#ifndef xlesses_header
#define xlesses_header

#include <xolatile/xtandard.h>

#include <xcb/xcb.h>
#include <xcb/xcb_atom.h>
#include <xcb/xcb_image.h>

#define xlesses_font_width     (8)
#define xlesses_font_height    (8)
#define xlesses_font_tabulator (4)
/*
static void (* xlesses_action [signal_count]) (void) = { null };
*/
static xcb_connection_t * xlesses_connection = null;
static xcb_screen_t     * xlesses_screen     = null;
static xcb_window_t       xlesses_window     = 0;
static xcb_gcontext_t     xlesses_context    = 0;
static xcb_pixmap_t       xlesses_pixmap     = 0;
static xcb_image_t      * xlesses_image      = null;

static int   xlesses_active        = false;
static int   xlesses_window_width  = 0;
static int   xlesses_window_height = 0;
static int   xlesses_cursor_x      = 0;
static int   xlesses_cursor_y      = 0;
static int   xlesses_signal        = 0;
static int * xlesses_framebuffer   = null;

static void xlesses (void) {
	xlesses_framebuffer = deallocate (xlesses_framebuffer);

	xcb_free_gc        (xlesses_connection, xlesses_context);
	xcb_free_pixmap    (xlesses_connection, xlesses_pixmap);
	xcb_destroy_window (xlesses_connection, xlesses_window);
	xcb_disconnect     (xlesses_connection);
}

static int xlesses_screen_length (void) {
	return (xlesses_window_width * xlesses_window_height * (int) sizeof (* xlesses_framebuffer));
}

static void xlesses_configure (int width, int height, char * title) {
	unsigned int window_flags [2];

	if (xlesses_active == true) {
		return;
	} else {
		clean_up (xlesses);
	}

	xlesses_window_width  = width;
	xlesses_window_height = height;

	xlesses_connection = xcb_connect (null, null);

	xlesses_screen = xcb_setup_roots_iterator (xcb_get_setup (xlesses_connection)).data;

	xlesses_window  = xcb_generate_id (xlesses_connection);
	xlesses_context = xcb_generate_id (xlesses_connection);
	xlesses_pixmap  = xcb_generate_id (xlesses_connection);

	window_flags [0] = xlesses_screen->black_pixel;
	window_flags [1] = XCB_EVENT_MASK_NO_EVENT        |
	                   XCB_EVENT_MASK_EXPOSURE        |
	                   XCB_EVENT_MASK_RESIZE_REDIRECT |
	                   XCB_EVENT_MASK_KEY_RELEASE     |
	                   XCB_EVENT_MASK_KEY_PRESS       |
	                   XCB_EVENT_MASK_BUTTON_RELEASE  |
	                   XCB_EVENT_MASK_BUTTON_PRESS;

	xcb_create_window (xlesses_connection, xlesses_screen->root_depth, xlesses_window, xlesses_screen->root, 0, 0,
	                   (unsigned short int) width, (unsigned short int) height, 10, XCB_WINDOW_CLASS_INPUT_OUTPUT,
	                   xlesses_screen->root_visual, XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK, window_flags);

	xcb_map_window (xlesses_connection, xlesses_window);

	xcb_change_property (xlesses_connection, XCB_PROP_MODE_REPLACE, xlesses_window, XCB_ATOM_WM_NAME, XCB_ATOM_STRING, 8,
	                     string_length (title), title);

	xcb_create_pixmap (xlesses_connection, xlesses_screen->root_depth, xlesses_pixmap, xlesses_window, (unsigned short int) width,
	                   (unsigned short int) height);

	xcb_create_gc (xlesses_connection, xlesses_context, xlesses_pixmap, 0, null);

	xcb_flush (xlesses_connection);

	xlesses_framebuffer = allocate (xlesses_screen_length ());

	xlesses_active = true;
}

static void xlesses_synchronize (void) {
	xcb_generic_event_t * generic_event;

	if (xlesses_active == false) {
		return;
	}

	generic_event = xcb_wait_for_event (xlesses_connection);

	switch (generic_event->response_type & 127) {
		case XCB_EXPOSE: {
			xcb_flush (xlesses_connection);
		} break;
		case XCB_KEY_PRESS: {
			xlesses_signal = (int) ((xcb_key_press_event_t *) generic_event)->detail;
			if (xlesses_signal == 24) {
				xlesses_active = false;
			}
		} break;
		default: {
		} break;
	}

	generic_event = deallocate (generic_event);

	xlesses_image = xcb_image_create_native (xlesses_connection, xlesses_window_width, xlesses_window_height, XCB_IMAGE_FORMAT_Z_PIXMAP,
	                                         xlesses_screen->root_depth, xlesses_framebuffer, (unsigned int) (xlesses_screen_length ()),
	                                         (unsigned char *) xlesses_framebuffer);

	xcb_image_put (xlesses_connection, xlesses_pixmap, xlesses_context, xlesses_image, 0, 0, 0);

	xcb_image_destroy (xlesses_image);

	xcb_copy_area (xlesses_connection, xlesses_pixmap, xlesses_window, xlesses_context, 0, 0, 0, 0, xlesses_window_width,
	               xlesses_window_height);

	xlesses_framebuffer = allocate (xlesses_screen_length ());
}

static void xlesses_render_background_colour (int colour) {
	int x, y;

	if ((xlesses_framebuffer == null) || (xlesses_active == false)) {
		return;
	}

	for (y = 0; y != xlesses_window_height; ++y) {
		for (x = 0; x != xlesses_window_width; ++x) {
			xlesses_framebuffer [y * xlesses_window_width + x] = 0xff000000 | colour;
		}
	}
}

static void xlesses_render_sprite (unsigned int * sprite, int width, int height, int x, int y) {
	int offset_x, offset_y;

	if ((xlesses_framebuffer == null) || (xlesses_active == false)) {
		return;
	}

	for (offset_y = 0; offset_y != height; ++offset_y) {
		for (offset_x = 0; offset_x != width; ++offset_x) {
			xlesses_framebuffer [(y + offset_y) * xlesses_window_width + (x + offset_x)] = sprite [offset_y * width + offset_x];
		}
	}
}

static void xlesses_render_character (char character, int foreground, int background, int x, int y) {
	const unsigned long int font_code ['~' - ' ' + 2] = {
		0x0000000000000000,             0x00180018183c3c18,             0x0000000000363636,             0x006c6cfe6cfe6c6c,
		0x00187ed07c16fc30,             0x0060660c18306606,             0x00dc66b61c36361c,             0x0000000000181818,
		0x0030180c0c0c1830,             0x000c18303030180c,             0x0000187e3c7e1800,             0x000018187e181800,
		0x0c18180000000000,             0x000000007e000000,             0x0018180000000000,             0x0000060c18306000,
		0x003c666e7e76663c,             0x007e181818181c18,             0x007e0c183060663c,             0x003c66603860663c,
		0x0030307e363c3830,             0x003c6660603e067e,             0x003c66663e060c38,             0x000c0c0c1830607e,
		0x003c66663c66663c,             0x001c30607c66663c,             0x0018180018180000,             0x0c18180018180000,
		0x0030180c060c1830,             0x0000007e007e0000,             0x000c18306030180c,             0x001800181830663c,
		0x003c06765676663c,             0x006666667e66663c,             0x003e66663e66663e,             0x003c66060606663c,
		0x001e36666666361e,             0x007e06063e06067e,             0x000606063e06067e,             0x003c66667606663c,
		0x006666667e666666,             0x007e18181818187e,             0x001c36303030307c,             0x0066361e0e1e3666,
		0x007e060606060606,             0x00c6c6d6d6feeec6,             0x006666767e6e6666,             0x003c66666666663c,
		0x000606063e66663e,             0x006c36566666663c,             0x006666363e66663e,             0x003c66603c06663c,
		0x001818181818187e,             0x003c666666666666,             0x00183c6666666666,             0x00c6eefed6d6c6c6,
		0x0066663c183c6666,             0x001818183c666666,             0x007e060c1830607e,             0x003e06060606063e,
		0x00006030180c0600,             0x007c60606060607c,             0x000000000000663c,             0xffff000000000000,
		0x000000000030180c,             0x007c667c603c0000,             0x003e6666663e0606,             0x003c6606663c0000,
		0x007c6666667c6060,             0x003c067e663c0000,             0x000c0c0c3e0c0c38,             0x3c607c66667c0000,
		0x00666666663e0606,             0x003c1818181c0018,             0x0e181818181c0018,             0x0066361e36660606,
		0x003c18181818181c,             0x00c6d6d6fe6c0000,             0x00666666663e0000,             0x003c6666663c0000,
		0x06063e66663e0000,             0xe0607c66667c0000,             0x000606066e360000,             0x003e603c067c0000,
		0x00380c0c0c3e0c0c,             0x007c666666660000,             0x00183c6666660000,             0x006cfed6d6c60000,
		0x00663c183c660000,             0x3c607c6666660000,             0x007e0c18307e0000,             0x003018180e181830,
		0x0018181818181818,             0x000c18187018180c,             0x000000000062d68c,             0x0000000000000000
	};

	int offset;

	fatal_failure (xlesses_active      == false, "xlesses_render_character: Library is not active.");
	fatal_failure (xlesses_framebuffer == null, "xlesses_render_character: Framebuffer was not allocated.");

	if ((x < 0) || (x > xlesses_window_width  - xlesses_font_width  - 1)
	||  (y < 0) || (y > xlesses_window_height - xlesses_font_height - 1)) {
		return;
	}

	for (offset = 0; offset != xlesses_font_width * xlesses_font_height; ++offset) {
		int u = offset / xlesses_font_width + y;
		int v = offset % xlesses_font_width + x;

		int code = (font_code [(int) (character - ' ')] >> offset) & 1;

		xlesses_framebuffer [u * (xlesses_window_width) + v] = (code) ? foreground : background;
	}
}

static void xlesses_render_string (char * string, int foreground, int background, int x, int y) {
	int index;

	for (index = 0; string [index] != '\0'; ++index) {
		xlesses_render_character (string [index], foreground, background, x + index * xlesses_font_width, y);
	}
}

static void xlesses_render_number (int number, int foreground, int background, int x, int y) {
	xlesses_render_string (number_to_string (number), foreground, background, x, y);
}

static void xlesses_render_string_crop (char * string, int foreground, int background, int x, int y, int crop) {
	int index;

	for (index = 0; (string [index] != '\0') && (crop < index * xlesses_font_width); ++index) {
		xlesses_render_character (string [index], foreground, background, x + index * xlesses_font_width, y);
	}
}

static void xlesses_render_number_crop (int number, int foreground, int background, int x, int y, int crop) {
	xlesses_render_string_crop (number_to_string (number), foreground, background, x, y, crop);
}

#endif