/* retoor <retoor@molodetz.nl> */
#ifndef LOREX_AST_H
#define LOREX_AST_H

#include <stdbool.h>
#include <stddef.h>

typedef enum {
    AST_CHAR,
    AST_DOT,
    AST_CONCAT,
    AST_ALTER,
    AST_STAR,
    AST_PLUS,
    AST_QUESTION,
    AST_GROUP,
    AST_ANCHOR_START,
    AST_ANCHOR_END,
    AST_BRACKET,
    AST_QUANTIFIER,
    AST_CLASS_DIGIT,
    AST_CLASS_WORD,
    AST_CLASS_SPACE,
    AST_CLASS_NDIGIT,
    AST_CLASS_NWORD,
    AST_CLASS_NSPACE
} ast_type_t;

typedef struct {
    char start;
    char end;
} char_range_t;

typedef struct {
    char_range_t *ranges;
    size_t count;
    size_t capacity;
    bool negated;
    unsigned char bitmap[32];
    bool bitmap_valid;
} bracket_class_t;

typedef struct {
    int min;
    int max;
    bool greedy;
} quantifier_t;

typedef struct ast_node ast_node_t;

struct ast_node {
    ast_type_t type;
    char value;
    ast_node_t *left;
    ast_node_t *right;
    int group_id;
    bracket_class_t *bracket;
    quantifier_t quant;
};

ast_node_t *ast_create_char(char c);
ast_node_t *ast_create_dot(void);
ast_node_t *ast_create_concat(ast_node_t *left, ast_node_t *right);
ast_node_t *ast_create_alter(ast_node_t *left, ast_node_t *right);
ast_node_t *ast_create_star(ast_node_t *child, bool greedy);
ast_node_t *ast_create_plus(ast_node_t *child, bool greedy);
ast_node_t *ast_create_question(ast_node_t *child, bool greedy);
ast_node_t *ast_create_group(ast_node_t *child, int group_id);
ast_node_t *ast_create_anchor_start(void);
ast_node_t *ast_create_anchor_end(void);
ast_node_t *ast_create_bracket(bracket_class_t *bracket);
ast_node_t *ast_create_quantifier(ast_node_t *child, int min, int max, bool greedy);
ast_node_t *ast_create_class(ast_type_t type);
void ast_free(ast_node_t *node);

bracket_class_t *bracket_create(void);
void bracket_add_char(bracket_class_t *bracket, char c);
void bracket_add_range(bracket_class_t *bracket, char start, char end);
void bracket_free(bracket_class_t *bracket);
bool bracket_matches(bracket_class_t *bracket, char c);

#endif