text: /**
   * Copyright (c) 2006-2019 LOVE Development Team
   *
   * This software is provided 'as-is', without any express or implied
   * warranty.  In no event will the authors be held liable for any damages
   * arising from the use of this software.
   *
   * Permission is granted to anyone to use this software for any purpose,
   * including commercial applications, and to alter it and redistribute it
   * freely, subject to the following restrictions:
   *
   * 1. The origin of this software must not be misrepresented; you must not
   *    claim that you wrote the original software. If you use this software
   *    in a product, an acknowledgment in the product documentation would be
   *    appreciated but is not required.
   * 2. Altered source versions must be plainly marked as such, and must not be
   *    misrepresented as being the original software.
   * 3. This notice may not be removed or altered from any source distribution.
   **/
  
  #include "common/config.h"
  
  // LOVE
  #include "wrap_Touch.h"
  
  #include "sdl/Touch.h"
  
  namespace love
  {
  namespace touch
  {
  
  #define instance() (Module::getInstance<Touch>(Module::M_TOUCH))
  
  int64 luax_checktouchid(lua_State *L, int idx)
  {
  	if (!lua_islightuserdata(L, idx))
  		return luax_typerror(L, idx, "touch id");
  
  	return (int64) (intptr_t) lua_touserdata(L, 1);
  }
  
  int w_getTouches(lua_State *L)
  {
  	const std::vector<Touch::TouchInfo> &touches = instance()->getTouches();
  
  	lua_createtable(L, (int) touches.size(), 0);
  
  	for (size_t i = 0; i < touches.size(); i++)
  	{
  		// This is a bit hackish and we lose the higher 32 bits of the id on
  		// 32-bit systems, but SDL only ever gives id's that at most use as many
  		// bits as can fit in a pointer (for now.)
  		// We use lightuserdata instead of a lua_Number (double) because doubles
  		// can't represent all possible id values on 64-bit systems.
  		lua_pushlightuserdata(L, (void *) (intptr_t) touches[i].id);
  		lua_rawseti(L, -2, (int) i + 1);
  	}
  
  	return 1;
  }
  
  int w_getPosition(lua_State *L)
  {
  	int64 id = luax_checktouchid(L, 1);
  
  	Touch::TouchInfo touch = {};
  	luax_catchexcept(L, [&]() { touch = instance()->getTouch(id); });
  
  	lua_pushnumber(L, touch.x);
  	lua_pushnumber(L, touch.y);
  
  	return 2;
  }
  
  int w_getPressure(lua_State *L)
  {
  	int64 id = luax_checktouchid(L, 1);
  
  	Touch::TouchInfo touch = {};
  	luax_catchexcept(L, [&](){ touch = instance()->getTouch(id); });
  
  	lua_pushnumber(L, touch.pressure);
  	return 1;
  }
  
  static const luaL_Reg functions[] =
  {
  	{ "getTouches", w_getTouches },
  	{ "getPosition", w_getPosition },
  	{ "getPressure", w_getPressure },
  	{ 0, 0 }
  };
  
  extern "C" int luaopen_love_touch(lua_State *L)
  {
  	Touch *instance = instance();
  	if (instance == nullptr)
  	{
  		luax_catchexcept(L, [&](){ instance = new love::touch::sdl::Touch(); });
  	}
  	else
  		instance->retain();
  
  	WrappedModule w;
  	w.module = instance;
  	w.name = "touch";
  	w.type = &Module::type;
  	w.functions = functions;
  	w.types = nullptr;
  
  	return luax_register_module(L, w);
  }
  
  } // touch
  } // love
  