/*
   rdesktop: A Remote Desktop Protocol client.
   User interface services - X keyboard mapping
   Copyright (C) Matthew Chapman 1999-2001
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program 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 General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <X11/Xlib.h>
#define XK_MISCELLANY
#include <X11/keysymdef.h>
#include <ctype.h>
#include <limits.h>
#include <time.h>
#include "rdesktop.h"
#include "scancodes.h"

#define KEYMAP_SIZE 4096
#define KEYMAP_MASK (KEYMAP_SIZE - 1)
#define KEYMAP_MAX_LINE_LENGTH 80

extern Display *display;
extern char keymapname[16];
extern int keylayout;
extern BOOL enable_compose;

static key_translation keymap[KEYMAP_SIZE];
static int min_keycode;
static uint16 remote_modifier_state = 0;

static void update_modifier_state(uint8 scancode, BOOL pressed);

static void
add_to_keymap(char *keyname, uint8 scancode, uint16 modifiers, char *mapname)
{
	KeySym keysym;

	keysym = XStringToKeysym(keyname);
	if (keysym == NoSymbol)
	{
		error("Bad keysym %s in keymap %s\n", keyname, mapname);
		return;
	}

	DEBUG_KBD(("Adding translation, keysym=0x%x, scancode=0x%x, "
		   "modifiers=0x%x\n", (unsigned int) keysym, scancode, modifiers));

	keymap[keysym & KEYMAP_MASK].scancode = scancode;
	keymap[keysym & KEYMAP_MASK].modifiers = modifiers;

	return;
}


static BOOL
xkeymap_read(char *mapname)
{
	FILE *fp;
	char line[KEYMAP_MAX_LINE_LENGTH], path[PATH_MAX];
	unsigned int line_num = 0;
	unsigned int line_length = 0;
	char *keyname, *p;
	char *line_rest;
	uint8 scancode;
	uint16 modifiers;


	strcpy(path, KEYMAP_PATH);
	strncat(path, mapname, sizeof(path) - sizeof(KEYMAP_PATH));

	fp = fopen(path, "r");
	if (fp == NULL)
	{
		error("Failed to open keymap %s\n", path);
		return False;
	}

	/* FIXME: More tolerant on white space */
	while (fgets(line, sizeof(line), fp) != NULL)
	{
		line_num++;

		/* Replace the \n with \0 */
		p = strchr(line, '\n');
		if (p != NULL)
			*p = 0;

		line_length = strlen(line);

		/* Completely empty line */
		if (strspn(line, " \t\n\r\f\v") == line_length)
		{
			continue;
		}

		/* Include */
		if (strncmp(line, "include ", 8) == 0)
		{
			if (!xkeymap_read(line + 8))
				return False;
			continue;
		}

		/* map */
		if (strncmp(line, "map ", 4) == 0)
		{
			keylayout = strtol(line + 4, NULL, 16);
			DEBUG_KBD(("Keylayout 0x%x\n", keylayout));
			continue;
		}

		/* compose */
		if (strncmp(line, "enable_compose", 15) == 0)
		{
			DEBUG_KBD(("Enabling compose handling\n"));
			enable_compose = True;
			continue;
		}

		/* Comment */
		if (line[0] == '#')
		{
			continue;
		}

		/* Normal line */
		keyname = line;
		p = strchr(line, ' ');
		if (p == NULL)
		{
			error("Bad line %d in keymap %s\n", line_num, mapname);
			continue;
		}
		else
		{
			*p = 0;
		}

		/* scancode */
		p++;
		scancode = strtol(p, &line_rest, 16);

		/* flags */
		/* FIXME: Should allow case-insensitive flag names. 
		   Fix by using lex+yacc... */
		modifiers = 0;
		if (strstr(line_rest, "altgr"))
		{
			MASK_ADD_BITS(modifiers, MapAltGrMask);
		}

		if (strstr(line_rest, "shift"))
		{
			MASK_ADD_BITS(modifiers, MapLeftShiftMask);
		}

		if (strstr(line_rest, "numlock"))
		{
			MASK_ADD_BITS(modifiers, MapNumLockMask);
		}

		if (strstr(line_rest, "localstate"))
		{
			MASK_ADD_BITS(modifiers, MapLocalStateMask);
		}

		if (strstr(line_rest, "inhibit"))
		{
			MASK_ADD_BITS(modifiers, MapInhibitMask);
		}

		add_to_keymap(keyname, scancode, modifiers, mapname);

		if (strstr(line_rest, "addupper"))
		{
			/* Automatically add uppercase key, with same modifiers 
			   plus shift */
			for (p = keyname; *p; p++)
				*p = toupper(*p);
			MASK_ADD_BITS(modifiers, MapLeftShiftMask);
			add_to_keymap(keyname, scancode, modifiers, mapname);
		}
	}

	fclose(fp);
	return True;
}


/* Before connecting and creating UI */
void
xkeymap_init(void)
{
	unsigned int max_keycode;

	if (strcmp(keymapname, "none"))
		xkeymap_read(keymapname);

	XDisplayKeycodes(display, &min_keycode, (int *) &max_keycode);
}

/* Handles, for example, multi-scancode keypresses (which is not
   possible via keymap-files) */
BOOL
handle_special_keys(uint32 keysym, unsigned int state, uint32 ev_time, BOOL pressed)
{
	switch (keysym)
	{
		case XK_Break:
			if (get_key_state(state, XK_Alt_L) || get_key_state(state, XK_Alt_R))
			{
				/* toggle full screen */
				if (pressed)
					xwin_toggle_fullscreen();

			}
			else
			{
				/* Send Break sequence E0 46 E0 C6 */
				if (pressed)
				{
					rdp_send_scancode(ev_time, RDP_KEYPRESS,
							  (SCANCODE_EXTENDED | 0x46));
					rdp_send_scancode(ev_time, RDP_KEYPRESS,
							  (SCANCODE_EXTENDED | 0xc6));
				}
				/* No break sequence */
			}

			return True;
			break;

		case XK_Pause:
			/* According to MS Keyboard Scan Code
			   Specification, pressing Pause should result
			   in E1 1D 45 E1 9D C5. I'm not exactly sure
			   of how this is supposed to be sent via
			   RDP. The code below seems to work, but with
			   the side effect that Left Ctrl stays
			   down. Therefore, we release it when Pause
			   is released. */
			if (pressed)
			{
				rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0xe1, 0);
				rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0x1d, 0);
				rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0x45, 0);
				rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0xe1, 0);
				rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0x9d, 0);
				rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYPRESS, 0xc5, 0);
			}
			else
			{
				// Release Left Ctrl
				rdp_send_input(ev_time, RDP_INPUT_SCANCODE, RDP_KEYRELEASE, 0x1d,
					       0);
			}

			return True;
			break;

		case XK_Meta_L:	/* Windows keys */
		case XK_Super_L:
		case XK_Hyper_L:
		case XK_Meta_R:
		case XK_Super_R:
		case XK_Hyper_R:
			if (pressed)
			{
				rdp_send_scancode(ev_time, RDP_KEYPRESS, SCANCODE_CHAR_LCTRL);
				rdp_send_scancode(ev_time, RDP_KEYPRESS, SCANCODE_CHAR_ESC);
			}
			else
			{
				rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_ESC);
				rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_LCTRL);
			}
			return True;
			break;
	}
	return False;
}


key_translation
xkeymap_translate_key(uint32 keysym, unsigned int keycode, unsigned int state)
{
	key_translation tr = { 0, 0 };

	tr = keymap[keysym & KEYMAP_MASK];

	if (tr.modifiers & MapInhibitMask)
	{
		DEBUG_KBD(("Inhibiting key\n"));
		tr.scancode = 0;
		return tr;
	}

	if (tr.modifiers & MapLocalStateMask)
	{
		/* The modifiers to send for this key should be obtained
		   from the local state. Currently, only shift is implemented. */
		if (state & ShiftMask)
		{
			tr.modifiers = MapLeftShiftMask;
		}
	}

	if (tr.scancode != 0)
	{
		DEBUG_KBD(("Found key translation, scancode=0x%x, modifiers=0x%x\n",
			   tr.scancode, tr.modifiers));
		return tr;
	}

	DEBUG_KBD(("No translation for (keysym 0x%lx, %s)\n", keysym, get_ksname(keysym)));

	/* not in keymap, try to interpret the raw scancode */
	if ((keycode >= min_keycode) && (keycode <= 0x60))
	{
		tr.scancode = keycode - min_keycode;

		/* The modifiers to send for this key should be
		   obtained from the local state. Currently, only
		   shift is implemented. */
		if (state & ShiftMask)
		{
			tr.modifiers = MapLeftShiftMask;
		}

		DEBUG_KBD(("Sending guessed scancode 0x%x\n", tr.scancode));
	}
	else
	{
		DEBUG_KBD(("No good guess for keycode 0x%x found\n", keycode));
	}

	return tr;
}

uint16
xkeymap_translate_button(unsigned int button)
{
	switch (button)
	{
		case Button1:	/* left */
			return MOUSE_FLAG_BUTTON1;
		case Button2:	/* middle */
			return MOUSE_FLAG_BUTTON3;
		case Button3:	/* right */
			return MOUSE_FLAG_BUTTON2;
		case Button4:	/* wheel up */
			return MOUSE_FLAG_BUTTON4;
		case Button5:	/* wheel down */
			return MOUSE_FLAG_BUTTON5;
	}

	return 0;
}

char *
get_ksname(uint32 keysym)
{
	char *ksname = NULL;

	if (keysym == NoSymbol)
		ksname = "NoSymbol";
	else if (!(ksname = XKeysymToString(keysym)))
		ksname = "(no name)";

	return ksname;
}


void
ensure_remote_modifiers(uint32 ev_time, key_translation tr)
{
	/* If this key is a modifier, do nothing */
	switch (tr.scancode)
	{
		case SCANCODE_CHAR_LSHIFT:
		case SCANCODE_CHAR_RSHIFT:
		case SCANCODE_CHAR_LCTRL:
		case SCANCODE_CHAR_RCTRL:
		case SCANCODE_CHAR_LALT:
		case SCANCODE_CHAR_RALT:
		case SCANCODE_CHAR_LWIN:
		case SCANCODE_CHAR_RWIN:
		case SCANCODE_CHAR_NUMLOCK:
			return;
		default:
			break;
	}

	/* Shift. Left shift and right shift are treated as equal; either is fine. */
	if (MASK_HAS_BITS(tr.modifiers, MapShiftMask)
	    != MASK_HAS_BITS(remote_modifier_state, MapShiftMask))
	{
		/* The remote modifier state is not correct */
		if (MASK_HAS_BITS(tr.modifiers, MapLeftShiftMask))
		{
			/* Needs left shift. Send down. */
			rdp_send_scancode(ev_time, RDP_KEYPRESS, SCANCODE_CHAR_LSHIFT);
		}
		else if (MASK_HAS_BITS(tr.modifiers, MapRightShiftMask))
		{
			/* Needs right shift. Send down. */
			rdp_send_scancode(ev_time, RDP_KEYPRESS, SCANCODE_CHAR_RSHIFT);
		}
		else
		{
			/* Should not use this modifier. Send up for shift currently pressed. */
			if (MASK_HAS_BITS(remote_modifier_state, MapLeftShiftMask))
				/* Left shift is down */
				rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_LSHIFT);
			else
				/* Right shift is down */
				rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_RSHIFT);
		}
	}

	/* AltGr */
	if (MASK_HAS_BITS(tr.modifiers, MapAltGrMask)
	    != MASK_HAS_BITS(remote_modifier_state, MapAltGrMask))
	{
		/* The remote modifier state is not correct */
		if (MASK_HAS_BITS(tr.modifiers, MapAltGrMask))
		{
			/* Needs this modifier. Send down. */
			rdp_send_scancode(ev_time, RDP_KEYPRESS, SCANCODE_CHAR_RALT);
		}
		else
		{
			/* Should not use this modifier. Send up. */
			rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_RALT);
		}
	}

	/* NumLock */
	if (MASK_HAS_BITS(tr.modifiers, MapNumLockMask)
	    != MASK_HAS_BITS(remote_modifier_state, MapNumLockMask))
	{
		/* The remote modifier state is not correct */
		uint16 new_remote_state = 0;

		if (MASK_HAS_BITS(tr.modifiers, MapNumLockMask))
		{
			DEBUG_KBD(("Remote NumLock state is incorrect, activating NumLock.\n"));
			new_remote_state |= KBD_FLAG_NUMLOCK;
		}
		else
		{
			DEBUG_KBD(("Remote NumLock state is incorrect, deactivating NumLock.\n"));
		}

		rdp_send_input(0, RDP_INPUT_SYNCHRONIZE, 0, new_remote_state, 0);
		update_modifier_state(SCANCODE_CHAR_NUMLOCK, True);
	}
}


void
reset_modifier_keys(unsigned int state)
{
	/* reset keys */
	uint32 ev_time;
	ev_time = time(NULL);

	if (MASK_HAS_BITS(remote_modifier_state, MapLeftShiftMask) && !get_key_state(state, XK_Shift_L))
		rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_LSHIFT);

	if (MASK_HAS_BITS(remote_modifier_state, MapRightShiftMask) && !get_key_state(state, XK_Shift_R))
		rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_RSHIFT);

	if (MASK_HAS_BITS(remote_modifier_state, MapLeftCtrlMask) && !get_key_state(state, XK_Control_L))
		rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_LCTRL);

	if (MASK_HAS_BITS(remote_modifier_state, MapRightCtrlMask) && !get_key_state(state, XK_Control_R))
		rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_RCTRL);

	if (MASK_HAS_BITS(remote_modifier_state, MapLeftAltMask) && !get_key_state(state, XK_Alt_L))
		rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_LALT);

	if (MASK_HAS_BITS(remote_modifier_state, MapRightAltMask) &&
	    !get_key_state(state, XK_Alt_R) && !get_key_state(state, XK_Mode_switch))
		rdp_send_scancode(ev_time, RDP_KEYRELEASE, SCANCODE_CHAR_RALT);
}


static void
update_modifier_state(uint8 scancode, BOOL pressed)
{
#ifdef WITH_DEBUG_KBD
	uint16 old_modifier_state;

	old_modifier_state = remote_modifier_state;
#endif

	switch (scancode)
	{
		case SCANCODE_CHAR_LSHIFT:
			MASK_CHANGE_BIT(remote_modifier_state, MapLeftShiftMask, pressed);
			break;
		case SCANCODE_CHAR_RSHIFT:
			MASK_CHANGE_BIT(remote_modifier_state, MapRightShiftMask, pressed);
			break;
		case SCANCODE_CHAR_LCTRL:
			MASK_CHANGE_BIT(remote_modifier_state, MapLeftCtrlMask, pressed);
			break;
		case SCANCODE_CHAR_RCTRL:
			MASK_CHANGE_BIT(remote_modifier_state, MapRightCtrlMask, pressed);
			break;
		case SCANCODE_CHAR_LALT:
			MASK_CHANGE_BIT(remote_modifier_state, MapLeftAltMask, pressed);
			break;
		case SCANCODE_CHAR_RALT:
			MASK_CHANGE_BIT(remote_modifier_state, MapRightAltMask, pressed);
			break;
		case SCANCODE_CHAR_LWIN:
			MASK_CHANGE_BIT(remote_modifier_state, MapLeftWinMask, pressed);
			break;
		case SCANCODE_CHAR_RWIN:
			MASK_CHANGE_BIT(remote_modifier_state, MapRightWinMask, pressed);
			break;
		case SCANCODE_CHAR_NUMLOCK:
			/* KeyReleases for NumLocks are sent immediately. Toggle the
			   modifier state only on Keypress */
			if (pressed)
			{
				BOOL newNumLockState;
				newNumLockState =
					(MASK_HAS_BITS
					 (remote_modifier_state, MapNumLockMask) == False);
				MASK_CHANGE_BIT(remote_modifier_state,
						MapNumLockMask, newNumLockState);
			}
			break;
	}

#ifdef WITH_DEBUG_KBD
	if (old_modifier_state != remote_modifier_state)
	{
		DEBUG_KBD(("Before updating modifier_state:0x%x, pressed=0x%x\n",
			   old_modifier_state, pressed));
		DEBUG_KBD(("After updating modifier_state:0x%x\n", remote_modifier_state));
	}
#endif

}

/* Send keyboard input */
void
rdp_send_scancode(uint32 time, uint16 flags, uint8 scancode)
{
	update_modifier_state(scancode, !(flags & RDP_KEYRELEASE));

	if (scancode & SCANCODE_EXTENDED)
	{
		DEBUG_KBD(("Sending extended scancode=0x%x, flags=0x%x\n",
			   scancode & ~SCANCODE_EXTENDED, flags));
		rdp_send_input(time, RDP_INPUT_SCANCODE, flags | KBD_FLAG_EXT,
			       scancode & ~SCANCODE_EXTENDED, 0);
	}
	else
	{
		DEBUG_KBD(("Sending scancode=0x%x, flags=0x%x\n", scancode, flags));
		rdp_send_input(time, RDP_INPUT_SCANCODE, flags, scancode, 0);
	}
}