/*

     SDL - Simple DirectMedia Layer

     Copyright (C) 1997-2006 Sam Lantinga

     This library 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 2.1 of the License, or (at your option) any later version.

     This library 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

     Lesser General Public License for more details.

     You should have received a copy of the GNU Lesser General Public

     License along with this library; if not, write to the Free Software

     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

     Sam Lantinga

     slouken@libsdl.org

 */

 #include "SDL_config.h"

 /* General mouse handling code for SDL */

 #include "SDL_events.h"

 #include "SDL_events_c.h"

 #include "../video/SDL_cursor_c.h"

 #include "../video/SDL_sysvideo.h"

 /* These are static for our mouse handling code */

 static Sint16 SDL_MouseX = 0;

 static Sint16 SDL_MouseY = 0;

 static Sint16 SDL_DeltaX = 0;

 static Sint16 SDL_DeltaY = 0;

 static Uint8  SDL_ButtonState = 0;

 /* Public functions */

 int SDL_MouseInit(void)

 {

 	/* The mouse is at (0,0) */

 	SDL_MouseX = 0;

 	SDL_MouseY = 0;

 	SDL_DeltaX = 0;

 	SDL_DeltaY = 0;

 	SDL_ButtonState = 0;

 	/* That's it! */

 	return(0);

 }

 void SDL_MouseQuit(void)

 {

 }

 /* We lost the mouse, so post button up messages for all pressed buttons */

 void SDL_ResetMouse(void)

 {

 	Uint8 i;

 	for ( i = 0; i < sizeof(SDL_ButtonState)*8; ++i ) {

 		if ( SDL_ButtonState & SDL_BUTTON(i) ) {

 			SDL_PrivateMouseButton(SDL_RELEASED, i, 0, 0);

 		}

 	}

 }

 Uint8 SDL_GetMouseState (int *x, int *y)

 {

 	if ( x ) {

 		*x = SDL_MouseX;

 	}

 	if ( y ) {

 		*y = SDL_MouseY;

 	}

 	return(SDL_ButtonState);

 }

 Uint8 SDL_GetRelativeMouseState (int *x, int *y)

 {

 	if ( x )

 		*x = SDL_DeltaX;

 	if ( y )

 		*y = SDL_DeltaY;

 	SDL_DeltaX = 0;

 	SDL_DeltaY = 0;

 	return(SDL_ButtonState);

 }

 static void ClipOffset(Sint16 *x, Sint16 *y)

 {

 	/* This clips absolute mouse coordinates when the apparent

 	   display surface is smaller than the real display surface.

 	 */

 	if ( SDL_VideoSurface->offset ) {

 		*y -= SDL_VideoSurface->offset/SDL_VideoSurface->pitch;

 		*x -= (SDL_VideoSurface->offset%SDL_VideoSurface->pitch)/

 				SDL_VideoSurface->format->BytesPerPixel;

 	}

 }

 /* These are global for SDL_eventloop.c */

 int SDL_PrivateMouseMotion(Uint8 buttonstate, int relative, Sint16 x, Sint16 y)

 {

 	int posted;

 	Uint16 X, Y;

 	Sint16 Xrel;

 	Sint16 Yrel;

 	/* Don't handle mouse motion if there's no cursor surface */

 	if ( SDL_VideoSurface == NULL ) {

 		return(0);

 	}

 	/* Default buttonstate is the current one */

 	if ( ! buttonstate ) {

 		buttonstate = SDL_ButtonState;

 	}

 	Xrel = x;

 	Yrel = y;

 	if ( relative ) {

 		/* Push the cursor around */

 		x = (SDL_MouseX+x);

 		y = (SDL_MouseY+y);

 	} else {

 		/* Do we need to clip {x,y} ? */

 		ClipOffset(&x, &y);

 	}

 	/* Mouse coordinates range from 0 - width-1 and 0 - height-1 */

 	if ( x < 0 )

 		X = 0;

 	else

 	if ( x >= SDL_VideoSurface->w )

 		X = SDL_VideoSurface->w-1;

 	else

 		X = (Uint16)x;

 	if ( y < 0 )

 		Y = 0;

 	else

 	if ( y >= SDL_VideoSurface->h )

 		Y = SDL_VideoSurface->h-1;

 	else

 		Y = (Uint16)y;

 	/* If not relative mode, generate relative motion from clamped X/Y.

 	   This prevents lots of extraneous large delta relative motion when

 	   the screen is windowed mode and the mouse is outside the window.

 	*/

 	if ( ! relative ) {

 		Xrel = X-SDL_MouseX;

 		Yrel = Y-SDL_MouseY;

 	}

 	/* Drop events that don't change state */

 	if ( ! Xrel && ! Yrel ) {

 #if 0

 printf("Mouse event didn't change state - dropped!\n");

 #endif

 		return(0);

 	}

 	/* Update internal mouse state */

 	SDL_ButtonState = buttonstate;

 	SDL_MouseX = X;

 	SDL_MouseY = Y;

 	SDL_DeltaX += Xrel;

 	SDL_DeltaY += Yrel;

         SDL_MoveCursor(SDL_MouseX, SDL_MouseY);

 	/* Post the event, if desired */

 	posted = 0;

 	if ( SDL_ProcessEvents[SDL_MOUSEMOTION] == SDL_ENABLE ) {

 		SDL_Event event;

 		SDL_memset(&event, 0, sizeof(event));

 		event.type = SDL_MOUSEMOTION;

 		event.motion.state = buttonstate;

 		event.motion.x = X;

 		event.motion.y = Y;

 		event.motion.xrel = Xrel;

 		event.motion.yrel = Yrel;

 		if ( (SDL_EventOK == NULL) || (*SDL_EventOK)(&event) ) {

 			posted = 1;

 			SDL_PushEvent(&event);

 		}

 	}

 	return(posted);

 }

 int SDL_PrivateMouseButton(Uint8 state, Uint8 button, Sint16 x, Sint16 y)

 {

 	SDL_Event event;

 	int posted;

 	int move_mouse;

 	Uint8 buttonstate;

 	SDL_memset(&event, 0, sizeof(event));

 	/* Check parameters */

 	if ( x || y ) {

 		ClipOffset(&x, &y);

 		move_mouse = 1;

 		/* Mouse coordinates range from 0 - width-1 and 0 - height-1 */

 		if ( x < 0 )

 			x = 0;

 		else

 		if ( x >= SDL_VideoSurface->w )

 			x = SDL_VideoSurface->w-1;

 		if ( y < 0 )

 			y = 0;

 		else

 		if ( y >= SDL_VideoSurface->h )

 			y = SDL_VideoSurface->h-1;

 	} else {

 		move_mouse = 0;

 	}

 	if ( ! x )

 		x = SDL_MouseX;

 	if ( ! y )

 		y = SDL_MouseY;

 	/* Figure out which event to perform */

 	buttonstate = SDL_ButtonState;

 	switch ( state ) {

 		case SDL_PRESSED:

 			event.type = SDL_MOUSEBUTTONDOWN;

 			buttonstate |= SDL_BUTTON(button);

 			break;

 		case SDL_RELEASED:

 			event.type = SDL_MOUSEBUTTONUP;

 			buttonstate &= ~SDL_BUTTON(button);

 			break;

 		default:

 			/* Invalid state -- bail */

 			return(0);

 	}

 	/* Update internal mouse state */

 	SDL_ButtonState = buttonstate;

 	if ( move_mouse ) {

 		SDL_MouseX = x;

 		SDL_MouseY = y;

 		SDL_MoveCursor(SDL_MouseX, SDL_MouseY);

 	}

 	/* Post the event, if desired */

 	posted = 0;

 	if ( SDL_ProcessEvents[event.type] == SDL_ENABLE ) {

 		event.button.state = state;

 		event.button.button = button;

 		event.button.x = x;

 		event.button.y = y;

 		if ( (SDL_EventOK == NULL) || (*SDL_EventOK)(&event) ) {

 			posted = 1;

 			SDL_PushEvent(&event);

 		}

 	}

 	return(posted);

 }