namespace CordonelPreadjustmentUi.Processes.Actions
{
    using Newtonsoft.Json;

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

    using Xylem.Common.CommonCore.Configuration;
    using Xylem.Common.Hardware.WaterMeter.Genesis.Registers;
    using Xylem.Common.Logic.SoftwareAccessHelper;

    using static CordonelPreadjustmentUi.PreAdjustmentControl;

    /// <summary>
    /// Process for cordonel water meters with pressure sensor.
    /// </summary>
    /// <remarks date="2023-05-23" author="Stoyan Zlatev">
    /// Just started implementing pressure test for water meters with pressure sensor. 
    /// </remarks>
    public class PressureTestProcess : BaseProcess
    {
        /// <summary>
        /// Read / Write is pressure present for the water meter. 
        /// </summary>
        /// <remarks date="2023-05-23" author="Stoyan Zlatev">
        /// Just started implementing pressure test for water meters with pressure sensor. 
        /// </remarks>
        private const string PRESSURE_PRESENT = "METROLOGYASST_PressurePresent";
        /// <summary>
        /// Read / Write pressure measurements for the water meter. 
        /// </summary>
        /// <remarks date="2023-05-23" author="Stoyan Zlatev">
        /// Just started implementing pressure test for water meters with pressure sensor. 
        /// </remarks>
        private const string PRESSURE_MEASURE = "METROLOGYASST_PressureMeasure";

        /// <summary>
        /// Constructor for passing parameters to the base constructor of the derived class.
        /// </summary>
        /// <param name="processName">The name used to show into the GUI.</param>
        /// <param name="panelState">TODO: Get the right description. Probably the state for the box into the GUI. ???</param>
        /// <param name="performMessage">TODO: Get the right description. Probably the success message to show into the GUI. ???</param>
        /// <param name="failedMessage">TODO: Get the right description. Probably the error message to show into the GUI. ???</param>
        /// <param name="expectedTimeS">TODO: Get the right description. Probably the expected time for process the pressure tests. ???</param>
        /// <remarks date="2023-05-23" author="Stoyan Zlatev">
        /// Just started implementing pressure test for water meters with pressure sensor. 
        /// </remarks>
        public PressureTestProcess(string processName, StatusPanelItems panelState, string performMessage, string failedMessage, int? expectedTimeS) 
            : base(processName, panelState, performMessage, failedMessage, expectedTimeS)
        {
        }

        /// <summary>
        /// Determinates and initializes a list of pressure measure tests processes on the logedin cordonels with pressure sensor.
        /// Programm workflow for Cordonels with pressure sensor. 
        /// When any of the water meters has presure sensor - load the test specification.
        /// Acording to the test specification process all meters, also the referenz on workplaces 11 and 12.
        /// <list type="number">
        ///     <listheader>Measurement as follow.</listheader>
        ///     <item>Measure starts with <see cref="PRESSURE_MEASURE"/> = 1</item> 
        ///     <item>Then registry is readeded and comaired to the referenz meters acording to the specification.</item> 
        /// </list>
        /// </summary>
        /// <returns>Returns a <see cref="List{Task}"/> for processing the pressure tests on the goggedin cordonels.</returns>
        /// <remarks date="2023-05-23" author="Stoyan Zlatev">
        /// Just started implementing pressure test for water meters with pressure sensor. 
        /// </remarks>
        public override List<Task> StartWork()
        {
            /// List of the processes to start.
            var listOfPresureTestTasks = new List<Task>();
            var pressureTestSpecification = default(PressureTestSpecification);
            var pressureTestSpecificationLoaded = false;
            /// Just to not lose from focus the process progrss object.
            var processProgress = base.CurrentProcessProgress;
            var minPressureReferenzValue = default(int?);
            var maxPressureReferenzValue = default(int?);
            
            /// Looping trough all <see cref="MeterStateControl"/>s to determinate whitch are with pressure sensor.
            foreach (var meterStateControl in base.MeterStateCtls)
            {
                /// If the meter is enabled and pressure sensor is present a new pressure mesure task should be initialized and added to the processes list.
                if (meterStateControl.IsEnabled)
                {
                    /// Getting the meter object from the state control.
                    var meter = meterStateControl.Meter;
                    /// Reads the buffer for determinating if the pressure sensor is present.
                    var isPressurePresentBuffer = meter.ReadRegister(PRESSURE_PRESENT);
                    /// Converted value for determinating if the pressure sensor is present.
                    var isPressurePresent = RegisterConverter.ByteArrayToValue<bool>(isPressurePresentBuffer);

                    if (!isPressurePresent)
                    {
                        processProgress.DebugMessage($"Watermeter has no pressure sensor!", meterStateControl.Slot, "DC", meter.PcbId);

                        continue;
                    }

                    /// Loads the pressure test specification from the defined web service if not yet loaded.
                    if (pressureTestSpecification is null && !pressureTestSpecificationLoaded)
                    {
                        pressureTestSpecificationLoaded = true;
                        pressureTestSpecification = this.LoadPressureTestSpecification();

                        /// if loading fails
                        if (pressureTestSpecification is null)
                        {
                            processProgress.DebugMessage($"Test specification could not be loaded properly!", meterStateControl.Slot, "DC", meter.PcbId);

                            // TODO: Handle possible exceptions by making http request.
                            continue;
                        }
                    }

                    /// Initialize min and max referenz values ones for all meters
                    if (minPressureReferenzValue is null)
                    {
                        /// setting the min and max values on their oposit values.
                        /// checking the equality later will set up a value by 1 or more referenz meters.
                        minPressureReferenzValue = int.MaxValue;
                        maxPressureReferenzValue = int.MinValue;

                        if (processProgress.Setting.GetTempUseTempFlansh() || TempMeterStateCtls.Any(a => a.IsEnabled))
                        {
                            /// Determinates the min and max values aus temperatur meters list.
                            foreach (var referenzMeterState in base.TempMeterStateCtls)
                            {
                                if (referenzMeterState.IsEnabled)
                                {
                                    var referenzMeter = referenzMeterState.Meter;
                                    /// Reset meter pressure
                                    referenzMeter.WriteRegister(PRESSURE_MEASURE, 1);

                                    if (!referenzMeter.IsLoggedOn)
                                    {
                                        referenzMeter.Login();
                                    }

                                    var referenzPressureBuffer = referenzMeter.ReadRegister(PRESSURE_MEASURE);
                                    var referenzPressure = RegisterConverter.ByteArrayToValue<int>(referenzPressureBuffer);
                                    
                                    if (referenzPressure < minPressureReferenzValue)
                                    {
                                        minPressureReferenzValue = referenzPressure;
                                    }

                                    if (referenzPressure > maxPressureReferenzValue)
                                    {
                                        maxPressureReferenzValue = referenzPressure;
                                    }
                                }
                            }
                        }

                        /// Continue if min pressure value is still its oposit for the type. There was no referenz zehler found.
                        if (minPressureReferenzValue == int.MaxValue)
                        {
                            processProgress.DebugMessage($"No referenz watermeter found!", meterStateControl.Slot, "DC", meter.PcbId);

                            continue;
                        }

                        listOfPresureTestTasks.Add(new Task<bool>(() =>
                        {
                            var measuredTestValues = new int[pressureTestSpecification.NumberOfMeasurements];
                            var measurementDelyInS = pressureTestSpecification.TimeMeasurementsInS * 1000;
                            var numberOfMeasurements = pressureTestSpecification.NumberOfMeasurements;
                            var testDate = DateTime.Now;

                            for (int measurement = 0; measurement < numberOfMeasurements; measurement++)
                            {
                                /// Reset meter pressure
                                meter.WriteRegister(PRESSURE_MEASURE, 1);

                                /// Read the new meter pressure
                                var pressureMeasureBuffer = meter.ReadRegister(PRESSURE_MEASURE);
                                var pressureInPascals = RegisterConverter.ByteArrayToValue<int>(pressureMeasureBuffer);

                                measuredTestValues[measurement] = pressureInPascals;
                                processProgress.DebugMessage($"Measure {measurement + 1}: {pressureInPascals}Pa", meterStateControl.Slot, "DC", meter.PcbId);

                                /// Dely only for first n - 1 measurements
                                if (measurement < numberOfMeasurements - 1)
                                {
                                    Thread.Sleep(measurementDelyInS);
                                }
                            }

                            var avgPressure = (int)measuredTestValues.Average();
                            var testPassed = minPressureReferenzValue <= avgPressure && avgPressure <= maxPressureReferenzValue;
                            var avgPressureInBars = avgPressure / 100_000F;

                            processProgress.DebugMessage($"Average pressure: {avgPressure}Pa", meterStateControl.Slot, "DC", meter.PcbId);
                            processProgress.DebugMessage($"Average pressure: {avgPressureInBars}Bar", meterStateControl.Slot, "DC", meter.PcbId);

                            if (!this.PostPressureTestResult(meter.PcbId, avgPressureInBars, testPassed, testDate))
                            {
                                processProgress.DebugMessage($"Test result was not posted!", meterStateControl.Slot, "DC", meter.PcbId);

                                return false;
                            }

                            return testPassed;
                        }));
                    }
                }
            }

            return listOfPresureTestTasks;
        }

        private PressureTestSpecification LoadPressureTestSpecification()
        {
            try
            {
                var responseContent = LocalWebRequest.GetRequest(ServiceUrls.GetPressureSensorSpecificationURL);

                return JsonConvert.DeserializeObject<PressureTestSpecification>(responseContent);
            }
            catch (Exception e)
            {
                return null;
            }
        }

        private bool PostPressureTestResult(string pcbIdText, float avgPressure, bool passed, DateTime testDate)
        {
            try
            {
                return LocalWebRequest.PostRequestAsync(ServiceUrls.PostPressureSensorResultURL, json: new
                {
                    PcbId = int.TryParse(pcbIdText, out int pcbId) ? pcbId : default(int?),
                    AvgPressureInBar = avgPressure,
                    TestPassed = passed,
                    TestDate = testDate,
                });
            }
            catch (Exception e)
            {
                return false;
            }
        }
    }

    internal class PressureTestSpecification
    {
        public int NumberOfMeasurements { get; set; }

        public int TimeMeasurementsInS { get; set; }

        public float MaxDeviationInBar { get; set; }
    }
}