/*
 * Copyright (c) 2023 : Ognjen 'xolatile' Milan Robovic
 *
 * Xyntax 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 XYNTAX_SOURCE
#define XYNTAX_SOURCE

#include <xolatile/xyntax.h>

int      syntax_count   = 0;
int    * syntax_enrange = NULL;
int    * syntax_derange = NULL;
char * * syntax_begin   = NULL;
char * * syntax_end     = NULL;
char   * syntax_escape  = NULL;
int    * syntax_colour  = NULL;
int    * syntax_effect  = NULL;

static int compare_character_array (char character, char * character_array, int count) {
	int i = 0;

	do {
		if (character == character_array [i]) {
			return (1);
		}
	} while (++i != count);

	return (0);
}

int syntax_define (int enrange, int derange, char * begin, char * end, char escape, int colour, int effect) {
	fatal_failure (begin == NULL, "syntax_define: Begin string is null pointer.");
	fatal_failure (end   == NULL, "syntax_define: End string is null pointer.");

	++syntax_count;

	syntax_enrange = reallocate (syntax_enrange, syntax_count * (int) sizeof (* syntax_enrange));
	syntax_derange = reallocate (syntax_derange, syntax_count * (int) sizeof (* syntax_derange));
	syntax_begin   = reallocate (syntax_begin,   syntax_count * (int) sizeof (* syntax_begin));
	syntax_end     = reallocate (syntax_end,     syntax_count * (int) sizeof (* syntax_end));
	syntax_escape  = reallocate (syntax_escape,  syntax_count * (int) sizeof (* syntax_escape));
	syntax_colour  = reallocate (syntax_colour,  syntax_count * (int) sizeof (* syntax_colour));
	syntax_effect  = reallocate (syntax_effect,  syntax_count * (int) sizeof (* syntax_effect));

	syntax_begin [syntax_count - 1] = allocate ((string_length (begin) + 1) * (int) sizeof (* * syntax_begin));
	syntax_end   [syntax_count - 1] = allocate ((string_length (end)   + 1) * (int) sizeof (* * syntax_end));

	syntax_enrange [syntax_count - 1] = enrange;
	syntax_derange [syntax_count - 1] = derange;
	syntax_escape  [syntax_count - 1] = escape;
	syntax_colour  [syntax_count - 1] = colour;
	syntax_effect  [syntax_count - 1] = effect;

	string_copy (syntax_begin [syntax_count - 1], begin);
	string_copy (syntax_end   [syntax_count - 1], end);

	return (syntax_count - 1);
}

int syntax_select (char * string, int * length) {
	int offset = 0;
	int select = 0;

	fatal_failure (string == NULL, "syntax_select: String is null.");
	fatal_failure (length == NULL, "syntax_select: Length is null.");

	do {
		if (syntax_enrange [select] == 0) {
			if (string_compare_limit (string, syntax_begin [select], string_length (syntax_begin [select])) != 0) {
				if (syntax_derange [select] == 0) {
					break;
				} else {
					if (compare_character_array (string [string_length (syntax_begin [select])], syntax_end [select], string_length (syntax_end [select]))) {
						break;
					}
				}
			}
		} else {
			int subset = 0;
			do {
				if (string [offset] == syntax_begin [select] [subset]) {
					goto selected;
				}
			} while (++subset != (int) string_length (syntax_begin [select]));
		}
	} while (++select != syntax_count);

	selected:

	if (select == syntax_count) { /* Undefined symbol. */
		* length = 1;
		return (0);
	}

	do {
		++offset;

		if (string [offset] == syntax_escape [select]) {
			++offset;
			continue;
		}

		if (syntax_derange [select] == 0) {
			if (string_compare_limit (& string [offset], syntax_end [select], string_length (syntax_end [select]))) {
				* length = offset + string_length (syntax_end [select]);
				return (select);
			}
		} else {
			int subset = 0;
			if (string_compare (syntax_end [select], "") == 0) {
				break;
			} do {
				if (string [offset] == syntax_end [select] [subset]) {
					* length = offset;
					return (select);
				}
			} while (++subset != (int) string_length (syntax_end [select]));
		}
	} while (string [offset - 1] != '\0');

	return (select);
}

void syntax_delete (void) {
	--syntax_count;

	do {
		syntax_begin [syntax_count] = deallocate (syntax_begin [syntax_count]);
		syntax_end   [syntax_count] = deallocate (syntax_end   [syntax_count]);
	} while (--syntax_count != -1);

	syntax_enrange = deallocate (syntax_enrange);
	syntax_derange = deallocate (syntax_derange);
	syntax_begin   = deallocate (syntax_begin);
	syntax_end     = deallocate (syntax_end);
	syntax_escape  = deallocate (syntax_escape);
	syntax_colour  = deallocate (syntax_colour);
	syntax_effect  = deallocate (syntax_effect);
}

#endif