/* GTK - The GIMP Toolkit
 * Copyright (C) 2011 Benjamin Otte <otte@gnome.org>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library. If not, see <http://www.gnu.org/licenses/>.
 */

#include "config.h"

#include "gtkcsstypesprivate.h"

#include "gtkcssnumbervalueprivate.h"
#include "gtkstylecontextprivate.h"

#define DEFINE_BOXED_TYPE_WITH_COPY_FUNC(TypeName, type_name) \
\
static TypeName * \
type_name ## _copy (const TypeName *foo) \
{ \
  return g_memdup (foo, sizeof (TypeName)); \
} \
\
G_DEFINE_BOXED_TYPE (TypeName, type_name, type_name ## _copy, g_free)

DEFINE_BOXED_TYPE_WITH_COPY_FUNC (GtkCssBackgroundSize, _gtk_css_background_size)
DEFINE_BOXED_TYPE_WITH_COPY_FUNC (GtkCssBorderImageRepeat, _gtk_css_border_image_repeat)

typedef struct _GtkCssChangeTranslation GtkCssChangeTranslation;
struct _GtkCssChangeTranslation {
  GtkCssChange from;
  GtkCssChange to;
};

static GtkCssChange
gtk_css_change_translate (GtkCssChange                   match,
                         const GtkCssChangeTranslation *translations,
                         guint                         n_translations)
{
  GtkCssChange result = match;
  guint i;

  for (i = 0; i < n_translations; i++)
    {
      if (match & translations[i].from)
        {
          result &= ~translations[i].from;
          result |= translations[i].to;
        }
    }

  return result;
}

GtkCssChange
_gtk_css_change_for_sibling (GtkCssChange match)
{
  static const GtkCssChangeTranslation table[] = {
    { GTK_CSS_CHANGE_CLASS, GTK_CSS_CHANGE_SIBLING_CLASS },
    { GTK_CSS_CHANGE_NAME, GTK_CSS_CHANGE_SIBLING_NAME },
    { GTK_CSS_CHANGE_POSITION, GTK_CSS_CHANGE_SIBLING_POSITION },
    { GTK_CSS_CHANGE_STATE, GTK_CSS_CHANGE_SIBLING_STATE },
  };

  return gtk_css_change_translate (match, table, G_N_ELEMENTS (table)); 
}

GtkCssChange
_gtk_css_change_for_child (GtkCssChange match)
{
  static const GtkCssChangeTranslation table[] = {
    { GTK_CSS_CHANGE_CLASS, GTK_CSS_CHANGE_PARENT_CLASS },
    { GTK_CSS_CHANGE_NAME, GTK_CSS_CHANGE_PARENT_NAME },
    { GTK_CSS_CHANGE_POSITION, GTK_CSS_CHANGE_PARENT_POSITION },
    { GTK_CSS_CHANGE_STATE, GTK_CSS_CHANGE_PARENT_STATE },
    { GTK_CSS_CHANGE_SIBLING_CLASS, GTK_CSS_CHANGE_PARENT_SIBLING_CLASS },
    { GTK_CSS_CHANGE_SIBLING_NAME, GTK_CSS_CHANGE_PARENT_SIBLING_NAME },
    { GTK_CSS_CHANGE_SIBLING_POSITION, GTK_CSS_CHANGE_PARENT_SIBLING_POSITION },
    { GTK_CSS_CHANGE_SIBLING_STATE, GTK_CSS_CHANGE_PARENT_SIBLING_STATE }
  };

  return gtk_css_change_translate (match, table, G_N_ELEMENTS (table)); 
}

void
_gtk_css_number_init (GtkCssNumber *number,
                      double        value,
                      GtkCssUnit    unit)
{
  number->value = value;
  number->unit = unit;
}

gboolean
_gtk_css_number_equal (const GtkCssNumber *one,
                       const GtkCssNumber *two)
{
  return one->unit == two->unit &&
         one->value == two->value;
}

double
_gtk_css_number_get (const GtkCssNumber *number,
                     double              one_hundred_percent)
{
  if (number->unit == GTK_CSS_PERCENT)
    return number->value * one_hundred_percent * 0.01;
  else
    return number->value;
}

gboolean
_gtk_css_number_compute (GtkCssNumber       *dest,
                         const GtkCssNumber *src,
                         GtkStyleContext    *context)
{
  switch (src->unit)
    {
    default:
      g_assert_not_reached();
      /* fall through */
    case GTK_CSS_PERCENT:
    case GTK_CSS_NUMBER:
    case GTK_CSS_PX:
    case GTK_CSS_DEG:
      dest->value = src->value;
      dest->unit = src->unit;
      break;
    case GTK_CSS_PT:
      dest->value = src->value * 96.0 / 72.0;
      dest->unit = GTK_CSS_PX;
      break;
    case GTK_CSS_PC:
      dest->value = src->value * 96.0 / 72.0 * 12.0;
      dest->unit = GTK_CSS_PX;
      break;
    case GTK_CSS_IN:
      dest->value = src->value * 96.0;
      dest->unit = GTK_CSS_PX;
      break;
    case GTK_CSS_CM:
      dest->value = src->value * 96.0 * 0.39370078740157477;
      dest->unit = GTK_CSS_PX;
      break;
    case GTK_CSS_MM:
      dest->value = src->value * 96.0 * 0.039370078740157477;
      dest->unit = GTK_CSS_PX;
      break;
    case GTK_CSS_EM:
      dest->value = src->value * _gtk_css_number_value_get (_gtk_style_context_peek_property (context, GTK_CSS_PROPERTY_FONT_SIZE), 100);
      dest->unit = GTK_CSS_PX;
      break;
    case GTK_CSS_EX:
      /* for now we pretend ex is half of em */
      dest->value = src->value * _gtk_css_number_value_get (_gtk_style_context_peek_property (context, GTK_CSS_PROPERTY_FONT_SIZE), 100);
      dest->unit = GTK_CSS_PX;
      break;
    case GTK_CSS_RAD:
      dest->value = 360 * src->value / (2 * G_PI);
      dest->unit = GTK_CSS_DEG;
      break;
    case GTK_CSS_GRAD:
      dest->value = 360 * src->value / 400.0;
      dest->unit = GTK_CSS_DEG;
      break;
    case GTK_CSS_TURN:
      dest->value = 360 * src->value;
      dest->unit = GTK_CSS_DEG;
      break;
    }

  return !_gtk_css_number_equal (src, dest);
}

void
_gtk_css_number_print (const GtkCssNumber *number,
                       GString            *string)
{
  char buf[G_ASCII_DTOSTR_BUF_SIZE];

  const char *names[] = {
    /* [GTK_CSS_NUMBER] = */ "",
    /* [GTK_CSS_PERCENT] = */ "%",
    /* [GTK_CSS_PX] = */ "px",
    /* [GTK_CSS_PT] = */ "pt",
    /* [GTK_CSS_EM] = */ "em",
    /* [GTK_CSS_EX] = */ "ex",
    /* [GTK_CSS_PC] = */ "pc",
    /* [GTK_CSS_IN] = */ "in",
    /* [GTK_CSS_CM] = */ "cm",
    /* [GTK_CSS_MM] = */ "mm",
    /* [GTK_CSS_RAD] = */ "rad",
    /* [GTK_CSS_DEG] = */ "deg",
    /* [GTK_CSS_GRAD] = */ "grad",
    /* [GTK_CSS_TURN] = */ "turn",
  };

  g_return_if_fail (number != NULL);
  g_return_if_fail (string != NULL);

  g_ascii_dtostr (buf, sizeof (buf), number->value);
  g_string_append (string, buf);
  if (number->value != 0.0)
    g_string_append (string, names[number->unit]);
}