////////////////////////////////////////////////////////////////////////
//
// 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 <list>

#include <QApplication>
#include <QKeyEvent>
#include <QMouseEvent>

#include "Container.h"
#include "KeyMap.h"
#include "Object.h"
#include "QtHandlesUtils.h"
#include "qt-graphics-toolkit.h"

#include "oct-string.h"

#include "graphics.h"
#include "ov.h"

namespace QtHandles
{

  namespace Utils
  {

    QString
    fromStdString (const std::string& s)
    {
      return QString::fromUtf8 (s.c_str ());
    }

    std::string
    toStdString (const QString& s)
    {
      return std::string (s.toUtf8 ().data ());
    }

    QStringList
    fromStringVector (const string_vector& v)
    {
      QStringList l;
      octave_idx_type n = v.numel ();

      for (octave_idx_type i = 0; i < n; i++)
        l << fromStdString (v[i]);

      return l;
    }

    string_vector
    toStringVector (const QStringList& l)
    {
      string_vector v (l.length ());
      int i = 0;

      for (const auto& s : l)
        v[i++] = toStdString (s);

      return v;
    }

    Cell toCellString (const QStringList& l)
    {
      QStringList tmp = l;

      // don't get any empty lines from end of the list
      while ((tmp.length () > 0) && tmp.last ().isEmpty ())
        {
          tmp.removeLast ();
        }
      // no strings converts to a 1x1 cell with empty string
      if (tmp.isEmpty ())
        tmp += "";

      Cell v (toStringVector (tmp));
      return v;
    }

    template <typename T>
    QFont
    computeFont (const typename T::properties& props, int height)
    {
      QFont f (fromStdString (props.get_fontname ()));

      static std::map<std::string, QFont::Weight> weightMap;
      static std::map<std::string, QFont::Style> angleMap;
      static bool mapsInitialized = false;

      if (! mapsInitialized)
        {
          weightMap["normal"] = QFont::Normal;
          weightMap["bold"] = QFont::Bold;

          angleMap["normal"] = QFont::StyleNormal;
          angleMap["italic"] = QFont::StyleItalic;
          angleMap["oblique"] = QFont::StyleOblique;

          mapsInitialized = true;
        }

      f.setPointSizeF (props.get___fontsize_points__ (height));
      f.setWeight (weightMap[props.get_fontweight ()]);
      f.setStyle (angleMap[props.get_fontangle ()]);

      return f;
    }

    template QFont computeFont<uicontrol> (const uicontrol::properties& props,
                                           int height);

    template QFont computeFont<uipanel> (const uipanel::properties& props,
                                         int height);

    template QFont computeFont<uibuttongroup> (const uibuttongroup::properties&
        props,
        int height);

    template QFont computeFont<uitable> (const uitable::properties& props,
                                         int height);

    QColor
    fromRgb (const Matrix& rgb)
    {
      QColor c;

      if (rgb.numel () == 3)
        c.setRgbF (rgb(0), rgb(1), rgb(2));

      return c;
    }

    Matrix
    toRgb (const QColor& c)
    {
      Matrix rgb (1, 3);
      double *rgbData = rgb.fortran_vec ();

      // qreal is a typedef for double except for ARM CPU architectures
      // where it is a typedef for float (Bug #44970).
      qreal tmp[3];
      c.getRgbF (tmp, tmp+1, tmp+2);
      rgbData[0] = tmp[0]; rgbData[1] = tmp[1]; rgbData[2] = tmp[2];

      return rgb;
    }

    std::string
    figureSelectionType (QMouseEvent *event, bool isDoubleClick)
    {
      if (isDoubleClick)
        return "open";
      else
        {
          Qt::MouseButtons buttons = event->buttons ();
          Qt::KeyboardModifiers mods = event->modifiers ();

          if (mods == Qt::NoModifier)
            {
              if (buttons == Qt::LeftButton)
                return "normal";
              else if (buttons == Qt::RightButton)
                return "alt";
              else if (buttons == Qt::MidButton
                       || buttons == (Qt::LeftButton | Qt::RightButton))
                return "extend";
            }
          else if (buttons == Qt::LeftButton)
            {
              if (mods == Qt::ShiftModifier)
                return "extend";
              else if (mods == Qt::ControlModifier)
                return "alt";
            }
        }

      return "normal";
    }

    /*
       Two figureCurrentPoint() routines are required:
       1) Used for QMouseEvents where cursor position data is in callback from Qt.
       2) Used for QKeyEvents where cursor position must be determined.
    */
    Matrix
    figureCurrentPoint (const graphics_object& fig, QMouseEvent *event)
    {
      Object *tkFig = qt_graphics_toolkit::toolkitObject (fig);

      if (tkFig)
        {
          Container *c = tkFig->innerContainer ();

          if (c)
            {
              QPoint qp = c->mapFromGlobal (event->globalPos ());

              return tkFig->properties<figure> ().map_from_boundingbox (qp.x (),
                     qp.y ());
            }
        }

      return Matrix (1, 2, 0.0);
    }

    Matrix
    figureCurrentPoint (const graphics_object& fig)
    {
      Object *tkFig = qt_graphics_toolkit::toolkitObject (fig);

      if (tkFig)
        {
          Container *c = tkFig->innerContainer ();

          if (c)
            {
              // FIXME: QCursor::pos() may give inaccurate results with
              //        asynchronous window systems like X11 over ssh.
              QPoint qp = c->mapFromGlobal (QCursor::pos ());

              return tkFig->properties<figure> ().map_from_boundingbox (qp.x (),
                     qp.y ());
            }
        }

      return Matrix (1, 2, 0.0);
    }

    Qt::Alignment
    fromHVAlign (const std::string& halign, const std::string& valign)
    {
      Qt::Alignment flags;

      if (octave::string::strcmpi (halign, "left"))
        flags |= Qt::AlignLeft;
      else if (octave::string::strcmpi (halign, "center"))
        flags |= Qt::AlignHCenter;
      else if (octave::string::strcmpi (halign, "right"))
        flags |= Qt::AlignRight;
      else
        flags |= Qt::AlignLeft;

      if (octave::string::strcmpi (valign, "middle"))
        flags |= Qt::AlignVCenter;
      else if (octave::string::strcmpi (valign, "top"))
        flags |= Qt::AlignTop;
      else if (octave::string::strcmpi (valign, "bottom"))
        flags |= Qt::AlignBottom;
      else
        flags |= Qt::AlignVCenter;

      return flags;
    }

    QImage
    makeImageFromCData (const octave_value& v, int width, int height)
    {
      dim_vector dv (v.dims ());

      if (dv.ndims () == 3 && dv(2) == 3)
        {
          int w = qMin (dv(1), static_cast<octave_idx_type> (width));
          int h = qMin (dv(0), static_cast<octave_idx_type> (height));

          // If size mismatch, take data from center of CDATA and
          // place in in center of QImage.
          int x_img_off = (w < width ? (width - w) / 2 : 0);
          int y_img_off = (h < height ? (height - h) / 2 : 0);
          int x_cdat_off = (dv(1) > w ? (dv(1) - w) / 2 : 0);
          int y_cdat_off = (dv(0) > h ? (dv(0) - h) / 2 : 0);

          QImage img (width, height, QImage::Format_ARGB32);
          img.fill (qRgba (0, 0, 0, 0));

          if (v.is_uint8_type ())
            {
              uint8NDArray d = v.uint8_array_value ();

              for (int i = x_cdat_off; i < w + x_cdat_off; i++)
                for (int j = y_cdat_off; j < h + y_cdat_off; j++)
                  {
                    int r = d(j, i, 0);
                    int g = d(j, i, 1);
                    int b = d(j, i, 2);
                    int a = 255;

                    img.setPixel (x_img_off + i - x_cdat_off,
                                  y_img_off + j - y_cdat_off,
                                  qRgba (r, g, b, a));
                  }
            }
          else if (v.is_single_type ())
            {
              FloatNDArray f = v.float_array_value ();

              for (int i = x_cdat_off; i < w + x_cdat_off; i++)
                for (int j = y_cdat_off; j < h + y_cdat_off; j++)
                  {
                    float r = f(j, i, 0);
                    float g = f(j, i, 1);
                    float b = f(j, i, 2);
                    int a = (octave::math::isnan (r) || octave::math::isnan (g)
                             || octave::math::isnan (b) ? 0 : 255);

                    img.setPixel (x_img_off + i - x_cdat_off,
                                  y_img_off + j - y_cdat_off,
                                  qRgba (octave::math::round (r * 255),
                                         octave::math::round (g * 255),
                                         octave::math::round (b * 255),
                                         a));
                  }
            }
          else if (v.isreal ())
            {
              NDArray d = v.array_value ();

              for (int i = x_cdat_off; i < w + x_cdat_off; i++)
                for (int j = y_cdat_off; j < h + y_cdat_off; j++)
                  {
                    double r = d(j, i, 0);
                    double g = d(j, i, 1);
                    double b = d(j, i, 2);
                    int a = (octave::math::isnan (r) || octave::math::isnan (g)
                             || octave::math::isnan (b) ? 0 : 255);

                    img.setPixel (x_img_off + i - x_cdat_off,
                                  y_img_off + j - y_cdat_off,
                                  qRgba (octave::math::round (r * 255),
                                         octave::math::round (g * 255),
                                         octave::math::round (b * 255),
                                         a));
                  }
            }

          return img;
        }

      return QImage ();
    }

    octave_scalar_map
    makeKeyEventStruct (QKeyEvent *event)
    {
      octave_scalar_map retval;

      retval.setfield ("Key", KeyMap::qKeyToKeyString (event->key ()));
      retval.setfield ("Character", toStdString (event->text ()));

      std::list<std::string> modList;
      Qt::KeyboardModifiers mods = event->modifiers ();

      if (mods & Qt::ShiftModifier)
        modList.push_back ("shift");
      if (mods & Qt::ControlModifier)
#if defined (Q_OS_MAC)
        modList.push_back ("command");
#else
        modList.push_back ("control");
#endif
      if (mods & Qt::AltModifier)
        modList.push_back ("alt");
#if defined (Q_OS_MAC)
      if (mods & Qt::MetaModifier)
        modList.push_back ("control");
#endif

      retval.setfield ("Modifier", Cell (modList));

      return retval;
    }

    octave_scalar_map
    makeScrollEventStruct (QWheelEvent *event)
    {
      octave_scalar_map retval;

      // We assume a standard mouse with 15 degree steps and Qt returns
      // 1/8 of a degree.
#if defined (HAVE_QWHEELEVENT_ANGLEDELTA)
      int ydelta = -(event->angleDelta().y ());
#else
      int ydelta = (event->orientation () == Qt::Vertical
                    ? -(event->delta ()) : 0);
#endif
      retval.setfield ("VerticalScrollCount", octave_value (ydelta / 120));

      // FIXME: Is there any way to access the number of lines a scroll step
      // should correspond to?
      retval.setfield ("VerticalScrollAmount", octave_value (3));
      retval.setfield ("EventName", octave_value ("WindowScrollWheel"));

      return retval;
    }

  }

}