/////////////////////////////////////////////////////////////////////////////
// Name:        src/gtk/cursor.cpp
// Purpose:     wxCursor implementation
// Author:      Robert Roebling
// Id:          $Id: cursor.cpp 66371 2010-12-14 18:43:25Z VZ $
// Copyright:   (c) 1998 Robert Roebling
// Licence:     wxWindows licence
/////////////////////////////////////////////////////////////////////////////

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

#include "wx/cursor.h"

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

#include <gtk/gtk.h>
#include "wx/gtk/private/object.h"

//-----------------------------------------------------------------------------
// wxCursorRefData
//-----------------------------------------------------------------------------

class wxCursorRefData: public wxGDIRefData
{
public:
    wxCursorRefData();
    virtual ~wxCursorRefData();

    virtual bool IsOk() const { return m_cursor != NULL; }

    GdkCursor *m_cursor;

private:
    // There is no way to copy m_cursor so we can't implement a copy ctor
    // properly.
    wxDECLARE_NO_COPY_CLASS(wxCursorRefData);
};

wxCursorRefData::wxCursorRefData()
{
    m_cursor = NULL;
}

wxCursorRefData::~wxCursorRefData()
{
    if (m_cursor) gdk_cursor_unref( m_cursor );
}


//-----------------------------------------------------------------------------
// wxCursor
//-----------------------------------------------------------------------------

#define M_CURSORDATA static_cast<wxCursorRefData*>(m_refData)

IMPLEMENT_DYNAMIC_CLASS(wxCursor, wxGDIObject)

// used in the following two ctors
extern GtkWidget *wxGetRootWindow();


wxCursor::wxCursor()
{
}

#if wxUSE_IMAGE
wxCursor::wxCursor(const wxString& cursor_file,
                   wxBitmapType type,
                   int hotSpotX, int hotSpotY)
{
    wxImage img;
    if (!img.LoadFile(cursor_file, type))
        return;

    // eventually set the hotspot:
    if (!img.HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_X))
        img.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, hotSpotX);
    if (!img.HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y))
        img.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y, hotSpotY);

    InitFromImage(img);
}

wxCursor::wxCursor(const wxImage& img)
{
    InitFromImage(img);
}
#endif

wxCursor::wxCursor(const char bits[], int width, int height,
                   int hotSpotX, int hotSpotY,
                   const char maskBits[], const wxColour *fg, const wxColour *bg)
{
    if (!maskBits)
        maskBits = bits;
    if (!fg)
        fg = wxBLACK;
    if (!bg)
        bg = wxWHITE;
    if (hotSpotX < 0 || hotSpotX >= width)
        hotSpotX = 0;
    if (hotSpotY < 0 || hotSpotY >= height)
        hotSpotY = 0;

    GdkBitmap *data = gdk_bitmap_create_from_data( wxGetRootWindow()->window, (gchar *) bits, width, height );
    GdkBitmap *mask = gdk_bitmap_create_from_data( wxGetRootWindow()->window, (gchar *) maskBits, width, height);

    m_refData = new wxCursorRefData;
    M_CURSORDATA->m_cursor = gdk_cursor_new_from_pixmap(
                 data, mask, fg->GetColor(), bg->GetColor(),
                 hotSpotX, hotSpotY );

    g_object_unref (data);
    g_object_unref (mask);
}

wxCursor::~wxCursor()
{
}

void wxCursor::InitFromStock( wxStockCursor cursorId )
{
    m_refData = new wxCursorRefData();

    GdkCursorType gdk_cur = GDK_LEFT_PTR;
    switch (cursorId)
    {
        case wxCURSOR_BLANK:
            {
                const char bits[] = { 0 };
                const GdkColor color = { 0, 0, 0, 0 };

                GdkPixmap *pixmap = gdk_bitmap_create_from_data(NULL, bits, 1, 1);
                M_CURSORDATA->m_cursor = gdk_cursor_new_from_pixmap(pixmap,
                                                                    pixmap,
                                                                    &color,
                                                                    &color,
                                                                    0, 0);
                g_object_unref(pixmap);
            }
            return;

        case wxCURSOR_ARROW:            // fall through to default
        case wxCURSOR_DEFAULT:          gdk_cur = GDK_LEFT_PTR; break;
        case wxCURSOR_RIGHT_ARROW:      gdk_cur = GDK_RIGHT_PTR; break;
        case wxCURSOR_HAND:             gdk_cur = GDK_HAND2; break;
        case wxCURSOR_CROSS:            gdk_cur = GDK_CROSSHAIR; break;
        case wxCURSOR_SIZEWE:           gdk_cur = GDK_SB_H_DOUBLE_ARROW; break;
        case wxCURSOR_SIZENS:           gdk_cur = GDK_SB_V_DOUBLE_ARROW; break;
        case wxCURSOR_ARROWWAIT:
        case wxCURSOR_WAIT:
        case wxCURSOR_WATCH:            gdk_cur = GDK_WATCH; break;
        case wxCURSOR_SIZING:           gdk_cur = GDK_SIZING; break;
        case wxCURSOR_SPRAYCAN:         gdk_cur = GDK_SPRAYCAN; break;
        case wxCURSOR_IBEAM:            gdk_cur = GDK_XTERM; break;
        case wxCURSOR_PENCIL:           gdk_cur = GDK_PENCIL; break;
        case wxCURSOR_NO_ENTRY:         gdk_cur = GDK_PIRATE; break;
        case wxCURSOR_SIZENWSE:
        case wxCURSOR_SIZENESW:         gdk_cur = GDK_FLEUR; break;
        case wxCURSOR_QUESTION_ARROW:   gdk_cur = GDK_QUESTION_ARROW; break;
        case wxCURSOR_PAINT_BRUSH:      gdk_cur = GDK_SPRAYCAN; break;
        case wxCURSOR_MAGNIFIER:        gdk_cur = GDK_PLUS; break;
        case wxCURSOR_CHAR:             gdk_cur = GDK_XTERM; break;
        case wxCURSOR_LEFT_BUTTON:      gdk_cur = GDK_LEFTBUTTON; break;
        case wxCURSOR_MIDDLE_BUTTON:    gdk_cur = GDK_MIDDLEBUTTON; break;
        case wxCURSOR_RIGHT_BUTTON:     gdk_cur = GDK_RIGHTBUTTON; break;
        case wxCURSOR_BULLSEYE:         gdk_cur = GDK_TARGET; break;

        case wxCURSOR_POINT_LEFT:       gdk_cur = GDK_SB_LEFT_ARROW; break;
        case wxCURSOR_POINT_RIGHT:      gdk_cur = GDK_SB_RIGHT_ARROW; break;
/*
        case wxCURSOR_DOUBLE_ARROW:     gdk_cur = GDK_DOUBLE_ARROW; break;
        case wxCURSOR_CROSS_REVERSE:    gdk_cur = GDK_CROSS_REVERSE; break;
        case wxCURSOR_BASED_ARROW_UP:   gdk_cur = GDK_BASED_ARROW_UP; break;
        case wxCURSOR_BASED_ARROW_DOWN: gdk_cur = GDK_BASED_ARROW_DOWN; break;
*/

        default:
            wxFAIL_MSG(wxT("unsupported cursor type"));
            // will use the standard one
            break;
    }

    M_CURSORDATA->m_cursor = gdk_cursor_new( gdk_cur );
}

#if wxUSE_IMAGE

static void GetHotSpot(const wxImage& image, int& x, int& y)
{
    if (image.HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_X))
        x = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X);
    else
        x = 0;

    if (image.HasOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y))
        y = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_Y);
    else
        y = 0;

    if (x < 0 || x >= image.GetWidth())
        x = 0;
    if (y < 0 || y >= image.GetHeight())
        y = 0;
}

void wxCursor::InitFromImage( const wxImage & image )
{
    int w = image.GetWidth() ;
    int h = image.GetHeight();
    bool bHasMask = image.HasMask();
    int hotSpotX, hotSpotY;
    GetHotSpot(image, hotSpotX, hotSpotY);
    m_refData = new wxCursorRefData;
    wxImage image_copy(image);

    GdkDisplay* display = gdk_drawable_get_display(wxGetRootWindow()->window);
    if (gdk_display_supports_cursor_color(display))
    {
        if (!image.HasAlpha())
        {
            // add alpha, so wxBitmap will convert to pixbuf format
            image_copy.InitAlpha();
        }
        wxBitmap bitmap(image_copy);
        wxASSERT(bitmap.HasPixbuf());
        M_CURSORDATA->m_cursor = gdk_cursor_new_from_pixbuf
                             (
                              display,
                              bitmap.GetPixbuf(),
                              hotSpotX, hotSpotY
                             );
    }
    else // no colour cursor support
    {
        unsigned long keyMaskColor = 0;
        GdkPixmap *maskRaw;
        if (bHasMask)
        {
            keyMaskColor = wxImageHistogram::MakeKey(
                image.GetMaskRed(), image.GetMaskGreen(), image.GetMaskBlue());
            // get mask before image is modified
            wxBitmap bitmap(image, 1);
            maskRaw = bitmap.GetMask()->GetBitmap();
            g_object_ref(maskRaw);
        }
        else
        {
            const int size = ((w + 7) / 8) * h;
            char* bits = new char[size];
            memset(bits, 0xff, size);
            maskRaw = gdk_bitmap_create_from_data(
                wxGetRootWindow()->window, bits, w, h);
            delete[] bits;
        }

        // assign the raw pointer to wxGtkObject to ensure it is unref'd later
        wxGtkObject<GdkPixmap> mask(maskRaw);

        // modify image so wxBitmap can be used to convert to pixmap
        image_copy.SetMask(false);
        wxByte* data = image_copy.GetData();
        for (int j = 0; j < h; j++)
        {
            for (int i = 0; i < w; i++, data += 3)
            {
                // if average value of the pixel is > mid grey, convert it to
                // background (0), otherwise to foreground (255, using wxBitmap
                // convention)
                data[0] =
                data[1] =
                data[2] = int(data[0]) + data[1] + data[2] >= 3 * 128 ? 0 : 255;
            }
        }
        wxBitmap bitmap(image_copy, 1);

        // find the most frequent color(s)
        wxImageHistogram histogram;
        image.ComputeHistogram(histogram);

        long colMostFreq = 0;
        unsigned long nMost = 0;
        long colNextMostFreq = 0;
        unsigned long nNext = 0;
        for ( wxImageHistogram::iterator entry = histogram.begin();
              entry != histogram.end();
              ++entry )
        {
            unsigned long key = entry->first;
            if ( !bHasMask || (key != keyMaskColor) )
            {
                unsigned long value = entry->second.value;
                if (value > nMost)
                {
                    nNext = nMost;
                    colNextMostFreq = colMostFreq;
                    nMost = value;
                    colMostFreq = key;
                }
                else if (value > nNext)
                {
                    nNext = value;
                    colNextMostFreq = key;
                }
            }
        }

        wxColour fg = wxColour ( (unsigned char)(colMostFreq >> 16),
                                 (unsigned char)(colMostFreq >> 8),
                                 (unsigned char)(colMostFreq) );

        wxColour bg = wxColour ( (unsigned char)(colNextMostFreq >> 16),
                                 (unsigned char)(colNextMostFreq >> 8),
                                 (unsigned char)(colNextMostFreq) );

        int fg_intensity = fg.Red() + fg.Green() + fg.Blue();
        int bg_intensity = bg.Red() + bg.Green() + bg.Blue();

        if (bg_intensity > fg_intensity)
        {
            //swap fg and bg
            wxColour tmp = fg;
            fg = bg;
            bg = tmp;
        }

        M_CURSORDATA->m_cursor = gdk_cursor_new_from_pixmap
                                 (
                                    bitmap.GetPixmap(),
                                    mask,
                                    fg.GetColor(), bg.GetColor(),
                                    hotSpotX, hotSpotY
                                 );
    }
}

#endif // wxUSE_IMAGE

GdkCursor *wxCursor::GetCursor() const
{
    return M_CURSORDATA->m_cursor;
}

wxGDIRefData *wxCursor::CreateGDIRefData() const
{
    return new wxCursorRefData;
}

wxGDIRefData *
wxCursor::CloneGDIRefData(const wxGDIRefData * WXUNUSED(data)) const
{
    // TODO: We can't clone GDK cursors at the moment. To do this we'd need
    //       to remember the original data from which the cursor was created
    //       (i.e. standard cursor type or the bitmap) or use
    //       gdk_cursor_get_cursor_type() (which is in 2.22+ only) and
    //       gdk_cursor_get_image().
    wxFAIL_MSG( wxS("Cloning cursors is not implemented in wxGTK.") );

    return new wxCursorRefData;
}

//-----------------------------------------------------------------------------
// busy cursor routines
//-----------------------------------------------------------------------------

/* Current cursor, in order to hang on to
 * cursor handle when setting the cursor globally */
wxCursor g_globalCursor;

static wxCursor  gs_savedCursor;
static int       gs_busyCount = 0;

const wxCursor &wxBusyCursor::GetStoredCursor()
{
    return gs_savedCursor;
}

const wxCursor wxBusyCursor::GetBusyCursor()
{
    return wxCursor(wxCURSOR_WATCH);
}

static void UpdateCursors(const wxWindowList& list, GdkDisplay*& display)
{
    wxWindowList::const_iterator i = list.begin();
    for (size_t n = list.size(); n--; ++i)
    {
        wxWindow* win = *i;
        if (display == NULL && win->m_widget && win->m_widget->window)
            display = gdk_drawable_get_display(win->m_widget->window);
        win->GTKUpdateCursor(true, false);
        UpdateCursors(win->GetChildren(), display);
    }
}

void wxEndBusyCursor()
{
    if (--gs_busyCount > 0)
        return;

    g_globalCursor = gs_savedCursor;
    gs_savedCursor = wxNullCursor;
    GdkDisplay* unused = NULL;
    UpdateCursors(wxTopLevelWindows, unused);
}

void wxBeginBusyCursor(const wxCursor* cursor)
{
    if (gs_busyCount++ > 0)
        return;

    wxASSERT_MSG( !gs_savedCursor.Ok(),
                  wxT("forgot to call wxEndBusyCursor, will leak memory") );

    gs_savedCursor = g_globalCursor;
    g_globalCursor = *cursor;
    GdkDisplay* display = NULL;
    UpdateCursors(wxTopLevelWindows, display);
    if (display)
        gdk_display_flush(display);
}

bool wxIsBusy()
{
    return gs_busyCount > 0;
}

void wxSetCursor( const wxCursor& cursor )
{
    g_globalCursor = cursor;
    GdkDisplay* unused = NULL;
    UpdateCursors(wxTopLevelWindows, unused);
}
