using Microsoft.FlightSimulator.SimConnect;
using MSFSPopoutPanelManager.Shared;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Dynamic;
using System.Runtime.InteropServices;


namespace MSFSPopoutPanelManager.FsConnector
{
    public class SimConnector
    {
        private const int MSFS_CONNECTION_RETRY_TIMEOUT = 1000;     // timeout to retry connection to MSFS via Simconnect in milliseconds
        private const int WM_USER_SIMCONNECT = 0x402;
        private SimConnect _simConnect;
        private System.Timers.Timer _timer;

        public event EventHandler<EventArgs<dynamic>> OnReceivedData;
        public event EventHandler OnConnected;
        public event EventHandler OnDisconnected;
        public event EventHandler<EventArgs<SimConnectSystemEvent>> OnReceiveSystemEvent;

        public dynamic SimData { get; set; }

        public void Start()
        {
            _timer = new System.Timers.Timer();
            _timer.Interval = MSFS_CONNECTION_RETRY_TIMEOUT;
            _timer.Enabled = true;
            _timer.Elapsed += (source, e) =>
            {
                try
                {
                    if (_simConnect == null)
                    {
                         _simConnect = new SimConnect("MSFS Pop Out Panel Manager", Process.GetCurrentProcess().MainWindowHandle, WM_USER_SIMCONNECT, null, 0);

                        _simConnect.OnRecvQuit += HandleOnRecvQuit;
                        _simConnect.OnRecvException += HandleOnRecvException;
                        _simConnect.OnRecvSimobjectDataBytype += HandleOnRecvSimobjectDataBytype;
                        _simConnect.OnRecvEvent += HandleOnReceiveEvent;

                        _simConnect.SubscribeToSystemEvent(SimConnectSystemEvent.SIMSTART, "SimStart");
                        _simConnect.SubscribeToSystemEvent(SimConnectSystemEvent.SIMSTOP, "SimStop");
                        _simConnect.SubscribeToSystemEvent(SimConnectSystemEvent.VIEW, "View");
                        
                        // Setup SimConnect data structure definition using SimConnectStruct and SimConnect data definitions
                        var definitions = DataDefinition.GetDefinition();
                        foreach (var (PropName, SimConnectName, SimConnectUnit, SimConnectDataType, ObjectType) in definitions)
                            _simConnect.AddToDataDefinition(SimConnectDefinition.SimConnectDataStruct, SimConnectName, SimConnectUnit, SimConnectDataType, 0.0f, SimConnect.SIMCONNECT_UNUSED);
                        _simConnect.RegisterDataDefineStruct<SimConnectStruct>(SimConnectDefinition.SimConnectDataStruct);

                        // Setup SimEvent mapping
                        foreach (var item in Enum.GetValues(typeof(ActionEvent)))
                        {
                            if (item.ToString().StartsWith("KEY_"))
                                _simConnect.MapClientEventToSimEvent((ActionEvent)item, item.ToString()[4..]);
                        }

                        _timer.Enabled = false;

                        System.Threading.Thread.Sleep(2000);

                        Debug.WriteLine("SimConnect is connected");

                        OnConnected?.Invoke(this, null);
                    }
                }
                catch (COMException)
                {
                    // handle SimConnect instantiation error when MSFS is not connected
                }
            };
        }

        public void Stop()
        {
            _timer.Enabled = false;
            _simConnect = null;
        }

        public void StopAndReconnect()
        {
            _simConnect = null;
            _timer.Enabled = true;
        }

        public void RequestData()
        {
            if (_simConnect != null)
                try
                {
                    _simConnect.RequestDataOnSimObjectType(DataRequest.REQUEST_1, SimConnectDefinition.SimConnectDataStruct, 0, SIMCONNECT_SIMOBJECT_TYPE.USER);
                }
                catch (Exception ex)
                {
                    if (ex.Message != "0xC00000B0")
                    {
                        Debug.WriteLine($"SimConnect request data exception: {ex.Message}");
                        StopAndReconnect();
                        OnDisconnected?.Invoke(this, null);
                    }
                }
        }

        public void ReceiveMessage()
        {
            if (_simConnect != null)
                try
                {
                    _simConnect.ReceiveMessage();
                }
                catch (Exception ex)
                {
                    if (ex.Message != "0xC00000B0")
                        Debug.WriteLine($"SimConnect receive message exception: {ex.Message}");
                }
        }

        public void TransmitActionEvent(ActionEvent eventID, uint data)
        {
            if (_simConnect != null)
            {
                try
                {
                    _simConnect.TransmitClientEvent(0U, eventID, data, NotificationGroup.GROUP0, SIMCONNECT_EVENT_FLAG.GROUPID_IS_PRIORITY);
                }
                catch (Exception ex)
                {
                    var eventName = eventID.ToString()[4..];        // trim out KEY_ prefix
                    Debug.WriteLine($"SimConnect transmit event exception: EventName: {eventName} - {ex.Message}");
                }
            }
        }

        public void SetDataObject(SimConnectStruct simConnectStruct)
        {
            if (_simConnect != null)
            {
                try
                {
                    _simConnect.SetDataOnSimObject(SimConnectDefinition.SimConnectDataStruct, SimConnect.SIMCONNECT_OBJECT_ID_USER, SIMCONNECT_DATA_SET_FLAG.DEFAULT, simConnectStruct);
                }
                catch (Exception ex)
                {
                    Debug.WriteLine($"Unable to set SimConnect variable: {ex.Message}");
                }
            }
        }

        private void HandleOnRecvQuit(SimConnect sender, SIMCONNECT_RECV data)
        {
            OnDisconnected?.Invoke(this, null);

            StopAndReconnect();
            // Try to reconnect again
            _timer.Enabled = true;
        }

        private void HandleOnRecvException(SimConnect sender, SIMCONNECT_RECV_EXCEPTION data)
        {
            var exception = (SIMCONNECT_EXCEPTION)data.dwException;

            switch(exception)
            {
                case SIMCONNECT_EXCEPTION.DATA_ERROR:
                case SIMCONNECT_EXCEPTION.NAME_UNRECOGNIZED:
                case SIMCONNECT_EXCEPTION.EVENT_ID_DUPLICATE:
                    return;
                default:
                    Debug.WriteLine($"MSFS Error - {exception}");
                    break;
            }
        }

        private void HandleOnRecvSimobjectDataBytype(SimConnect sender, SIMCONNECT_RECV_SIMOBJECT_DATA_BYTYPE data)
        {
            if (data.dwRequestID == 0)
            {
                try
                {
                    var simConnectStruct = (SimConnectStruct)data.dwData[0];
                    var simConnectStructFields = typeof(SimConnectStruct).GetFields();
                    var simData = new ExpandoObject();

                    var definition = DataDefinition.GetDefinition();
                    int i = 0;
                    foreach (var item in definition)
                    {
                        simData.TryAdd(item.PropName, Convert.ChangeType(simConnectStructFields[i++].GetValue(simConnectStruct), item.ObjectType));
                    }
                    SimData = simData;

                    OnReceivedData?.Invoke(this, new EventArgs<dynamic>(simData));
                }
                catch (Exception ex)
                {
                    Debug.WriteLine($"SimConnect receive data exception: {ex.Message}");
                }
            }
        }

        private void HandleOnReceiveEvent(SimConnect sender, SIMCONNECT_RECV_EVENT data)
        {
            var systemEvent = ((SimConnectSystemEvent)data.uEventID);
            OnReceiveSystemEvent?.Invoke(this, new EventArgs<SimConnectSystemEvent>(systemEvent));
        }
    }
}