#include <assert.h>
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <xcb-imdkit/encoding.h>
#include <xkbcommon/xkbcommon.h>
#include <xkbcommon/xkbcommon-keysyms.h>

uint32_t keymaplookup(struct xkb_state*, uint8_t, uint16_t);
char *ximcompound(const char*, size_t, size_t*);

enum
{
	ShiftMask = 1<<0,
	LockMask = 1<<1,
	Mod2Mask = 1<<4,
	Mod5Mask = 1<<7,
	Group1 = 1<<13,
};

static struct xkb_state*
keystate(const char *layout)
{
	struct xkb_context *context;
	struct xkb_keymap *keymap;
	struct xkb_rule_names names;
	struct xkb_state *state;

	memset(&names, 0, sizeof names);
	names.layout = layout;
	context = xkb_context_new(XKB_CONTEXT_NO_FLAGS);
	assert(context != NULL);
	keymap = xkb_keymap_new_from_names(context, &names,
		XKB_KEYMAP_COMPILE_NO_FLAGS);
	assert(keymap != NULL);
	state = xkb_state_new(keymap);
	assert(state != NULL);
	xkb_keymap_unref(keymap);
	xkb_context_unref(context);
	return state;
}

static void
checkkeys(void)
{
	struct xkb_state *state;

	state = keystate("de,ru");
	assert(keymaplookup(state, 38, 0) == XKB_KEY_a);
	assert(keymaplookup(state, 38, ShiftMask) == XKB_KEY_A);
	assert(keymaplookup(state, 38, LockMask) == XKB_KEY_A);
	assert(keymaplookup(state, 38, LockMask|ShiftMask) == XKB_KEY_a);
	assert(keymaplookup(state, 26, Mod5Mask) == XKB_KEY_EuroSign);
	assert(keymaplookup(state, 26, Group1) == XKB_KEY_Cyrillic_u);
	assert(keymaplookup(state, 87, 0) == XKB_KEY_KP_End);
	assert(keymaplookup(state, 87, Mod2Mask) == XKB_KEY_KP_1);
	xkb_state_unref(state);
	assert(keymaplookup(NULL, 38, 0) == XKB_KEY_NoSymbol);
}

static void
checktext(const char *s)
{
	char *ct, *utf8;
	size_t clen, len, ulen;

	len = strlen(s);
	ct = ximcompound(s, len, &clen);
	assert(ct != NULL);
	utf8 = xcb_compound_text_to_utf8(ct, clen, &ulen);
	assert(utf8 != NULL);
	assert(ulen == len);
	assert(memcmp(utf8, s, len) == 0);
	free(utf8);
	free(ct);
}

static void
checkutf8run(void)
{
	static const char s[] = "😀";
	char *ct;
	size_t n;

	ct = ximcompound(s, sizeof s - 1, &n);
	assert(ct != NULL);
	assert(n >= 6);
	assert(memcmp(ct, "\033%G", 3) == 0);
	assert(memcmp(ct+n-3, "\033%@", 3) == 0);
	free(ct);
}

static void
checkcorpus(void)
{
	static const char *text[] = {
		"한글",
		"𠀋",
		"👩‍💻",
	};
	size_t i;

	for(i = 0; i < sizeof text / sizeof text[0]; i++)
		checktext(text[i]);
}

int
main(void)
{
	xcb_compound_text_init();

	checkkeys();
	checkcorpus();
	checktext("A😀한");
	checkutf8run();
	return 0;
}