/*

 * 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.hh"

#ifndef HB_NO_MATH

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

/**

 * SECTION:hb-ot-math

 * @title: hb-ot-math

 * @short_description: OpenType Math information

 * @include: hb-ot.h

 *

 * Functions for fetching mathematics layout data from OpenType fonts.

 *

 * HarfBuzz itself does not implement a math layout solution. The

 * functions and types provided can be used by client programs to access

 * the font data necessary for typesetting OpenType Math layout.

 *

 **/

/*

 * OT::MATH

 */

/**

 * hb_ot_math_has_data:

 * @face: #hb_face_t to test

 *

 * Tests whether a face has a `MATH` table.

 *

 * Return value: `true` if the table is found, `false` otherwise

 *

 * Since: 1.3.3

 **/

hb_bool_t

hb_ot_math_has_data (hb_face_t *face)

{

  return face->table.MATH->has_data ();

}

/**

 * hb_ot_math_get_constant:

 * @font: #hb_font_t to work upon

 * @constant: #hb_ot_math_constant_t the constant to retrieve

 *

 * Fetches the specified math constant. For most constants, the value returned

 * is an #hb_position_t.

 *

 * However, if the requested 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

 * an integer between 0 and 100 representing that percentage.

 *

 * Return value: the requested constant or zero

 *

 * Since: 1.3.3

 **/

hb_position_t

hb_ot_math_get_constant (hb_font_t *font,

       hb_ot_math_constant_t constant)

{

  return font->face->table.MATH->get_constant(constant, font);

}

/**

 * hb_ot_math_get_glyph_italics_correction:

 * @font: #hb_font_t to work upon

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

 *

 * Fetches an italics-correction value (if one exists) for the specified

 * glyph index.

 *

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

 *

 * Since: 1.3.3

 **/

hb_position_t

hb_ot_math_get_glyph_italics_correction (hb_font_t *font,

           hb_codepoint_t glyph)

{

  return font->face->table.MATH->get_glyph_info().get_italics_correction (glyph, font);

}

/**

 * hb_ot_math_get_glyph_top_accent_attachment:

 * @font: #hb_font_t to work upon

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

 *

 * Fetches a top-accent-attachment value (if one exists) for the specified

 * glyph index.

 *

 * For any glyph that does not have a top-accent-attachment value - that is,

 * a glyph not covered by the `MathTopAccentAttachment` table (or, when

 * @font has no `MathTopAccentAttachment` table or no `MATH` table, any

 * glyph) - the function synthesizes a value, returning the position at

 * one-half the glyph's advance width.

 *

 * Return value: the top accent attachment of the glyph or 0.5 * the advance

 *               width of @glyph

 *

 * Since: 1.3.3

 **/

hb_position_t

hb_ot_math_get_glyph_top_accent_attachment (hb_font_t *font,

              hb_codepoint_t glyph)

{

  return font->face->table.MATH->get_glyph_info().get_top_accent_attachment (glyph, font);

}

/**

 * hb_ot_math_is_glyph_extended_shape:

 * @face: #hb_face_t to work upon

 * @glyph: The glyph index to test

 *

 * Tests whether the given glyph index is an extended shape in the face.

 *

 * 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)

{

  return face->table.MATH->get_glyph_info().is_extended_shape (glyph);

}

/**

 * hb_ot_math_get_glyph_kerning:

 * @font: #hb_font_t to work upon

 * @glyph: The 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.

 *

 * Fetches the math kerning (cut-ins) value for the specified font, glyph index, and

 * @kern. 

 *

 * If the MathKern table is found, the function examines it to find a height

 * value that is greater or equal to @correction_height. If such a height

 * value is found, corresponding kerning value from the table is returned. If

 * no such height value is found, the last kerning value is returned.

 *

 * Return value: requested kerning value or zero

 *

 * 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)

{

  return font->face->table.MATH->get_glyph_info().get_kerning (glyph,

                     kern,

                     correction_height,

                     font);

}

/**

 * hb_ot_math_get_glyph_kernings:

 * @font: #hb_font_t to work upon

 * @glyph: The glyph index from which to retrieve the kernings

 * @kern: The #hb_ot_math_kern_t from which to retrieve the kernings

 * @start_offset: offset of the first kern entry to retrieve

 * @entries_count: (inout) (optional): Input = the maximum number of kern entries to return;

 *                                     Output = the actual number of kern entries returned

 * @kern_entries: (out caller-allocates) (array length=entries_count): array of kern entries returned

 *

 * Fetches the raw MathKern (cut-in) data for the specified font, glyph index,

 * and @kern. The corresponding list of kern values and correction heights is

 * returned as a list of #hb_ot_math_kern_entry_t structs.

 *

 * See also #hb_ot_math_get_glyph_kerning, which handles selecting the

 * appropriate kern value for a given correction height.

 *

 * <note>For a glyph with @n defined kern values (where @n > 0), there are only

 * @n−1 defined correction heights, as each correction height defines a boundary

 * past which the next kern value should be selected. Therefore, only the

 * #hb_ot_math_kern_entry_t.kern_value of the uppermost #hb_ot_math_kern_entry_t

 * actually comes from the font; its corresponding

 * #hb_ot_math_kern_entry_t.max_correction_height is always set to

 * <code>INT32_MAX</code>.</note>

 *

 * Return value: the total number of kern values available or zero

 *

 * Since: 3.4.0

 **/

unsigned int

hb_ot_math_get_glyph_kernings (hb_font_t *font,

             hb_codepoint_t glyph,

             hb_ot_math_kern_t kern,

             unsigned int start_offset,

             unsigned int *entries_count, /* IN/OUT */

             hb_ot_math_kern_entry_t *kern_entries /* OUT */)

{

  return font->face->table.MATH->get_glyph_info().get_kernings (glyph,

                kern,

                start_offset,

                entries_count,

                kern_entries,

                font);

}

/**

 * hb_ot_math_get_glyph_variants:

 * @font: #hb_font_t to work upon

 * @glyph: The index of the glyph to stretch

 * @direction: The direction of the stretching (horizontal or vertical)

 * @start_offset: offset of the first variant to retrieve

 * @variants_count: (inout): Input = the maximum number of variants to return;

 *                           Output = the actual number of variants returned

 * @variants: (out) (array length=variants_count): array of variants returned

 *

 * Fetches the MathGlyphConstruction for the specified font, glyph index, and

 * direction. The corresponding list of size variants is returned as a list of

 * #hb_ot_math_glyph_variant_t structs.

 *

 * <note>The @direction parameter is only used to select between horizontal

 * or vertical directions for the construction. Even though all #hb_direction_t

 * values are accepted, only the result of #HB_DIRECTION_IS_HORIZONTAL is

 * considered.</note> 

 *

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

 *

 * 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 */)

{

  return font->face->table.MATH->get_variants().get_glyph_variants (glyph, direction, font,

                    start_offset,

                    variants_count,

                    variants);

}

/**

 * hb_ot_math_get_min_connector_overlap:

 * @font: #hb_font_t to work upon

 * @direction: direction of the stretching (horizontal or vertical)

 *

 * Fetches the MathVariants table for the specified font and returns the

 * minimum overlap of connecting glyphs that are required to draw a glyph

 * assembly in the specified direction.

 *

 * <note>The @direction parameter is only used to select between horizontal

 * or vertical directions for the construction. Even though all #hb_direction_t

 * values are accepted, only the result of #HB_DIRECTION_IS_HORIZONTAL is

 * considered.</note> 

 *

 * Return value: requested minimum connector overlap or zero

 *

 * Since: 1.3.3

 **/

hb_position_t

hb_ot_math_get_min_connector_overlap (hb_font_t *font,

              hb_direction_t direction)

{

  return font->face->table.MATH->get_variants().get_min_connector_overlap (direction, font);

}

/**

 * hb_ot_math_get_glyph_assembly:

 * @font: #hb_font_t to work upon

 * @glyph: The index of the glyph to stretch

 * @direction: direction of the stretching (horizontal or vertical)

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

 * @parts_count: (inout): Input = maximum number of glyph parts to return;

 *               Output = actual number of parts returned

 * @parts: (out) (array length=parts_count): the glyph parts returned

 * @italics_correction: (out): italics correction of the glyph assembly

 *

 * Fetches the GlyphAssembly for the specified font, glyph index, and direction.

 * Returned are a list of #hb_ot_math_glyph_part_t glyph parts that can be

 * used to draw the glyph and an italics-correction value (if one is defined

 * in the font).

 *

 * <note>The @direction parameter is only used to select between horizontal

 * or vertical directions for the construction. Even though all #hb_direction_t

 * values are accepted, only the result of #HB_DIRECTION_IS_HORIZONTAL is

 * considered.</note> 

 *

 * 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 */)

{

  return font->face->table.MATH->get_variants().get_glyph_parts (glyph,

                 direction,

                 font,

                 start_offset,

                 parts_count,

                 parts,

                 italics_correction);

}

#endif