/*

 * Copyright © 2016  Igalia S.L.

 *

 *  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.

 *

 * Igalia Author(s): Frédéric Wang

 */

#include "hb-open-type-private.hh"

#include "hb-ot-layout-private.hh"

#include "hb-ot-math-table.hh"

static inline const OT::MATH&

_get_math (hb_face_t *face)

{

  if (unlikely (!hb_ot_shaper_face_data_ensure (face))) return OT::Null(OT::MATH);

  hb_ot_layout_t * layout = hb_ot_layout_from_face (face);

  return *(layout->math.get ());

}

/*

 * OT::MATH

 */

/**

 * hb_ot_math_has_data:

 * @face: #hb_face_t to test

 *

 * This function allows to verify the presence of an OpenType MATH table on the

 * face.

 *

 * Return value: true if face has a MATH table, false otherwise

 *

 * Since: 1.3.3

 **/

hb_bool_t

hb_ot_math_has_data (hb_face_t *face)

{

  return &_get_math (face) != &OT::Null(OT::MATH);

}

/**

 * hb_ot_math_get_constant:

 * @font: #hb_font_t from which to retrieve the value

 * @constant: #hb_ot_math_constant_t the constant to retrieve

 *

 * This function returns the requested math constants as a #hb_position_t.

 * If the request constant is HB_OT_MATH_CONSTANT_SCRIPT_PERCENT_SCALE_DOWN,

 * HB_OT_MATH_CONSTANT_SCRIPT_SCRIPT_PERCENT_SCALE_DOWN or

 * HB_OT_MATH_CONSTANT_SCRIPT_PERCENT_SCALE_DOWN then the return value is

 * actually an integer between 0 and 100 representing that percentage.

 *

 * Return value: the requested constant or 0

 *

 * Since: 1.3.3

 **/

hb_position_t

hb_ot_math_get_constant (hb_font_t *font,

			 hb_ot_math_constant_t constant)

{

  const OT::MATH &math = _get_math (font->face);

  return math.get_constant(constant, font);

}

/**

 * hb_ot_math_get_glyph_italics_correction:

 * @font: #hb_font_t from which to retrieve the value

 * @glyph: glyph index from which to retrieve the value

 *

 * Return value: the italics correction of the glyph or 0

 *

 * Since: 1.3.3

 **/

hb_position_t

hb_ot_math_get_glyph_italics_correction (hb_font_t *font,

					 hb_codepoint_t glyph)

{

  const OT::MATH &math = _get_math (font->face);

  return math.get_math_glyph_info().get_italics_correction (glyph, font);

}

/**

 * hb_ot_math_get_glyph_top_accent_attachment:

 * @font: #hb_font_t from which to retrieve the value

 * @glyph: glyph index from which to retrieve the value

 *

 * Return value: the top accent attachment of the glyph or 0

 *

 * Since: 1.3.3

 **/

hb_position_t

hb_ot_math_get_glyph_top_accent_attachment (hb_font_t *font,

					    hb_codepoint_t glyph)

{

  const OT::MATH &math = _get_math (font->face);

  return math.get_math_glyph_info().get_top_accent_attachment (glyph, font);

}

/**

 * hb_ot_math_is_glyph_extended_shape:

 * @face: a #hb_face_t to test

 * @glyph: a glyph index to test

 *

 * Return value: true if the glyph is an extended shape, false otherwise

 *

 * Since: 1.3.3

 **/

hb_bool_t

hb_ot_math_is_glyph_extended_shape (hb_face_t *face,

				    hb_codepoint_t glyph)

{

  const OT::MATH &math = _get_math (face);

  return math.get_math_glyph_info().is_extended_shape (glyph);

}

/**

 * hb_ot_math_get_glyph_kerning:

 * @font: #hb_font_t from which to retrieve the value

 * @glyph: glyph index from which to retrieve the value

 * @kern: the #hb_ot_math_kern_t from which to retrieve the value

 * @correction_height: the correction height to use to determine the kerning.

 *

 * This function tries to retrieve the MathKern table for the specified font,

 * glyph and #hb_ot_math_kern_t. Then it browses the list of heights from the

 * MathKern table to find one value that is greater or equal to specified

 * correction_height. If one is found the corresponding value from the list of

 * kerns is returned and otherwise the last kern value is returned.

 *

 * Return value: requested kerning or 0

 *

 * Since: 1.3.3

 **/

hb_position_t

hb_ot_math_get_glyph_kerning (hb_font_t *font,

			      hb_codepoint_t glyph,

			      hb_ot_math_kern_t kern,

			      hb_position_t correction_height)

{

  const OT::MATH &math = _get_math (font->face);

  return math.get_math_glyph_info().get_kerning (glyph, kern, correction_height, font);

}

/**

 * hb_ot_math_get_glyph_variants:

 * @font: #hb_font_t from which to retrieve the values

 * @glyph: index of the glyph to stretch

 * @direction: direction of the stretching

 * @start_offset: offset of the first variant to retrieve

 * @variants_count: maximum number of variants to retrieve after start_offset

 * (IN) and actual number of variants retrieved (OUT)

 * @variants: array of size at least @variants_count to store the result

 *

 * This function tries to retrieve the MathGlyphConstruction for the specified

 * font, glyph and direction. Note that only the value of

 * #HB_DIRECTION_IS_HORIZONTAL is considered. It provides the corresponding list

 * of size variants as an array of hb_ot_math_glyph_variant_t structs.

 *

 * Return value: the total number of size variants available or 0

 *

 * Since: 1.3.3

 **/

unsigned int

hb_ot_math_get_glyph_variants (hb_font_t *font,

			       hb_codepoint_t glyph,

			       hb_direction_t direction,

			       unsigned int start_offset,

			       unsigned int *variants_count, /* IN/OUT */

			       hb_ot_math_glyph_variant_t *variants /* OUT */)

{

  const OT::MATH &math = _get_math (font->face);

  return math.get_math_variants().get_glyph_variants (glyph, direction, font,

						      start_offset,

						      variants_count,

						      variants);

}

/**

 * hb_ot_math_get_min_connector_overlap:

 * @font: #hb_font_t from which to retrieve the value

 * @direction: direction of the stretching

 *

 * This function tries to retrieve the MathVariants table for the specified

 * font and returns the minimum overlap of connecting glyphs to draw a glyph

 * assembly in the specified direction. Note that only the value of

 * #HB_DIRECTION_IS_HORIZONTAL is considered.

 *

 * Return value: requested min connector overlap or 0

 *

 * Since: 1.3.3

 **/

hb_position_t

hb_ot_math_get_min_connector_overlap (hb_font_t *font,

				      hb_direction_t direction)

{

  const OT::MATH &math = _get_math (font->face);

  return math.get_math_variants().get_min_connector_overlap (direction, font);

}

/**

 * hb_ot_math_get_glyph_assembly:

 * @font: #hb_font_t from which to retrieve the values

 * @glyph: index of the glyph to stretch

 * @direction: direction of the stretching

 * @start_offset: offset of the first glyph part to retrieve

 * @parts_count: maximum number of glyph parts to retrieve after start_offset

 * (IN) and actual number of parts retrieved (OUT)

 * @parts: array of size at least @parts_count to store the result

 * @italics_correction: italic correction of the glyph assembly

 *

 * This function tries to retrieve the GlyphAssembly for the specified font,

 * glyph and direction. Note that only the value of #HB_DIRECTION_IS_HORIZONTAL

 * is considered. It provides the information necessary to draw the glyph

 * assembly as an array of #hb_ot_math_glyph_part_t.

 *

 * Return value: the total number of parts in the glyph assembly

 *

 * Since: 1.3.3

 **/

unsigned int

hb_ot_math_get_glyph_assembly (hb_font_t *font,

			       hb_codepoint_t glyph,

			       hb_direction_t direction,

			       unsigned int start_offset,

			       unsigned int *parts_count, /* IN/OUT */

			       hb_ot_math_glyph_part_t *parts, /* OUT */

			       hb_position_t *italics_correction /* OUT */)

{

  const OT::MATH &math = _get_math (font->face);

  return math.get_math_variants().get_glyph_parts (glyph, direction, font,

						   start_offset,

						   parts_count,

						   parts,

						   italics_correction);

}