#ifndef SHSTR_H
#define SHSTR_H

#include <string>
#include <vector>
#include <iostream>

#include <glib.h>

#ifdef WANT_STRLEN
# define WANT_STRLEN 1
#else
# define WANT_STRLEN 0
#endif

#if WANT_STRLEN
# define SHSTRLEN(str)  strlen (str)
#else
# define SHSTRLEN(str)  0
#endif

struct shentry
{
  shentry (char const *str, const size_t hash)
  : m_refcnt (0), m_str (str), m_len (SHSTRLEN (str)), m_hash (hash)
  {
  }

  void *operator new (size_t n)
  {
    return g_slice_alloc (n);
  }

  void operator delete (void *ptr, size_t n)
  {
    g_slice_free1 (n, ptr);
  }

  size_t m_refcnt;
  char const * const m_str;
  size_t m_len;
  size_t m_hash;
};

class shstr
{
public:
  static char const *insert (char const *str, size_t *size);

  static void erase (char const *str);

  static size_t refs (char const *str);
  static size_t strcnt ();

  static size_t memused ();

protected:
  static size_t m_cnt;

  static size_t m_bucketcnt;

  typedef std::vector<shentry *> pairs;

  static pairs *m_buckets;

  static shentry *prepare (char const *str);
  static bool unref (char const *str);
  static const shentry *get (char const *str);

  static pairs::iterator find (char const *str, size_t n);

  static size_t hash (char const *str);

public:
  void *operator new (size_t n)
  {
    return g_slice_alloc (n);
  }

  void operator delete (void *ptr, size_t n)
  {
    g_slice_free1 (n, ptr);
  }

  typedef size_t size_type;

  shstr (char const *str = "");
  shstr (const shstr &rhs);
  ~shstr ();

  char const *c_str () const;
  size_type length () const;
  shstr &operator = (char const *rhs);
  shstr &operator = (const shstr &rhs);
  bool operator == (const shstr &rhs) const;
  bool operator != (const shstr &rhs) const;

  friend std::ostream &operator << (std::ostream &os, const shstr &str)
  {
    os << str.m_str;
    return os;
  }

protected:
  char const *m_str;
  size_type m_len;

  void erase ()
  {
    erase (m_str);
    m_str = NULL;
  }

  void insert (char const *newstr)
  {
    m_str = insert (newstr, &m_len);
  }
};

#endif // SHSTR_H