/*

    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"

/* Handle the event stream, converting X11 events into SDL events */

#include <setjmp.h>

#include <X11/Xlib.h>

#include <X11/Xutil.h>

#include <X11/keysym.h>

#ifdef __SVR4

#include <X11/Sunkeysym.h>

#endif

#include <sys/types.h>

#include <sys/time.h>

#include <unistd.h>

#include "SDL_timer.h"

#include "SDL_syswm.h"

#include "../SDL_sysvideo.h"

#include "../../events/SDL_sysevents.h"

#include "../../events/SDL_events_c.h"

#include "SDL_x11video.h"

#include "SDL_x11dga_c.h"

#include "SDL_x11modes_c.h"

#include "SDL_x11image_c.h"

#include "SDL_x11gamma_c.h"

#include "SDL_x11wm_c.h"

#include "SDL_x11mouse_c.h"

#include "SDL_x11events_c.h"

/* Define this if you want to debug X11 events */

/*#define DEBUG_XEVENTS*/

/* The translation tables from an X11 keysym to a SDL keysym */

static SDLKey ODD_keymap[256];

static SDLKey MISC_keymap[256];

SDLKey X11_TranslateKeycode(Display *display, KeyCode kc);

#ifdef X_HAVE_UTF8_STRING

Uint32 Utf8ToUcs4(const Uint8 *utf8)

{

	Uint32 c;

	int i = 1;

	int noOctets = 0;

	int firstOctetMask = 0;

	unsigned char firstOctet = utf8[0];

	if (firstOctet < 0x80) {

		/*

		  Characters in the range:

		    00000000 to 01111111 (ASCII Range)

		  are stored in one octet:

		    0xxxxxxx (The same as its ASCII representation)

		  The least 6 significant bits of the first octet is the most 6 significant nonzero bits

		  of the UCS4 representation.

		*/

		noOctets = 1;

		firstOctetMask = 0x7F;  /* 0(1111111) - The most significant bit is ignored */

	} else if ((firstOctet & 0xE0) /* get the most 3 significant bits by AND'ing with 11100000 */

	              == 0xC0 ) {  /* see if those 3 bits are 110. If so, the char is in this range */

		/*

		  Characters in the range:

		    00000000 10000000 to 00000111 11111111

		  are stored in two octets:

		    110xxxxx 10xxxxxx

		  The least 5 significant bits of the first octet is the most 5 significant nonzero bits

		  of the UCS4 representation.

		*/

		noOctets = 2;

		firstOctetMask = 0x1F;  /* 000(11111) - The most 3 significant bits are ignored */

	} else if ((firstOctet & 0xF0) /* get the most 4 significant bits by AND'ing with 11110000 */

	              == 0xE0) {  /* see if those 4 bits are 1110. If so, the char is in this range */

		/*

		  Characters in the range:

		    00001000 00000000 to 11111111 11111111

		  are stored in three octets:

		    1110xxxx 10xxxxxx 10xxxxxx

		  The least 4 significant bits of the first octet is the most 4 significant nonzero bits

		  of the UCS4 representation.

		*/

		noOctets = 3;

		firstOctetMask = 0x0F; /* 0000(1111) - The most 4 significant bits are ignored */

	} else if ((firstOctet & 0xF8) /* get the most 5 significant bits by AND'ing with 11111000 */

	              == 0xF0) {  /* see if those 5 bits are 11110. If so, the char is in this range */

		/*

		  Characters in the range:

		    00000001 00000000 00000000 to 00011111 11111111 11111111

		  are stored in four octets:

		    11110xxx 10xxxxxx 10xxxxxx 10xxxxxx

		  The least 3 significant bits of the first octet is the most 3 significant nonzero bits

		  of the UCS4 representation.

		*/

		noOctets = 4;

		firstOctetMask = 0x07; /* 11110(111) - The most 5 significant bits are ignored */

	} else if ((firstOctet & 0xFC) /* get the most 6 significant bits by AND'ing with 11111100 */

	              == 0xF8) { /* see if those 6 bits are 111110. If so, the char is in this range */

		/*

		  Characters in the range:

		    00000000 00100000 00000000 00000000 to

		    00000011 11111111 11111111 11111111

		  are stored in five octets:

		    111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx

		  The least 2 significant bits of the first octet is the most 2 significant nonzero bits

		  of the UCS4 representation.

		*/

		noOctets = 5;

		firstOctetMask = 0x03; /* 111110(11) - The most 6 significant bits are ignored */

	} else if ((firstOctet & 0xFE) /* get the most 7 significant bits by AND'ing with 11111110 */

	              == 0xFC) { /* see if those 7 bits are 1111110. If so, the char is in this range */

		/*

		  Characters in the range:

		    00000100 00000000 00000000 00000000 to

		    01111111 11111111 11111111 11111111

		  are stored in six octets:

		    1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx

		  The least significant bit of the first octet is the most significant nonzero bit

		  of the UCS4 representation.

		*/

		noOctets = 6;

		firstOctetMask = 0x01; /* 1111110(1) - The most 7 significant bits are ignored */

	} else

		return 0;  /* The given chunk is not a valid UTF-8 encoded Unicode character */

	/*

	  The least noOctets significant bits of the first octet is the most 2 significant nonzero bits

	  of the UCS4 representation.

	  The first 6 bits of the UCS4 representation is the least 8-noOctets-1 significant bits of

	  firstOctet if the character is not ASCII. If so, it's the least 7 significant bits of firstOctet.

	  This done by AND'ing firstOctet with its mask to trim the bits used for identifying the

	  number of continuing octets (if any) and leave only the free bits (the x's)

	  Sample:

	  1-octet:    0xxxxxxx  &  01111111 = 0xxxxxxx

	  2-octets:  110xxxxx  &  00011111 = 000xxxxx

	*/

	c = firstOctet & firstOctetMask;

	/* Now, start filling c.ucs4 with the bits from the continuing octets from utf8. */

	for (i = 1; i < noOctets; i++) {

		/* A valid continuing octet is of the form 10xxxxxx */

		if ((utf8[i] & 0xC0) /* get the most 2 significant bits by AND'ing with 11000000 */

		    != 0x80) /* see if those 2 bits are 10. If not, the is a malformed sequence. */

			/*The given chunk is a partial sequence at the end of a string that could

			   begin a valid character */

			return 0;

		/* Make room for the next 6-bits */

		c <<= 6;

		/*

		  Take only the least 6 significance bits of the current octet (utf8[i]) and fill the created room

		  of c.ucs4 with them.

		  This done by AND'ing utf8[i] with 00111111 and the OR'ing the result with c.ucs4.

		*/

		c |= utf8[i] & 0x3F;

	}

	return c;

}

/* Given a UTF-8 encoded string pointed to by utf8 of length length in

   bytes, returns the corresponding UTF-16 encoded string in the

   buffer pointed to by utf16.  The maximum number of UTF-16 encoding

   units (i.e., Unit16s) allowed in the buffer is specified in

   utf16_max_length.  The return value is the number of UTF-16

   encoding units placed in the output buffer pointed to by utf16.

   In case of an error, -1 is returned, leaving some unusable partial

   results in the output buffer.

   The caller must estimate the size of utf16 buffer by itself before

   calling this function.  Insufficient output buffer is considered as

   an error, and once an error occured, this function doesn't give any

   clue how large the result will be.

   The error cases include following:

   - Invalid byte sequences were in the input UTF-8 bytes.  The caller

     has no way to know what point in the input buffer was the

     errornous byte.

   - The input contained a character (a valid UTF-8 byte sequence)

     whose scalar value exceeded the range that UTF-16 can represent

     (i.e., characters whose Unicode scalar value above 0x110000).

   - The output buffer has no enough space to hold entire utf16 data.

   Please note:

   - '\0'-termination is not assumed both on the input UTF-8 string

     and on the output UTF-16 string; any legal zero byte in the input

     UTF-8 string will be converted to a 16-bit zero in output.  As a

     side effect, the last UTF-16 encoding unit stored in the output

     buffer will have a non-zero value if the input UTF-8 was not

     '\0'-terminated.

   - UTF-8 aliases are *not* considered as an error.  They are

     converted to UTF-16.  For example, 0xC0 0xA0, 0xE0 0x80 0xA0, 

     and 0xF0 0x80 0x80 0xA0 are all mapped to a single UTF-16

     encoding unit 0x0020.

   - Three byte UTF-8 sequences whose value corresponds to a surrogate

     code or other reserved scalar value are not considered as an

     error either.  They may cause an invalid UTF-16 data (e.g., those

     containing unpaired surrogates).

*/

static int Utf8ToUtf16(const Uint8 *utf8, const int utf8_length, Uint16 *utf16, const int utf16_max_length) {

    /* p moves over the output buffer.  max_ptr points to the next to the last slot of the buffer.  */

    Uint16 *p = utf16;

    Uint16 const *const max_ptr = utf16 + utf16_max_length;

    /* end_of_input points to the last byte of input as opposed to the next to the last byte.  */

    Uint8 const *const end_of_input = utf8 + utf8_length - 1;

    while (utf8 <= end_of_input) {

	Uint8 const c = *utf8;

	if (p >= max_ptr) {

	    /* No more output space.  */

	    return -1;

	}

	if (c < 0x80) {

	    /* One byte ASCII.  */

	    *p++ = c;

	    utf8 += 1;

	} else if (c < 0xC0) {

	    /* Follower byte without preceeding leader bytes.  */

	    return -1;

	} else if (c < 0xE0) {

	    /* Two byte sequence.  We need one follower byte.  */

	    if (end_of_input - utf8 < 1 || (((utf8[1] ^ 0x80)) & 0xC0)) {

		return -1;

	    }

	    *p++ = (Uint16)(0xCF80 + (c << 6) + utf8[1]);

	    utf8 += 2;

	} else if (c < 0xF0) {

	    /* Three byte sequence.  We need two follower byte.  */

	    if (end_of_input - utf8 < 2 || (((utf8[1] ^ 0x80) | (utf8[2] ^ 0x80)) & 0xC0)) {

		return -1;

	    }

	    *p++ = (Uint16)(0xDF80 + (c << 12) + (utf8[1] << 6) + utf8[2]);

	    utf8 += 3;

	} else if (c < 0xF8) {

	    int plane;

	    /* Four byte sequence.  We need three follower bytes.  */

	    if (end_of_input - utf8 < 3 || (((utf8[1] ^ 0x80) | (utf8[2] ^0x80) | (utf8[3] ^ 0x80)) & 0xC0)) {

		return -1;

	    }

	    plane = (-0xC8 + (c << 2) + (utf8[1] >> 4));

	    if (plane == 0) {

		/* This four byte sequence is an alias that

                   corresponds to a Unicode scalar value in BMP.

		   It fits in an UTF-16 encoding unit.  */

		*p++ = (Uint16)(0xDF80 + (utf8[1] << 12) + (utf8[2] << 6) + utf8[3]);

	    } else if (plane <= 16) {

		/* This is a legal four byte sequence that corresponds to a surrogate pair.  */

		if (p + 1 >= max_ptr) {

		    /* No enough space on the output buffer for the pair.  */

		    return -1;

		}

		*p++ = (Uint16)(0xE5B8 + (c << 8) + (utf8[1] << 2) + (utf8[2] >> 4));

		*p++ = (Uint16)(0xDB80 + ((utf8[2] & 0x0F) << 6) + utf8[3]);

	    } else {

		/* This four byte sequence is out of UTF-16 code space.  */

		return -1;

	    }

	    utf8 += 4;

	} else {

	    /* Longer sequence or unused byte.  */

	    return -1;

	}

    }

    return p - utf16;

}

#endif

/* Check to see if this is a repeated key.

   (idea shamelessly lifted from GII -- thanks guys! :)

 */

static int X11_KeyRepeat(Display *display, XEvent *event)

{

	XEvent peekevent;

	int repeated;

	repeated = 0;

	if ( XPending(display) ) {

		XPeekEvent(display, &peekevent);

		if ( (peekevent.type == KeyPress) &&

		     (peekevent.xkey.keycode == event->xkey.keycode) &&

		     ((peekevent.xkey.time-event->xkey.time) < 2) ) {

			repeated = 1;

			XNextEvent(display, &peekevent);

		}

	}

	return(repeated);

}

/* Note:  The X server buffers and accumulates mouse motion events, so

   the motion event generated by the warp may not appear exactly as we

   expect it to.  We work around this (and improve performance) by only

   warping the pointer when it reaches the edge, and then wait for it.

*/

#define MOUSE_FUDGE_FACTOR	8

static __inline__ int X11_WarpedMotion(_THIS, XEvent *xevent)

{

	int w, h, i;

	int deltax, deltay;

	int posted;

	w = SDL_VideoSurface->w;

	h = SDL_VideoSurface->h;

	deltax = xevent->xmotion.x - mouse_last.x;

	deltay = xevent->xmotion.y - mouse_last.y;

#ifdef DEBUG_MOTION

  printf("Warped mouse motion: %d,%d\n", deltax, deltay);

#endif

	mouse_last.x = xevent->xmotion.x;

	mouse_last.y = xevent->xmotion.y;

	posted = SDL_PrivateMouseMotion(0, 1, deltax, deltay);

	if ( (xevent->xmotion.x < MOUSE_FUDGE_FACTOR) ||

	     (xevent->xmotion.x > (w-MOUSE_FUDGE_FACTOR)) ||

	     (xevent->xmotion.y < MOUSE_FUDGE_FACTOR) ||

	     (xevent->xmotion.y > (h-MOUSE_FUDGE_FACTOR)) ) {

		/* Get the events that have accumulated */

		while ( XCheckTypedEvent(SDL_Display, MotionNotify, xevent) ) {

			deltax = xevent->xmotion.x - mouse_last.x;

			deltay = xevent->xmotion.y - mouse_last.y;

#ifdef DEBUG_MOTION

  printf("Extra mouse motion: %d,%d\n", deltax, deltay);

#endif

			mouse_last.x = xevent->xmotion.x;

			mouse_last.y = xevent->xmotion.y;

			posted += SDL_PrivateMouseMotion(0, 1, deltax, deltay);

		}

		mouse_last.x = w/2;

		mouse_last.y = h/2;

		XWarpPointer(SDL_Display, None, SDL_Window, 0, 0, 0, 0,

					mouse_last.x, mouse_last.y);

		for ( i=0; i<10; ++i ) {

        		XMaskEvent(SDL_Display, PointerMotionMask, xevent);

			if ( (xevent->xmotion.x >

			          (mouse_last.x-MOUSE_FUDGE_FACTOR)) &&

			     (xevent->xmotion.x <

			          (mouse_last.x+MOUSE_FUDGE_FACTOR)) &&

			     (xevent->xmotion.y >

			          (mouse_last.y-MOUSE_FUDGE_FACTOR)) &&

			     (xevent->xmotion.y <

			          (mouse_last.y+MOUSE_FUDGE_FACTOR)) ) {

				break;

			}

#ifdef DEBUG_XEVENTS

  printf("Lost mouse motion: %d,%d\n", xevent->xmotion.x, xevent->xmotion.y);

#endif

		}

#ifdef DEBUG_XEVENTS

		if ( i == 10 ) {

			printf("Warning: didn't detect mouse warp motion\n");

		}

#endif

	}

	return(posted);

}

static int X11_DispatchEvent(_THIS)

{

	int posted;

	XEvent xevent;

	SDL_memset(&xevent, '\0', sizeof (XEvent));  /* valgrind fix. --ryan. */

	XNextEvent(SDL_Display, &xevent);

	/* Discard KeyRelease and KeyPress events generated by auto-repeat.

	   We need to do it before passing event to XFilterEvent.  Otherwise,

	   KeyRelease aware IMs are confused...  */

	if ( xevent.type == KeyRelease

	     && X11_KeyRepeat(SDL_Display, &xevent) ) {

		return 0;

	}

#ifdef X_HAVE_UTF8_STRING

	/* If we are translating with IM, we need to pass all events

	   to XFilterEvent, and discard those filtered events immediately.  */

	if ( SDL_TranslateUNICODE

	     && SDL_IM != NULL

	     && XFilterEvent(&xevent, None) ) {

		return 0;

	}

#endif

	posted = 0;

	switch (xevent.type) {

	    /* Gaining mouse coverage? */

	    case EnterNotify: {

#ifdef DEBUG_XEVENTS

printf("EnterNotify! (%d,%d)\n", xevent.xcrossing.x, xevent.xcrossing.y);

if ( xevent.xcrossing.mode == NotifyGrab )

printf("Mode: NotifyGrab\n");

if ( xevent.xcrossing.mode == NotifyUngrab )

printf("Mode: NotifyUngrab\n");

#endif

		if ( (xevent.xcrossing.mode != NotifyGrab) &&

		     (xevent.xcrossing.mode != NotifyUngrab) ) {

			if ( this->input_grab == SDL_GRAB_OFF ) {

				posted = SDL_PrivateAppActive(1, SDL_APPMOUSEFOCUS);

			}

			posted = SDL_PrivateMouseMotion(0, 0,

					xevent.xcrossing.x,

					xevent.xcrossing.y);

		}

	    }

	    break;

	    /* Losing mouse coverage? */

	    case LeaveNotify: {

#ifdef DEBUG_XEVENTS

printf("LeaveNotify! (%d,%d)\n", xevent.xcrossing.x, xevent.xcrossing.y);

if ( xevent.xcrossing.mode == NotifyGrab )

printf("Mode: NotifyGrab\n");

if ( xevent.xcrossing.mode == NotifyUngrab )

printf("Mode: NotifyUngrab\n");

#endif

		if ( (xevent.xcrossing.mode != NotifyGrab) &&

		     (xevent.xcrossing.mode != NotifyUngrab) &&

		     (xevent.xcrossing.detail != NotifyInferior) ) {

			if ( this->input_grab == SDL_GRAB_OFF ) {

				posted = SDL_PrivateAppActive(0, SDL_APPMOUSEFOCUS);

			} else {

				posted = SDL_PrivateMouseMotion(0, 0,

						xevent.xcrossing.x,

						xevent.xcrossing.y);

			}

		}

	    }

	    break;

	    /* Gaining input focus? */

	    case FocusIn: {

#ifdef DEBUG_XEVENTS

printf("FocusIn!\n");

#endif

		posted = SDL_PrivateAppActive(1, SDL_APPINPUTFOCUS);

#ifdef X_HAVE_UTF8_STRING

		if ( SDL_IC != NULL ) {

			XSetICFocus(SDL_IC);

		}

#endif

		/* Queue entry into fullscreen mode */

		switch_waiting = 0x01 | SDL_FULLSCREEN;

		switch_time = SDL_GetTicks() + 1500;

	    }

	    break;

	    /* Losing input focus? */

	    case FocusOut: {

#ifdef DEBUG_XEVENTS

printf("FocusOut!\n");

#endif

		posted = SDL_PrivateAppActive(0, SDL_APPINPUTFOCUS);

#ifdef X_HAVE_UTF8_STRING

		if ( SDL_IC != NULL ) {

			XUnsetICFocus(SDL_IC);

		}

#endif

		/* Queue leaving fullscreen mode */

		switch_waiting = 0x01;

		switch_time = SDL_GetTicks() + 200;

	    }

	    break;

#ifdef X_HAVE_UTF8_STRING

	    /* Some IM requires MappingNotify to be passed to

	       XRefreshKeyboardMapping by the app.  */

	    case MappingNotify: {

		XRefreshKeyboardMapping(&xevent.xmapping);

	    }

	    break;

#endif /* X_HAVE_UTF8_STRING */

	    /* Generated upon EnterWindow and FocusIn */

	    case KeymapNotify: {

#ifdef DEBUG_XEVENTS

printf("KeymapNotify!\n");

#endif

		X11_SetKeyboardState(SDL_Display,  xevent.xkeymap.key_vector);

	    }

	    break;

	    /* Mouse motion? */

	    case MotionNotify: {

		if ( SDL_VideoSurface ) {

			if ( mouse_relative ) {

				if ( using_dga & DGA_MOUSE ) {

#ifdef DEBUG_MOTION

  printf("DGA motion: %d,%d\n", xevent.xmotion.x_root, xevent.xmotion.y_root);

#endif

					posted = SDL_PrivateMouseMotion(0, 1,

							xevent.xmotion.x_root,

							xevent.xmotion.y_root);

				} else {

					posted = X11_WarpedMotion(this,&xevent);

				}