/*
 * Copyright (c) Camden Dixie O'Brien
 * SPDX-License-Identifier: AGPL-3.0-only
 */

#ifndef PARSER_H
#define PARSER_H

#include <stdbool.h>

typedef struct {
	bool negated;
	int count, capacity;
	char *contents;
} class_t;

typedef enum {
	QUANTIFIER_NONE,
	QUANTIFIER_ZERO_OR_MORE,
	QUANTIFIER_ONE_OR_MORE,
	QUANTIFIER_ZERO_OR_ONE,
} quantifier_t;

typedef enum {
	TERM_TYPE_WILDCARD,
	TERM_TYPE_CLASS,
	TERM_TYPE_LITERAL,
	TERM_TYPE_SUBEXPR,
} term_type_t;

struct _term;
typedef struct {
	int len, capacity;
	struct _term *contents;
} sequence_t;

typedef struct _parse_tree {
	sequence_t sequence;
	struct _parse_tree *alternative;
} parse_tree_t;

typedef struct _term {
	quantifier_t quantifier;
	term_type_t type;
	union {
		class_t class;
		char literal;
		parse_tree_t subexpr;
	};
} term_t;

int parse_expr(const char *input, int rem, parse_tree_t *out);
void parse_tree_free_children(parse_tree_t *t);

#endif