/*

Copyright (C) 2012-2019 Michael Goffioul

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
<https://www.gnu.org/licenses/>.

*/

#if ! defined (octave_cdef_class_h)
#define octave_cdef_class_h 1

#include "octave-config.h"

#include <map>
#include <set>
#include <string>

#include "oct-refcount.h"

#include "cdef-method.h"
#include "cdef-object.h"
#include "cdef-package.h"
#include "cdef-property.h"
#include "ov.h"
#include "ovl.h"

namespace octave
{
  class interpreter;
  class tree_classdef;
}

class
cdef_class : public cdef_meta_object
{
private:

  class
  cdef_class_rep : public cdef_meta_object_rep
  {
  public:
    cdef_class_rep (void)
      : cdef_meta_object_rep (), member_count (0), handle_class (false),
        object_count (0), meta (false)
    { }

    cdef_class_rep (const std::list<cdef_class>& superclasses);

    cdef_class_rep& operator = (const cdef_class_rep&) = delete;

    ~cdef_class_rep (void) = default;

    cdef_object_rep * copy (void) const { return new cdef_class_rep (*this); }

    bool is_class (void) const { return true; }

    std::string get_name (void) const
    { return get ("Name").string_value (); }

    void set_name (const std::string& nm) { put ("Name", nm); }

    bool is_abstract (void) const { return get ("Abstract").bool_value (); }

    bool is_sealed (void) const { return get ("Sealed").bool_value (); }

    cdef_method find_method (const std::string& nm, bool local = false);

    void install_method (const cdef_method& meth);

    Cell get_methods (void);

    std::map<std::string, cdef_method> get_method_map (bool only_inherited);

    cdef_property find_property (const std::string& nm);

    void install_property (const cdef_property& prop);

    Cell get_properties (int mode);

    std::map<std::string, cdef_property> get_property_map (int mode);

    string_vector get_names (void);

    void set_directory (const std::string& dir) { directory = dir; }

    std::string get_directory (void) const { return directory; }

    void delete_object (const cdef_object& obj);

    octave_value_list
    meta_subsref (const std::string& type,
                  const std::list<octave_value_list>& idx, int nargout);

    void meta_release (void);

    bool meta_accepts_postfix_index (char type) const
    {
      return (type == '(' || type == '.');
    }

    octave_value construct (const octave_value_list& args);

    cdef_object construct_object (const octave_value_list& args);

    void initialize_object (cdef_object& obj);

    void run_constructor (cdef_object& obj, const octave_value_list& args);

    void mark_as_handle_class (void) { handle_class = true; }

    bool is_handle_class (void) const { return handle_class; }

    void register_object (void) { object_count++; }

    void unregister_object (void) { object_count--; }

    octave_idx_type static_count (void) const { return member_count; }

    void destroy (void)
    {
      if (member_count)
        {
          refcount++;
          cdef_class lock (this);

          member_count = 0;
          method_map.clear ();
          property_map.clear ();
        }
      else
        delete this;
    }

    void mark_as_meta_class (void) { meta = true; }

    bool is_meta_class (void) const { return meta; }

  private:

    void load_all_methods (void);

    void find_names (std::set<std::string>& names, bool all);

    void find_properties (std::map<std::string,cdef_property>& props,
                          int mode = 0);

    void find_methods (std::map<std::string, cdef_method>& meths,
                       bool only_inherited);

    cdef_class wrap (void)
    {
      refcount++;
      return cdef_class (this);
    }

    // The @-directory were this class is loaded from.
    // (not used yet)

    std::string directory;

    // The methods defined by this class.

    std::map<std::string,cdef_method> method_map;

    // The properties defined by this class.

    std::map<std::string,cdef_property> property_map;

    // The number of members in this class (methods, properties...)

    octave_idx_type member_count;

    // TRUE if this class is a handle class.  A class is a handle
    // class when the abstract "handle" class is one of its superclasses.

    bool handle_class;

    // The list of super-class constructors that are called implicitly by the
    // the classdef engine when creating an object.  These constructors are not
    // called explicitly by the class constructor.

    std::list<cdef_class> implicit_ctor_list;

    // The number of objects of this class.

    octave::refcount<octave_idx_type> object_count;

    // TRUE if this class is a built-in meta class.

    bool meta;

    // Utility iterator typedefs.

    typedef std::map<std::string,cdef_method>::iterator method_iterator;
    typedef std::map<std::string,cdef_method>::const_iterator method_const_iterator;
    typedef std::map<std::string,cdef_property>::iterator property_iterator;
    typedef std::map<std::string,cdef_property>::const_iterator property_const_iterator;

    cdef_class_rep (const cdef_class_rep& c)
      : cdef_meta_object_rep (c), directory (c.directory),
        method_map (c.method_map), property_map (c.property_map),
        member_count (c.member_count), handle_class (c.handle_class),
        implicit_ctor_list (c.implicit_ctor_list),
        object_count (c.object_count), meta (c.meta) { }
  };

public:

  // Create an invalid class object.

  cdef_class (void) : cdef_meta_object () { }

  cdef_class (const std::string& nm, const std::list<cdef_class>& superclasses)
    : cdef_meta_object (new cdef_class_rep (superclasses))
  {
    get_rep ()->set_name (nm);
  }

  cdef_class (const cdef_class& cls) : cdef_meta_object (cls) { }

  cdef_class (const cdef_object& obj)
    : cdef_meta_object (obj)
  {
    // This should never happen...
    if (! is_class ())
      error ("internal error: invalid assignment from %s to meta.class object",
             class_name ().c_str ());
  }

  cdef_class& operator = (const cdef_class& cls)
  {
    cdef_object::operator = (cls);

    return *this;
  }

  ~cdef_class (void) = default;

  cdef_method find_method (const std::string& nm, bool local = false);

  void install_method (const cdef_method& meth)
  {
    get_rep ()->install_method (meth);
  }

  Cell get_methods (void) { return get_rep ()->get_methods (); }

  std::map<std::string, cdef_method>
  get_method_map (bool only_inherited = false)
  {
    return get_rep ()->get_method_map (only_inherited);
  }

  cdef_property find_property (const std::string& nm);

  void install_property (const cdef_property& prop)
  {
    get_rep ()->install_property (prop);
  }

  Cell get_properties (int mode = property_normal)
  {
    return get_rep ()->get_properties (mode);
  }

  std::map<std::string, cdef_property>
  get_property_map (int mode = property_normal)
  {
    return get_rep ()->get_property_map (mode);
  }

  string_vector get_names (void) { return get_rep ()->get_names (); }

  bool is_abstract (void) const { return get_rep ()->is_abstract (); }

  bool is_sealed (void) const { return get_rep ()->is_sealed (); }

  void set_directory (const std::string& dir)
  {
    get_rep ()->set_directory (dir);
  }

  std::string get_directory (void) const
  {
    return get_rep ()->get_directory ();
  }

  std::string get_name (void) const { return get_rep ()->get_name (); }

  bool is_builtin (void) const { return get_directory ().empty (); }

  void delete_object (const cdef_object& obj)
  {
    get_rep ()->delete_object (obj);
  }

  //! Analyze the tree_classdef tree and transform it to a cdef_class
  //!
  //! <b>All attribute validation should occur here.</b>
  //!
  //! Classdef attribute values can be given in the form of
  //! expressions.  These expressions must be evaluated before
  //! assigning them as attribute values.  Evaluating them as they are
  //! parsed causes trouble with possible recusion in the parser so we
  //! do it here.  For example
  //!
  //! @code
  //! classdef recursion_class
  //!   methods (Access = ?recursion_class)
  //!   endmethods
  //! endclassdef
  //! @endcode
  //!
  //! will fail because each attempt to compute the metaclass of
  //! recursion_class will cause recursion_class to be parsed again.

  static cdef_class
  make_meta_class (octave::interpreter& interp, octave::tree_classdef *t,
                   bool is_at_folder = false);

  octave_function * get_method_function (const std::string& nm);

  octave_function * get_constructor_function (void)
  {
    return get_method_function (get_name ());
  }

  octave_value construct (const octave_value_list& args)
  {
    return get_rep ()->construct (args);
  }

  cdef_object construct_object (const octave_value_list& args)
  {
    return get_rep ()->construct_object (args);
  }

  void initialize_object (cdef_object& obj)
  {
    get_rep ()->initialize_object (obj);
  }

  void run_constructor (cdef_object& obj, const octave_value_list& args)
  {
    get_rep ()->run_constructor (obj, args);
  }

  void mark_as_handle_class (void)
  {
    get_rep ()->mark_as_handle_class ();
  }

  bool is_handle_class (void) const
  {
    return get_rep ()->is_handle_class ();
  }

  void mark_as_meta_class (void) { get_rep ()->mark_as_meta_class (); }

  bool is_meta_class (void) const { return get_rep ()->is_meta_class (); }

  void register_object (void) { get_rep ()->register_object (); }

  void unregister_object (void) { get_rep ()->unregister_object (); }

public:

  enum
  {
    property_normal,
    property_inherited,
    property_all
  };

private:

  cdef_class_rep * get_rep (void)
  {
    return dynamic_cast<cdef_class_rep *> (cdef_object::get_rep ());
  }

  const cdef_class_rep * get_rep (void) const
  {
    return dynamic_cast<const cdef_class_rep *> (cdef_object::get_rep ());
  }

  friend bool operator == (const cdef_class&, const cdef_class&);
  friend bool operator != (const cdef_class&, const cdef_class&);
  friend bool operator < (const cdef_class&, const cdef_class&);

  friend void install_classdef (octave::interpreter& interp);
};

inline bool
operator == (const cdef_class& clsa, const cdef_class& clsb)
{
  // FIXME: is this really the right way to check class equality?

  return (clsa.get_rep () == clsb.get_rep ());
}

inline bool
operator != (const cdef_class& clsa, const cdef_class& clsb)
{
  return ! (clsa == clsb);
}

// This is only to be able to use cdef_class as map keys.

inline bool
operator < (const cdef_class& clsa, const cdef_class& clsb)
{
  return clsa.get_rep () < clsb.get_rep ();
}

inline cdef_method
cdef_class::find_method (const std::string& nm, bool local)
{
  return get_rep ()->find_method (nm, local);
}

inline cdef_property
cdef_class::find_property (const std::string& nm)
{
  return get_rep ()->find_property (nm);
}

#endif