%{
#include <stdio.h>
#include "calculator.h"
int yylex   (void);
int yyerror (char *);
%}
%language "C"
%union {
  char *             svalue;
  double             dvalue;
  class Expression * evalue;
}

%token          ENDLINE
%token          DOUBLE
%token          INTEGER
%token          MATHPI
%token          FCESIN
%token          FCECOS
%token          FCEEXP
%token          FCELOG
%token          IDENT
%token          TEXT
%left           '+' '-'
%left           '*' '/'
%left           '^'

%type <svalue> ENDLINE DOUBLE INTEGER IDENT line lines
%type <evalue> expr
%type <dvalue> constnt
%start input
%%

input:  /* empty */
        | lines
        ;
lines:  line
        | lines line
        ;
line:   ENDLINE
        | IDENT '=' expr ENDLINE                   { addVariable ($1, $3->eval());                      free ($1); }
        | IDENT '=' expr ',' expr ',' expr ENDLINE { addRange ($1, $3->eval(), $5->eval(), $7->eval()); free ($1); }
        | expr  ENDLINE { addExpression ($1);       }
        | error ENDLINE { printf ("what:%s\n", $$); }
        ;
constnt:  DOUBLE        { $$ = str_to_double ($1); free ($1); }
        | INTEGER       { $$ = str_to_long   ($1); free ($1); }
        | MATHPI        { $$ = 3.14159265359; }
        ;
expr:     constnt       { $$ = new Constant ($1); }
        | IDENT         { $$ = new Variable ($1);  free ($1);    }
        | '-' expr      { $$ = new Unary  ($2,     UNARY_MINUS); }
        | expr '+' expr { $$ = new Binary ($1, $3, BINARY_PLUS); }
        | expr '-' expr { $$ = new Binary ($1, $3, BINARY_MINUS);}
        | expr '*' expr { $$ = new Binary ($1, $3, BINARY_MULT); }
        | expr '/' expr { $$ = new Binary ($1, $3, BINARY_DIV);  }
        | expr '^' expr { $$ = new Binary ($1, $3, BINARY_POW);  }
        | '(' expr ')'  { $$ = $2; }
        | FCESIN '(' expr ')' { $$ = new Unary  ($3, UNARY_SIN); }
        | FCECOS '(' expr ')' { $$ = new Unary  ($3, UNARY_COS); }
        | FCEEXP '(' expr ')' { $$ = new Unary  ($3, UNARY_EXP); }
        | FCELOG '(' expr ')' { $$ = new Unary  ($3, UNARY_LOG); }
        ;
%%
int yyerror(char * err) {
  printf("Error:\"%s\"\n", err);
  return 0;
}