/*

Copyright (C) 1994, 1995, 1996, 1997, 2000, 2002, 2003, 2004, 2005,
              2006, 2007, 2009 John W. Eaton
Copyright (C) 2010 VZLU Prague

This file is part of Octave.

Octave 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 3 of the License, or (at your
option) any later version.

Octave 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 Octave; see the file COPYING.  If not, see
<http://www.gnu.org/licenses/>.

*/

#if !defined (octave_oct_map_h)
#define octave_oct_map_h 1

#include <algorithm>
#include <map>

#include "Cell.h"
#include "oct-obj.h"

class string_vector;

// A class holding a map field->index. Supports reference-counting.
class OCTINTERP_API 
octave_fields
{
  class fields_rep : public std::map<std::string, octave_idx_type>
  {
  public:
    fields_rep (void) : std::map<std::string, octave_idx_type> (), count (1) { }
    fields_rep (const fields_rep& other)
      : std::map<std::string, octave_idx_type> (other), count (1) { }

    int count;

  private:
    fields_rep& operator = (const fields_rep&); // no assignment!
  };

  fields_rep *rep;

  static fields_rep *nil_rep (void)
    {
      static fields_rep *nr = new fields_rep ();
      return nr;
    }

public:

  octave_fields (void) : rep (nil_rep ()) { rep->count++; }
  octave_fields (const string_vector&);
  octave_fields (const char * const *);

  ~octave_fields (void)
    {
      if (--rep->count == 0)
        delete rep;
    }

  void make_unique (void)
    {
      if (rep->count > 1)
        {
          --rep->count;
          rep = new fields_rep (*rep);
        }
    }

  octave_fields (const octave_fields& o) : rep (o.rep) { rep->count++; }

  octave_fields& 
  operator = (const octave_fields& o)
    {
      o.rep->count++;
      if (--rep->count == 0)
        delete rep;
      rep = o.rep;

      return *this;
    }

  // constant iteration support. non-const iteration intentionally unsupported.

  typedef std::map<std::string, octave_idx_type>::const_iterator const_iterator;
  typedef const_iterator iterator;

  const_iterator begin (void) const { return rep->begin (); }
  const_iterator end (void) const { return rep->end (); }

  std::string key (const_iterator p) const { return p->first; }
  octave_idx_type index (const_iterator p) const { return p->second; }

  const_iterator seek (const std::string& k) const 
    { return rep->find (k); }

  // high-level methods.

  // number of fields.
  octave_idx_type nfields (void) const { return rep->size (); }

  // check whether a field exists.
  bool isfield (const std::string& name) const;

  // get index of field. return -1 if not exist
  octave_idx_type getfield (const std::string& name) const;
  // get index of field. add if not exist
  octave_idx_type getfield (const std::string& name);
  // remove field and return the index. -1 if didn't exist.
  octave_idx_type rmfield (const std::string& name);

  // order the fields of this map. creates a permutation
  // used to order the fields.
  void orderfields (Array<octave_idx_type>& perm);

  // compares two instances for equality up to order of fields.
  // returns a permutation needed to bring the fields of *other*
  // into the order of *this*.
  bool equal_up_to_order (const octave_fields& other,
                          octave_idx_type* perm) const;

  bool equal_up_to_order (const octave_fields& other,
                          Array<octave_idx_type>& perm) const;

  bool is_same (const octave_fields& other) const
    { return rep == other.rep; }

  // Returns the fields as a vector of strings.
  string_vector fieldnames (void) const;

  void clear (void)
    {
      *this = octave_fields ();
    }
};


class OCTINTERP_API
octave_scalar_map
{
public:

  octave_scalar_map (const octave_fields& k)
    : xkeys (k), xvals (k.nfields ()) { }

  octave_scalar_map (void) : xkeys (), xvals () { }

  octave_scalar_map (const string_vector& k)
    : xkeys (k), xvals (k.length ()) { }

  octave_scalar_map (const octave_scalar_map& m)
    : xkeys (m.xkeys), xvals(m.xvals) { }

  octave_scalar_map& operator = (const octave_scalar_map& m)
    {
      xkeys = m.xkeys;
      xvals = m.xvals;

      return *this;
    }

  // iteration support. note that both const and non-const iterators are the
  // same. The const/non-const distinction is made by the key & contents method.
  typedef octave_fields::const_iterator const_iterator;
  typedef const_iterator iterator;

  const_iterator begin (void) const { return xkeys.begin (); }
  const_iterator end (void) const { return xkeys.end (); }

  const_iterator seek (const std::string& k) const { return xkeys.seek (k); }

  std::string key (const_iterator p) const 
    { return xkeys.key (p); }
  octave_idx_type index (const_iterator p) const
    { return xkeys.index (p); }

  const octave_value& contents (const_iterator p) const 
    { return xvals[xkeys.index (p)]; }

  octave_value& contents (iterator p)
    { return xvals[xkeys.index (p)]; }

  const octave_value& contents (octave_idx_type i) const
    { return xvals[i]; }

  octave_value& contents (octave_idx_type i)
    { return xvals[i]; }

  // number of fields.
  octave_idx_type nfields (void) const { return xkeys.nfields (); }

  // check whether a field exists.
  bool isfield (const std::string& name) const 
    { return xkeys.isfield (name); }

  bool contains (const std::string& name) const 
    { return isfield (name); }

  string_vector fieldnames (void) const
    { return xkeys.fieldnames (); }

  string_vector keys (void) const
    { return fieldnames (); }

  // get contents of a given field. empty value if not exist.
  octave_value getfield (const std::string& key) const;

  // set contents of a given field. add if not exist.
  void setfield (const std::string& key, const octave_value& val);
  void assign (const std::string& k, const octave_value& val)
    { setfield (k, val); }

  // remove a given field. do nothing if not exist.
  void rmfield (const std::string& key);
  void del (const std::string& k) { rmfield (k); }

  // return a copy with fields ordered, optionally along with permutation.
  octave_scalar_map orderfields (void) const;
  octave_scalar_map orderfields (Array<octave_idx_type>& perm) const;
  octave_scalar_map orderfields (const octave_scalar_map& other,
                                 Array<octave_idx_type>& perm) const;

  // aka getfield/setfield, but the latter returns a reference.
  octave_value contents (const std::string& k) const;
  octave_value& contents (const std::string& k);

  void clear (void)
    {
      xkeys.clear ();
      xvals.clear ();
    }

  friend class octave_map;

private:

  octave_fields xkeys;
  std::vector<octave_value> xvals;

};

template<>
inline octave_scalar_map octave_value_extract<octave_scalar_map> (const octave_value& v)
  { return v.scalar_map_value (); }

class OCTINTERP_API
octave_map
{
public:

  octave_map (const octave_fields& k)
    : xkeys (k), xvals (k.nfields ()), dimensions () { }

  octave_map (const dim_vector& dv, const octave_fields& k)
    : xkeys (k), xvals (k.nfields (), Cell (dv)), dimensions (dv) { }

  typedef octave_scalar_map element_type;

  octave_map (void) : xkeys (), xvals (), dimensions () { }

  octave_map (const dim_vector& dv) : xkeys (), xvals (), dimensions (dv) { }

  octave_map (const string_vector& k)
    : xkeys (k), xvals (k.length ()), dimensions (1, 1) { }

  octave_map (const dim_vector& dv, const string_vector& k)
    : xkeys (k), xvals (k.length (), Cell (dv)), dimensions (dv) { }

  octave_map (const octave_map& m)
    : xkeys (m.xkeys), xvals (m.xvals), dimensions (m.dimensions) { }

  octave_map (const octave_scalar_map& m);

  octave_map (const Octave_map& m);

  octave_map& operator = (const octave_map& m)
    {
      xkeys = m.xkeys;
      xvals = m.xvals;
      dimensions = m.dimensions;

      return *this;
    }

  // iteration support. note that both const and non-const iterators are the
  // same. The const/non-const distinction is made by the key & contents method.
  typedef octave_fields::const_iterator const_iterator;
  typedef const_iterator iterator;

  const_iterator begin (void) const { return xkeys.begin (); }
  const_iterator end (void) const { return xkeys.end (); }

  const_iterator seek (const std::string& k) const { return xkeys.seek (k); }

  std::string key (const_iterator p) const 
    { return xkeys.key (p); }
  octave_idx_type index (const_iterator p) const
    { return xkeys.index (p); }

  const Cell& contents (const_iterator p) const 
    { return xvals[xkeys.index (p)]; }

  Cell& contents (iterator p)
    { return xvals[xkeys.index (p)]; }

  const Cell& contents (octave_idx_type i) const
    { return xvals[i]; }

  Cell& contents (octave_idx_type i)
    { return xvals[i]; }

  // number of fields.
  octave_idx_type nfields (void) const { return xkeys.nfields (); }

  // check whether a field exists.
  bool isfield (const std::string& name) const 
    { return xkeys.isfield (name); }

  bool contains (const std::string& name) const 
    { return isfield (name); }

  string_vector fieldnames (void) const
    { return xkeys.fieldnames (); }

  string_vector keys (void) const
    { return fieldnames (); }

  // get contents of a given field. empty value if not exist.
  Cell getfield (const std::string& key) const;

  // set contents of a given field. add if not exist. checks for
  // correct dimensions.
  void setfield (const std::string& key, const Cell& val);
  void assign (const std::string& k, const Cell& val)
    { setfield (k, val); } 

  // remove a given field. do nothing if not exist.
  void rmfield (const std::string& key);
  void del (const std::string& k) { rmfield (k); }

  // return a copy with fields ordered, optionally along with permutation.
  octave_map orderfields (void) const;
  octave_map orderfields (Array<octave_idx_type>& perm) const;
  octave_map orderfields (const octave_map& other,
                          Array<octave_idx_type>& perm) const;

  // aka getfield/setfield, but the latter returns a reference.
  Cell contents (const std::string& k) const;
  Cell& contents (const std::string& k);

  void clear (void)
    {
      xkeys.clear ();
      xvals.clear ();
    }

  // The Array-like methods.
  octave_idx_type numel (void) const { return dimensions.numel (); }
  octave_idx_type length (void) const { return numel (); }
  bool is_empty (void) const { return dimensions.any_zero (); }

  octave_idx_type rows (void) const { return dimensions(0); }
  octave_idx_type cols (void) const { return dimensions(1); }
  octave_idx_type columns (void) const { return dimensions(1); }

  // Extract a scalar substructure.
  octave_scalar_map checkelem (octave_idx_type n) const;
  octave_scalar_map checkelem (octave_idx_type i, octave_idx_type j) const;

  octave_scalar_map
  checkelem (const Array<octave_idx_type>& ra_idx) const;

  octave_scalar_map operator () (octave_idx_type n) const
    { return checkelem (n); }
  octave_scalar_map operator () (octave_idx_type i, octave_idx_type j) const
    { return checkelem (i, j); }

  octave_scalar_map
  operator () (const Array<octave_idx_type>& ra_idx) const
    { return checkelem (ra_idx); }

  octave_map squeeze (void) const; 

  octave_map permute (const Array<int>& vec, bool inv = false) const; 

  dim_vector dims (void) const { return dimensions; }

  int ndims (void) const { return dimensions.length (); }

  octave_map transpose (void) const;

  octave_map reshape (const dim_vector& dv) const;

  void resize (const dim_vector& dv, bool fill = false);

  static octave_map
  cat (int dim, octave_idx_type n, const octave_scalar_map *map_list);

  static octave_map
  cat (int dim, octave_idx_type n, const octave_map *map_list);

  octave_map index (const idx_vector& i, bool resize_ok = false) const;

  octave_map index (const idx_vector& i, const idx_vector& j,
                    bool resize_ok = false) const;

  octave_map index (const Array<idx_vector>& ia,
                    bool resize_ok = false) const;

  octave_map index (const octave_value_list&, bool resize_ok = false) const;
  
  octave_map column (octave_idx_type k) const;
  octave_map page (octave_idx_type k) const;

  void assign (const idx_vector& i, const octave_map& rhs);

  void assign (const idx_vector& i, const idx_vector& j, const octave_map& rhs);

  void assign (const Array<idx_vector>& ia, const octave_map& rhs);

  void assign (const octave_value_list&, const octave_map& rhs);
  
  void assign (const octave_value_list& idx, const std::string& k,
               const Cell& rhs);

  void delete_elements (const idx_vector& i);

  void delete_elements (int dim, const idx_vector& i);

  void delete_elements (const Array<idx_vector>& ia);

  void delete_elements (const octave_value_list&);

  octave_map concat (const octave_map& rb, const Array<octave_idx_type>& ra_idx);

  // like checkelem, but no check.
  octave_scalar_map fast_elem_extract (octave_idx_type n) const;

  // element assignment, no bounds check
  bool fast_elem_insert (octave_idx_type n, const octave_scalar_map& rhs);

private:

  octave_fields xkeys;
  std::vector<Cell> xvals;
  dim_vector dimensions;

  void optimize_dimensions (void);
  void extract_scalar (octave_scalar_map& dest, 
                       octave_idx_type index) const;
  static void do_cat (int dim, octave_idx_type n, 
                      const octave_scalar_map *map_list, octave_map& retval);
  static void do_cat (int dim, octave_idx_type n, 
                      const octave_map *map_list, octave_map& retval);
};

template<>
inline octave_map octave_value_extract<octave_map> (const octave_value& v)
  { return v.map_value (); }

// The original Octave_map object. Octave_map and octave_map are convertible to
// each other.

class
OCTINTERP_API
Octave_map
{
 public:

  typedef std::map<std::string, Cell>::iterator iterator;
  typedef std::map<std::string, Cell>::const_iterator const_iterator;

  typedef std::list<std::string>::iterator key_list_iterator;
  typedef std::list<std::string>::const_iterator const_key_list_iterator;

  // Warning!  You should always use at least two dimensions.

  Octave_map (const dim_vector& dv = dim_vector (0, 0),
              const Cell& key_vals = Cell ());

  Octave_map (const std::string& k, const octave_value& value)
    : map (), key_list (), dimensions (1, 1)
  {
    map[k] = value;
    key_list.push_back (k);
  }

  Octave_map (const string_vector& sv,
              const dim_vector& dv = dim_vector (0, 0))
    : map (), key_list (), dimensions (dv)
  {
    for (octave_idx_type i = 0; i < sv.length (); i++)
      {
        std::string k = sv[i];
        map[k] = Cell (dv);
        key_list.push_back (k);
      }
  }

  Octave_map (const std::string& k, const Cell& vals)
    : map (), key_list (), dimensions (vals.dims ())
  {
    map[k] = vals;
    key_list.push_back (k);
  }

  Octave_map (const std::string& k, const octave_value_list& val_list)
    : map (), key_list (), dimensions (1, val_list.length ())
  {
    map[k] = val_list;
    key_list.push_back (k);
  }

  Octave_map (const Octave_map& m)
    : map (m.map), key_list (m.key_list), dimensions (m.dimensions) { }

  Octave_map (const octave_map& m);

  Octave_map& operator = (const Octave_map& m)
    {
      if (this != &m)
        {
          map = m.map;
          key_list = m.key_list;
          dimensions = m.dimensions;
        }

      return *this;
    }

  ~Octave_map (void) { }

  Octave_map squeeze (void) const; 

  Octave_map permute (const Array<int>& vec, bool inv = false) const; 

  // This is the number of keys.
  octave_idx_type nfields (void) const { return map.size (); }

  void del (const std::string& k)
    {
      iterator p = map.find (k);

      if (p != map.end ())
        {
          map.erase (p);

          key_list_iterator q
            = std::find (key_list.begin (), key_list.end (), k);

          assert (q != key_list.end ());

          key_list.erase (q);
        }
    }

  iterator begin (void) { return iterator (map.begin ()); }
  const_iterator begin (void) const { return const_iterator (map.begin ()); }

  iterator end (void) { return iterator (map.end ()); }
  const_iterator end (void) const { return const_iterator (map.end ()); }

  std::string key (const_iterator p) const { return p->first; }

  Cell& contents (const std::string& k);
  Cell contents (const std::string& k) const;

  Cell& contents (iterator p)
    { return p->second; }

  Cell contents (const_iterator p) const
    { return p->second; }

  int intfield (const std::string& k, int def_val = 0) const;

  std::string stringfield (const std::string& k,
                           const std::string& def_val = std::string ()) const;

  iterator seek (const std::string& k) { return map.find (k); }
  const_iterator seek (const std::string& k) const { return map.find (k); }

  bool contains (const std::string& k) const
    { return (seek (k) != map.end ()); }

  void clear (void)
    {
      map.clear ();
      key_list.clear ();
    }

  string_vector keys (void) const;

  octave_idx_type rows (void) const { return dimensions(0); }

  octave_idx_type columns (void) const { return dimensions(1); }

  dim_vector dims (void) const { return dimensions; }

  int ndims (void) const { return dimensions.length (); }

  Octave_map transpose (void) const;

  Octave_map reshape (const dim_vector& new_dims) const;

  void resize (const dim_vector& dv, bool fill = false);

  octave_idx_type numel (void) const { return dimensions.numel (); }

  Octave_map concat (const Octave_map& rb, const Array<octave_idx_type>& ra_idx);

  Octave_map& maybe_delete_elements (const octave_value_list& idx);

  Octave_map& assign (const octave_value_list& idx, const Octave_map& rhs);

  Octave_map& assign (const octave_value_list& idx, const std::string& k,
                      const Cell& rhs);

  Octave_map& assign (const std::string& k, const octave_value& rhs);

  Octave_map& assign (const std::string& k, const Cell& rhs);

  Octave_map index (const octave_value_list& idx, 
                    bool resize_ok = false) const;

private:

  // The map of names to values.
  std::map<std::string, Cell> map;

  // An extra list of keys, so we can keep track of the order the keys
  // are added for compatibility with you know what.
  std::list<std::string> key_list;

  // The current size.
  mutable dim_vector dimensions;

  void maybe_add_to_key_list (const std::string& k)
    {
      if (! contains (k))
        key_list.push_back (k);
    }
};

#endif