/* A Gtk Widget that inherits GtkFixed, but can be shrunk.
This file is only use when compiling with Gtk+ 3.

Copyright (C) 2011-2020 Free Software Foundation, Inc.

This file is part of GNU Emacs.

GNU Emacs 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.

GNU Emacs 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 GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

#include "lisp.h"
#include "frame.h"
#include "xterm.h"
#include "xwidget.h"
#include "emacsgtkfixed.h"

/* Silence a bogus diagnostic; see GNOME bug 683906.  */
#if GNUC_PREREQ (4, 7, 0) && ! GLIB_CHECK_VERSION (2, 35, 7)
# pragma GCC diagnostic push
# pragma GCC diagnostic ignored "-Wunused-local-typedefs"
#endif

typedef struct _EmacsFixed EmacsFixed;
typedef struct _EmacsFixedClass EmacsFixedClass;

struct _EmacsFixedPrivate
{
  struct frame *f;
};


static void emacs_fixed_get_preferred_width  (GtkWidget *widget,
                                              gint      *minimum,
                                              gint      *natural);
static void emacs_fixed_get_preferred_height (GtkWidget *widget,
                                              gint      *minimum,
                                              gint      *natural);
static GType emacs_fixed_get_type (void);
G_DEFINE_TYPE (EmacsFixed, emacs_fixed, GTK_TYPE_FIXED)

static EmacsFixed *
EMACS_FIXED (GtkWidget *widget)
{
  return G_TYPE_CHECK_INSTANCE_CAST (widget, emacs_fixed_get_type (),
				     EmacsFixed);
}

#ifdef HAVE_XWIDGETS

static EmacsFixedClass *
EMACS_FIXED_GET_CLASS (GtkWidget *widget)
{
  return G_TYPE_INSTANCE_GET_CLASS (widget, emacs_fixed_get_type (),
				    EmacsFixedClass);
}

struct GtkFixedPrivateL
{
  GList *children;
};

static void
emacs_fixed_gtk_widget_size_allocate (GtkWidget *widget,
				      GtkAllocation *allocation)
{
  /* For xwidgets.

     This basically re-implements the base class method and adds an
     additional case for an xwidget view.

     It would be nicer if the bse class method could be called first,
     and the xview modification only would remain here. It wasn't
     possible to solve it that way yet.  */
  EmacsFixedClass *klass;
  GtkWidgetClass *parent_class;
  struct GtkFixedPrivateL *priv;

  klass = EMACS_FIXED_GET_CLASS (widget);
  parent_class = g_type_class_peek_parent (klass);
  parent_class->size_allocate (widget, allocation);

  priv = G_TYPE_INSTANCE_GET_PRIVATE (widget, GTK_TYPE_FIXED,
				      struct GtkFixedPrivateL);

  gtk_widget_set_allocation (widget, allocation);

  if (gtk_widget_get_has_window (widget))
    {
      if (gtk_widget_get_realized (widget))
        gdk_window_move_resize (gtk_widget_get_window (widget),
                                allocation->x,
                                allocation->y,
                                allocation->width,
                                allocation->height);
    }

  for (GList *children = priv->children; children; children = children->next)
    {
      GtkFixedChild *child = children->data;

      if (!gtk_widget_get_visible (child->widget))
        continue;

      GtkRequisition child_requisition;
      gtk_widget_get_preferred_size (child->widget, &child_requisition, NULL);

      GtkAllocation child_allocation;
      child_allocation.x = child->x;
      child_allocation.y = child->y;

      if (!gtk_widget_get_has_window (widget))
        {
          child_allocation.x += allocation->x;
          child_allocation.y += allocation->y;
        }

      child_allocation.width = child_requisition.width;
      child_allocation.height = child_requisition.height;

      struct xwidget_view *xv
        = g_object_get_data (G_OBJECT (child->widget), XG_XWIDGET_VIEW);
      if (xv)
        {
          child_allocation.width = xv->clip_right;
          child_allocation.height = xv->clip_bottom - xv->clip_top;
        }

      gtk_widget_size_allocate (child->widget, &child_allocation);
    }
}

#endif  /* HAVE_XWIDGETS */

static void
emacs_fixed_class_init (EmacsFixedClass *klass)
{
  GtkWidgetClass *widget_class;

  widget_class = (GtkWidgetClass *) klass;

  widget_class->get_preferred_width = emacs_fixed_get_preferred_width;
  widget_class->get_preferred_height = emacs_fixed_get_preferred_height;
#ifdef HAVE_XWIDGETS
  widget_class->size_allocate = emacs_fixed_gtk_widget_size_allocate;
#endif
  g_type_class_add_private (klass, sizeof (EmacsFixedPrivate));
}

static void
emacs_fixed_init (EmacsFixed *fixed)
{
  fixed->priv = G_TYPE_INSTANCE_GET_PRIVATE (fixed, emacs_fixed_get_type (),
                                             EmacsFixedPrivate);
  fixed->priv->f = 0;
}

GtkWidget *
emacs_fixed_new (struct frame *f)
{
  EmacsFixed *fixed = g_object_new (emacs_fixed_get_type (), NULL);
  EmacsFixedPrivate *priv = fixed->priv;
  priv->f = f;
  return GTK_WIDGET (fixed);
}

static void
emacs_fixed_get_preferred_width (GtkWidget *widget,
                                 gint      *minimum,
                                 gint      *natural)
{
  EmacsFixed *fixed = EMACS_FIXED (widget);
  EmacsFixedPrivate *priv = fixed->priv;
  int w = priv->f->output_data.x->size_hints.min_width;
  if (minimum) *minimum = w;
  if (natural) *natural = w;
}

static void
emacs_fixed_get_preferred_height (GtkWidget *widget,
                                  gint      *minimum,
                                  gint      *natural)
{
  EmacsFixed *fixed = EMACS_FIXED (widget);
  EmacsFixedPrivate *priv = fixed->priv;
  int h = priv->f->output_data.x->size_hints.min_height;
  if (minimum) *minimum = h;
  if (natural) *natural = h;
}


/* Override the X function so we can intercept Gtk+ 3 calls.
   Use our values for min_width/height so that KDE don't freak out
   (Bug#8919), and so users can resize our frames as they wish.  */

void
XSetWMSizeHints (Display *d,
                 Window w,
                 XSizeHints *hints,
                 Atom prop)
{
  struct x_display_info *dpyinfo = x_display_info_for_display (d);
  struct frame *f = x_top_window_to_frame (dpyinfo, w);
  long data[18];
  data[0] = hints->flags;
  data[1] = hints->x;
  data[2] = hints->y;
  data[3] = hints->width;
  data[4] = hints->height;
  data[5] = hints->min_width;
  data[6] = hints->min_height;
  data[7] = hints->max_width;
  data[8] = hints->max_height;
  data[9] = hints->width_inc;
  data[10] = hints->height_inc;
  data[11] = hints->min_aspect.x;
  data[12] = hints->min_aspect.y;
  data[13] = hints->max_aspect.x;
  data[14] = hints->max_aspect.y;
  data[15] = hints->base_width;
  data[16] = hints->base_height;
  data[17] = hints->win_gravity;

  if ((hints->flags & PMinSize) && f)
    {
      int w = f->output_data.x->size_hints.min_width;
      int h = f->output_data.x->size_hints.min_height;
      data[5] = w;
      data[6] = h;
    }

  XChangeProperty (d, w, prop, XA_WM_SIZE_HINTS, 32, PropModeReplace,
		   (unsigned char *) data, 18);
}

/* Override this X11 function.
   This function is in the same X11 file as the one above.  So we must
   provide it also.  */

void
XSetWMNormalHints (Display *d, Window w, XSizeHints *hints)
{
  XSetWMSizeHints (d, w, hints, XA_WM_NORMAL_HINTS);
}