#ifndef AST_H
#define AST_H

struct repeat {
	long min, max;
};

enum {
	ATOM_ALTERNATION,
	ATOM_SEQUENCE,
	ATOM_REPETITION,
	ATOM_ALPHABETIC,
	ATOM_NUMERIC,
	ATOM_UPPERCASE,
	ATOM_LOWERCASE,
	ATOM_CONTROL,
	ATOM_PUNCTUATION,
	ATOM_EVERYTHING,
	ATOM_LITERAL,

	ATOM_MAX
};

struct atom {
	int type;
	union {
		struct {
			struct repeat counts;
			struct atom *child;
		} repeat;
		const struct atom *children[2];
		const char *literal;
	} u;
};

struct atom *mkatom(const struct atom *src);
void dump_atom(const struct atom *a);

void print_regex(const struct atom *a);

extern struct atom *ast;

#endif