#ifndef _AST_NODE_H_
#define _AST_NODE_H_

#include <ivy/lang/ast.h>
#include <ivy/lang/lex.h>

struct parser_state;

#define PARSE_RESULT(status, flags) \
        ((struct token_parse_result) { .r_status = (status), .r_flags = (flags) })

#define __TOK_PARSER_INDEX(x) ((x) - __IVY_TOK_INDEX_BASE)
#define __SYM_PARSER_INDEX(x) ((x) - __IVY_SYM_INDEX_BASE)
#define __KW_PARSER_INDEX(x) ((x) - __IVY_KW_INDEX_BASE)

#define __TOK_PARSER_FALLBACK_INDEX IVY_TOK_NONE
#define __SYM_PARSER_FALLBACK_INDEX IVY_SYM_NONE
#define __KW_PARSER_FALLBACK_INDEX IVY_KW_NONE

#define TOK_PARSER(id, func) [__TOK_PARSER_INDEX(IVY_TOK_##id)] = func
#define SYM_PARSER(id, func) [__SYM_PARSER_INDEX(IVY_SYM_##id)] = func
#define KW_PARSER(id, func) [__KW_PARSER_INDEX(IVY_KW_##id)] = func

#define TOK_PARSER_FALLBACK(func) [__TOK_PARSER_FALLBACK_INDEX] = func
#define SYM_PARSER_FALLBACK(func) [__SYM_PARSER_FALLBACK_INDEX] = func
#define KW_PARSER_FALLBACK(func) [__KW_PARSER_FALLBACK_INDEX] = func

enum token_parse_flags {
        PARSE_REPEAT_TOKEN = 0x01u,
};

enum token_expr_type {
        TOK_EXPR_NONE = 0,
        TOK_EXPR_BEGIN,
        TOK_EXPR_ANY,
};

struct token_parse_result {
        enum ivy_status r_status;
        enum token_parse_flags r_flags;
};

typedef struct token_parse_result (*token_parse_function)(
    struct ivy_parser*, struct ivy_token*);

struct ast_node_type {
        enum ivy_status (*n_add_child)(
            struct parser_state*, struct ivy_ast_node *);
        void (*n_to_string)(struct ivy_ast_node *, struct b_string *);
        void (*n_init_state)(struct ivy_parser *, struct parser_state *, uintptr_t);
        void (*n_collect_children)(
            struct ivy_ast_node*, struct ivy_ast_node_iterator *);

        size_t n_state_size;
        size_t n_node_size;

        token_parse_function n_token_parsers[__TOK_PARSER_INDEX(__IVY_TOK_INDEX_LIMIT)];
        token_parse_function n_keyword_parsers[__KW_PARSER_INDEX(__IVY_KW_INDEX_LIMIT)];
        token_parse_function n_symbol_parsers[__SYM_PARSER_INDEX(__IVY_SYM_INDEX_LIMIT)];

        struct {
                token_parse_function expr_begin;
                token_parse_function expr_other;
                token_parse_function expr_all;
        } n_expr_parser;
};

extern const struct ast_node_type* get_ast_node_type(enum ivy_ast_node_type type);
extern token_parse_function get_token_parser(
    struct ivy_ast_node* context, struct ivy_token* tok);
extern enum token_expr_type get_token_expr_type(struct ivy_token* tok);
extern struct ivy_ast_node* ast_node_create(enum ivy_ast_node_type type);
extern enum ivy_status ast_node_add_child(
    struct ivy_ast_node* parent, struct ivy_ast_node* child);

#endif