/** typednd.c **/
#include <gnome.h>

#include "minilogo.xpm"

#define HEIGHT 300
#define WIDTH 200

#define TARGET_TYPE_TEXT 80
#define TARGET_TYPE_PIXMAP 81

typedef struct {
    GtkWidget *app;
    GnomeCanvasGroup *rootGroup;
} tdContext;

static GtkTargetEntry fromImage[] = {
    { "text/plain", 0, TARGET_TYPE_TEXT },
    { "image/x-xpixmap", 0, TARGET_TYPE_PIXMAP }
};
static GtkTargetEntry toButton =
    { "text/plain", 0, TARGET_TYPE_TEXT };
static GtkTargetEntry toCanvas =
    { "image/x-xpixmap", 0, TARGET_TYPE_PIXMAP };

gint eventDelete(GtkWidget *widget,
        GdkEvent *event,gpointer data);
gint eventDestroy(GtkWidget *widget,
        GdkEvent *event,gpointer data);
GtkWidget *makeLayout(tdContext *tdcontext);
void addImage(tdContext *tdcontext,char **xpm,
        gint x,gint y);
void sendCallback(GtkWidget *widget,
        GdkDragContext *context,
        GtkSelectionData *selection,guint info,guint time);
void receiveCallback(GtkWidget *widget,
        GdkDragContext *context,
        gint x,gint y,GtkSelectionData *selection,
        guint info,guint time,tdContext *tdcontext);

int main(int argc,char *argv[])
{
    GtkWidget *layout;
    tdContext *tdcontext = g_malloc0(sizeof(tdContext));

    gnome_init("typednd","1.0",argc,argv);
    tdcontext->app = gnome_app_new("typednd","Type DND");
    gtk_signal_connect(GTK_OBJECT(tdcontext->app),
            "delete_event",
            GTK_SIGNAL_FUNC(eventDelete),NULL);
    gtk_signal_connect(GTK_OBJECT(tdcontext->app),
            "destroy",
            GTK_SIGNAL_FUNC(eventDestroy), NULL);
    gtk_widget_show_all(tdcontext->app);

    layout = makeLayout(tdcontext);
    gnome_app_set_contents(GNOME_APP(tdcontext->app),
            layout);

    gtk_widget_show_all(tdcontext->app);
    gtk_main();
    exit(0);
}
GtkWidget *makeLayout(tdContext *tdcontext)
{
    GtkWidget *box;
    GtkWidget *canvas;
    GtkWidget *button;

    box = gtk_vbox_new(FALSE,0);
    gtk_widget_show(box);

    canvas = gnome_canvas_new();
    gtk_widget_set_usize(canvas,WIDTH,HEIGHT);
    gnome_canvas_set_scroll_region(GNOME_CANVAS(canvas),
            0.0,0.0,WIDTH,HEIGHT);
    tdcontext->rootGroup =
            gnome_canvas_root(GNOME_CANVAS(canvas));

    gtk_signal_connect(GTK_OBJECT(canvas),
            "drag_data_received",
            GTK_SIGNAL_FUNC(receiveCallback),tdcontext);
    gtk_drag_dest_set(canvas,
            GTK_DEST_DEFAULT_MOTION |
            GTK_DEST_DEFAULT_HIGHLIGHT |
            GTK_DEST_DEFAULT_DROP,
            &toCanvas,1,
            GDK_ACTION_COPY);

    gtk_box_pack_start(GTK_BOX(box),canvas,TRUE,FALSE,0);

    addImage(tdcontext,minilogo,WIDTH/2,HEIGHT/2);

    button = gtk_button_new_with_label("Text Target");
    gtk_signal_connect(GTK_OBJECT(button),
            "drag_data_received",
            GTK_SIGNAL_FUNC(receiveCallback),tdcontext);
    gtk_drag_dest_set(button,
            GTK_DEST_DEFAULT_MOTION |
            GTK_DEST_DEFAULT_HIGHLIGHT |
            GTK_DEST_DEFAULT_DROP,
            &toButton,1,
            GDK_ACTION_COPY);
    gtk_box_pack_start(GTK_BOX(box),button,TRUE,FALSE,0);

    return(box);
}
void addImage(tdContext *tdcontext,char **xpm,
        gint x,gint y)
{
    int width;
    int height;
    GtkStyle *style;
    GdkBitmap *mask;
    GdkPixmap *pixmap;
    GtkWidget *button;
    GtkWidget *pixmapWidget;
    GnomeCanvasItem *item;

    style = gtk_widget_get_style(
            GTK_WIDGET(tdcontext->app));
    pixmap = gdk_pixmap_create_from_xpm_d(
            GTK_WIDGET(tdcontext->app)->window,
            &mask,&style->bg[GTK_STATE_NORMAL],xpm);
    pixmapWidget = gtk_pixmap_new(pixmap,mask);
    button = gtk_button_new();
    gtk_container_add(GTK_CONTAINER(button),pixmapWidget);

    sscanf(xpm[0],"%d %d",&width,&height);
    item = gnome_canvas_item_new(tdcontext->rootGroup,
                    gnome_canvas_widget_get_type(),
                    "widget",button,
                    "x",(double)x,
                    "y",(double)y,
                    "width",(double)width + 10,
                    "height",(double)height + 10,
                    "anchor",GTK_ANCHOR_CENTER,
                    NULL);
    gtk_signal_connect(GTK_OBJECT(button),"drag_data_get",
            GTK_SIGNAL_FUNC(sendCallback),NULL);
    gtk_drag_source_set(GTK_WIDGET(button),
            GDK_BUTTON1_MASK,
            fromImage,2,
            GDK_ACTION_COPY);
    gtk_widget_show_all(button);
}
void sendCallback(GtkWidget *widget,
        GdkDragContext *context,
        GtkSelectionData *selection,guint targetType,
        guint eventTime)
{
    char str[80];
    time_t now;

    switch(targetType) {
    case TARGET_TYPE_TEXT:
        time(&now);
        strcpy(str,ctime(&now));
        str[24] = '\0';
        gtk_selection_data_set(selection,
            selection->target,8,
            (guchar *)str,strlen(str));
        break;
    case TARGET_TYPE_PIXMAP:
        gtk_selection_data_set(selection,
            selection->target,8,
            (guchar *)minilogo,sizeof(minilogo));
        break;
    default:
        break;
    }
}
void receiveCallback(GtkWidget *widget,
        GdkDragContext *context,
        gint x,gint y,GtkSelectionData *selection,
        guint targetType,guint time,tdContext *tdcontext)
{
    GtkWidget *label;

    switch(targetType) {
    case TARGET_TYPE_TEXT:
        label = GTK_BUTTON(widget)->child;
        gtk_label_set_text(GTK_LABEL(label),
                selection->data);
        break;
    case TARGET_TYPE_PIXMAP:
        addImage(tdcontext,(gchar **)selection->data,x,y);
        break;
    default:
        break;
    }
}
gint eventDelete(GtkWidget *widget,
        GdkEvent *event,gpointer data) {
    return(FALSE);
}
gint eventDestroy(GtkWidget *widget,
        GdkEvent *event,gpointer data) {
    gtk_main_quit();
    return(0);
}