Program.cs

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//#################################################################################################################################################################################################   
using J2534;
using Microsoft.Owin;
using Microsoft.Owin.Cors;
using Microsoft.Owin.Hosting;
using Newtonsoft.Json.Serialization;
using Owin;
using Swashbuckle.Application;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Net.Http.Formatting;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Web.Http;
using System.Windows.Forms;
namespace AAAAPI
{

    // Token: 0x02000004 RID: 4
    internal static class Program
    {
        [DllImport("kernel32.dll")] private static extern bool AllocConsole();
        [DllImport("kernel32.dll")] private static extern bool FreeConsole();

        [STAThread]
        public static void Main(string[] args)
        {
            // If the project is a Windows app, spawn a console so we can see logs.
            try { AllocConsole(); } catch { /* ignore */ }

            const string baseUrl = "http://localhost:5000";
            const int minSplashMs = 500000; // keep splash visible at least this long
            var splash = default(Splash);
            var splashShown = new ManualResetEvent(false);
            var started = new ManualResetEvent(false);
            var sw = Stopwatch.StartNew();

            // 1) Show splash on its own STA thread
            var splashThread = new Thread(() =>
            {
                try
                {
                    Application.EnableVisualStyles();
                    Application.SetCompatibleTextRenderingDefault(false);
                    splash = new Splash();
                    splashShown.Set();
                    Application.Run(splash); // blocks this UI thread
                }
                catch { /* don't kill process on UI exception */ }
            });
            splashThread.SetApartmentState(ApartmentState.STA);
            splashThread.IsBackground = true;
            splashThread.Start();

            // Wait until splash window actually created (don’t race it)
            splashShown.WaitOne();

            try
            {
                // 2) Start web server
                var webapp = WebApp.Start<Startup>(baseUrl);
                started.Set();

                // Enforce minimum splash duration
                var remain = minSplashMs - (int)sw.ElapsedMilliseconds;
                if (remain > 0) Thread.Sleep(remain);

                // Close splash now that we’re listening
                if (splash != null && !splash.IsDisposed)
                {
                    try { splash.BeginInvoke(new Action(() => splash.Close())); } catch { }
                }

                // 3) Print to console, flush, and stay alive
                Console.Title = "AAAAPI - J2534 HTTP API";
                Console.WriteLine("===============================================");
                Console.WriteLine("The Anonymous Automotive Alliance J2534 HTTP API");
                Console.WriteLine("Listening at {0}  (Swagger: /swagger)", baseUrl);
                Console.WriteLine("Press CTRL + C to exit.");
                Console.WriteLine("===============================================");
                Console.Out.Flush();

                // Keep process alive
                Thread.Sleep(Timeout.Infinite);

                // never hit, but dispose cleanly if you change the loop
                webapp.Dispose();
            }
            catch (Exception ex)
            {
                // If server failed to start, keep splash a moment, then close it and complain loudly
                if (!started.WaitOne(0))
                {
                    // keep splash visible so you actually SEE there was a failure
                    var remain = Math.Max(750, minSplashMs - (int)sw.ElapsedMilliseconds);
                    if (remain > 0) Thread.Sleep(remain);
                    if (splash != null && !splash.IsDisposed)
                    {
                        try { splash.BeginInvoke(new Action(() => splash.Close())); } catch { }
                    }
                }

                var msg =
                    "Web server failed to start.\r\n\r\n" +
                    ex.GetType().FullName + ":\r\n" +
                    ex.Message + "\r\n\r\n" +
                    "Common causes:\r\n" +
                    "  • Port in use\r\n" +
                    "  • URL ACL not reserved (http.sys permissions)\r\n" +
                    "  • Missing packages/references\r\n";

                try { MessageBox.Show(msg, "AAAAPI", MessageBoxButtons.OK, MessageBoxIcon.Error); } catch { }
                Console.Error.WriteLine(msg);
                Console.Error.WriteLine(ex);
                Console.Error.Flush();

                // keep the console open so you can read it
                Console.WriteLine("Press ENTER to quit...");
                Console.ReadLine();

                try { FreeConsole(); } catch { }
            }
        }
    }
    public class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            app.UseCors(CorsOptions.AllowAll);

            var config = new HttpConfiguration();

            // Attribute routing
            config.MapHttpAttributeRoutes();

            // Conventional routing
            config.Routes.MapHttpRoute(
                name: "DefaultApi",
                routeTemplate: "{controller}/{action}"
            );

            // JSON formatting (Newtonsoft)
            var json = config.Formatters.JsonFormatter;
            json.SerializerSettings.Formatting = Newtonsoft.Json.Formatting.Indented;
            json.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();

            // Swagger (Swashbuckle 5.x for Web API)
            config.EnableSwagger(c =>
            {
                c.SingleApiVersion("v1", "J2534 HTTP API");
                c.PrettyPrint();
            })
            .EnableSwaggerUi();

            // Register single host (simple static DI)
            J2534Service.Instance = new J2534Host();

            app.UseWebApi(config);
        }
    }

    // Simple static locator for our host (keeps it dead simple)
    public static class J2534Service
    {
        public static J2534Host Instance;
    }

    // ---------------- DTOs (plain classes; no records, no nullable refs) ----------------
    public class LoadReq
    {
        public J2534Device Device { get; set; }
    }

    public class ConnectReq
    {
        public ProtocolID Protocol { get; set; } = ProtocolID.CAN;
        public ConnectFlag Flags { get; set; } = ConnectFlag.NONE;
        public BaudRate Baud { get; set; } = BaudRate.CAN_500000;
    }

    public class WriteReq
    {
        public ProtocolID Protocol { get; set; }
        public TxFlag TxFlags { get; set; }
        public string HexData { get; set; } // "02 10 01"
        public int TimeoutMs { get; set; } = 100;
    }

    public class ReadReq
    {
        public int NumMsgs { get; set; } = 50;
        public int TimeoutMs { get; set; } = 50;
        public bool UntilTimeout { get; set; } = true;
    }

    public class ConfigReq
    {
        public Dictionary<ConfigParameter, ushort> Values { get; set; }
    }

    public class GetConfigReq
    {
        public List<ConfigParameter> Keys { get; set; }
    }

    public class StartFilterReq
    {
        public FilterType Type { get; set; }
        public string MaskHex { get; set; }
        public string PatternHex { get; set; }
        public string FlowHex { get; set; }
    }

    public class StopFilterReq
    {
        public int FilterId { get; set; }
    }

    // ---------------- Controller (Web API classic) ----------------
    [RoutePrefix("j2534")]
    public class J2534Controller : ApiController
    {
        private J2534Host Host { get { return J2534Service.Instance; } }

        [HttpGet, Route("state")]
        public IHttpActionResult State() { return Ok(Host.Summary()); }

        [HttpPost, Route("load")]
        public IHttpActionResult Load([FromBody] LoadReq req)
        {
            Host.Load(req.Device);
            return Ok(Host.Summary());
        }

        [HttpPost, Route("free")]
        public IHttpActionResult Free() { Host.Free(); return Ok(Host.Summary()); }

        [HttpPost, Route("open")]
        public IHttpActionResult Open() { Host.Open(); return Ok(Host.Summary()); }

        [HttpPost, Route("close")]
        public IHttpActionResult Close() { Host.Close(); return Ok(Host.Summary()); }

        [HttpPost, Route("connect")]
        public IHttpActionResult Connect([FromBody] ConnectReq req) { Host.Connect(req); return Ok(Host.Summary()); }

        [HttpPost, Route("disconnect")]
        public IHttpActionResult Disconnect() { Host.Disconnect(); return Ok(Host.Summary()); }

        [HttpPost, Route("write")]
        public IHttpActionResult Write([FromBody] WriteReq req) { var sent = Host.Write(req); return Ok(new { sent = sent }); }

        [HttpPost, Route("read")]
        public IHttpActionResult Read([FromBody] ReadReq req) { var frames = Host.Read(req); return Ok(new { frames = frames }); }

        [HttpPost, Route("set-config")]
        public IHttpActionResult SetConfig([FromBody] ConfigReq req) { Host.SetConfig(req); return Ok(Host.Summary()); }

        [HttpPost, Route("get-config")]
        public IHttpActionResult GetConfig([FromBody] GetConfigReq req) { var cfg = Host.GetConfig(req); return Ok(cfg); }

        [HttpPost, Route("filters/clear")]
        public IHttpActionResult ClearFilters() { Host.ClearFilters(); return Ok(Host.Summary()); }

        [HttpPost, Route("filters/start")]
        public IHttpActionResult StartFilter([FromBody] StartFilterReq req) { var id = Host.StartFilter(req); return Ok(new { filterId = id }); }

        [HttpPost, Route("filters/stop")]
        public IHttpActionResult StopFilter([FromBody] StopFilterReq req) { Host.StopFilter(req.FilterId); return Ok(Host.Summary()); }

        [HttpPost, Route("clear-tx")]
        public IHttpActionResult ClearTx() { Host.ClearTx(); return Ok(); }

        [HttpPost, Route("clear-rx")]
        public IHttpActionResult ClearRx() { Host.ClearRx(); return Ok(); }

        [HttpPost, Route("clear-periodic")]
        public IHttpActionResult ClearPeriodic() { Host.ClearPeriodic(); return Ok(); }

        [HttpGet, Route("vbatt")]
        public IHttpActionResult VBatt() { var mv = Host.ReadVBattMilliVolts(); return Ok(new { millivolts = mv, volts = mv / 1000.0 }); }

        [HttpGet, Route("vprog")]
        public IHttpActionResult VProg() { var mv = Host.ReadVProgMilliVolts(); return Ok(new { millivolts = mv, volts = mv / 1000.0 }); }
    }

    // ---------------- Host (no nullable refs, C#7.3-friendly) ----------------
    public class J2534Host
    {
        private readonly IJ2534Extended _api = new J2534FunctionsExtended();
        private J2534Device _dev;
        private uint _deviceId;
        private uint _channelId;
        private bool _dllLoaded;
        private bool _opened;
        private bool _connected;

        public object Summary()
        {
            return new
            {
                dllLoaded = _dllLoaded,
                opened = _opened,
                connected = _connected,
                deviceId = _deviceId,
                channelId = _channelId,
                device = _dev == null ? null : new { _dev.Name, _dev.Vendor, _dev.FunctionLibrary }
            };
        }

        public void Load(J2534Device device)
        {
            if (device == null) throw new ArgumentNullException("device");
            _dev = device;
            _dllLoaded = _api.LoadLibrary(_dev);
            if (!_dllLoaded) throw new Exception("Failed to load J2534 DLL: " + device.FunctionLibrary);
        }

        public void Free()
        {
            _api.FreeLibrary();
            _dllLoaded = false;
        }

        public void Open()
        {
            EnsureDll();
            var err = _api.PassThruOpen(IntPtr.Zero, ref _deviceId);
            ThrowIfErr(err, "PassThruOpen");
            _opened = true;
        }

        public void Close()
        {
            if (_opened)
            {
                var err = _api.PassThruClose(_deviceId);
                ThrowIfErr(err, "PassThruClose");
            }
            _opened = false;
            _deviceId = 0;
        }

        public void Connect(ConnectReq req)
        {
            EnsureOpen();
            var err = _api.PassThruConnect(_deviceId, req.Protocol, req.Flags, req.Baud, ref _channelId);
            ThrowIfErr(err, "PassThruConnect");
            _connected = true;
        }

        public void Disconnect()
        {
            if (_connected)
            {
                var err = _api.PassThruDisconnect((int)_channelId);
                ThrowIfErr(err, "PassThruDisconnect");
            }
            _connected = false;
            _channelId = 0;
        }

        public int Write(WriteReq req)
        {
            EnsureConnected();
            var bytes = HexToBytes(req.HexData);
            var msg = new PassThruMsg(req.Protocol, req.TxFlags, bytes);
            var p = msg.ToIntPtr();
            try
            {
                int count = 1;
                var err = _api.PassThruWriteMsgs((int)_channelId, p, ref count, req.TimeoutMs);
                ThrowIfErr(err, "PassThruWriteMsgs");
                return count;
            }
            finally { Marshal.FreeHGlobal(p); }
        }

        public List<string> Read(ReadReq req)
        {
            EnsureConnected();
            List<PassThruMsg> msgs;
            var ok = _api.ReadAllMessages((int)_channelId, req.NumMsgs, req.TimeoutMs, out msgs, req.UntilTimeout);
            if (ok != J2534Err.STATUS_NOERROR && ok != J2534Err.ERR_TIMEOUT)
                ThrowIfErr(ok, "ReadAllMessages");

            var frames = new List<string>(msgs.Count);
            for (int i = 0; i < msgs.Count; i++)
                frames.Add(BitConverter.ToString(msgs[i].GetBytes()).Replace("-", " "));
            return frames;
        }

        public void SetConfig(ConfigReq req)
        {
            EnsureConnected();
            var list = new List<SConfig>();
            foreach (var kv in req.Values)
                list.Add(new SConfig { Parameter = kv.Key, Value = kv.Value });
            var err = _api.SetConfig((int)_channelId, ref list);
            ThrowIfErr(err, "SET_CONFIG");
        }

        public Dictionary<ConfigParameter, ushort> GetConfig(GetConfigReq req)
        {
            EnsureConnected();
            var list = new List<SConfig>();
            foreach (var key in req.Keys)
                list.Add(new SConfig { Parameter = key, Value = 0 });
            var err = _api.GetConfig((int)_channelId, ref list);
            ThrowIfErr(err, "GET_CONFIG");
            var result = new Dictionary<ConfigParameter, ushort>();
            for (int i = 0; i < list.Count; i++) result[list[i].Parameter] = list[i].Value;
            return result;
        }

        public void ClearFilters()
        {
            EnsureConnected();
            var err = _api.ClearMsgFilters((int)_channelId);
            ThrowIfErr(err, "CLEAR_MSG_FILTERS");
        }

        public int StartFilter(StartFilterReq req)
        {
            EnsureConnected();
            IntPtr mask = IntPtr.Zero, pattern = IntPtr.Zero, flow = IntPtr.Zero;
            int filterId = 0;
            try
            {
                if (!string.IsNullOrEmpty(req.MaskHex))
                    mask = BuildMsgPtr(HexToBytes(req.MaskHex), ProtocolID.CAN);
                if (!string.IsNullOrEmpty(req.PatternHex))
                    pattern = BuildMsgPtr(HexToBytes(req.PatternHex), ProtocolID.CAN);
                if (!string.IsNullOrEmpty(req.FlowHex))
                    flow = BuildMsgPtr(HexToBytes(req.FlowHex), ProtocolID.CAN);

                var err = _api.PassThruStartMsgFilter((int)_channelId, req.Type, mask, pattern, flow, ref filterId);
                ThrowIfErr(err, "PassThruStartMsgFilter");
                return filterId;
            }
            finally
            {
                if (mask != IntPtr.Zero) Marshal.FreeHGlobal(mask);
                if (pattern != IntPtr.Zero) Marshal.FreeHGlobal(pattern);
                if (flow != IntPtr.Zero) Marshal.FreeHGlobal(flow);
            }
        }

        public void StopFilter(int filterId)
        {
            EnsureConnected();
            var err = _api.PassThruStopMsgFilter((int)_channelId, filterId);
            ThrowIfErr(err, "PassThruStopMsgFilter");
        }

        public void ClearTx() { EnsureConnected(); ThrowIfErr(_api.ClearTxBuffer((int)_channelId), "CLEAR_TX_BUFFER"); }
        public void ClearRx() { EnsureConnected(); ThrowIfErr(_api.ClearRxBuffer((int)_channelId), "CLEAR_RX_BUFFER"); }
        public void ClearPeriodic() { EnsureConnected(); ThrowIfErr(_api.ClearPeriodicMsgs((int)_channelId), "CLEAR_PERIODIC_MSGS"); }

        public int ReadVBattMilliVolts()
        {
            EnsureOpen();
            int v = 0;
            var err = _api.ReadBatteryVoltage((int)_deviceId, ref v);
            ThrowIfErr(err, "READ_VBATT");
            return v;
        }

        public int ReadVProgMilliVolts()
        {
            EnsureOpen();
            int v = 0;
            var err = _api.ReadProgrammingVoltage((int)_deviceId, ref v);
            ThrowIfErr(err, "READ_PROG_VOLTAGE");
            return v;
        }

        // Helpers
        private void EnsureDll()
        {
            if (!_dllLoaded) throw new InvalidOperationException("J2534 DLL not loaded. POST /j2534/load first.");
        }
        private void EnsureOpen()
        {
            EnsureDll();
            if (!_opened) throw new InvalidOperationException("Device not opened. POST /j2534/open first.");
        }
        private void EnsureConnected()
        {
            EnsureOpen();
            if (!_connected) throw new InvalidOperationException("Not connected. POST /j2534/connect first.");
        }
        private static void ThrowIfErr(J2534Err err, string op)
        {
            if (err != J2534Err.STATUS_NOERROR)
                throw new InvalidOperationException(op + " failed: " + err);
        }

        private static byte[] HexToBytes(string hexish)
        {
            if (string.IsNullOrWhiteSpace(hexish)) return new byte[0];
            var sb = new StringBuilder();
            var s = hexish.Trim();
            for (int i = 0; i < s.Length; i++)
            {
                char ch = s[i];
                if (Uri.IsHexDigit(ch)) sb.Append(ch);
            }
            string clean = sb.ToString();
            if (clean.Length % 2 != 0) throw new ArgumentException("Hex length must be even.");
            var bytes = new byte[clean.Length / 2];
            for (int i = 0; i < bytes.Length; i++)
                bytes[i] = Convert.ToByte(clean.Substring(i * 2, 2), 16);
            return bytes;
        }

        private static IntPtr BuildMsgPtr(byte[] payload, ProtocolID proto)
        {
            var msg = new PassThruMsg(proto, TxFlag.NONE, payload);
            return msg.ToIntPtr();
        }
    }
}