/*  G-Cows - scripting language for creation of web sites
    Copyright (C) 2002, 2003, 2004, 2005, 2006 Andrea Sozzi

This file is part of G-Cows.

G-Cows 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 2, or (at your option)
any later version.

G-Cows 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; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */


#ifndef LIB_VARIABLES_H
#define LIB_VARIABLES_H

#include <map>
#include <vector>
#include <utility>
#include "common.H"
#include "error.H"

using std::string;
using std::vector;
using std::map;


class Gen_type;

typedef vector<Gen_type> Gen_type_vector;
typedef Gen_type_vector::iterator Gen_type_iter;
typedef Gen_type_vector::const_iterator Gen_type_c_iter;

class Gen_type {
public:
  Gen_type () : type ('u'), int_value (0),  str_value ("") {}
  Gen_type (int int_in) : type ('i'), int_value (int_in), str_value ("") {}
  Gen_type (char *char_in) : type ('c'), int_value (0), str_value (char_in) {}
  Gen_type (string str_in) : type ('c'), int_value (0), str_value (str_in) {}
  Gen_type (char c) : type (c), int_value (0), str_value ("") {} 
  // Functions releated to type identification 
  bool is_int       ()  const { return type == 'i'; }
  bool is_string    ()  const { return type == 'c'; } 
  bool is_array     ()  const { return type == 'a'; }
  bool is_list      ()  const { return type == 'l'; }
  bool is_undefined ()  const { return type == 'u'; }
  char get_type     ()  const { return type; }
  void fix_list     ();
  void push_items   (Gen_type value);
  operator bool     () const;
  Gen_type operator>(const Gen_type& right_val) const;
  Gen_type operator<(const Gen_type& right_val) const;
  Gen_type operator>=(const Gen_type& right_val) const;
  Gen_type operator<=(const Gen_type& right_val) const;
  Gen_type operator==(const Gen_type& right_val) const;
  Gen_type operator!=(const Gen_type& right_val) const;
  Gen_type operator+(const Gen_type& right_val) const;
  Gen_type operator-(const Gen_type& right_val) const;
  Gen_type operator*(const Gen_type& right_val) const;
  Gen_type operator/(const Gen_type& right_val) const;
  Gen_type operator%(const Gen_type& right_val) const;
  Gen_type operator^(const Gen_type& right_val) const;
  Gen_type operator-() const;
  Gen_type operator!() const { return Gen_type ( ! (bool)(*this)); }
  Gen_type weak_eq (const Gen_type& right_val) const;
  Gen_type weak_neq (const Gen_type& right_val) const;
  string get_string () const; 
  int    get_int    () const;
  const Gen_type_vector *get_array () const;
  const Gen_type_vector *get_list  () const;
  Gen_type get_element (Gen_type index);
  Gen_type set_element (Gen_type value);
  Gen_type set_element (Gen_type index, Gen_type value, bool shift=false);
  Gen_type insert_element (Gen_type index, Gen_type value) {
    return set_element (index, value, true); }
  bool   to_bool  ();
  int    to_int    (); 
  string to_string (bool scalar_only=false) const;
  void   push      (Gen_type item) { arr_value.push_back (item); } 
  void   erase     (unsigned int pos);
  void   erase     (unsigned int pos, unsigned int len);
private:
  char            type;
  int             int_value; 
  string          str_value;
  Gen_type_vector arr_value;
};

typedef map<string, Gen_type> Var_container;
typedef Var_container::iterator Var_iterator;

class Variables {
public:
  Variables ();
  Gen_type set_var (string name, Gen_type value);
  Gen_type set_var (string assignment);
  Gen_type get_var (string name);
  Gen_type get_array_element (string name, Gen_type index);
  Gen_type set_array_element (string name, Gen_type index, Gen_type value, 
                              bool shift=false);
  bool is_def (string name) { return (!( vars.find (name) == vars.end ()));};
  bool undef (string name);
private:
  Var_container vars;
};

#endif // ! LIB_VARIABLES_H