//   BlitzUtility - Expanding the normal Blitz functionality.
//   Copyright (C) 2015 Xaymar (Michael Fabian Dirks)
//
//   This program is free software: you can redistribute it and/or modify
//   it under the terms of the GNU Lesser General Public License as
//   published by the Free Software Foundation, either version 3 of the
//   License, or (at your option) any later version.
//
//   This program 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 Lesser General Public License
//   along with this program.  If not, see <http://www.gnu.org/licenses/>.

#pragma once
#include "WindowMessageHandler.h"

std::list<WindowUserData>* WindowMessageHandler_List;

void BU_WindowMessageHandler_OnProcessAttach() {
   WindowMessageHandler_List = new std::list<WindowUserData>();
}

void BU_WindowMessageHandler_OnProcessDetach() {
   for (auto iterator = WindowMessageHandler_List->begin(), end = WindowMessageHandler_List->end(); iterator != end; iterator++) {
      BU_WindowMessageHandler_Uninstall(iterator->hwnd);
   }

   WindowMessageHandler_List->clear();
   delete WindowMessageHandler_List;
}

LRESULT CALLBACK BU_WindowMessageHandler_Procedure(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
   WindowUserData* UserData = (WindowUserData*)GetWindowLong(hwnd, GWL_USERDATA);
   if (UserData) {
      switch (uMsg) {
         case WM_SIZE:
            UserData->WindowWasResized = true;
            UserData->WindowClientWidth = lParam & 0xFFFF;
            UserData->WindowClientHeight = lParam & 0xFFFF0000 >> 16;

            return CallWindowProc(UserData->oWindowProcedure, hwnd, uMsg, wParam, lParam);
            break;
         
         case WM_CLOSE:
            UserData->DestroyCount++;
            return false;

         case WM_DESTROY:
            UserData->CloseCount++;
            return false;

         default:
            return CallWindowProc(UserData->oWindowProcedure, hwnd, uMsg, wParam, lParam);
      }
   } else {
      return DefWindowProc(hwnd, uMsg, wParam, lParam);
   }
}

DLL_FUNCTION(void) BU_WindowMessageHandler_Install(HWND hwnd)
{
   WindowUserData* UserData = new WindowUserData;
   ZeroMemory(UserData, sizeof(UserData));
   UserData->oWindowProcedure = (WNDPROC)SetWindowLong(hwnd, GWL_WNDPROC, (LONG)&BU_WindowMessageHandler_Procedure);
   UserData->oUserData = SetWindowLong(hwnd, GWL_USERDATA, (LONG)UserData);
}

DLL_FUNCTION(void) BU_WindowMessageHandler_Uninstall(HWND hwnd)
{
   WindowUserData* UserData = (WindowUserData*)GetWindowLong(hwnd, GWL_USERDATA);
   if (UserData) {
      SetWindowLong(hwnd, GWL_USERDATA, UserData->oUserData);
      SetWindowLong(hwnd, GWL_WNDPROC, (LONG)(UserData->oWindowProcedure));
      delete UserData;
   }
}

DLL_FUNCTION(uint32_t) BU_WindowMessageHandler_Message_Resize(HWND hwnd, LPPOINT point)
{
   WindowUserData* UserData = (WindowUserData*)GetWindowLong(hwnd, GWL_USERDATA);
   if (UserData) {
      int toReturn = UserData->WindowWasResized;
      point->x = UserData->WindowClientWidth;
      point->y = UserData->WindowClientHeight;
      UserData->WindowWasResized = false;
      return toReturn;
   }
   return FALSE;
}

DLL_FUNCTION(uint32_t) BU_WindowMessageHandler_Message_Destroy(HWND hwnd)
{
   WindowUserData* UserData = (WindowUserData*)GetWindowLong(hwnd, GWL_USERDATA);
   if (UserData) {
      int toReturn = UserData->DestroyCount;
      UserData->DestroyCount = 0;
      return toReturn;
   }
   return 0;
}

DLL_FUNCTION(uint32_t) BU_WindowMessageHandler_Message_Close(HWND hwnd)
{
   if (hwnd) {
      WindowUserData* UserData = (WindowUserData*)GetWindowLong(hwnd, GWL_USERDATA);
      if (UserData) {
         int toReturn = UserData->CloseCount;
         UserData->CloseCount = 0;
         return toReturn;
      }
   }
   return 0;
}

Global WindowMessageHandler_p = 0
Global OriginalWindowProcedure = 0
Function WindowMessageHandler(hwnd, uMsg, wParam, lParam)
    If WindowMessageHandler_p = 0 Then
         WindowMessageHandler_p = BP_GetFunctionPointer()
    EndIf
   
    Select uMsg ; Nachrichten Typ hier, WM_USER bis 0x7FFF möglich. RegisterWindowMessage liefert den wert der hier abgefragt werden muss
        Default
            BP_CallFunctionVIIII(OriginalWindowProcedure, hwnd, uMsg, wParam, lParam)
    End Select
End Function:WindowMessageHandler(0,0,0,0)

OriginalWindowProcedure = SetWindowLong(SystemProperty("AppHwnd"), GWL_WNDPROC, WindowMessageHandler_p );