#include <stdio.h>
#include <assert.h>
#include <string.h>
#include <stdlib.h>
#include <xcb/xcb.h>

#include <xcb/xcb_wm.h>
#include <X11/XKBlib.h>

#include "i3.h"
#include "debug.h"
#include "table.h"
#include "layout.h"
#include "commands.h"
#include "data.h"
#include "font.h"

static void set_focus(xcb_connection_t *conn, Client *client) {
	/* Update container */
	Client *old_client = client->container->currently_focused;
	client->container->currently_focused = client;

	current_col = client->container->col;
	current_row = client->container->row;

	/* Set focus to the entered window, and flush xcb buffer immediately */
	xcb_set_input_focus(conn, XCB_INPUT_FOCUS_NONE, client->child, XCB_CURRENT_TIME);
	/* Update last/current client’s titlebar */
	if (old_client != NULL)
		decorate_window(conn, old_client);
	decorate_window(conn, client);
	xcb_flush(conn);
}


/*
 * Due to bindings like Mode_switch + <a>, we need to bind some keys in XCB_GRAB_MODE_SYNC.
 * Therefore, we just replay all key presses.
 *
 */
int handle_key_release(void *ignored, xcb_connection_t *conn, xcb_key_release_event_t *event) {
	printf("got key release, just passing\n");
	xcb_allow_events(conn, XCB_ALLOW_REPLAY_KEYBOARD, event->time);
	xcb_flush(conn);
	return 1;
}

/*
 * There was a key press. We lookup the key symbol and see if there are any bindings
 * on that. This allows to do things like binding special characters (think of ä) to
 * functions to get one more modifier while not losing AltGr :-)
 * TODO: this description needs to be more understandable
 *
 */
int handle_key_press(void *ignored, xcb_connection_t *conn, xcb_key_press_event_t *event) {
	printf("Keypress %d\n", event->detail);

	/* We need to get the keysym group (There are group 1 to group 4, each holding
	   two keysyms (without shift and with shift) using Xkb because X fails to
	   provide them reliably (it works in Xephyr, it does not in real X) */
	XkbStateRec state;
	if (XkbGetState(xkbdpy, XkbUseCoreKbd, &state) == Success && (state.group+1) == 2)
		event->state |= 0x2;

	printf("state %d\n", event->state);

	/* Find the binding */
	/* TODO: event->state durch eine bitmask filtern und dann direkt vergleichen */
	Binding *bind, *best_match = TAILQ_END(&bindings);
	TAILQ_FOREACH(bind, &bindings, bindings) {
		if (bind->keycode == event->detail &&
			(bind->mods & event->state) == bind->mods) {
			if (best_match == TAILQ_END(&bindings) ||
				bind->mods > best_match->mods)
				best_match = bind;
		}
	}

	/* No match? Then it was an actively grabbed key, that is with Mode_switch, and
	   the user did not press Mode_switch, so just pass it… */
	if (best_match == TAILQ_END(&bindings)) {
		xcb_allow_events(conn, ReplayKeyboard, event->time);
		xcb_flush(conn);
		return 1;
	}

	if (event->state & 0x2) {
		printf("that's mode_switch\n");
		parse_command(conn, best_match->command);
		printf("ok, hiding this event.\n");
		xcb_allow_events(conn, SyncKeyboard, event->time);
		xcb_flush(conn);
		return 1;
	}

	parse_command(conn, best_match->command);
	return 1;
}


/*
 * When the user moves the mouse pointer onto a window, this callback gets called.
 *
 */
int handle_enter_notify(void *ignored, xcb_connection_t *conn, xcb_enter_notify_event_t *event) {
	printf("enter_notify\n");

	/* This was either a focus for a client’s parent (= titlebar)… */
	Client *client = table_get(byParent, event->event);
	/* …or the client itself */
	if (client == NULL)
		client = table_get(byChild, event->event);

	/* If not, then this event is not interesting. This should not happen */
	if (client == NULL) {
		printf("DEBUG: Uninteresting enter_notify-event?\n");
		return 1;
	}

	set_focus(conn, client);

	return 1;
}

int handle_button_press(void *ignored, xcb_connection_t *conn, xcb_button_press_event_t *event) {
	printf("button press!\n");
	/* This was either a focus for a client’s parent (= titlebar)… */
	Client *client = table_get(byChild, event->event);
	if (client == NULL)
		client = table_get(byParent, event->event);
	if (client == NULL)
		return 1;

	xcb_window_t root = xcb_setup_roots_iterator(xcb_get_setup(conn)).data->root;
	xcb_screen_t *root_screen = xcb_setup_roots_iterator(xcb_get_setup(conn)).data;

	/* Set focus in any case */
	set_focus(conn, client);

	/* Let’s see if this was on the borders (= resize). If not, we’re done */
	i3Font *font = load_font(conn, pattern);
	printf("press button on x=%d, y=%d\n", event->event_x, event->event_y);
	if (event->event_y <= (font->height + 2))
		return 1;

	printf("that was resize\n");

	/* Open a new window, the resizebar. Grab the pointer and move the window around
	   as the user moves the pointer. */


	/* TODO: the whole logic is missing. this is just a proof of concept */
	xcb_window_t grabwin = xcb_generate_id(conn);

	uint32_t mask = 0;
	uint32_t values[3];

	xcb_create_window(conn,
			0,
			grabwin,
			root,
			0, /* x */
			0, /* y */
			root_screen->width_in_pixels, /* width */
			root_screen->height_in_pixels, /* height */
			/* border_width */ 0,
			XCB_WINDOW_CLASS_INPUT_ONLY,
			root_screen->root_visual,
			0,
			values);

	/* Map the window on the screen (= make it visible) */
	xcb_map_window(conn, grabwin);

	xcb_window_t helpwin = xcb_generate_id(conn);

	mask = XCB_CW_BACK_PIXEL;
	values[0] = root_screen->white_pixel;
	xcb_create_window(conn, root_screen->root_depth, helpwin, root,
			event->root_x,
			0,
			5,
			root_screen->height_in_pixels,
			/* bordor */ 0,
			XCB_WINDOW_CLASS_INPUT_OUTPUT,
			root_screen->root_visual,
			mask,
			values);

	xcb_map_window(conn, helpwin);
	xcb_circulate_window(conn, XCB_CIRCULATE_RAISE_LOWEST, helpwin);

	xcb_grab_pointer(conn, false, root, XCB_EVENT_MASK_BUTTON_RELEASE | XCB_EVENT_MASK_POINTER_MOTION,
			XCB_GRAB_MODE_ASYNC, XCB_GRAB_MODE_ASYNC, grabwin, XCB_NONE, XCB_CURRENT_TIME);

	xcb_flush(conn);

	xcb_generic_event_t *inside_event;
	/* I’ve always wanted to have my own eventhandler… */
	while ((inside_event = xcb_wait_for_event(conn))) {
		/* Same as get_event_handler in xcb */
		int nr = inside_event->response_type;
		if (nr == 0) {
			handle_event(NULL, conn, inside_event);
			continue;
		}
		assert(nr < 256);
		nr &= XCB_EVENT_RESPONSE_TYPE_MASK;
		assert(nr >= 2);

		/* Check if we need to escape this loop… */
		if (nr == XCB_BUTTON_RELEASE)
			break;

		switch (nr) {
			case XCB_MOTION_NOTIFY:
				values[0] = ((xcb_motion_notify_event_t*)inside_event)->root_x;
				xcb_configure_window(conn, helpwin, XCB_CONFIG_WINDOW_X, values);
				xcb_flush(conn);
				break;
			case XCB_EXPOSE:
				/* Use original handler */
				xcb_event_handle(&evenths, inside_event);
				break;
			default:
				printf("Ignoring event of type %d\n", nr);
				break;
		}
		printf("---\n");
		free(inside_event);
	}

	xcb_ungrab_pointer(conn, XCB_CURRENT_TIME);
	xcb_destroy_window(conn, helpwin);
	xcb_destroy_window(conn, grabwin);
	xcb_flush(conn);

	return 1;
}

int handle_map_notify_event(void *prophs, xcb_connection_t *conn, xcb_map_notify_event_t *event) {
	window_attributes_t wa = { TAG_VALUE };
	wa.u.override_redirect = event->override_redirect;
	printf("MapNotify for 0x%08x.\n", event->window);
	manage_window(prophs, conn, event->window, wa);
	return 1;
}

/*
 * Our window decorations were unmapped. That means, the window will be killed now,
 * so we better clean up before.
 *
 */
int handle_unmap_notify_event(void *data, xcb_connection_t *c, xcb_unmap_notify_event_t *e) {
	Client *client = table_remove(byChild, e->event);
	xcb_window_t root;
	printf("UnmapNotify for 0x%08x (received from 0x%08x): ", e->window, e->event);
	if(!client)
	{
		printf("not a managed window. Ignoring.\n");
		return 0;
	}

	int rows, cols;
	Client *con_client;
	/* TODO: clear this up */
	for (cols = 0; cols < c_ws->cols; cols++)
		for (rows = 0; rows < c_ws->rows; rows++)
			CIRCLEQ_FOREACH(con_client, &(CUR_TABLE[cols][rows]->clients), clients)
				if (con_client == client) {
					printf("removing from container\n");
					if (client->container->currently_focused == client)
						client->container->currently_focused = NULL;
					CIRCLEQ_REMOVE(&(CUR_TABLE[cols][rows]->clients), con_client, clients);
					break;
				}



	root = xcb_setup_roots_iterator(xcb_get_setup(c)).data->root;
	printf("child of 0x%08x.\n", client->frame);
	xcb_reparent_window(c, client->child, root, 0, 0);
	xcb_destroy_window(c, client->frame);
	xcb_flush(c);
	table_remove(byParent, client->frame);
	free(client);

	render_layout(c);

	return 1;
}

/*
 * Called when a window changes its title
 *
 */
int handle_windowname_change(void *data, xcb_connection_t *conn, uint8_t state,
				xcb_window_t window, xcb_atom_t atom, xcb_get_property_reply_t *prop) {
	printf("window's name changed.\n");
	Client *client = table_get(byChild, window);
	if (client == NULL)
		return 1;

	client->name_len = xcb_get_property_value_length(prop);
	client->name = malloc(client->name_len);
	strncpy(client->name, xcb_get_property_value(prop), client->name_len);
	printf("rename to \"%.*s\".\n", client->name_len, client->name);

	decorate_window(conn, client);
	xcb_flush(conn);

	return 1;
}

/*
 * Expose event means we should redraw our windows (= title bar)
 *
 */
int handle_expose_event(void *data, xcb_connection_t *conn, xcb_expose_event_t *e) {
	printf("handle_expose_event()\n");
	Client *client = table_get(byParent, e->window);
	if(!client || e->count != 0)
		return 1;
	decorate_window(conn, client);
	return 1;
}