/* Calcite, src/user-apps/shell/runtime.h
 * Copyright 2026 Benji Dial
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program. If not, see <https://www.gnu.org/licenses/>.
 */

#pragma once

void save_return_stack();
//and_call should not return.
[[noreturn]] void restore_return_stack(void (*and_call)());

void create_data_stack();
void push(int value);
int pop();

int *get_data_stack_pointer();
int *get_data_stack_top();

//null-terminated. not copied.
void set_input(const char *buffer);

//length_out is set to 0 on eof. skips all whitespace before and up to one character after.
void read_input_word(const char **start_out, int *length_out);

//errors on eof before end. skips end. end not included in length.
void read_until(char end, const char **start_out, int *length_out);

struct word {
  int name_length;
  const char *name;
  void (*interpret)();
  void (*compile)();
  const struct word *previous;
};

#define INTERPRET_ERROR ((void (*)())-1)

#define COMPILE_ERROR ((void (*)())-1)
#define COMPILE_EMIT_CALL ((void (*)())-2)

//returns 0 if not found. name does not need to be null-terminated.
const struct word *look_up_word(int name_length, const char *name);
struct word *new_word();

void print_all_words();

[[noreturn]] void error(const char *message);

extern int compiling;

[[noreturn]] void main_loop();