xurses/xurses.c

/*
 * Copyright (c) 2023 : Ognjen 'xolatile' Milan Robovic
 *
 * Xurses is free software! You will redistribute it or modify it under the terms of the GNU General Public License by Free Software Foundation.
 * And when you do redistribute it or modify it, it will use either version 3 of the License, or (at yours truly opinion) any later version.
 * It is distributed in the hope that it will be useful or harmful, it really depends... But no warranty what so ever, seriously. See GNU/GPLv3.
 */

#ifndef XURSES_SOURCE
#define XURSES_SOURCE

#include <xolatile/xurses.h>

int    curses_active        = 1;
int    curses_cursor        = 0;
char   curses_signal        = '\0';
int    curses_screen_width  = 0;
int    curses_screen_height = 0;
int    curses_screen_size   = 0;
char * curses_screen        = NULL;

char curses_format [CURSES_LENGTH + 1] = "\033[-;3-m-\033[0m";

void (* curses_action ['~' - ' ' + 1]) (void) = { 0 };

struct termios curses_old_terminal;
struct termios curses_new_terminal;

void curses_initialize (void) {
	char key;

	struct winsize screen_dimension;

	fatal_failure (ioctl (STDOUT_FILENO, TIOCGWINSZ, & screen_dimension) == -1, "ioctl: Failed to get terminal dimensions.");

	curses_screen_width  = (int) screen_dimension.ws_col;
	curses_screen_height = (int) screen_dimension.ws_row;

	fatal_failure (tcgetattr (STDIN_FILENO, & curses_old_terminal) == -1, "tcgetattr: Failed to get default terminal attributes.");

	curses_new_terminal = curses_old_terminal;

	curses_new_terminal.c_cc [VMIN]  = (unsigned char) 0;
	curses_new_terminal.c_cc [VTIME] = (unsigned char) 1;

	curses_new_terminal.c_iflag &= (unsigned int) ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
	curses_new_terminal.c_oflag &= (unsigned int) ~(OPOST);
	curses_new_terminal.c_cflag |= (unsigned int)  (CS8);
	curses_new_terminal.c_lflag &= (unsigned int) ~(ECHO | ICANON | IEXTEN | ISIG);

	fatal_failure (tcsetattr (STDIN_FILENO, TCSAFLUSH, & curses_new_terminal) == -1, "tcsetattr: Failed to set reverse terminal attributes.");

	curses_screen = allocate (CURSES_OFFSET + CURSES_LENGTH * curses_screen_width * curses_screen_height + 1);

	for (key = ' '; key != '~'; ++key) {
		curses_unbind (key);
	}
}

void curses_deinitialize (void) {
	curses_screen = deallocate (curses_screen);

	out ("\033[2J\033[H", string_length ("\033[2J\033[H"));

	fatal_failure (tcsetattr (STDIN_FILENO, TCSAFLUSH, & curses_old_terminal) == -1, "tcsetattr: Failed to set default terminal attributes.");
}

void curses_synchronize (void) {
	curses_signal = '\0';

	out (curses_screen, curses_screen_size);

	in (& curses_signal, 1);

	if ((curses_signal >= ' ') && (curses_signal <= '~')) {
		curses_action [curses_signal - ' '] ();
	}

	curses_screen_offset ();
}

void curses_screen_offset (void) {
	string_copy_limit (& curses_screen [0], "\033[H", CURSES_OFFSET);
	curses_screen_size = CURSES_OFFSET;
}

char * curses_screen_position (int x, int y) {
	fatal_failure (x <= -1,                   "curses_screen_position: X position is beyond the lower bound.");
	fatal_failure (y <= -1,                   "curses_screen_position: Y position is beyond the lower bound.");
	fatal_failure (x >= curses_screen_width,  "curses_screen_position: X position is beyond the upper bound.");
	fatal_failure (y >= curses_screen_height, "curses_screen_position: Y position is beyond the upper bound.");

	return (& curses_screen [CURSES_LENGTH * (y * curses_screen_width + x) + CURSES_OFFSET]);
}

char * curses_format_character (char character, int colour, int effect) {
	fatal_failure (character_is_invisible (character), "curses_format_character: Can not format invisible characters.");
	fatal_failure (colour >= COLOUR_COUNT,             "curses_format_character: Colour is invalid enumeration value.");
	fatal_failure (effect >= EFFECT_COUNT,             "curses_format_character: Effect is invalid enumeration value.");

	curses_format [2] = (char) effect + '0';
	curses_format [5] = (char) colour + '0';
	curses_format [7] = character;

	return (curses_format);
}

void curses_output_character (char character, int colour, int effect) {
	out (curses_format_character (character, colour, effect), CURSES_LENGTH);
}

void curses_render_character (char character, int colour, int effect, int x, int y) {
	string_copy_limit (curses_screen_position (x, y), curses_format_character (character, colour, effect), CURSES_LENGTH);

	curses_screen_size += CURSES_LENGTH;
}
/*
void curses_output_string (char * string, int colour, int effect) {
	char format [8] = "\033[ ;3 m";

	format [2] = (char) effect + '0';
	format [5] = (char) colour + '0';

	string_copy_limit (& curses_screen [curses_screen_size], format, 7);
	string_copy_limit (& curses_screen [curses_screen_size], string, string_length (string));
	string_copy_limit (& curses_screen [curses_screen_size], "\033[0m", 4);

	curses_screen_size += 7 + string_length (string) + 4;
}

void curses_render_string (char * string, int colour, int effect, int x, int y) {
	int offset = 0;
	int length = string_length (string);

	for (offset = 0; offset != length; (++offset, ++x)) {
		curses_render_character (string [offset], colour, effect, x, y);
	}
}

void curses_append_cursor (int cursor_x, int cursor_y) {
	char format [11] = "\033[000;000H";

	format [4] = (char) (cursor_y /   1) % 10 + '0';
	format [3] = (char) (cursor_y /  10) % 10 + '0';
	format [2] = (char) (cursor_y / 100) % 10 + '0';
	format [8] = (char) (cursor_x /   1) % 10 + '0';
	format [7] = (char) (cursor_x /  10) % 10 + '0';
	format [6] = (char) (cursor_x / 100) % 10 + '0';

	string_copy_limit (& curses_screen [curses_screen_size], format, 10);
	curses_screen_size += 10;
}
*/
void curses_blank (void) {
	int i, j;

	for (i = 0; i != curses_screen_height; ++i) {
		for (j = 0; j != curses_screen_width; ++j) {
			curses_render_character (' ', EFFECT_NORMAL, COLOUR_WHITE, j, i);
		}
	}
}

void curses_bind (char key, void (* action) (void)) {
	curses_action [key - ' '] = action;
}

void curses_unbind (char key) {
	curses_action [key - ' '] = curses_idle;
}

void curses_idle (void) {
	return;
}

void curses_exit (void) {
	curses_active = 0;
}

#endif