extract the orders since last update
                var deltaOrders = new Dictionary<int, Order>();

                try
                {
                    deltaOrders = (from order in _transactionHandler.Orders
                        where order.Value.Time.Date >= _lastUpdate && order.Value.Status == OrderStatus.Filled
                        select order).ToDictionary(t => t.Key, t => t.Value);
                }
                catch (Exception err) 
                {
                    Log.Error("BacktestingResultHandler().Update(): Transactions: " + err.Message);
                }

                //Limit length of orders we pass back dynamically to avoid flooding.
                if (deltaOrders.Count > 50) deltaOrders.Clear();

                //Reset loop variables:
                try
                {
                    _lastUpdate = Algorithm.Time.Date;
                    _lastDaysProcessed = _daysProcessed;
                    _nextUpdate = DateTime.Now.AddSeconds(0.5);
                }
                catch (Exception err) 
                {
                    Log.Error("BacktestingResultHandler.Update(): Can't update variables: " + err.Message);
                }

                var deltaCharts = new Dictionary<string, Chart>();
                lock (_chartLock)
                {
                    //Get the updates since the last chart
                    foreach (var chart in Charts.Values) 
                    {
                        deltaCharts.Add(chart.Name, chart.GetUpdates());
                    }
                }

                //Profit Loss Changes:
                var progress = Convert.ToDecimal(_daysProcessed / _jobDays);
                if (progress > 0.999m) progress = 0.999m;

                //1. Cloud Upload -> Upload the whole packet to S3  Immediately:
                var completeResult = new BacktestResult(Charts, _transactionHandler.Orders, Algorithm.Transactions.TransactionRecord, new Dictionary<string, string>(), new Dictionary<string, AlgorithmPerformance>());
                var complete = new BacktestResultPacket(_job, completeResult, progress);

                if (DateTime.Now > _nextS3Update)
                {
                    _nextS3Update = DateTime.Now.AddSeconds(30);
                    StoreResult(complete, false);
                }

                //2. Backtest Update -> Send the truncated packet to the backtester:
                var splitPackets = SplitPackets(deltaCharts, deltaOrders, progress);

                foreach (var backtestingPacket in splitPackets)
                {
                    _messagingHandler.Send(backtestingPacket);
                }
            }
            catch (Exception err) 
            {
                Log.Error("BacktestingResultHandler().Update(): " + err.Message + " >> " + err.StackTrace );
            }
        }

        /// <summary>
        /// Run over all the data and break it into smaller packets to ensure they all arrive at the terminal
        /// </summary>
        public IEnumerable<BacktestResultPacket> SplitPackets(Dictionary<string, Chart> deltaCharts, Dictionary<int, Order> deltaOrders, decimal progress)
        {
            // break the charts into groups
            var splitPackets = new List<BacktestResultPacket>();
            foreach (var chart in deltaCharts.Values)
            {
                //Don't add packet if the series is empty:
                if (chart.Series.Values.Sum(x => x.Values.Count) == 0) continue;

                splitPackets.Add(new BacktestResultPacket(_job, new BacktestResult { Charts = new Dictionary<string, Chart>()
                {
                    {chart.Name,chart}
                }  }, progress));
            }

            // Add the orders into the charting packet:
            splitPackets.Add(new BacktestResultPacket(_job, new BacktestResult { Orders = deltaOrders }, progress));

            return splitPackets;
        }

        /// <summary>
        /// Save the snapshot of the total results to storage.
        /// </summary>
        /// <param name="packet">Packet to store.</param>
        /// <param name="async">Store the packet asyncronously to speed up the thread.</param>
        /// <remarks>Async creates crashes in Mono 3.10 if the thread disappears before the upload is complete so it is disabled for now.</remarks>
        public void StoreResult(Packet packet, bool async = false)
        {
            //Initialize:
            var serialized = "";
            var key = "";

            try
            {
                lock (_chartLock)
                {
                    //1. Make sure this is the right type of packet:
                    if (packet.Type != PacketType.BacktestResult) return;

                    //2. Port to packet format:
                    var result = packet as BacktestResultPacket;

                    if (result != null)
                    {
                        //3. Get Storage Location:
                        key = "backtests/" + _job.UserId + "/" + _job.ProjectId + "/" + _job.BacktestId + ".json";

                        //4. Serialize to JSON:
                        serialized = JsonConvert.SerializeObject(result.Results);
                    }
                    else 
                    {
                        Log.Error("BacktestingResultHandler.StoreResult(): Result Null.");
                    }

                    //Upload Results Portion
                    _api.Store(serialized, key, StoragePermissions.Authenticated, async);
                }
            }
            catch (Exception err)
            {
                Log.Error("BacktestingResultHandler.StoreResult(): " + err.Message);
            }
        }

        /// <summary>
        /// Send a final analysis result back to the IDE.
        /// </summary>
        /// <param name="job">Lean AlgorithmJob task</param>
        /// <param name="orders">Collection of orders from the algorithm</param>
        /// <param name="profitLoss">Collection of time-profit values for the algorithm</param>
        /// <param name="holdings">Current holdings state for the algorithm</param>
        /// <param name="statisticsResults">Statistics information for the algorithm (empty if not finished)</param>
        /// <param name="banner">Runtime statistics banner information</param>
        public void SendFinalResult(AlgorithmNodePacket job, Dictionary<int, Order> orders, Dictionary<DateTime, decimal> profitLoss, Dictionary<string, Holding> holdings, StatisticsResults statisticsResults, Dictionary<string, string> banner)
        { 
            try 
            {
                //Convert local dictionary:
                var charts = new Dictionary<string, Chart>(Charts);
                _processingFinalPacket = true;

                //Create a result packet to send to the browser.
                BacktestResultPacket result = new BacktestResultPacket((BacktestNodePacket) job,
                    new BacktestResult(charts, orders, profitLoss, statisticsResults.Summary, statisticsResults.RollingPerformances), 1m)
                {
                    ProcessingTime = (DateTime.Now - _startTime).TotalSeconds,
                    DateFinished = DateTime.Now,
                    Progress = 1
                };

                //Place result into storage.
                StoreResult(result);

                //Truncate packet to fit within 32kb of messaging limits.
                result.Results = new BacktestResult();

                //Second, send the truncated packet:
                _messagingHandler.BacktestResult(result, finalPacket: true);

                Log.Trace("BacktestingResultHandler.SendAnalysisResult(): Processed final packet"); 
            } 
            catch (Exception err) 
            {
                Log.Error("Algorithm.Worker.SendResult(): " + err.Message);
            }
        }

        /// <summary>
        /// Set the Algorithm instance for ths result.
        /// </summary>
        /// <param name="algorithm">Algorithm we're working on.</param>
        /// <remarks>While setting the algorithm the backtest result handler.</remarks>
        public void SetAlgorithm(IAlgorithm algorithm)
        {
            _algorithm = algorithm;
            
            //Setup the sampling periods:
            _jobDays = Time.TradeableDates(Algorithm.Securities.Values, _job.PeriodStart, _job.PeriodFinish);

            //Setup Debug Messaging:
            _debugMessageMax = Convert.ToInt32(10 * _jobDays);
            //Minimum 100 messages per backtest:
            if (_debugMessageMax < _debugMessageMin) _debugMessageMax = _debugMessageMin;
            //Messaging for the log messages:
            _debugMessagePeriod = "backtest";

            //Set the security / market types.
            var types = new List<SecurityType>();
            foreach (var security in _algorithm.Securities.Values)
            {
                if (!types.Contains(security.Type)) types.Add(security.Type);
            }
            SecurityType(types);

            // we need to forward Console.Write messages to the algorithm's Debug function
            var debug = new FuncTextWriter(algorithm.Debug);
            var error = new FuncTextWriter(algorithm.Error);
            Console.SetOut(debug);
            Console.SetError(error);
        }

        /// <summary>
        /// Send a debug message back to the browser console.
        /// </summary>
        /// <param name="message">Message we'd like shown in console.</param>
        public void DebugMessage(string message) 
        {
            if (message == _debugMessage) return;
            if (message.Trim() == "") return;
            if (Messages.Count > 500) return;

            if (_debugMessageCount++ < _debugMessageMax)
            {
                if (message.Length > _debugMessageLength)
                {
                    message = message.Substring(0, 100) + "...";
                }
            }
            else
            {
                message = "Maximum " + _debugMessageMax + " messages of " + _debugMessageLength + " characters per " + _debugMessagePeriod + ". This is to avoid crashing your browser. If you'd like more please use Log() command instead.";
            }

            Messages.Enqueue(new DebugPacket(_job.ProjectId, _backtestId, _compileId, message));

            //Save last message sent:
            _log.Add(_algorithm.Time.ToString(DateFormat.UI) + " " + message);
            _debugMessage = message;
        }

        /// <summary>
        /// Send a logging message to the log list for storage.
        /// </summary>
        /// <param name="message">Message we'd in the log.</param>
        public void LogMessage(string message)
        {
            _log.Add(_algorithm.Time.ToString( DateFormat.UI ) + " " + message);
        }

        /// <summary>
        /// Send list of security asset types the algortihm uses to browser.
        /// </summary>
        public void SecurityType(List<SecurityType> types)
        {
            var packet = new SecurityTypesPacket
            {
                Types = types
            };
            Messages.Enqueue(packet);
        }

        /// <summary>
        /// Send an error message back to the browser highlighted in red with a stacktrace.
        /// </summary>
        /// <param name="message">Error message we'd like shown in console.</param>
        /// <param name="stacktrace">Stacktrace information string</param>
        public void ErrorMessage(string message, string stacktrace = "") 
        {
            if (message == _errorMessage) return;
            if (Messages.Count > 500) return;
            Messages.Enqueue(new HandledErrorPacket(_backtestId, message, stacktrace));
            _errorMessage = message;
        }

        /// <summary>
        /// Send a runtime error message back to the browser highlighted with in red 
        /// </summary>
        /// <param name="message">Error message.</param>
        /// <param name="stacktrace">Stacktrace information string</param>
        public void RuntimeError(string message, string stacktrace = "") 
        {
            PurgeQueue();
            Messages.Enqueue(new RuntimeErrorPacket(_backtestId, message, stacktrace));
            _errorMessage = message;
        }

        /// <summary>
        /// Add a sample to the chart specified by the chartName, and seriesName.
        /// </summary>
        /// <param name="chartName">String chart name to place the sample.</param>
        /// <param name="chartType">Type of chart we should create if it doesn't already exist.</param>
        /// <param name="seriesName">Series name for the chart.</param>
        /// <param name="seriesType">Series type for the chart.</param>
        /// <param name="time">Time for the sample</param>
        /// <param name="unit">Unit of the sample</param>
        /// <param name="value">Value for the chart sample.</param>
        public void Sample(string chartName, ChartType chartType, string seriesName, SeriesType seriesType, DateTime time, decimal value, string unit = "$") 
        {
            lock (_chartLock)
            {
                //Add a copy locally:
                if (!Charts.ContainsKey(chartName))
                {
                    Charts.AddOrUpdate(chartName, new Chart(chartName, chartType));
                }

                //Add the sample to our chart:
                if (!Charts[chartName].Series.ContainsKey(seriesName)) 
                {
                    Charts[chartName].Series.Add(seriesName, new Series(seriesName, seriesType, unit));
                }

                //Add our value:
                Charts[chartName].Series[seriesName].Values.Add(new ChartPoint(time, value));
            }
        }

        /// <summary>
        /// Sample the current equity of the strategy directly with time-value pair.
        /// </summary>
        /// <param name="time">Current backtest time.</param>
        /// <param name="value">Current equity value.</param>
        public void SampleEquity(DateTime time, decimal value) 
        {
            //Sample the Equity Value:
            Sample("Strategy Equity", ChartType.Stacked, "Equity", SeriesType.Candle, time, value);

            //Recalculate the days processed:
            _daysProcessed = (time - _job.PeriodStart).TotalDays;
        }

        /// <summary>
        /// Sample the current daily performance directly with a time-value pair.
        /// </summary>
        /// <param name="time">Current backtest date.</param>
        /// <param name="value">Current daily performance value.</param>
        public void SamplePerformance(DateTime time, decimal value) 
        {
            //Added a second chart to equity plot - daily perforamnce:
            Sample("Strategy Equity", ChartType.Stacked, "Daily Performance", SeriesType.Bar, time, value, "%");
        }

        /// <summary>
        /// Sample the current benchmark performance directly with a time-value pair.
        /// </summary>
        /// <param name="time">Current backtest date.</param>
        /// <param name="value">Current benchmark value.</param>
        /// <seealso cref="IResultHandler.Sample"/>
        public void SampleBenchmark(DateTime time, decimal value)
        {
            Sample("Benchmark", ChartType.Stacked, "Benchmark", SeriesType.Line, time, value);
        }

        /// <summary>
        /// Add a range of samples from the users algorithms to the end of our current list.
        /// </summary>
        /// <param name="updates">Chart updates since the last request.</param>
        public void SampleRange(List<Chart> updates) 
        {
            lock (_chartLock) 
            {
                foreach (var update in updates) 
                {
                    //Create the chart if it doesn't exist already:
                    if (!Charts.ContainsKey(update.Name)) 
                    {
                        Charts.AddOrUpdate(update.Name, new Chart(update.Name, update.ChartType));
                    }

                    //Add these samples to this chart.
                    foreach (var series in update.Series.Values) 
                    {
                        //If we don't already have this record, its the first packet
                        if (!Charts[update.Name].Series.ContainsKey(series.Name))
                        {
                            Charts[update.Name].Series.Add(series.Name, new Series(series.Name, series.SeriesType));
                        }

                        //We already have this record, so just the new samples to the end:
                        Charts[update.Name].Series[series.Name].Values.AddRange(series.Values);
                    }
                }
            }
        }

        /// <summary>
        /// Terminate the result thread and apply any required exit proceedures.
        /// </summary>
        public void Exit() 
        {
            //Process all the log messages and send them to the S3:
            var logURL = ProcessLogMessages(_job);
            if (logURL != "") DebugMessage("Your log was successfully created and can be downloaded from: " + logURL);

            //Set exit flag, and wait for the messages to send:
            _exitTriggered = true;
        }

        /// <summary>
        /// Send a new order event to the browser.
        /// </summary>
        /// <remarks>In backtesting the order events are not sent because it would generate a high load of messaging.</remarks>
        /// <param name="newEvent">New order event details</param>
        public void OrderEvent(OrderEvent newEvent)
        { 
            // NOP. Don't do any order event processing for results in backtest mode.
        }


        /// <summary>
        /// Send an algorithm status update to the browser.
        /// </summary>
        /// <param name="algorithmId">Algorithm id for the status update.</param>
        /// <param name="status">Status enum value.</param>
        /// <param name="message">Additional optional status message.</param>
        /// <remarks>In backtesting we do not send the algorithm status updates.</remarks>
        public void SendStatusUpdate(string algorithmId, AlgorithmStatus status, string message = "")
        { 
            //NOP. Don't send status for backtests
        }

        /// <summary>
        /// Sample the asset prices to generate plots.
        /// </summary>
        /// <param name="symbol">Symbol we're sampling.</param>
        /// <param name="time">Time of sample</param>
        /// <param name="value">Value of the asset price</param>
        public void SampleAssetPrices(Symbol symbol, DateTime time, decimal value)
        {
            //NOP. Don't sample asset prices in console.
        }

        /// <summary>
        /// Purge/clear any outstanding messages in message queue.
        /// </summary>
        public void PurgeQueue() 
        {
            Messages.Clear();
        }

        /// <summary>
        /// Set the current runtime statistics of the algorithm. 
        /// These are banner/title statistics which show at the top of the live trading results.
        /// </summary>
        /// <param name="key">Runtime headline statistic name</param>
        /// <param name="value">Runtime headline statistic value</param>
        public void RuntimeStatistic(string key, string value)
        {
            // Do nothing. Banner statistics don't apply in backtesting.
        }

        /// <summary>
        /// Process log messages to ensure the meet the user caps and send them to storage.
        /// </summary>
        /// <param name="job">Algorithm job/task packet</param>
        /// <returns>String URL of log</returns>
        private string ProcessLogMessages(AlgorithmNodePacket job)
        {
            var remoteUrl = @"http://data.quantconnect.com/";
            var logLength = 0;

            try
            {
                //Return nothing if there's no log messages to procesS:
                if (!_log.Any()) return "";

                //Get the max length allowed for the algorithm:
                var allowance = _api.ReadLogAllowance(job.UserId, job.Channel);
                var logBacktestMax = allowance[0];
                var logDailyMax = allowance[1];
                var logRemaining = Math.Min(logBacktestMax, allowance[2]); //Minimum of maxium backtest or remaining allowance.
                var hitLimit = false;
                var serialized = "";

                var key = "backtests/" + job.UserId + "/" + job.ProjectId + "/" + job.AlgorithmId + "-log.txt";
                remoteUrl += key;

                foreach (var line in _log)
                {
                    if ((logLength + line.Length) < logRemaining)
                    {
                        serialized += line + "\r\n";
                        logLength += line.Length;
                    }
                    else
                    {
                        var btMax = Math.Round((double)logBacktestMax / 1024, 0) + "kb";
                        var dyMax = Math.Round((double)logDailyMax / 1024, 0) + "kb";

                        //Same cap notice for both free & subscribers
                        var requestMore = "";
                        var capNotice = "You currently have a maximum of " + btMax + " of log data per backtest, and " + dyMax + " total max per day.";
                        DebugMessage("You currently have a maximum of " + btMax + " of log data per backtest remaining, and " + dyMax + " total max per day.");
                        
                        //Data providers set max log limits and require email requests for extensions
                        if (job.UserPlan == UserPlan.Free)
                        {
                            requestMore ="Please upgrade your account and contact us to request more allocation here: https://www.quantconnect.com/contact"; 
                        }
                        else
                        {
                            requestMore = "If you require more please briefly explain request for more allocation here: https://www.quantconnect.com/contact";
                        }
                        DebugMessage(requestMore);
                        serialized += capNotice;
                        serialized += requestMore;
                        hitLimit = true;
                        break;
                    }
                }

                //Save the log: Upload this file to S3:
                _api.Store(serialized, key, StoragePermissions.Public);
                //Record the data usage:
                _api.UpdateDailyLogUsed(job.UserId, job.AlgorithmId, remoteUrl, logLength, job.Channel, hitLimit);
            }
            catch (Exception err)
            {
                Log.Error("BacktestingResultHandler.ProcessLogMessages(): " + err.Message);
            }
            Log.Trace("BacktestingResultHandler.ProcessLogMessages(): Ready: " + remoteUrl);
            return remoteUrl;
        }

        /// <summary>
        /// Set the chart subscription we want data for. Not used in backtesting.
        /// </summary>
        public void SetChartSubscription(string symbol)
        {
            //NOP.
        }

        /// <summary>
        /// Process the synchronous result events, sampling and message reading. 
        /// This method is triggered from the algorithm manager thread.
        /// </summary>
        /// <remarks>Prime candidate for putting into a base class. Is identical across all result handlers.</remarks>
        public void ProcessSynchronousEvents(bool forceProcess = false)
        {
            var time = _algorithm.Time;

            if (time > _nextSample || forceProcess)
            {
                //Set next sample time: 4000 samples per backtest
                _nextSample = time.Add(ResamplePeriod);

                //Sample the portfolio value over time for chart.
                SampleEquity(time, Math.Round(_algorithm.Portfolio.TotalPortfolioValue, 4));

                //Also add the user samples / plots to the result handler tracking:
                SampleRange(_algorithm.GetChartUpdates());

                //Sample the asset pricing:
                foreach (var security in _algorithm.Securities.Values)
                {
                    SampleAssetPrices(security.Symbol, time, security.Price);
                }
            }

            //Send out the debug messages:
            _algorithm.DebugMessages.ForEach(x => DebugMessage(x));
            _algorithm.DebugMessages.Clear();

            //Send out the error messages:
            _algorithm.ErrorMessages.ForEach(x => ErrorMessage(x));
            _algorithm.ErrorMessages.Clear();

            //Send out the log messages:
            _algorithm.LogMessages.ForEach(x => LogMessage(x));
            _algorithm.LogMessages.Clear();
        }

    } // End Result Handler Thread:

} // End Namespace
