//******************************************************************************************************
//  PowerCalculator.cs - Gbtc
//
//  Copyright © 2012, Grid Protection Alliance.  All Rights Reserved.
//
//  Licensed to the Grid Protection Alliance (GPA) under one or more contributor license agreements. See
//  the NOTICE file distributed with this work for additional information regarding copyright ownership.
//  The GPA licenses this file to you under the MIT License (MIT), 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.opensource.org/licenses/MIT
//
//  Unless agreed to in writing, the subject software distributed under the License is distributed on an
//  "AS-IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. Refer to the
//  License for the specific language governing permissions and limitations.
//
//  Code Modification History:
//  ----------------------------------------------------------------------------------------------------
//  05/16/2012 - J. Ritchie Carroll
//       Generated original version of source code.
//  12/13/2012 - Starlynn Danyelle Gilliam
//       Modified Header.
//
//******************************************************************************************************

using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using GSF;
using GSF.Collections;
using GSF.TimeSeries;
using GSF.TimeSeries.Adapters;
using GSF.Units;
using GSF.Units.EE;
using PhasorProtocolAdapters;

namespace PowerCalculations
{
    /// <summary>
    /// Calculates MW and MVAR using Voltage and Current Magnitude and Angle signals input to the adapter.
    /// </summary>
    [Description("Power Calculator: Calculates power and reactive power for synchrophasor measurements")]
    public class PowerCalculator : CalculatedMeasurementBase
    {
        #region [ Members ]

        // Constants
        private const double SqrtOf3 = 1.7320508075688772935274463415059D;

        // Fields
        private MeasurementKey m_voltageAngle;
        private MeasurementKey m_voltageMagnitude;
        private MeasurementKey m_currentAngle;
        private MeasurementKey m_currentMagnitude;
        private bool m_trackRecentValues;
        private int m_sampleSize;
        private List<double> m_powerSample;
        private List<double> m_reactivePowerSample;

        // Important: Make sure output definition defines points in the following order
        private enum Output
        {
            Power,
            ReactivePower
        }

        #endregion

        #region [ Properties ]

        /// <summary>
        /// Gets or sets flag that determines if the last few values should be monitored.
        /// </summary>
        [ConnectionStringParameter,
        Description("Flag that determines if the last few values should be monitored."),
        DefaultValue(true)]
        public bool TrackRecentValues
        {
            get
            {
                return m_trackRecentValues;
            }
            set
            {
                m_trackRecentValues = value;
            }
        }

        /// <summary>
        /// Gets or sets the sample size of the data to be monitored.
        /// </summary>
        [ConnectionStringParameter,
        Description("Define the sample size of the data to be monitored."),
        DefaultValue(5)]
        public int SampleSize
        {
            get
            {
                return m_sampleSize;
            }
            set
            {
                m_sampleSize = value;
            }
        }

        /// <summary>
        /// Gets the flag indicating if this adapter supports temporal processing.
        /// </summary>
        public override bool SupportsTemporalProcessing
        {
            get
            {
                return true;
            }
        }

        /// <summary>
        /// Returns the detailed status of the <see cref="PowerCalculator"/>.
        /// </summary>
        public override string Status
        {
            get
            {
                const int ValuesToShow = 3;

                StringBuilder status = new StringBuilder();

                if (m_trackRecentValues)
                {
                    status.Append("         Last power values: ");

                    lock (m_powerSample)
                    {
                        // Display last several values
                        if (m_powerSample.Count > ValuesToShow)
                            status.Append(m_powerSample.GetRange(m_powerSample.Count - ValuesToShow - 1, ValuesToShow).Select(v => v.ToString("0.00MW")).ToDelimitedString(", "));
                        else
                            status.Append("Not enough values calculated yet...");
                    }
                    status.AppendLine();

                    status.Append("Last reactive power values: ");

                    lock (m_reactivePowerSample)
                    {
                        // Display last several values
                        if (m_reactivePowerSample.Count > ValuesToShow)
                            status.Append(m_reactivePowerSample.GetRange(m_reactivePowerSample.Count - ValuesToShow - 1, ValuesToShow).Select(v => v.ToString("0.00MVAR")).ToDelimitedString(", "));
                        else
                            status.Append("Not enough values calculated yet...");
                    }
                    status.AppendLine();
                }

                status.Append(base.Status);

                return status.ToString();
            }
        }

        #endregion

        #region [ Methods ]

        /// <summary>
        /// Initializes the <see cref="PowerCalculator"/>.
        /// </summary>
        public override void Initialize()
        {
            base.Initialize();

            Dictionary<string, string> settings = Settings;
            string setting;

            // Load parameters
            if (settings.TryGetValue("trackRecentValues", out setting))
                m_trackRecentValues = setting.ParseBoolean();
            else
                m_trackRecentValues = true;

            if (settings.TryGetValue("sampleSize", out setting))            // Data sample size to monitor, in seconds
                m_sampleSize = int.Parse(setting);
            else
                m_sampleSize = 5;

            // Load needed phase angle and magnitude measurement keys from defined InputMeasurementKeys
            m_voltageAngle = InputMeasurementKeys.Where((key, index) => InputMeasurementKeyTypes[index] == SignalType.VPHA).FirstOrDefault();
            m_voltageMagnitude = InputMeasurementKeys.Where((key, index) => InputMeasurementKeyTypes[index] == SignalType.VPHM).FirstOrDefault();
            m_currentAngle = InputMeasurementKeys.Where((key, index) => InputMeasurementKeyTypes[index] == SignalType.IPHA).FirstOrDefault();
            m_currentMagnitude = InputMeasurementKeys.Where((key, index) => InputMeasurementKeyTypes[index] == SignalType.IPHM).FirstOrDefault();

            if ((object)m_voltageAngle == null || m_voltageAngle.ID == 0)
                throw new InvalidOperationException("No voltage angle input was defined - one voltage angle input measurement is required for the power calculator.");

            if ((object)m_voltageMagnitude == null || m_voltageMagnitude.ID == 0)
                throw new InvalidOperationException("No voltage magnitude input was defined - one voltage magnitude input measurement is required for the power calculator.");

            if ((object)m_currentAngle == null || m_currentAngle.ID == 0)
                throw new InvalidOperationException("No current angle input was defined - one current angle input measurement is required for the power calculator.");

            if ((object)m_currentMagnitude == null || m_currentMagnitude.ID == 0)
                throw new InvalidOperationException("No current magnitude input measurement was defined - one current magnitude input measurement is required for the power calculator.");

            // Make sure only these four phasor measurements are used as input (any others will be ignored)
            InputMeasurementKeys = new[] { m_voltageAngle, m_voltageMagnitude, m_currentAngle, m_currentMagnitude };

            // Validate output measurements
            if (OutputMeasurements.Length < Enum.GetValues(typeof(Output)).Length)
                throw new InvalidOperationException("Not enough output measurements were specified for the power calculator, expecting measurements for the \"Calculated Power\" and the \"Calculated Reactive Power\" - in this order.");

            if (m_trackRecentValues)
            {
                m_powerSample = new List<double>();
                m_reactivePowerSample = new List<double>();
            }

            // Assign a default adapter name to be used if power calculator is loaded as part of automated collection
            if (string.IsNullOrWhiteSpace(Name))
                Name = string.Format("PC!{0}", OutputMeasurements[(int)Output.Power].Key);
        }

        /// <summary>
        /// Publish frame of time-aligned collection of measurement values that arrived within the defined lag time.
        /// </summary>
        /// <param name="frame">Frame of measurements with the same timestamp that arrived within lag time that are ready for processing.</param>
        /// <param name="index">Index of frame within a second ranging from zero to frames per second - 1.</param>
        protected override void PublishFrame(IFrame frame, int index)
        {
            double power = double.NaN, reactivePower = double.NaN;

            try
            {
                ConcurrentDictionary<MeasurementKey, IMeasurement> measurements = frame.Measurements;
                double voltageMagnitude = 0.0D, voltageAngle = 0.0D, currentMagnitude = 0.0D, currentAngle = 0.0D;
                IMeasurement measurement;
                bool allValuesReceived = false;

                // Get each needed value from this frame
                if (measurements.TryGetValue(m_voltageMagnitude, out measurement) && measurement.ValueQualityIsGood())
                {
                    // Get voltage magnitude value
                    voltageMagnitude = measurement.AdjustedValue;

                    if (measurements.TryGetValue(m_voltageAngle, out measurement) && measurement.ValueQualityIsGood())
                    {
                        // Get voltage angle value
                        voltageAngle = measurement.AdjustedValue;

                        if (measurements.TryGetValue(m_currentMagnitude, out measurement) && measurement.ValueQualityIsGood())
                        {
                            // Get current magnitude value
                            currentMagnitude = measurement.AdjustedValue;

                            if (measurements.TryGetValue(m_currentAngle, out measurement) && measurement.ValueQualityIsGood())
                            {
                                // Get current angle value
                                currentAngle = measurement.AdjustedValue;
                                allValuesReceived = true;
                            }
                        }
                    }
                }

                if (allValuesReceived)
                {
                    double angleDifference = Math.Abs(voltageAngle - currentAngle);

                    if (angleDifference > 180)
                        angleDifference = 360 - angleDifference;

                    // Convert phase angle difference to radians
                    double impedancePhaseAngle = Angle.FromDegrees(angleDifference);

                    // Calculate line-to-neutral apparent power (S) vector magnitude in Mega volt-amps
                    double apparentPower = SqrtOf3 * (Math.Abs(voltageMagnitude) / SI.Mega) * Math.Abs(currentMagnitude);

                    // Calculate power (P) and reactive power (Q)
                    power = apparentPower * Math.Cos(impedancePhaseAngle);
                    reactivePower = apparentPower * Math.Sin(impedancePhaseAngle);

                    if (m_trackRecentValues)
                    {
                        // Add latest calculated power to data sample
                        lock (m_powerSample)
                        {
                            m_powerSample.Add(power);

                            // Maintain sample size
                            while (m_powerSample.Count > m_sampleSize)
                                m_powerSample.RemoveAt(0);
                        }

                        // Add latest calculated reactive power to data sample
                        lock (m_reactivePowerSample)
                        {
                            m_reactivePowerSample.Add(reactivePower);

                            // Maintain sample size
                            while (m_reactivePowerSample.Count > m_sampleSize)
                                m_reactivePowerSample.RemoveAt(0);
                        }
                    }
                }
            }
            finally
            {

                IMeasurement[] outputMeasurements = OutputMeasurements;
                Measurement powerMeasurement = Measurement.Clone(outputMeasurements[(int)Output.Power], power, frame.Timestamp);
                Measurement stdevMeasurement = Measurement.Clone(outputMeasurements[(int)Output.ReactivePower], reactivePower, frame.Timestamp);

                // Provide calculated measurements for external consumption
                OnNewMeasurements(new IMeasurement[] { powerMeasurement, stdevMeasurement });
            }
        }

        #endregion
    }
}