/* OctaveGUI - A graphical user interface for Octave
 * Copyright (C) 2011 Jacob Dawid (jacob.dawid@googlemail.com)
 *
 * This program 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.
 *
 * This program 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. If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef OCTAVEEVENT_H
#define OCTAVEEVENT_H

#include <string>
#include "octave-event-observer.h"
#include "octave/config.h"
#include "symtab.h"
#include "oct-env.h"
#include "pt-eval.h"
#include "toplev.h"
#include "parse.h"
#include "debug.h"
#include "cmd-hist.h"

#include <readline/readline.h>

/**
  * \class octave_event
  * \brief Base class for an octave event.
  * In order to make communication with octave threadsafe, comunication is
  * implemented via events. An application may create events and post them,
  * however there is no guarantee events will be processed in a given time.
  *
  * In order to create an event, there must be an event observer. The event
  * observer will be given the opportunity to react on the event as soon as
  * it has been processed in the octave thread. Accepting and ignoring takes
  * places in the octave thread.
  */
class octave_event
{
  public:
    octave_event (octave_event_observer& o)
      : _octave_event_observer (o)
    { }

    virtual ~octave_event ()
    { }

    /** Performs what is necessary to make this event happen.
      * This code is thread-safe since it will be executed in the octave thread.
      * However, you should take care to keep this code as short as possible. */
    virtual bool perform () = 0;

    /**
      * Accepts this event. This allows the event observer to react properly
      * onto the event.
      */
    void accept ()
    { _octave_event_observer.event_accepted (this); }

    /**
      * Rejects this event. This allows the event observer to react properly
      * onto the event.
      */
    void reject ()
    { _octave_event_observer.event_reject (this); }

  protected:
    void call_octave_function (std::string name,
                               const octave_value_list& args = octave_value_list (),
                               int nargout = 0)
    {
      try
      {
        feval (name, args, nargout);
      } catch (...) { } // Ignore exceptions. Crashes without that.
    }

    void finish_readline_event () const
    {
      rl_line_buffer[0] = '\0';
      rl_point = rl_end = 0;
      rl_done = 1;
      //rl_forced_update_display ();
    }

  private:
    octave_event_observer& _octave_event_observer;
};

class octave_update_history_event : public octave_event
{
  public:
    /** Creates a new octave_exit_event. */
    octave_update_history_event (octave_event_observer& o)
      : octave_event (o)
    { }

    bool perform ()
    { return true; /* Always grant. */ }
};

class octave_update_workspace_event : public octave_event
{
  public:
    /** Creates a new octave_exit_event. */
    octave_update_workspace_event (octave_event_observer& o)
      : octave_event (o)
    { }

    bool perform ()
    { return true; /* Always grant. */ }
};

/** Implements an octave exit event. */
class octave_exit_event : public octave_event
{
  public:
    /** Creates a new octave_exit_event. */
    octave_exit_event (octave_event_observer& o)
      : octave_event (o)
    { }

    bool perform ()
    { clean_up_and_exit (0); return true; }
};

/** Implements an octave run file event. */
class octave_run_file_event : public octave_event
{
  public:
    /** Creates a new octave_run_file_event. */
    octave_run_file_event (octave_event_observer& o,
                           std::string file)
      : octave_event (o)
    { _file = file; }

    bool perform ()
    {
      octave_value_list args;
      args.append (octave_value (_file));
      call_octave_function ("run", args);
      finish_readline_event ();
      return true;
    }

  private:
    std::string _file;
};

/** Implements a change directory event. */
class octave_change_directory_event : public octave_event
{
  public:
    /** Creates a new octave_change_directory_event. */
    octave_change_directory_event (octave_event_observer& o,
                                   std::string directory)
      : octave_event (o)
    { _directory = directory; }

    bool perform ()
    { return octave_env::chdir (_directory); }

  private:
    std::string _directory;
};

/** Implements a clear workspace event. */
class octave_clear_workspace_event : public octave_event
{
  public:
    /** Creates a new octave_run_file_event. */
    octave_clear_workspace_event (octave_event_observer& o)
      : octave_event (o)
    { }

    bool perform ()
    {
      call_octave_function ("clear");
      return true;
    }
};

/** Implements a load workspace event. */
class octave_load_workspace_event : public octave_event
{
  public:
    /** Creates a new octave_change_directory_event. */
    octave_load_workspace_event (octave_event_observer& o,
                                 std::string file)
      : octave_event (o)
    { _file = file; }

    bool perform ()
    {
      octave_value_list args;
      args.append (octave_value (_file));
      call_octave_function ("load", args);
      return true;
    }

  private:
    std::string _file;
};

/** Implements a save workspace event. */
class octave_save_workspace_event : public octave_event
{
  public:
    /** Creates a new octave_change_directory_event. */
    octave_save_workspace_event (octave_event_observer& o,
                                 std::string file)
      : octave_event (o)
    { _file = file; }

    bool perform ()
    {
      octave_value_list args;
      args.append (octave_value (_file));
      call_octave_function ("save", args);
      return true;
    }

  private:
    std::string _file;
};

class octave_clear_history_event : public octave_event
{
  public:
    /** Creates a new octave_clear_history_event. */
    octave_clear_history_event (octave_event_observer& o)
      : octave_event (o)
    { }

    bool perform ()
    {
      int i;
      while ((i = command_history::length ()) > 0) {
          command_history::remove (i - 1);
        }
      return true;
    }
};

class octave_add_breakpoint_event : public octave_event
{
  public:
    octave_add_breakpoint_event (octave_event_observer& o,
                                 std::string path,
                                 std::string function_name,
                                 int line)
      : octave_event (o)
    {
      _path = path;
      _function_name = function_name;
      _line = line;
    }

    bool perform ()
    {
      bp_table::intmap intmap;
      intmap[0] = _line;

      // TODO: Check success.
      std::string previous_directory = octave_env::get_current_directory ();
      octave_env::chdir (_path);
      bp_table::add_breakpoint (_function_name, intmap);
      octave_env::chdir (previous_directory);
      return true;
    }

    std::string get_path ()
    {
      return _path;
    }

    std::string get_function_name ()
    {
      return _function_name;
    }

    int get_line ()
    {
      return _line;
    }

  private:
    std::string _path;
    std::string _function_name;
    int _line;
};

class octave_remove_breakpoint_event : public octave_event
{
  public:
    octave_remove_breakpoint_event (octave_event_observer& o,
                                    std::string path,
                                    std::string function_name,
                                    int line)
      : octave_event (o)
    {
      _path = path;
      _function_name = function_name;
      _line = line;
    }

    bool perform ()
    {
      bp_table::intmap intmap;
      intmap[0] = _line;

      // TODO: Check success.
      std::string previous_directory = octave_env::get_current_directory ();
      octave_env::chdir (_path);
      bp_table::remove_breakpoint (_function_name, intmap);
      octave_env::chdir (previous_directory);
      return true;
    }

    std::string get_path ()
    {
      return _path;
    }

    std::string get_function_name ()
    {
      return _function_name;
    }

    int get_line ()
    {
      return _line;
    }

  private:
    std::string _path;
    std::string _function_name;
    int _line;
};

class octave_remove_all_breakpoints_event : public octave_event
{
  public:
    octave_remove_all_breakpoints_event (octave_event_observer& o,
                                         std::string file)
      : octave_event (o)
    {
      _file = file;
    }

    bool perform ()
    {
      // TODO: Check success.
      bp_table::remove_all_breakpoints_in_file (_file, true);
      return true;
    }

  private:
    std::string _file;
};

class octave_debug_step_into_event : public octave_event
{
  public:
    /** Creates a new octave_debug_step_into_event. */
    octave_debug_step_into_event (octave_event_observer& o)
      : octave_event (o) { }

    bool perform ()
    {
      octave_value_list args;
      args.append (octave_value ("in"));
      call_octave_function ("dbstep", args);
      finish_readline_event ();
      return true;
    }
};

class octave_debug_step_over_event : public octave_event
{
  public:
    /** Creates a new octave_debug_step_over_event. */
    octave_debug_step_over_event (octave_event_observer& o)
      : octave_event (o) { }

    bool perform ()
    {
      call_octave_function ("dbnext");
      finish_readline_event ();
      return true;
    }
};

class octave_debug_step_out_event : public octave_event
{
  public:
    /** Creates a new octave_debug_step_out_event. */
    octave_debug_step_out_event (octave_event_observer& o)
      : octave_event (o) { }

    bool perform ()
    {
      octave_value_list args;
      args.append (octave_value ("out"));
      call_octave_function ("dbstep", args);
      finish_readline_event ();
      return true;
    }
};

class octave_debug_continue_event : public octave_event
{
  public:
    /** Creates a new octave_debug_step_out_event. */
    octave_debug_continue_event (octave_event_observer& o)
      : octave_event (o) { }

    bool perform ()
    {
      call_octave_function ("dbcont");
      finish_readline_event ();
      return true;
    }
};

class octave_debug_quit_event : public octave_event
{
  public:
    /** Creates a new octave_debug_step_out_event. */
    octave_debug_quit_event (octave_event_observer& o)
      : octave_event (o) { }

    bool perform ()
    {
      call_octave_function ("dbquit");
      finish_readline_event ();
      return true;
    }
};

#endif // OCTAVEEVENT_H