//

 // Copyright (C) 2014-2015 Stéphane Lenclud.

 //

 // This file is part of SharpLibHid.

 //

 // SharpDisplayManager is free software: you can redistribute it and/or modify

 // it under the terms of the GNU General Public License as published by

 // the Free Software Foundation, either version 3 of the License, or

 // (at your option) any later version.

 //

 // SharpDisplayManager is distributed in the hope that it will be useful,

 // but WITHOUT ANY WARRANTY; without even the implied warranty of

 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 // GNU General Public License for more details.

 //

 // You should have received a copy of the GNU General Public License

 // along with SharpDisplayManager.  If not, see <http://www.gnu.org/licenses/>.

 //

 using System;

 using System.Windows.Forms;

 using System.Runtime.InteropServices;

 using System.Diagnostics;

 using System.Text;

 using Microsoft.Win32.SafeHandles;

 using SharpLib.Win32;

 using System.Collections.Generic;

 namespace SharpLib.Hid

 {

     /// <summary>

     /// Our HID handler manages raw input registrations, processes WM_INPUT messages and broadcasts HID events in return.

     /// </summary>

     public class Handler : IDisposable

     {

         public delegate void HidEventHandler(object aSender, Event aHidEvent);

         public event HidEventHandler OnHidEvent;

         List<Event> iHidEvents;

         RAWINPUTDEVICE[] iRawInputDevices;

         public bool IsRegistered { get; private set; }

         public bool ManageRepeats { get; private set; }

         public Handler(RAWINPUTDEVICE[] aRawInputDevices, bool aManageRepeats=false)

         {

             iRawInputDevices = aRawInputDevices;

             iHidEvents = new List<Event>();

             IsRegistered = Function.RegisterRawInputDevices(iRawInputDevices, (uint)iRawInputDevices.Length, (uint)Marshal.SizeOf(iRawInputDevices[0]));

             ManageRepeats = aManageRepeats;

         }

         /// <summary>

         /// Will de-register devices.

         /// </summary>

         public void Dispose()

         {

             //Setup device removal

             for (int i=0; i<iRawInputDevices.Length; i++)

             {

                 iRawInputDevices[i].dwFlags = Const.RIDEV_REMOVE;

                 iRawInputDevices[i].hwndTarget = IntPtr.Zero;

             }

             //De-register

             Function.RegisterRawInputDevices(iRawInputDevices, (uint)iRawInputDevices.Length, (uint)Marshal.SizeOf(iRawInputDevices[0]));

             IsRegistered = false;

         }

         /// <summary>

         /// Process a WM_INPUT message.

         /// </summary>

         /// <param name="aMessage"></param>

         public void ProcessInput(ref Message aMessage)

         {

             if (aMessage.Msg != Const.WM_INPUT)

             {

                 //We only process WM_INPUT messages

                 return;

             }

             Event hidEvent = new Event(aMessage, OnHidEventRepeat, ManageRepeats);

             hidEvent.DebugWrite();

             if (!hidEvent.IsValid || !hidEvent.IsGeneric)

             {

                 Debug.WriteLine("Skipping HID message.");

                 return;

             }

             //We want to repeat only a single event at a time.

             //Any other event will interrupt the current repeat.

             if (ManageRepeats)

             {

                 //Discard all outstanding repeats, though we should only ever have only one

                 for (int i = (iHidEvents.Count - 1); i >= 0; i--)

                 {

                         iHidEvents[i].Dispose();

                         iHidEvents.RemoveAt(i);

                 }

                 //Add our newly created event in our repeat list

                 //TODO: instead of a list we could now have a single event since we only support one repeat at a time

                 iHidEvents.Add(hidEvent);

             }

             //Broadcast our events

             OnHidEvent(this, hidEvent);    

         }

         public void OnHidEventRepeat(Event aHidEvent)

         {

             //Broadcast our events

             OnHidEvent(this, aHidEvent);    

         }

     }

 }