/////////////////////////////////////////////////////////////////////////////
// Name:        src/qt/dcclient.cpp
// Author:      Peter Most, Javier Torres, Mariano Reingart
// Copyright:   (c) 2010 wxWidgets dev team
// Licence:     wxWindows licence
/////////////////////////////////////////////////////////////////////////////

// For compilers that support precompilation, includes "wx.h".
#include "wx/wxprec.h"

#ifdef __BORLANDC__
    #pragma hdrstop
#endif

#include <QtGui/QPicture>

#ifndef WX_PRECOMP
    #include "wx/log.h"
    #include "wx/window.h"
#endif // WX_PRECOMP

#include "wx/dcclient.h"
#include "wx/qt/dcclient.h"

#include <QtWidgets/QScrollArea>
#include <QtGui/QPainter>

//##############################################################################

namespace
{
class QtPictureSetter
{
public:
    QtPictureSetter(wxWindow *window, QPicture *pict)
        : m_window( window )
    {
        m_window->QtSetPicture( pict );
    }

    ~QtPictureSetter()
    {
        m_window->QtSetPicture( NULL );
    }

private:
    wxWindow* const m_window;

    wxDECLARE_NO_COPY_CLASS(QtPictureSetter);
};
}


wxIMPLEMENT_CLASS(wxWindowDCImpl,wxQtDCImpl);

wxWindowDCImpl::wxWindowDCImpl( wxDC *owner )
    : wxQtDCImpl( owner )
{
    m_window = NULL;
    m_ok = false;
    m_qtPainter = new QPainter();
}

wxWindowDCImpl::wxWindowDCImpl( wxDC *owner, wxWindow *win )
    : wxQtDCImpl( owner )
{
    m_window = win;
    m_qtPainter = m_window->QtGetPainter();
    // if we're not inside a Paint event, painter will invalid
    m_ok = m_qtPainter != NULL;
}

wxWindowDCImpl::~wxWindowDCImpl()
{
    if ( m_ok )
    {
        m_ok = false;
    }
    if ( m_window )
    {
        // do not destroy in base class as it is owned by the window
        m_qtPainter = NULL;
    }
}

//##############################################################################

wxIMPLEMENT_CLASS(wxClientDCImpl,wxWindowDCImpl);

wxClientDCImpl::wxClientDCImpl( wxDC *owner )
    : wxWindowDCImpl( owner )
{
    m_window = NULL;
    m_qtPainter = NULL;
}

wxClientDCImpl::wxClientDCImpl( wxDC *owner, wxWindow *win )
    : wxWindowDCImpl( owner )
{
    m_window = win;

    m_qtPainter = new QPainter();

    m_pict.reset(new QPicture());
    m_ok = m_qtPainter->begin( m_pict.get() );

    QtPreparePainter();
}

wxClientDCImpl::~wxClientDCImpl()
{
    /* Paint to a QPicture that will then be painted in the next
     * paint event of that window (a paint event will be generated
     * when this wxClientDC is done). */
    if ( m_ok )
    {
        m_qtPainter->end();
        m_ok = false;

        if ( m_window != NULL )
        {
            QtPictureSetter pictureSetter(m_window, m_pict.get());

            // get the inner widget in scroll areas:
            QWidget *widget;
            if ( m_window->QtGetScrollBarsContainer() )
            {
                widget = m_window->QtGetScrollBarsContainer()->viewport();
            } else {
                widget = m_window->GetHandle();
            }
            // force paint event if there is something to replay and
            // if not currently inside a paint event (to avoid recursion)
            QRect rect = m_pict->boundingRect();
            if ( !m_pict->isNull() && !widget->paintingActive() && !rect.isEmpty() )
            {
                // only force the update of the rect affected by the DC
                widget->update( rect );
            }
            else
            {
                // Not drawing anything, reset picture to avoid issues in handler
                m_pict->setData( NULL, 0 );
            }

            // let destroy the m_qtPainter (see inherited classes destructors)
            m_window = NULL;
        }
    }

    // Painter will be deleted by base class
}

//##############################################################################

wxIMPLEMENT_CLASS(wxPaintDCImpl,wxClientDCImpl);

wxPaintDCImpl::wxPaintDCImpl( wxDC *owner )
    : wxWindowDCImpl( owner )
{
    if ( m_ok )
    {
        QtPreparePainter();
    }
}

wxPaintDCImpl::wxPaintDCImpl( wxDC *owner, wxWindow *win )
    : wxWindowDCImpl( owner, win )
{
    if ( m_ok )
    {
        QtPreparePainter();
    }
}