#pragma once

#ifndef WM_GESTURE

#define WM_GESTURE                      0x0119
#define WM_GESTURENOTIFY                0x011A


DECLARE_HANDLE(HGESTUREINFO);


/*
 * Gesture flags - GESTUREINFO.dwFlags
 */
#define GF_BEGIN                        0x00000001
#define GF_INERTIA                      0x00000002
#define GF_END                          0x00000004

/*
 * Gesture IDs
 */
#define GID_BEGIN                       1
#define GID_END                         2
#define GID_ZOOM                        3
#define GID_PAN                         4
#define GID_ROTATE                      5
#define GID_TWOFINGERTAP                6
#define GID_PRESSANDTAP                 7
#define GID_ROLLOVER                    GID_PRESSANDTAP

/*
 * Gesture information structure
 *   - Pass the HGESTUREINFO received in the WM_GESTURE message lParam into the
 *     GetGestureInfo function to retrieve this information.
 *   - If cbExtraArgs is non-zero, pass the HGESTUREINFO received in the WM_GESTURE
 *     message lParam into the GetGestureExtraArgs function to retrieve extended
 *     argument information.
 */
typedef struct tagGESTUREINFO {
    UINT cbSize;                    // size, in bytes, of this structure (including variable length Args field)
    DWORD dwFlags;                  // see GF_* flags
    DWORD dwID;                     // gesture ID, see GID_* defines
    HWND hwndTarget;                // handle to window targeted by this gesture
    POINTS ptsLocation;             // current location of this gesture
    DWORD dwInstanceID;             // internally used
    DWORD dwSequenceID;             // internally used
    ULONGLONG ullArguments;         // arguments for gestures whose arguments fit in 8 BYTES
    UINT cbExtraArgs;               // size, in bytes, of extra arguments, if any, that accompany this gesture
} GESTUREINFO, *PGESTUREINFO;
typedef GESTUREINFO const * PCGESTUREINFO;


/*
 * Gesture notification structure
 *   - The WM_GESTURENOTIFY message lParam contains a pointer to this structure.
 *   - The WM_GESTURENOTIFY message notifies a window that gesture recognition is
 *     in progress and a gesture will be generated if one is recognized under the
 *     current gesture settings.
 */
typedef struct tagGESTURENOTIFYSTRUCT {
    UINT cbSize;                    // size, in bytes, of this structure
    DWORD dwFlags;                  // unused
    HWND hwndTarget;                // handle to window targeted by the gesture
    POINTS ptsLocation;             // starting location
    DWORD dwInstanceID;             // internally used
} GESTURENOTIFYSTRUCT, *PGESTURENOTIFYSTRUCT;

/*
 * Gesture argument helpers
 *   - Angle should be a double in the range of -2pi to +2pi
 *   - Argument should be an unsigned 16-bit value
 */
#define GID_ROTATE_ANGLE_TO_ARGUMENT(_arg_)     ((USHORT)((((_arg_) + 2.0 * 3.14159265) / (4.0 * 3.14159265)) * 65535.0))
#define GID_ROTATE_ANGLE_FROM_ARGUMENT(_arg_)   ((((double)(_arg_) / 65535.0) * 4.0 * 3.14159265) - 2.0 * 3.14159265)

/*
 * Gesture information retrieval
 *   - HGESTUREINFO is received by a window in the lParam of a WM_GESTURE message.
 */
WINUSERAPI
BOOL
WINAPI
GetGestureInfo(
    __in HGESTUREINFO hGestureInfo,
    __out PGESTUREINFO pGestureInfo);



/*
 * Gesture extra arguments retrieval
 *   - HGESTUREINFO is received by a window in the lParam of a WM_GESTURE message.
 *   - Size, in bytes, of the extra argument data is available in the cbExtraArgs
 *     field of the GESTUREINFO structure retrieved using the GetGestureInfo function.
 */
WINUSERAPI
BOOL
WINAPI
GetGestureExtraArgs(
    __in HGESTUREINFO hGestureInfo,
    __in UINT cbExtraArgs,
    __out_bcount(cbExtraArgs) PBYTE pExtraArgs);

/*
 * Gesture information handle management
 *   - If an application processes the WM_GESTURE message, then once it is done
 *     with the associated HGESTUREINFO, the application is responsible for
 *     closing the handle using this function. Failure to do so may result in
 *     process memory leaks.
 *   - If the message is instead passed to DefWindowProc, or is forwarded using
 *     one of the PostMessage or SendMessage class of API functions, the handle
 *     is transfered with the message and need not be closed by the application.
 */
WINUSERAPI
BOOL
WINAPI
CloseGestureInfoHandle(
    __in HGESTUREINFO hGestureInfo);


/*
 * Gesture configuration structure
 *   - Used in SetGestureConfig and GetGestureConfig
 *   - Note that any setting not included in either GESTURECONFIG.dwWant or
 *     GESTURECONFIG.dwBlock will use the parent window's preferences or
 *     system defaults.
 */
typedef struct tagGESTURECONFIG {
    DWORD dwID;                     // gesture ID
    DWORD dwWant;                   // settings related to gesture ID that are to be turned on
    DWORD dwBlock;                  // settings related to gesture ID that are to be turned off
} GESTURECONFIG, *PGESTURECONFIG;

/*
 * Gesture configuration flags - GESTURECONFIG.dwWant or GESTURECONFIG.dwBlock
 */

/*
 * Common gesture configuration flags - set GESTURECONFIG.dwID to zero
 */
#define GC_ALLGESTURES                              0x00000001

/*
 * Zoom gesture configuration flags - set GESTURECONFIG.dwID to GID_ZOOM
 */
#define GC_ZOOM                                     0x00000001

/*
 * Pan gesture configuration flags - set GESTURECONFIG.dwID to GID_PAN
 */
#define GC_PAN                                      0x00000001
#define GC_PAN_WITH_SINGLE_FINGER_VERTICALLY        0x00000002
#define GC_PAN_WITH_SINGLE_FINGER_HORIZONTALLY      0x00000004
#define GC_PAN_WITH_GUTTER                          0x00000008
#define GC_PAN_WITH_INERTIA                         0x00000010

/*
 * Rotate gesture configuration flags - set GESTURECONFIG.dwID to GID_ROTATE
 */
#define GC_ROTATE                                   0x00000001

/*
 * Two finger tap gesture configuration flags - set GESTURECONFIG.dwID to GID_TWOFINGERTAP
 */
#define GC_TWOFINGERTAP                             0x00000001

/*
 * PressAndTap gesture configuration flags - set GESTURECONFIG.dwID to GID_PRESSANDTAP
 */
#define GC_PRESSANDTAP                              0x00000001
#define GC_ROLLOVER                                 GC_PRESSANDTAP

#define GESTURECONFIGMAXCOUNT           256             // Maximum number of gestures that can be included
                                                        // in a single call to SetGestureConfig / GetGestureConfig

WINUSERAPI
BOOL
WINAPI
SetGestureConfig(
    __in HWND hwnd,                                     // window for which configuration is specified
    __in DWORD dwReserved,                              // reserved, must be 0
    __in UINT cIDs,                                     // count of GESTURECONFIG structures
    __in_ecount(cIDs) PGESTURECONFIG pGestureConfig,    // array of GESTURECONFIG structures, dwIDs will be processed in the
                                                        // order specified and repeated occurances will overwrite previous ones
    __in UINT cbSize);                                  // sizeof(GESTURECONFIG)




#define GCF_INCLUDE_ANCESTORS           0x00000001      // If specified, GetGestureConfig returns consolidated configuration
                                                        // for the specified window and it's parent window chain

WINUSERAPI
BOOL
WINAPI
GetGestureConfig(
    __in HWND hwnd,                                     // window for which configuration is required
    __in DWORD dwReserved,                              // reserved, must be 0
    __in DWORD dwFlags,                                 // see GCF_* flags
    __in PUINT pcIDs,                                   // *pcIDs contains the size, in number of GESTURECONFIG structures,
                                                        // of the buffer pointed to by pGestureConfig
    __inout_ecount(*pcIDs) PGESTURECONFIG pGestureConfig,
                                                        // pointer to buffer to receive the returned array of GESTURECONFIG structures
    __in UINT cbSize);                                  // sizeof(GESTURECONFIG)



typedef BOOL
(WINAPI *pGetGestureInfo_t)(
	__in HGESTUREINFO hGestureInfo,
	__out PGESTUREINFO pGestureInfo);

typedef BOOL
(WINAPI * pCloseGestureInfoHandle_t)(
	__in HGESTUREINFO hGestureInfo);

typedef BOOL
(WINAPI * pSetGestureConfig_t) (
	__in HWND hwnd,                                     // window for which configuration is specified
	__in DWORD dwReserved,                              // reserved, must be 0
	__in UINT cIDs,                                     // count of GESTURECONFIG structures
	__in_ecount(cIDs) PGESTURECONFIG pGestureConfig,    // array of GESTURECONFIG structures, dwIDs will be processed in the
														// order specified and repeated occurances will overwrite previous ones
	__in UINT cbSize);                                  // sizeof(GESTURECONFIG)

class CGestureAPI {
public:
	CGestureAPI() {
		HMODULE dll = GetModuleHandle(_T("user32.dll"));

		Bind(GetGestureInfo, dll, "GetGestureInfo");
		Bind(CloseGestureInfoHandle, dll, "CloseGestureInfoHandle");
		Bind(SetGestureConfig, dll, "SetGestureConfig");
	}

	bool IsAvailable() {
		return this->GetGestureInfo != NULL;
	}

	pGetGestureInfo_t GetGestureInfo;
	pCloseGestureInfoHandle_t CloseGestureInfoHandle;
	pSetGestureConfig_t SetGestureConfig;
private:
	template<typename func_t> static void Bind(func_t & f, HMODULE dll, const char * name) {
		f = reinterpret_cast<func_t>(GetProcAddress(dll, name));
	}
};
#else

class CGestureAPI {
public:
	inline static bool IsAvailable() { return true; }
	inline static BOOL GetGestureInfo(HGESTUREINFO hGestureInfo, PGESTUREINFO pGestureInfo) {
		return ::GetGestureInfo(hGestureInfo, pGestureInfo);
	}
	inline static BOOL CloseGestureInfoHandle(HGESTUREINFO hGestureInfo) {
		return ::CloseGestureInfoHandle(hGestureInfo);
	}

	inline static BOOL SetGestureConfig(HWND hwnd, DWORD dwReserved, UINT cIDs, PGESTURECONFIG pGestureConfig, UINT cbSize) {
		return ::SetGestureConfig(hwnd, dwReserved, cIDs, pGestureConfig, cbSize);
	}
};
#endif