//=========================================================
//  MusE
//  Linux Music Editor
//  vst_native_editor.cpp
//  (C) Copyright 2012 Tim E. Real (terminator356 on users dot sourceforge dot net)
//  Some of the editor window coding was adapted from QTractor (by rncbc aka Rui Nuno Capela)
//
//  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; version 2 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, write to the Free Software
//  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
//
//=========================================================

#include "config.h"

#ifdef VST_NATIVE_SUPPORT

#include "vst_native_editor.h"
#include "vst_native.h"

#include <QtGlobal>
#if defined(Q_WS_X11)
#include <QX11Info>
#endif

namespace MusEGui {

//---------------------------------------------------------------------
// Helpers for editor widget.
//---------------------------------------------------------------------

#if defined(Q_WS_X11)

static bool g_bXError = false;

static int tempXErrorHandler ( Display *, XErrorEvent * )
{
        g_bXError = true;
        return 0;
}

static XEventProc getXEventProc ( Display *pDisplay, Window w )
{
        int iSize;
        unsigned long iBytes, iCount;
        unsigned char *pData;
        XEventProc eventProc = NULL;
        Atom aType, aName = XInternAtom(pDisplay, "_XEventProc", false);

        g_bXError = false;
        XErrorHandler oldErrorHandler = XSetErrorHandler(tempXErrorHandler);
        XGetWindowProperty(pDisplay, w, aName, 0, 1, false,
                AnyPropertyType, &aType,  &iSize, &iCount, &iBytes, &pData);
        if (g_bXError == false && iCount == 1)
                eventProc = (XEventProc) (pData);
        XSetErrorHandler(oldErrorHandler);

        return eventProc;
}

static Window getXChildWindow ( Display *pDisplay, Window w )
{
        Window wRoot, wParent, *pwChildren;
        unsigned int iChildren = 0;

        XQueryTree(pDisplay, w, &wRoot, &wParent, &pwChildren, &iChildren);

        return (iChildren > 0 ? pwChildren[0] : 0);
}

#endif // Q_WS_X11

VstNativeEditor::VstNativeEditor(QWidget *parent, Qt::WindowFlags wflags)
  : QWidget(parent, wflags),
        #if defined(Q_WS_X11)
          _display(QX11Info::display()),
          _vstEditor(0),
          _vstEventProc(0),
          _buttonPress(false),
        #endif
          _sif(0)
{
  setAttribute(Qt::WA_DeleteOnClose);
  
  // TODO TEST Test if these might be helpful, especially opaque event.
            //setBackgroundRole(QPalette::NoRole);
            //setAttribute(Qt::WA_NoSystemBackground);
  //         setAttribute(Qt::WA_StaticContents);
  //         // This is absolutely required for speed! Otherwise painfully slow because of full background
  //         //  filling, even when requesting small udpdates! Background is drawn by us.
            //setAttribute(Qt::WA_OpaquePaintEvent);
  //         //setFrameStyle(QFrame::Raised | QFrame::StyledPanel);
}

VstNativeEditor::~VstNativeEditor()
{
  if(_sif)
  {
    _sif->dispatch(effEditClose, 0, 0, NULL, 0.0f);
    _sif->editorDeleted();
    _sif = NULL;
  }
}

//---------------------------------------------------------------------
// open
//---------------------------------------------------------------------

void VstNativeEditor::open(MusECore::VstNativeSynthIF* sif)
{
  _sif = sif;

  // Start the proper (child) editor...
  long  value = 0;
  void *ptr = (void *) winId();
#if defined(Q_WS_X11)
  value = (long) _display;
#endif

  MusECore::VstRect* pRect;
  if(_sif->dispatch(effEditGetRect, 0, 0, &pRect, 0.0f))   
  {
          int w = pRect->right - pRect->left;
          int h = pRect->bottom - pRect->top;
          if (w > 0 && h > 0)
                  QWidget::setFixedSize(w, h);
  }

  _sif->dispatch(effEditOpen, 0, value, ptr, 0.0f);
  //int rv = _sif->dispatch(effEditOpen, 0, value, ptr, 0.0f);
  //fprintf(stderr, "VstNativeEditor::open effEditOpen returned:%d effEditGetRect rect l:%d r:%d t:%d b:%d\n", rv, pRect->left, pRect->right, pRect->top, pRect->bottom); // REMOVE Tim.
  
#if defined(Q_WS_X11)
  _vstEditor = getXChildWindow(_display, (Window) winId());
  if(_vstEditor)
    _vstEventProc = getXEventProc(_display, _vstEditor);
#endif
    
  if(_sif->track())
  {
    QString title = _sif->track()->name() + ":" + _sif->pluginLabel();
    setWindowTitle(title);
  }

  //_sif->editorOpened();
  if(!isVisible())
    show();
  raise();
  activateWindow();
  ///_sif->idleEditor();  // REMOVE Tim. Or keep.
}

#if defined(Q_WS_X11)

//---------------------------------------------------------------------
// x11EventFilter
//---------------------------------------------------------------------

bool VstNativeEditor::x11EventFilter(XEvent *pEvent)
{
  if(_vstEventProc && pEvent->xany.window == _vstEditor)
  {
    // Avoid mouse tracking events...
    switch (pEvent->xany.type) {
    case ButtonPress:
      _buttonPress = true;
      break;
    case ButtonRelease:
      _buttonPress = false;
      break;
    case MotionNotify:
      if(!_buttonPress)
        return false;
      // Fall thru...
    default:
      break;
    }
    // Process as intended...
    (*_vstEventProc)(pEvent);
    return true;
  }
  else
    return false;
}

#endif

//---------------------------------------------------------------------
// showEvent
//---------------------------------------------------------------------

void VstNativeEditor::showEvent(QShowEvent *pShowEvent)
{
  QWidget::showEvent(pShowEvent);

  if(_sif)
    _sif->editorOpened();
}

//---------------------------------------------------------------------
// closeEvent
//---------------------------------------------------------------------

void VstNativeEditor::closeEvent(QCloseEvent *pCloseEvent)
{
  if(_sif)
    _sif->editorClosed();
    
  QWidget::closeEvent(pCloseEvent);
}

//---------------------------------------------------------------------
// moveEvent
//---------------------------------------------------------------------

void VstNativeEditor::moveEvent(QMoveEvent *pMoveEvent)
{
  QWidget::moveEvent(pMoveEvent);
#if defined(Q_WS_X11)
  if(_vstEditor)
  {
    XMoveWindow(_display, _vstEditor, 0, 0);
    //QWidget::update();  // REMOVE Tim. Or keep? Commented in Qtractor.
  }
#endif
}

} // namespace MusEGui

#endif // VST_NATIVE_SUPPORT