/*

 * Copyright © 2019  Ebrahim Byagowi

 *

 *  This is part of HarfBuzz, a text shaping library.

 *

 * Permission is hereby granted, without written agreement and without

 * license or royalty fees, to use, copy, modify, and distribute this

 * software and its documentation for any purpose, provided that the

 * above copyright notice and the following two paragraphs appear in

 * all copies of this software.

 *

 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR

 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES

 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN

 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH

 * DAMAGE.

 *

 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,

 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND

 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS

 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO

 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

 */

#ifndef HB_AAT_LAYOUT_OPBD_TABLE_HH

#define HB_AAT_LAYOUT_OPBD_TABLE_HH

#include "hb-aat-layout-common.hh"

#include "hb-open-type.hh"

/*

 * opbd -- Optical Bounds

 * https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6opbd.html

 */

#define HB_AAT_TAG_opbd HB_TAG('o','p','b','d')

namespace AAT {

struct OpticalBounds

{

  bool sanitize (hb_sanitize_context_t *c) const

  {

    TRACE_SANITIZE (this);

    return_trace (c->check_struct (this));

  }

  FWORD   leftSide;

  FWORD   topSide;

  FWORD   rightSide;

  FWORD   bottomSide;

  public:

  DEFINE_SIZE_STATIC (8);

};

struct opbdFormat0

{

  bool get_bounds (hb_font_t *font, hb_codepoint_t glyph_id,

       hb_glyph_extents_t *extents, const void *base) const

  {

    const Offset16To<OpticalBounds> *bounds_offset = lookupTable.get_value (glyph_id, font->face->get_num_glyphs ());

    if (!bounds_offset) return false;

    const OpticalBounds &bounds = base+*bounds_offset;

    if (extents)

      *extents = {

  font->em_scale_x (bounds.leftSide),

  font->em_scale_y (bounds.topSide),

  font->em_scale_x (bounds.rightSide),

  font->em_scale_y (bounds.bottomSide)

      };

    return true;

  }

  bool sanitize (hb_sanitize_context_t *c, const void *base) const

  {

    TRACE_SANITIZE (this);

    return_trace (likely (c->check_struct (this) && lookupTable.sanitize (c, base)));

  }

  protected:

  Lookup<Offset16To<OpticalBounds>>

    lookupTable;  /* Lookup table associating glyphs with the four

         * int16 values for the left-side, top-side,

         * right-side, and bottom-side optical bounds. */

  public:

  DEFINE_SIZE_MIN (2);

};

struct opbdFormat1

{

  bool get_bounds (hb_font_t *font, hb_codepoint_t glyph_id,

       hb_glyph_extents_t *extents, const void *base) const

  {

    const Offset16To<OpticalBounds> *bounds_offset = lookupTable.get_value (glyph_id, font->face->get_num_glyphs ());

    if (!bounds_offset) return false;

    const OpticalBounds &bounds = base+*bounds_offset;

    hb_position_t left = 0, top = 0, right = 0, bottom = 0, ignore;

    if (font->get_glyph_contour_point (glyph_id, bounds.leftSide, &left, &ignore) ||

  font->get_glyph_contour_point (glyph_id, bounds.topSide, &ignore, &top) ||

  font->get_glyph_contour_point (glyph_id, bounds.rightSide, &right, &ignore) ||

  font->get_glyph_contour_point (glyph_id, bounds.bottomSide, &ignore, &bottom))

    {

      if (extents)

  *extents = {left, top, right, bottom};

      return true;

    }

    return false;

  }

  bool sanitize (hb_sanitize_context_t *c, const void *base) const

  {

    TRACE_SANITIZE (this);

    return_trace (likely (c->check_struct (this) && lookupTable.sanitize (c, base)));

  }

  protected:

  Lookup<Offset16To<OpticalBounds>>

    lookupTable;  /* Lookup table associating glyphs with the four

         * int16 values for the left-side, top-side,

         * right-side, and bottom-side optical bounds. */

  public:

  DEFINE_SIZE_MIN (2);

};

struct opbd

{

  static constexpr hb_tag_t tableTag = HB_AAT_TAG_opbd;

  bool get_bounds (hb_font_t *font, hb_codepoint_t glyph_id,

       hb_glyph_extents_t *extents) const

  {

    switch (format)

    {

    case 0: hb_barrier (); return u.format0.get_bounds (font, glyph_id, extents, this);

    case 1: hb_barrier (); return u.format1.get_bounds (font, glyph_id, extents, this);

    default:return false;

    }

  }

  bool sanitize (hb_sanitize_context_t *c) const

  {

    TRACE_SANITIZE (this);

    if (unlikely (!c->check_struct (this) || version.major != 1))

      return_trace (false);

    hb_barrier ();

    switch (format)

    {

    case 0: hb_barrier (); return_trace (u.format0.sanitize (c, this));

    case 1: hb_barrier (); return_trace (u.format1.sanitize (c, this));

    default:return_trace (true);

    }

  }

  protected:

  FixedVersion<>version;  /* Version number of the optical bounds

         * table (0x00010000 for the current version). */

  HBUINT16  format;   /* Format of the optical bounds table.

         * Format 0 indicates distance and Format 1 indicates

         * control point. */

  union {

  opbdFormat0 format0;

  opbdFormat1 format1;

  } u;

  public:

  DEFINE_SIZE_MIN (8);

};

} /* namespace AAT */

#endif /* HB_AAT_LAYOUT_OPBD_TABLE_HH */