#ifndef CALCULATOR_H_
#define CALCULATOR_H_
#include <assert.h>
#include <cstdint>
#include <cstdlib>
#include <exception>
#include <iomanip>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <string>

#define INFO 0
#define ERROR 1
#define PANIC 2

#define elog(level, format, ...)                                               \
  do {                                                                         \
    char buffer[1024];                                                         \
    snprintf(buffer, 1024, format " [%s:%d]\n", ##__VA_ARGS__, __FILE__,       \
             __LINE__);                                                        \
    fprintf(stderr, buffer);                                                   \
    if (level == ERROR) {                                                      \
      throw std::runtime_error(buffer);                                        \
    }                                                                          \
    if (level == PANIC) {                                                      \
      assert(0);                                                               \
    }                                                                          \
  } while (0)

#define VALUE_INTEGER 'i'
#define VALUE_NUMBER 'n'

#define EXPR_VALUE    1
#define EXPR_NEGATE   2
#define EXPR_ADD      3
#define EXPR_SUB      4
#define EXPR_MUL      5
#define EXPR_DIV      6
#define EXPR_ABS      7
#define EXPR_MAX      8

typedef struct Value {
  char value_type; /*VALUE_*/
  union {
    int64_t ingeger;
    double number;
  };
} Value;


#define IS_INTERGER(v)  (v->value_type == VALUE_INTEGER)

typedef struct Expr {
  char expr_type; /*EXPR_*/
  Value* value;
  Expr *left;
  Expr *right;
} Expr;


double value_to_number(Value* v);
std::string value_to_string(const Value *value);
Value *make_integer(int64_t ingeger);
Value *make_number(double number);
Expr* make_value_expr(Value* v);
Expr* make_neate_expr(Expr* expr);
Expr* make_add_expr(Expr* left, Expr* right);
Expr* make_sub_expr(Expr* left, Expr* right);
Expr* make_mul_expr(Expr* left, Expr* right);
Expr* make_div_expr(Expr* left, Expr* right);
Expr* make_function_expr1(const char* func_name, Expr* arg);
Expr* make_function_expr2(const char* func_name, Expr* arg1, Expr* arg2);
Value *eval_expr(Expr *expr);
Value *my_calculator(const std::string& str);

#endif