/*
 * (C) Copyright 1992, ..., 2014 the "DOSEMU-Development-Team".
 *
 * for details see file COPYING in the DOSEMU distribution
 */

#include <string.h>
#include <limits.h>
#include <X11/X.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/keysym.h>
#include "x_config.hh"
#include "keyboard/keyboard.h"
#include "keyboard/keyb_clients.h"
#include "emu.h"
#include "utilities.h"
#include "keyb_X.h"
#include "keyboard/keynum.h"
#include "translate/translate.h"
#include "X.h"
#ifdef HAVE_XKB
#include <X11/XKBlib.h>
#include <X11/extensions/XKBgeom.h>
#endif

static XIM im;
static XIC ic;

struct X_keyb_config {
	char *X_keysym;
	char *Dosemu_keysym;
	char *next;
};
struct X_keyb_config *keyb_config = NULL;

#define MAX_X_KEYCODES 256
static int keycode_to_keynum[MAX_X_KEYCODES];
#define KEYCODE_TO_KEYNUM(i) k2kn(i)

#if 0
const char *XStatusString(Status status)
{
	static const char *status_names[] =
	{
		"Success",
		"BadRequest",
		"BadValue",
		"BadWindow",
		"BadPixmap",
		"BadAtom",
		"BadCursor",
		"BadFont",
		"BadMatch",
		"BadDrawable",
		"BadAccess",
		"BadAlloc",
		"BadColor",
		"BadGC",
		"BadIDChoice",
		"BadName",
		"BadLength",
		"BadImplementation",
	};
	const char *result = "Unknown Status code";
	if (status <= sizeof(status_names)/sizeof(status_names[0])) {
		result = status_names[status];
	}
	return result;
};

static void X_print_atom(Display *display, Atom atom)
{
	char *str;
	if (atom != None) {
		str = XGetAtomName(display, atom);
		X_printf("%s", str);
		XFree(str);
	} else {
		X_printf("None");
	}
}
#define X_atom(atom) X_print_atom(display, atom)

static void display_x_components(Display *display)
{
#ifdef HAVE_XKB
	XkbComponentNamesRec names = {
		"*","*", "*", "*", "*", "*"
	};
	XkbComponentListPtr list;
	int max_inout;
	int i;

	max_inout = 1024;
	list = XkbListComponents(display, XkbUseCoreKbd, &names, &max_inout);
	X_printf("X: Components(%d)\n", max_inout);
	X_printf("X:  keymaps(%d)\n", list->num_keymaps);
	for(i = 0; i < list->num_keymaps; i++) {
		X_printf("X:   flag: %d name %s\n",
			list->keymaps[i].flags,
			list->keymaps[i].name);
	}
	X_printf("X:  keycodes(%d)\n", list->num_keycodes);
	for(i = 0; i < list->num_keycodes; i++) {
		X_printf("X:   flag: %d name %s\n",
			list->keycodes[i].flags,
			list->keycodes[i].name);
	}
	X_printf("X:  types(%d)\n", list->num_types);
	for(i = 0; i < list->num_types; i++) {
		X_printf("X:   flag: %d name %s\n",
			list->types[i].flags,
			list->types[i].name);
	}
	X_printf("X:  compat(%d)\n", list->num_compat);
	for(i = 0; i < list->num_compat; i++) {
		X_printf("X:   flag: %d name %s\n",
			list->compat[i].flags,
			list->compat[i].name);
	}
	X_printf("X:  symbols(%d)\n", list->num_symbols);
	for(i = 0; i < list->num_symbols; i++) {
		X_printf("X:   flag: %d name %s\n",
			list->symbols[i].flags,
			list->symbols[i].name);
	}
	X_printf("X:  geometry(%d)\n", list->num_geometry);
	for(i = 0; i < list->num_geometry; i++) {
		X_printf("X:   flag: %d name %s\n",
			list->geometry[i].flags,
			list->geometry[i].name);
	}

	XkbFreeComponentList(list);
#endif /* HAVE_XKB */
}
static void display_x_keyboard(Display *display)
{
#ifdef HAVE_XKB
	int i;
	XkbDescPtr desc;
	XkbNamesPtr names;
	XkbGeometryPtr geom;
	Status status;
	if (!USING_XKB) {
		X_printf("X: Not using Xkb extension\n");
		return;
	}
#if 0
	desc = XkbAllocKeyboard();
#else
	desc = XkbGetKeyboard(display, XkbAllComponentsMask, XkbUseCoreKbd);
#endif
	if (!desc) {
		X_printf("X: No keyboard description!\n");
		return;
	}
	X_printf("X: keycodes min:%d max:%d\n",
		desc->min_key_code, desc->max_key_code);

#if 0
	status = XkbGetNames(display, XkbAllNamesMask, desc);
	if (status != Success) {
		X_printf("XkbGetNames failed: %d %s\n",
			status,
			XStatusString(status)
			);
	}
#endif


	names = desc->names;
	if (!names) {
		X_printf("X: No keyboard names!\n");
	} else {
		X_printf("X: Names\n");
		/* Print Keyboard Names */
		X_printf("X: keycodes: "); X_atom(names->keycodes); X_printf("\n");
		X_printf("X: geometry: "); X_atom(names->geometry); X_printf("\n");
		X_printf("X: symbols: ");  X_atom(names->symbols);  X_printf("\n");
		X_printf("X: types: ");    X_atom(names->types);    X_printf("\n");
		X_printf("X: compat: ");   X_atom(names->compat);   X_printf("\n");
		for(i = 0; i < XkbNumVirtualMods; i++) {
			X_printf("X: vmod(%i): ", i);
			X_atom(names->vmods[i]);
			X_printf("\n");
		}
		for(i = 0; i < XkbNumIndicators; i++) {
			X_printf("X: indicator(%i): ", i);
			X_atom(names->indicators[i]);
			X_printf("\n");
		}
		for(i = 0; i < XkbNumKbdGroups; i++) {
			X_printf("X: group(%i): ", i);
			X_atom(names->groups[i]);
			X_printf("\n");
		}
		X_printf("X: key_names (%d)\n", names->num_keys);
		for(i = desc->min_key_code; i <= desc->max_key_code; i++) {
			int j;
			X_printf("X: %d->%.*s\n",
				i, sizeof(names->keys[i].name), names->keys[i].name);
		}
		X_printf("X: key_aliases (%d)\n", names->num_key_aliases);
		for(i = 0; i < names->num_key_aliases; i++) {
			X_printf("%s->%s\n",
				names->key_aliases[i].alias,
				names->key_aliases[i].real);
		}
		X_printf("X: radio_groups (%d)\n", names->num_rg);
		for(i = 0; i < names->num_rg; i++) {
			X_printf("X: %i->", i);
			X_atom(names->radio_groups[i]);
			X_printf("\n");
		}
		X_printf("X: phys_symbols: "); X_atom(names->phys_symbols); X_printf("\n");
	}


	/* Geometry */
	geom = desc->geom;
	if (!geom) {
		X_printf("X: No keyboard geometry!\n");
	} else {
		/* Print Keyboard Geometry */
		X_printf("X: Geometry "); X_atom(geom->name); X_printf("\n");

		X_printf("X: key_aliases(%d)\n", geom->sz_key_aliases);
		for(i = 0; i < geom->sz_key_aliases; i++) {
			X_printf("%s->%s\n",
				geom->key_aliases[i].alias,
				geom->key_aliases[i].real);
		}
		X_printf("X: sections(%d)\n", geom->sz_sections);
		for(i = 0; i < geom->sz_sections; i++) {
			int j;
			XkbSectionPtr section;
			section = geom->sections +i;
			X_printf("X: section "); X_atom(section->name); X_printf("\n");
			for(j = 0; j < section->num_rows; j++) {
				int k;
				XkbRowPtr row;
				row = section->rows +j;
				X_printf("X:  row(%d)\n", row->num_keys);
				for(k = 0; k < row->num_keys; k++) {
					XkbKeyPtr key;
					key = row->keys + k;
					X_printf("X:   key(%d): %.*s\n",
						k, sizeof(key->name.name), key->name.name);

				}
			}
		}
	}

	XkbFreeKeyboard(desc, XkbAllNamesMask, TRUE);
#endif /* HAVE_XKB */
}

#endif

#ifdef HAVE_XKB
static int XkbFindKeycodeByName(XkbDescPtr xkb, const char *name,Bool use_aliases)
{
	register int	i;

	if ((!xkb)||(!xkb->names)||(!xkb->names->keys))
		return 0;
	for (i=xkb->min_key_code;i<=xkb->max_key_code;i++) {
		if (strncmp(xkb->names->keys[i].name,name,XkbKeyNameLength)==0)
			return i;
	}
	if (!use_aliases)
		return 0;
	if (xkb->geom && xkb->geom->key_aliases) {
		XkbKeyAliasPtr	a;
		a= xkb->geom->key_aliases;
		for (i=0;i<xkb->geom->num_key_aliases;i++,a++) {
			if (strncmp(name,a->alias,XkbKeyNameLength)==0)
				return XkbFindKeycodeByName(xkb,a->real,False);
		}
	}
	if (xkb->names && xkb->names->key_aliases) {
		XkbKeyAliasPtr	a;
		a= xkb->names->key_aliases;
		for (i=0;i<xkb->names->num_key_aliases;i++,a++) {
			if (strncmp(name,a->alias,XkbKeyNameLength)==0)
				return XkbFindKeycodeByName(xkb,a->real,False);
		}
	}
	return 0;
}
#endif


/* List the X keycode to dosemu keynum mapping by X keycode name.
 * This list is all we need to handle general pc style keyboards,
 * and to work reasonably well on most others.
 *
 * This list doesn't handle all keycodes.  If this causes
 * a problem feel free to extend it.  The only rule is that items
 * earlier in the list (if found) will have precedence over items
 * later in the list.
 */
static const struct {
	t_keynum keynum;
	const char *keycode_name;
} keynum_from_keycode[] =
{
	/* shift keys */
	{ NUM_L_ALT	, "LALT"},
	{ NUM_R_ALT	, "RALT"},
	{ NUM_L_CTRL	, "LCTL"},
	{ NUM_R_CTRL	, "RCTL"},
	{ NUM_L_SHIFT	, "LFSH"},
	{ NUM_R_SHIFT	, "RTSH"},
	{ NUM_NUM	, "NMLK"},
	{ NUM_SCROLL	, "SCLK"},
	{ NUM_CAPS	, "CAPS"},

/* main block */

	{ NUM_SPACE      , "SPCE" },
	{ NUM_BKSP	 , "BKSP" },
	{ NUM_RETURN	 , "RTRN" },
	{ NUM_TAB	 , "TAB" },
	{ NUM_A		 , "AC01" },
	{ NUM_B		 , "AB05" },
	{ NUM_C		 , "AB03" },
	{ NUM_D		 , "AC03" },
	{ NUM_E		 , "AD03" },
	{ NUM_F		 , "AC04" },
	{ NUM_G		 , "AC05" },
	{ NUM_H		 , "AC06" },
	{ NUM_I		 , "AD08" },
	{ NUM_J		 , "AC07" },
	{ NUM_K		 , "AC08" },
	{ NUM_L		 , "AC09" },
	{ NUM_M		 , "AB07" },
	{ NUM_N		 , "AB06" },
	{ NUM_O		 , "AD09" },
	{ NUM_P		 , "AD10" },
	{ NUM_Q		 , "AD01" },
	{ NUM_R		 , "AD04" },
	{ NUM_S		 , "AC02" },
	{ NUM_T		 , "AD05" },
	{ NUM_U		 , "AD07" },
	{ NUM_V		 , "AB04" },
	{ NUM_W		 , "AD02" },
	{ NUM_X		 , "AB02" },
	{ NUM_Y		 , "AD06" },
	{ NUM_Z		 , "AB01" },
	{ NUM_1		 , "AE01" },
	{ NUM_2		 , "AE02" },
	{ NUM_3		 , "AE03" },
	{ NUM_4		 , "AE04" },
	{ NUM_5		 , "AE05" },
	{ NUM_6		 , "AE06" },
	{ NUM_7		 , "AE07" },
	{ NUM_8		 , "AE08" },
	{ NUM_9		 , "AE09" },
	{ NUM_0		 , "AE10" },
	{ NUM_DASH	 , "AE11" },
	{ NUM_EQUALS	 , "AE12" },
	{ NUM_LBRACK	 , "AD11" },
	{ NUM_RBRACK	 , "AD12" },
	{ NUM_SEMICOLON	 , "AC10" },
	{ NUM_APOSTROPHE , "AC11" },
	{ NUM_GRAVE	 , "TLDE" },
	{ NUM_BACKSLASH	 , "BKSL" },
	{ NUM_COMMA	 , "AB08" },
	{ NUM_PERIOD	 , "AB09" },
	{ NUM_SLASH	 , "AB10" },
	{ NUM_LESSGREATER, "LSGT" },/* not on US keyboards */

	/* keypad */

	{ NUM_PAD_0	 , "KP0"},
	{ NUM_PAD_1	 , "KP1"},
	{ NUM_PAD_2	 , "KP2"},
	{ NUM_PAD_3	 , "KP3"},
	{ NUM_PAD_4	 , "KP4"},
	{ NUM_PAD_5	 , "KP5"},
	{ NUM_PAD_6	 , "KP6"},
	{ NUM_PAD_7	 , "KP7"},
	{ NUM_PAD_8	 , "KP8"},
	{ NUM_PAD_9	 , "KP9"},
	{ NUM_PAD_DECIMAL, "KPDL"},
	{ NUM_PAD_SLASH	 , "KPDV"},
	{ NUM_PAD_AST	 , "KPMU"},
	{ NUM_PAD_MINUS	 , "KPSU"},
	{ NUM_PAD_PLUS	 , "KPAD"},
	{ NUM_PAD_ENTER	 , "KPEN"},

	/* function keys */

	{ NUM_ESC, "ESC"},
	{ NUM_F1 , "FK01"},
	{ NUM_F2 , "FK02"},
	{ NUM_F3 , "FK03"},
	{ NUM_F4 , "FK04"},
	{ NUM_F5 , "FK05"},
	{ NUM_F6 , "FK06"},
	{ NUM_F7 , "FK07"},
	{ NUM_F8 , "FK08"},
	{ NUM_F9 , "FK09"},
	{ NUM_F10, "FK10"},
	{ NUM_F11, "FK11"},
	{ NUM_F12, "FK12"},

	/* cursor block */

	{ NUM_INS  , "INS"},
	{ NUM_DEL  , "DELE"},
	{ NUM_HOME , "HOME"},
	{ NUM_END  , "END"},
	{ NUM_PGUP , "PGUP"},
	{ NUM_PGDN , "PGDN"},
	{ NUM_UP   , "UP"},
	{ NUM_DOWN , "DOWN"},
	{ NUM_LEFT , "LEFT"},
	{ NUM_RIGHT, "RGHT"},

	/* New keys on a Microsoft Windows keyboard */
	{ NUM_LWIN, "LWIN"},
	{ NUM_RWIN, "RWIN"},
	{ NUM_MENU, "MENU"},

	/* Dual scancode keys */
	{ NUM_PRTSCR_SYSRQ, "PRSC"},
	{ NUM_PAUSE_BREAK,  "PAUS"},

	/* I had to the following to my X keyboard map
	 * to actually get sysrq and break to work...
	 *
	 *  <EXEC> = 92;
	 *  <BRK>  = 114;
	 *  key <EXEC> {
	 *	 type= "PC_SYSRQ",
	 *	 symbols[Group1]= [           Print,         Execute ]
	 *  };
	 *  key <BRK> {
	 *	 type= "PC_BREAK",
	 *	 symbols[Group1]= [           Pause,           Break ]
	 *  };
	 * -- EB 26 March 2000
	 */


	/* Try to catch the other scancode */
	{ NUM_PRTSCR_SYSRQ, "EXEC"},
	{ NUM_PAUSE_BREAK,  "BRK"},
	{ NUM_PAUSE_BREAK,  "BREA"},
};

static t_keynum k2kn(KeyCode xcode)
{
	int idx = keycode_to_keynum[xcode];
	if (idx == -1)
		return NUM_VOID;
	return keynum_from_keycode[idx].keynum;
}

KeyCode keynum_to_keycode(t_keynum keynum)
{
	int i, j;
	for (i = 0; i < ARRAY_SIZE(keynum_from_keycode); i++) {
		if (keynum_from_keycode[i].keynum == keynum)
			break;
	}
	if (i == ARRAY_SIZE(keynum_from_keycode))
		return 0;
	for (j = 0; j < MAX_X_KEYCODES; j++) {
		if (keycode_to_keynum[j] == i)
			break;
	}
	if (j == MAX_X_KEYCODES)
		return 0;
	return j;
}

static Boolean setup_keycode_to_keynum_mapping(Display *display)
{
#ifdef HAVE_XKB
	int i;
	XkbDescPtr desc;
	desc = XkbGetKeyboard(display, XkbAllComponentsMask,
		XkbUseCoreKbd);
	if (!desc) {
		X_printf("X: No keyboard Description!\n");
		return FALSE;
	}
	for(i = 0;
		i < sizeof(keynum_from_keycode)/sizeof(keynum_from_keycode[0]);
		i++) {
		KeyCode xcode;
		xcode = XkbFindKeycodeByName(desc,
			keynum_from_keycode[i].keycode_name, TRUE);
		X_printf("X: looking for %s\n", keynum_from_keycode[i].keycode_name);
		if (xcode && (KEYCODE_TO_KEYNUM(xcode) == NUM_VOID)) {
			keycode_to_keynum[xcode] = i;
			X_printf("X: mapping %s(%02x) -> %02x\n",
				keynum_from_keycode[i].keycode_name,
				xcode,
				keynum_from_keycode[i].keynum);
		}
	}
	XkbFreeKeyboard(desc, XkbAllComponentsMask, TRUE);
	return TRUE;
#else /* !HAVE_XKB */
	return FALSE;
#endif /* HAVE_XKB */
}

static void setup_keycode_to_keynum(void *p, t_unicode dosemu_keysym,
	const unsigned char *str, size_t str_len)
{
	KeySym xkey;
	Display *display = p;
	KeyCode xcode;
	t_keynum keynum;
	t_modifiers modifiers;
	int map;
	xkey = *((const KeySym *)str);
	keynum = keysym_to_keynum(dosemu_keysym, &modifiers);
	xcode = XKeysymToKeycode(display, xkey);
	// Use only plain and shifted keys for layout detection, and
	// match shift state.
	// This prevents things like mapping the key used for "Pilcrow
	// Sign (0xB6)", which is (AltGr)-'r' for a german keyboard to
	// 't', because the pilcrow sign is at position 20 (Ctrl-T) in
	// CP437/CP850.
	switch(modifiers)
	{
		case 0:
			map = 0;
			break;
		case MODIFIER_SHIFT:
			map = 1;
			break;
		default:
			map = -1;
			break;
	}
	if ((map != -1) && (xcode && keynum != NUM_VOID)) {
		int keysyms_per_keycode;
		KeySym *sym = XGetKeyboardMapping (display, xcode, 1,
						   &keysyms_per_keycode);
		if (map < keysyms_per_keycode && sym[map] == xkey) {
			int i;
			for(i = 0; i < sizeof(keynum_from_keycode)/sizeof(keynum_from_keycode[0]);
					i++) {
				if (keynum_from_keycode[i].keynum == keynum) {
					keycode_to_keynum[xcode] = i;
					break;
				}
			}
		}
		XFree(sym);
	}
}

static int X_keycode_initialized = 0;
void X_keycode_initialize(Display *display)
{
	int i;
	Boolean worked;
	if (X_keycode_initialized)
		return;
	X_keycode_initialized = 1;

	for(i = 0; i < MAX_X_KEYCODES; i++) {
		keycode_to_keynum[i] = -1;
	}
#if 0
	display_x_keyboard(display);
	display_x_components(display);
#endif
	worked = FALSE;
	worked = setup_keycode_to_keynum_mapping(display);
	if (!worked) {
		foreach_character_mapping(
			lookup_charset("X_keysym"),
			display, setup_keycode_to_keynum);
	}
#if 1
	for(i = 0; i < MAX_X_KEYCODES; i++) {
		t_keynum keynum = KEYCODE_TO_KEYNUM(i);
		if (keynum != NUM_VOID) {
			k_printf("mapping keycode:%d  -> keynum: 0x%02x\n",
				 i, keynum);
		}
	}
#endif

	im = XOpenIM(display, NULL, NULL, NULL);
	ic = XCreateIC(im, XNInputStyle, XIMPreeditNothing | XIMStatusNothing,
		NULL);
}

static void put_keycode(int make, int keycode, t_keysym sym)
{
	t_keysym keynum;
	keynum = KEYCODE_TO_KEYNUM(keycode);
	if (keynum == NUM_VOID)
		return;
	move_keynum(make, keynum, sym);
}

static void put_keycode_grp(int make, int keycode, int mods)
{
	t_keysym keynum;
	keynum = KEYCODE_TO_KEYNUM(keycode);
	if (keynum == NUM_VOID)
		return;
#ifdef HAVE_XKB
	move_keynum_grp(make, keynum, XkbGroupForCoreState(mods));
#else
	move_keynum(make, keynum, DKY_VOID);
#endif
}

#ifdef HAVE_XKB
static t_unicode Xkb_lookup_key(Display *display, XKeyEvent *e)
{
	t_unicode key = DKY_VOID;
	KeySym xkey = XK_VoidSymbol;
	unsigned int modifiers = 0;
	unsigned int rem_mods;
	char chars[MB_LEN_MAX];
	struct char_set_state cs;
	int rc;
	struct modifier_info X_mi = X_get_modifier_info();

	rc = XkbLookupKeySym(display, e->keycode, e->state, &modifiers, &xkey);
	if (!rc)
		return DKY_VOID;
	rem_mods = e->state & ~modifiers;
	/* XXX alt is not represented in a sym and doesn't return error
	 * from XkbTranslateKeySym(), so disable it by hands. :( */
	if (rem_mods & (X_mi.AltMask | X_mi.AltGrMask))
		return DKY_VOID;
	/* XXX Ctrl-Enter seems to be misconfigured:
	 * https://github.com/stsp/dosemu2/issues/864
	 * Disable it for now. */
	if (xkey == XK_Return && (rem_mods & ControlMask))
		return DKY_VOID;
	rc = Xutf8LookupString(ic, e, chars, MB_LEN_MAX, NULL, NULL);
	if (!rc)
		return DKY_VOID;

	init_charset_state(&cs, lookup_charset("utf8"));
	charset_to_unicode(&cs, &key,
		(const unsigned char *)chars, MB_LEN_MAX);
	cleanup_charset_state(&cs);
	return key;
}
#endif

#if 0
void X_keycode_process_keys(XKeymapEvent *e)
{
	int i;
	char *key_vector;
	int length;
	if (!X_keycode_initialized) {
		X_keycode_initialize(display);
	}
	key_vector = e->key_vector;
	length = sizeof(e->key_vector);
	for(i = 0; i < length; i++) {
		int j;
		int c;
		c = key_vector[i];
		/* for each bit */
		for(j = 0; j < 8; j++) {
			int keycode;
			int pressed;
			keycode = i*8 + j;
			pressed = c & (1 << j);
			put_keycode(pressed, keycode, DKY_VOID);
		}
	}
}
#endif

void X_keycode_process_key(Display *display, XKeyEvent *e)
{
	t_unicode key;
#ifndef HAVE_XKB
	struct mapped_X_event event;
#endif
	Boolean make;

	if (!X_keycode_initialized) {
		X_keycode_initialize(display);
	}
#if 1
	k_printf("KBD:Xev: keycode = %d type = %d\n",
		 e->keycode, e->type);
#endif
	make = e->type == KeyPress;
	X_sync_shiftstate(make, e->keycode, e->state);
	if (!config.layout_auto) {
		/* use classic X_keycode mode from dosemu1.
		 * We don't need xkb here as we are only interested
		 * in a symbol group. */
		put_keycode_grp(make, e->keycode, e->state);
		return;
	}
#ifdef HAVE_XKB
	key = Xkb_lookup_key(display, e);
#else
	map_X_event(display, e, &event);
	key = event.key;
#endif
	if (KEYCODE_TO_KEYNUM(e->keycode) == NUM_L_SHIFT ||
			KEYCODE_TO_KEYNUM(e->keycode) == NUM_R_SHIFT)
		X_force_mouse_cursor(make);
	if (key == DKY_VOID)
		put_keycode_grp(make, e->keycode, e->state);
	else
		put_keycode(make, e->keycode, key);
}