using Dfs.WayneChina.GilbarcoDispenserPayTerminal;
using Dfs.WayneChina.GilbarcoDispenserPayTerminal.MessageEntities;
using Dfs.WayneChina.GilbarcoDispenserPayTerminal.MessageEntities.Incoming;
using Dfs.WayneChina.GilbarcoDispenserPayTerminal.MessageEntities.Outgoing;
using Edge.Core.IndustryStandardInterface.Pump;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Timers;
using Wayne.FDCPOSLibrary;

namespace Dfs.WayneChina.GilbarcoPos
{
    public class TerminalManager
    {
        private class SeqNoGenerator
        {
            private List<byte> seqNoList;
            private int i = 0;

            public SeqNoGenerator()
            {
                seqNoList = new List<byte>();
                for (byte i = 0x5F; i >= 0x40; i--)
                {
                    seqNoList.Add(i);
                }
            }

            public byte GetNextSeqNo()
            {
                i++;
                return seqNoList[i % 32];
            }
        }

        public byte PumpId { get; }

        private GilbarcoPosApp PosApp { get; }

        private GilbarcoPayTerminalHandler terminal;

        private Timer timer;
        private int _interval;

        private byte seqNo;

        private SeqNoGenerator Sqg { get; }

        private Queue<FdcTransaction> fillings = new Queue<FdcTransaction>(10);

        private NLog.Logger logger = NLog.LogManager.LoadConfiguration("NLog.config").GetLogger("IPosPlusApp");

        public TerminalManager(GilbarcoPosApp posApp, GilbarcoPayTerminalHandler terminalHandler, int interval)
        {
            PosApp = posApp;
            terminal = terminalHandler;
            _interval = interval;
            PumpId = terminalHandler.PumpId;

            Sqg = new SeqNoGenerator();
        }

        public void Start()
        {
            timer = new Timer();
            timer.Interval = _interval;
            timer.Elapsed += Timer_Elapsed;
            timer.Start();
        }

        private void Timer_Elapsed(object sender, ElapsedEventArgs e)
        {
            SendCheckCommand();
        }

        private byte GetNextSeqNo()
        {
            return (byte)(seqNo++ % 0x7F);
        }

        private void SendCheckCommand()
        {
            logger.Debug($"Checking pump {PumpId}");
            CheckCommand checkCommand = new CheckCommand();
            checkCommand.DestinationAddress = terminal.TerminalAddress;
            checkCommand.SourceAddress = terminal.Address;
            checkCommand.FrameSqNoByte = Sqg.GetNextSeqNo();
            checkCommand.Time = long.Parse(DateTime.Now.ToString("yyyyMMddHHmmss"));
            checkCommand.BaseBlacklistVersion = PosApp.CurrentVersionInfo.BaseBlacklistVersion;
            checkCommand.AddBlacklistVersion = PosApp.CurrentVersionInfo.AddBlacklistVersion;
            checkCommand.DeleteBlacklistVersion = PosApp.CurrentVersionInfo.DeleteBlacklistVersion;
            checkCommand.WhitelistVersion = PosApp.CurrentVersionInfo.WhitelistVersion;
            checkCommand.PriceVersion = PosApp.CurrentVersionInfo.PriceVersion;
            checkCommand.StationGeneralInfoVersion = PosApp.CurrentVersionInfo.StationGeneralInfoVersion;
            checkCommand.PrivateDataDownloadFlag = PosApp.CurrentVersionInfo.PrivateDataDownloadFlag;
            checkCommand.SoftwareDownloadFlag = PosApp.CurrentVersionInfo.SoftwareDownloadFlag;

            terminal.Write(checkCommand);
        }

        public void HandleInfoCommand(InfoCommand command)
        {
            logger.Debug("Handling INFO command");

            if (command.Count > 0)
            {
                if (command.CardInsertedStates != null)
                {
                }
                else if (command.NozzleOperatingStates != null)
                {
                    var nozzleOperationState = command.NozzleOperatingStates[0];
                    if (nozzleOperationState.State == NozzleOperatingState.PumpStateChangeCode.NozzleLiftOrFueling)
                    {
                        if (nozzleOperationState.PRC == 0)
                        {
                            //Assume this is nozzle lift => FDC_CALLING
                            terminal.UpdatePumpState(LogicalDeviceState.FDC_CALLING);
                        }
                        else if (nozzleOperationState.PRC > 0 && nozzleOperationState.VOL == 0)
                        {
                            //Assume this is FDC_AUTHORIZED
                            terminal.UpdatePumpState(LogicalDeviceState.FDC_AUTHORISED);
                        }
                        else if (nozzleOperationState.VOL > 0)
                        {
                            //Assume this is FDC_FUELLING
                            terminal.UpdatePumpState(LogicalDeviceState.FDC_FUELLING);

                            terminal.UpdateFuelingStatus(new FdcTransaction
                            {
                                Finished = false,
                                Nozzle = new LogicalNozzle(PumpId, 1, 1, null),
                                Amount = nozzleOperationState.AMN,
                                Price = nozzleOperationState.PRC,
                                Volumn = nozzleOperationState.VOL
                            });
                        }
                    }
                }
            }
            else
            {
                //Terminal is running fine for now.
            }
        }

        public void HandleTransactionData(TransactionData transactionData)
        {
            logger.Info("Handling TransactionData");

            //First trigger pump state change, idle again => FDC_READY
            terminal.UpdatePumpState(Wayne.FDCPOSLibrary.LogicalDeviceState.FDC_READY);

            // Handle possible duplicate
            var filling = fillings.FirstOrDefault(f => f.Nozzle.PumpId == transactionData.NozzleNo 
                && f.SequenceNumberGeneratedOnPhysicalPump == transactionData.PosTtc);

            if (filling == null)
            {
                //Fuelling is done now, trigger as well the fueling status change

                var trans = new FdcTransaction
                {
                    Finished = true,
                    Nozzle = new LogicalNozzle(PumpId, 1, 1, null),
                    Amount = transactionData.Amount,
                    Price = transactionData.Price,
                    Volumn = transactionData.Volume,
                    VolumeTotalizer = Convert.ToInt32(transactionData.VolumeTotalizer),
                    SequenceNumberGeneratedOnPhysicalPump = transactionData.PosTtc
                };

                terminal.UpdateFuelingStatus(trans);

                if (fillings.Count >= 10)
                {
                    fillings.Dequeue();
                }

                fillings.Enqueue(trans);
            }

            var ack = CreateTransactionDataAck(0);
            terminal.Write(ack);
        }

        private TransactionDataAck CreateTransactionDataAck(byte result)
        {
            TransactionDataAck ack = new TransactionDataAck();
            ack.DestinationAddress = terminal.TerminalAddress;
            ack.SourceAddress = terminal.Address;
            ack.FrameSqNoByte = Sqg.GetNextSeqNo();
            ack.Result = result;

            return ack;
        }
    }
}