/*

    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);

}