/*

Copyright (C) 2013-2016 Torsten

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/>.

*/

// Author: Torsten <ttl@justmail.de>

#if defined (HAVE_CONFIG_H)
#  include "config.h"
#endif

#if defined (HAVE_QSCINTILLA)

#include <Qsci/qscilexer.h>
#include <Qsci/qscicommandset.h>
#include <QShortcut>
#include <QMessageBox>

#include "octave-qscintilla.h"
#include "file-editor-tab.h"
#include "shortcut-manager.h"

octave_qscintilla::octave_qscintilla (QWidget *p)
  : QsciScintilla (p)
{
  connect (this, SIGNAL (textChanged ()), this, SLOT (text_changed ()));

  // clear scintilla edit shortcuts that are handled by the editor
  QsciCommandSet *cmd_set = standardCommands ();

#if defined (HAVE_QSCI_VERSION_2_6_0)
  // find () was added in QScintilla 2.6
  cmd_set->find (QsciCommand::SelectionCopy)->setKey (0);
  cmd_set->find (QsciCommand::SelectionCut)->setKey (0);
  cmd_set->find (QsciCommand::Paste)->setKey (0);
  cmd_set->find (QsciCommand::SelectAll)->setKey (0);
  cmd_set->find (QsciCommand::SelectionDuplicate)->setKey (0);
  cmd_set->find (QsciCommand::LineTranspose)->setKey (0);
  cmd_set->find (QsciCommand::Undo)->setKey (0);
  cmd_set->find (QsciCommand::Redo)->setKey (0);
  cmd_set->find (QsciCommand::SelectionUpperCase)->setKey (0);
  cmd_set->find (QsciCommand::SelectionLowerCase)->setKey (0);
  cmd_set->find (QsciCommand::ZoomIn)->setKey (0);
  cmd_set->find (QsciCommand::ZoomOut)->setKey (0);
  cmd_set->find (QsciCommand::DeleteWordLeft)->setKey (0);
  cmd_set->find (QsciCommand::DeleteWordRight)->setKey (0);
  cmd_set->find (QsciCommand::DeleteLineLeft)->setKey (0);
  cmd_set->find (QsciCommand::DeleteLineRight)->setKey (0);
  cmd_set->find (QsciCommand::LineDelete)->setKey (0);
  cmd_set->find (QsciCommand::LineCut)->setKey (0);
  cmd_set->find (QsciCommand::LineCopy)->setKey (0);
#else
  // find commands via its default key (tricky way without find ())
  QList< QsciCommand * > cmd_list = cmd_set->commands ();
  for (int i = 0; i < cmd_list.length (); i++)
    {
      int cmd_key = cmd_list.at (i)->key ();
      switch (cmd_key)
        {
        case Qt::Key_C | Qt::CTRL :               // SelectionCopy
        case Qt::Key_X | Qt::CTRL :               // SelectionCut
        case Qt::Key_V | Qt::CTRL :               // Paste
        case Qt::Key_A | Qt::CTRL :               // SelectAll
        case Qt::Key_D | Qt::CTRL :               // SelectionDuplicate
        case Qt::Key_T | Qt::CTRL :               // LineTranspose
        case Qt::Key_Z | Qt::CTRL :               // Undo
        case Qt::Key_Y | Qt::CTRL :               // Redo
        case Qt::Key_Z | Qt::CTRL | Qt::SHIFT :   // Redo
        case Qt::Key_U | Qt::CTRL :               // SelectionLowerCase
        case Qt::Key_U | Qt::CTRL | Qt::SHIFT :   // SelectionUpperCase
        case Qt::Key_Plus | Qt::CTRL :            // ZoomIn
        case Qt::Key_Minus | Qt::CTRL :           // ZoomOut
        case Qt::Key_Backspace | Qt::CTRL | Qt::SHIFT :   // DeleteLineLeft
        case Qt::Key_Delete | Qt::CTRL | Qt::SHIFT :      // DeleteLineRight
        case Qt::Key_K | Qt::META :                       // DeleteLineRight
        case Qt::Key_Backspace | Qt::CTRL :       // DeleteWordLeft
        case Qt::Key_Delete | Qt::CTRL :          // DeleteWordRight
        case Qt::Key_L | Qt::CTRL | Qt::SHIFT :   // LineDelete
        case Qt::Key_L | Qt::CTRL :               // LineCut
        case Qt::Key_T | Qt::CTRL | Qt::SHIFT :   // LineCopy
          cmd_list.at (i)->setKey (0);
        }
    }
#endif

#if defined (Q_OS_MAC)
  // Octave interprets Cmd key as Meta whereas Qscintilla interprets it
  // as Ctrl. We thus invert Meta/Ctrl in Qscintilla's shortcuts list.
  QList< QsciCommand * > cmd_list_mac = cmd_set->commands ();
  for (int i = 0; i < cmd_list_mac.length (); i++)
    {
      // Primary key
      int key = cmd_list_mac.at (i)->key ();

      if (static_cast<int> (key | Qt::META) == key &&
          static_cast<int> (key | Qt::CTRL) != key)
        key = (key ^ Qt::META) | Qt::CTRL;
      else if (static_cast<int> (key | Qt::CTRL) == key)
        key = (key ^ Qt::CTRL) | Qt::META;

      cmd_list_mac.at (i)->setKey (key);

      // Alternate key
      key = cmd_list_mac.at (i)->alternateKey ();

      if (static_cast<int> (key | Qt::META) == key &&
          static_cast<int> (key | Qt::CTRL) != key)
        key = (key ^ Qt::META) | Qt::CTRL;
      else if (static_cast<int> (key | Qt::CTRL) == key)
        key = (key ^ Qt::CTRL) | Qt::META;

      cmd_list_mac.at (i)->setAlternateKey (key);
    }
#endif

  // init state of undo/redo action for this tab
  emit status_update (isUndoAvailable (), isRedoAvailable ());
}

octave_qscintilla::~octave_qscintilla ()
{ }

void
octave_qscintilla::get_global_textcursor_pos (QPoint *global_pos,
                                              QPoint *local_pos)
{
  long position = SendScintilla (SCI_GETCURRENTPOS);
  long point_x  = SendScintilla
                    (SCI_POINTXFROMPOSITION,0,position);
  long point_y  = SendScintilla
                    (SCI_POINTYFROMPOSITION,0,position);
  *local_pos = QPoint (point_x,point_y);  // local cursor position
  *global_pos = mapToGlobal (*local_pos); // global position of cursor
}

// determine the actual word and whether we are in an octave or matlab script
bool
octave_qscintilla::get_actual_word ()
{
  QPoint global_pos, local_pos;
  get_global_textcursor_pos (&global_pos, &local_pos);
  _word_at_cursor = wordAtPoint (local_pos);
  QString lexer_name = lexer ()->lexer ();
  return ((lexer_name == "octave" || lexer_name == "matlab")
          && ! _word_at_cursor.isEmpty ());
}

// call documentation or help on the current word
void
octave_qscintilla::context_help_doc (bool documentation)
{
  if (get_actual_word ())
    contextmenu_help_doc (documentation);
}

// call edit the function related to the current word
void
octave_qscintilla::context_edit ()
{
  if (get_actual_word ())
    contextmenu_edit (true);
}

// call edit the function related to the current word
void
octave_qscintilla::context_run ()
{
  if (hasSelectedText ())
    contextmenu_run (true);
}

// context menu requested
void
octave_qscintilla::contextMenuEvent (QContextMenuEvent *e)
{
#if defined (HAVE_QSCI_VERSION_2_6_0)
  QPoint global_pos, local_pos;                         // the menu's position
  QMenu *context_menu = createStandardContextMenu ();  // standard menu

  bool in_left_margin = false;

  // determine position depending on mouse or keyboard event
  if (e->reason () == QContextMenuEvent::Mouse)
    {
      // context menu by mouse
      global_pos = e->globalPos ();            // global mouse position
      local_pos  = e->pos ();                  // local mouse position
      if (e->x () < marginWidth (1) + marginWidth (2))
        in_left_margin = true;
    }
  else
    {
      // context menu by keyboard or other: get point of text cursor
      get_global_textcursor_pos (&global_pos, &local_pos);
      QRect editor_rect = geometry ();      // editor rect mapped to global
      editor_rect.moveTopLeft
      (parentWidget ()->mapToGlobal (editor_rect.topLeft ()));
      if (! editor_rect.contains (global_pos))  // is cursor outside editor?
        global_pos = editor_rect.topLeft ();   // yes, take top left corner
    }

#if defined (HAVE_QSCI_VERSION_2_6_0)
  if (! in_left_margin)
#endif
    {
      // fill context menu with editor's standard actions
      emit create_context_menu_signal (context_menu);

      // additional custom entries of the context menu
      context_menu->addSeparator ();   // separator before custom entries

      // help menu: get the position of the mouse or the text cursor
      // (only for octave files)
      QString lexer_name = lexer ()->lexer ();
      if (lexer_name == "octave" || lexer_name == "matlab")
        {
          _word_at_cursor = wordAtPoint (local_pos);
          if (! _word_at_cursor.isEmpty ())
            {
              context_menu->addAction (tr ("Help on") + " " + _word_at_cursor,
                                       this, SLOT (contextmenu_help (bool)));
              context_menu->addAction (tr ("Documentation on")
                                       + " " + _word_at_cursor,
                                       this, SLOT (contextmenu_doc (bool)));
              context_menu->addAction (tr ("Edit") + " " + _word_at_cursor,
                                       this, SLOT (contextmenu_edit (bool)));
            }
        }
    }
#if defined (HAVE_QSCI_VERSION_2_6_0)
  else
    {
      // remove all standard actions from scintilla
      QList<QAction *> all_actions = context_menu->actions ();
      QAction* a;

      foreach (a, all_actions)
      context_menu->removeAction (a);

      a = context_menu->addAction (tr ("dbstop if ..."), this,
                                   SLOT (contextmenu_break_condition (bool)));
      a->setData (local_pos);
    }
#endif

  // finaly show the menu
  context_menu->exec (global_pos);
#endif
}

// handle the menu entry for calling help or doc
void
octave_qscintilla::contextmenu_doc (bool)
{
  contextmenu_help_doc (true);
}
void
octave_qscintilla::contextmenu_help (bool)
{
  contextmenu_help_doc (false);
}

// common function with flag for documentation
void
octave_qscintilla::contextmenu_help_doc (bool documentation)
{
  if (documentation)
    emit show_doc_signal (_word_at_cursor);
  else
    emit execute_command_in_terminal_signal ("help " + _word_at_cursor);
}

void
octave_qscintilla::contextmenu_edit (bool)
{
  emit context_menu_edit_signal (_word_at_cursor);
}

void
octave_qscintilla::contextmenu_run (bool)
{
  QStringList commands = selectedText ().split (QRegExp("[\r\n]"),
                                                QString::SkipEmptyParts);
  for (int i = 0; i < commands.size (); i++)
    emit execute_command_in_terminal_signal (commands.at (i));
}

// wrappers for dbstop related context menu items

// FIXME: Why can't the data be sent as the argument to the function???
void
octave_qscintilla::contextmenu_break_condition (bool)
{
#if defined (HAVE_QSCI_VERSION_2_6_0)
  QAction *action = qobject_cast<QAction *>(sender());
  QPoint local_pos = action->data ().value<QPoint> ();

  // pick point just right of margins, so lineAt doesn't give -1
  int margins = marginWidth (1) + marginWidth (2) + marginWidth (3);
  local_pos = QPoint (margins + 1, local_pos.y ());

  emit context_menu_break_condition_signal (lineAt (local_pos));
#endif
}

void
octave_qscintilla::contextmenu_break_once (const QPoint& local_pos)
{
#if defined (HAVE_QSCI_VERSION_2_6_0)
  emit context_menu_break_once (lineAt (local_pos));
#endif
}

void
octave_qscintilla::text_changed ()
{
  emit status_update (isUndoAvailable (), isRedoAvailable ());
}

// when edit area gets focus update information on undo/redo actions
void octave_qscintilla::focusInEvent(QFocusEvent *focusEvent)
{
  emit status_update (isUndoAvailable (), isRedoAvailable ());

  QsciScintilla::focusInEvent(focusEvent);
}

#endif

