////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2011-2020 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// 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 (HAVE_CONFIG_H)
#  include "config.h"
#endif

#include <QEvent>
#include <QKeyEvent>
#include <QMouseEvent>
#include <QWidget>

#include "BaseControl.h"
#include "ContextMenu.h"
#include "QtHandlesUtils.h"

#include "graphics.h"
#include "interpreter.h"

namespace QtHandles
{

  static void
  updatePalette (const uicontrol::properties& props, QWidget *w)
  {
    QPalette p = w->palette ();

    if (props.style_is ("edit")
        || props.style_is ("listbox"))
      {
        p.setColor (QPalette::Active, QPalette::Base,
                    Utils::fromRgb (props.get_backgroundcolor_rgb ()));
        p.setColor (QPalette::Inactive, QPalette::Base,
                    Utils::fromRgb (props.get_backgroundcolor_rgb ()));
        p.setColor (QPalette::Active, QPalette::Text,
                    Utils::fromRgb (props.get_foregroundcolor_rgb ()));
        p.setColor (QPalette::Inactive, QPalette::Text,
                    Utils::fromRgb (props.get_foregroundcolor_rgb ()));
      }
    else if (props.style_is ("popupmenu"))
      {
        // popupmenu (QComboBox) is a listbox with a button.
        // This requires setting colors for both.
        QColor bcol = Utils::fromRgb (props.get_backgroundcolor_rgb ());
        QColor fcol = Utils::fromRgb (props.get_foregroundcolor_rgb ());
        QString qss = QString (":enabled { background: %1 none;\n"
                                          "color: %2; }")
                      .arg(bcol.name ()).arg (fcol.name ());
        w->setStyleSheet(qss);
        return;
      }
    else if (props.style_is ("radiobutton")
             || props.style_is ("checkbox"))
      {
        p.setColor (QPalette::Active, QPalette::Button,
                    Utils::fromRgb (props.get_backgroundcolor_rgb ()));
        p.setColor (QPalette::Inactive, QPalette::Button,
                    Utils::fromRgb (props.get_backgroundcolor_rgb ()));
        p.setColor (QPalette::Active, QPalette::WindowText,
                    Utils::fromRgb (props.get_foregroundcolor_rgb ()));
        p.setColor (QPalette::Inactive, QPalette::WindowText,
                    Utils::fromRgb (props.get_foregroundcolor_rgb ()));
      }
    else if (props.style_is ("pushbutton")
             || props.style_is ("togglebutton"))
      {
        QColor bcol = Utils::fromRgb (props.get_backgroundcolor_rgb ());
        QColor fcol = Utils::fromRgb (props.get_foregroundcolor_rgb ());
        QString qss = QString (":enabled { background: %1 none;\n"
                                          "color: %2; }")
                      .arg(bcol.name ()).arg (fcol.name ());
        w->setStyleSheet(qss);
        return;
      }
    else
      {
        p.setColor (QPalette::Window,
                    Utils::fromRgb (props.get_backgroundcolor_rgb ()));
        p.setColor (QPalette::WindowText,
                    Utils::fromRgb (props.get_foregroundcolor_rgb ()));
      }

    w->setPalette (p);
  }

  BaseControl::BaseControl (octave::base_qobject& oct_qobj,
                            octave::interpreter& interp,
                            const graphics_object& go, QWidget *w)
    : Object (oct_qobj, interp, go, w), m_normalizedFont (false),
      m_keyPressHandlerDefined (false)
  {
    qObject ()->setObjectName ("UIControl");
    init (w);
  }

  void
  BaseControl::init (QWidget *w, bool callBase)
  {
    if (callBase)
      Object::init (w, callBase);

    uicontrol::properties& up = properties<uicontrol> ();

    Matrix bb = up.get_boundingbox (false);
    w->setGeometry (octave::math::round (bb(0)), octave::math::round (bb(1)),
                    octave::math::round (bb(2)), octave::math::round (bb(3)));
    w->setFont (Utils::computeFont<uicontrol> (up, bb(3)));
    updatePalette (up, w);
    if (up.enable_is ("inactive"))
      w->blockSignals (true);
    else
      w->setEnabled (up.enable_is ("on"));
    w->setToolTip (Utils::fromStdString (up.get_tooltipstring ()));
    w->setVisible (up.is_visible ());
    m_keyPressHandlerDefined = ! up.get_keypressfcn ().isempty ();

    w->installEventFilter (this);

    m_normalizedFont = up.fontunits_is ("normalized");
  }

  BaseControl::~BaseControl (void)
  { }

  void
  BaseControl::redraw (void)
  {
    update (uicontrol::properties::ID_POSITION);
  }

  void
  BaseControl::update (int pId)
  {
    uicontrol::properties& up = properties<uicontrol> ();
    QWidget *w = qWidget<QWidget> ();

    switch (pId)
      {
      case uicontrol::properties::ID_POSITION:
        {
          Matrix bb = up.get_boundingbox (false);
          w->setGeometry (octave::math::round (bb(0)), octave::math::round (bb(1)),
                          octave::math::round (bb(2)), octave::math::round (bb(3)));
        }
        break;

      case uicontrol::properties::ID_FONTNAME:
      case uicontrol::properties::ID_FONTSIZE:
      case uicontrol::properties::ID_FONTWEIGHT:
      case uicontrol::properties::ID_FONTANGLE:
        w->setFont (Utils::computeFont<uicontrol> (up));
        break;

      case uicontrol::properties::ID_FONTUNITS:
        // FIXME: We shouldn't have to do anything, octave should update
        //        the "fontsize" property automatically to the new units.
        //        Hence the actual font used shouldn't change.
        m_normalizedFont = up.fontunits_is ("normalized");
        break;

      case uicontrol::properties::ID_BACKGROUNDCOLOR:
      case uicontrol::properties::ID_FOREGROUNDCOLOR:
        updatePalette (up, w);
        break;

      case uicontrol::properties::ID_ENABLE:
        if (up.enable_is ("inactive"))
          {
            w->blockSignals (true);
            w->setEnabled (true);
          }
        else
          {
            w->blockSignals (false);
            w->setEnabled (up.enable_is ("on"));
          }
        break;

      case uicontrol::properties::ID_TOOLTIPSTRING:
        w->setToolTip (Utils::fromStdString (up.get_tooltipstring ()));
        break;

      case base_properties::ID_VISIBLE:
        w->setVisible (up.is_visible ());
        break;

      case uicontrol::properties::ID_KEYPRESSFCN:
        m_keyPressHandlerDefined = ! up.get_keypressfcn ().isempty ();
        break;

      case uicontrol::properties::ID___FOCUS__:
        if (up.is___focus__ ())
          w->setFocus ();
        else
          w->clearFocus ();
        break;

      default:
        break;
      }
  }

  bool
  BaseControl::eventFilter (QObject *watched, QEvent *xevent)
  {
    gh_manager& gh_mgr = m_interpreter.get_gh_manager ();

    switch (xevent->type ())
      {
      case QEvent::Resize:
        if (m_normalizedFont)
          {
            octave::autolock guard (gh_mgr.graphics_lock ());

            qWidget<QWidget> ()->setFont (Utils::computeFont<uicontrol>
                                          (properties<uicontrol> ()));
          }
        break;

      case QEvent::MouseButtonPress:
        {
          octave::autolock guard (gh_mgr.graphics_lock ());

          QMouseEvent *m = dynamic_cast<QMouseEvent *> (xevent);
          graphics_object go = object ();
          uicontrol::properties& up = Utils::properties<uicontrol> (go);
          graphics_object fig = go.get_ancestor ("figure");
          if (fig)
            {
              emit gh_set_event (fig.get_handle (), "currentobject",
                                 m_handle.value (), false);

              if (m->button () != Qt::LeftButton || ! up.enable_is ("on"))
                {
                  emit gh_set_event (fig.get_handle (), "selectiontype",
                                     Utils::figureSelectionType (m), false);
                  emit gh_set_event (fig.get_handle (), "currentpoint",
                                     Utils::figureCurrentPoint (fig, m),
                                     false);
                  emit gh_callback_event (fig.get_handle (),
                                          "windowbuttondownfcn");
                  emit gh_callback_event (m_handle, "buttondownfcn");

                  if (m->button () == Qt::RightButton)
                    ContextMenu::executeAt (m_interpreter, up, m->globalPos ());
                }
              else
                {
                  if (up.style_is ("listbox"))
                    emit gh_set_event (fig.get_handle (), "selectiontype",
                                       Utils::figureSelectionType (m),
                                       false);
                  else
                    emit gh_set_event (fig.get_handle (), "selectiontype",
                                       octave_value ("normal"), false);
                }
            }
        }
        break;

      case QEvent::MouseMove:
        if (qWidget<QWidget> ()->hasMouseTracking ())
          {
            octave::autolock guard (gh_mgr.graphics_lock ());

            QMouseEvent *m = dynamic_cast<QMouseEvent *> (xevent);
            graphics_object go = object ();
            graphics_object fig = go.get_ancestor ("figure");

            if (fig)
              {
                emit gh_set_event (fig.get_handle (), "currentpoint",
                                   Utils::figureCurrentPoint (fig, m), false);
                emit gh_callback_event (fig.get_handle (),
                                        "windowbuttonmotionfcn");
              }
          }
        break;

      case QEvent::KeyPress:
        if (m_keyPressHandlerDefined)
          {
            octave::autolock guard (gh_mgr.graphics_lock ());

            octave_scalar_map keyData =
              Utils::makeKeyEventStruct (dynamic_cast<QKeyEvent *> (xevent));
            graphics_object fig = object ().get_ancestor ("figure");

            emit gh_set_event (fig.get_handle (), "currentcharacter",
                               keyData.getfield ("Character"), false);
            emit gh_callback_event (m_handle, "keypressfcn", keyData);
          }
        break;

      case QEvent::FocusIn:
        emit gh_set_event (m_handle, "__focus__", "on", false);
        break;

      case QEvent::FocusOut:
        emit gh_set_event (m_handle, "__focus__", "off", false);
        break;

      default:
        break;
      }

    return Object::eventFilter (watched, xevent);
  }

}