%{
#include "C:\Users\user\Desktop\УЧЕБА\6_СЕМ\КОМПИЛЯТОРЫ\flex_bison_test\analyzers\polynomials\poly_calc\poly_calc.h"
#include <stdio.h>
#include <stdlib.h>

void yyerror(const char *s);
int yylex();

// Объявляем внешнюю переменную для файла
extern FILE *yyin;
extern char allowed_variable;
%}

%union {
    Polynomial poly;
}

%token <poly> NUMBER VARIABLE
%type <poly> expr

%left '+' '-'
%left '*' '/'
%left UMINUS
%right '^'

%%
input:
      | input expr { 
            printf("Result: ");
            sort_polynomial(&$2);
            print_polynomial(&$2, allowed_variable);
            free_polynomial(&$2);
        }
      ;

expr:    NUMBER         { $$ = $1; }
      | VARIABLE        { $$ = $1; }
      | '-' expr %prec UMINUS { 
            $$ = copy_poly(&$2);
            for (int i = 0; i < $$.size; i++) {
                $$.terms[i].coefficient *= -1;
            }
            free_polynomial(&$2);
        }
      | expr '+' expr    { 
            $$ = add_polynomials(&$1, &$3);
            free_polynomial(&$1);
            free_polynomial(&$3);
        }
      | expr '-' expr    { 
            $$ = sub_polynomials(&$1, &$3);
            free_polynomial(&$1);
            free_polynomial(&$3);
        }
      | expr '*' expr    { 
            $$ = mul_polynomials(&$1, &$3);
            free_polynomial(&$1);
            free_polynomial(&$3);
        }
      | expr '^' expr    { 
            if ($3.size != 1 || $3.terms[0].exponent != 0) {
                yyerror("Exponent must be constant");
                YYERROR;
            }
            int degree = $3.terms[0].coefficient;
            if (degree < 0) {
                yyerror("Negative exponents not supported");
                YYERROR;
            }
            $$ = deg_poly(&$1, degree);
            free_polynomial(&$1);
            free_polynomial(&$3);
        }
      | '(' expr ')'     { $$ = $2; }
      ;
%%

void yyerror(const char *s) {
    fprintf(stderr, "ERROR: %s\n", s);
}

int main(int argc, char *argv[]) {
    if (argc < 2) {
        fprintf(stderr, "Usage: %s input_file\n", argv[0]);
        return 1;
    }

    FILE *input_file = fopen(argv[1], "r");
    if (!input_file) {
        perror("Error opening file");
        return 1;
    }

    // Устанавливаем файл как вход для лексера
    yyin = input_file;

    yyparse();

    fclose(input_file);
    return 0;
}