/*

 * Copyright © 2017  Google, Inc.

 *

 *  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.

 *

 * Google Author(s): Behdad Esfahbod

 */

#ifndef HB_OT_VAR_MVAR_TABLE_HH

#define HB_OT_VAR_MVAR_TABLE_HH

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

namespace OT {

struct VariationValueRecord

{

  inline bool sanitize (hb_sanitize_context_t *c) const

  {

    TRACE_SANITIZE (this);

    return_trace (c->check_struct (this));

  }

  public:

  Tag		valueTag;	/* Four-byte tag identifying a font-wide measure. */

  ULONG		varIdx;		/* Outer/inner index into VariationStore item. */

  public:

  DEFINE_SIZE_STATIC (8);

};

/*

 * MVAR -- Metrics Variations Table

 */

#define HB_OT_TAG_MVAR HB_TAG('M','V','A','R')

struct MVAR

{

  static const hb_tag_t tableTag	= HB_OT_TAG_MVAR;

  inline bool sanitize (hb_sanitize_context_t *c) const

  {

    TRACE_SANITIZE (this);

    return_trace (version.sanitize (c) &&

		  likely (version.major == 1) &&

		  c->check_struct (this) &&

		  valueRecordSize >= VariationValueRecord::static_size &&

		  varStore.sanitize (c, this) &&

		  c->check_array (values, valueRecordSize, valueRecordCount));

  }

  inline float get_var (hb_tag_t tag,

			int *coords, unsigned int coord_count) const

  {

    const VariationValueRecord *record;

    record = (VariationValueRecord *) bsearch (&tag, values,

					       valueRecordCount, valueRecordSize,

					       (hb_compare_func_t) tag_compare);

    if (!record)

      return 0.;

    return (this+varStore).get_delta (record->varIdx, coords, coord_count);

  }

protected:

  static inline int tag_compare (const hb_tag_t *a, const Tag *b)

  { return b->cmp (*a); }

  protected:

  FixedVersion<>version;	/* Version of the metrics variation table

				 * initially set to 0x00010000u */

  USHORT	reserved;	/* Not used; set to 0. */

  USHORT	valueRecordSize;/* The size in bytes of each value record —

				 * must be greater than zero. */

  USHORT	valueRecordCount;/* The number of value records — may be zero. */

  OffsetTo<VariationStore>

		varStore;	/* Offset to item variation store table. */

  BYTE		values[VAR];	/* Array of value records. The records must be

				 * in binary order of their valueTag field. */

  public:

  DEFINE_SIZE_ARRAY (12, values);

};

} /* namespace OT */

#endif /* HB_OT_VAR_MVAR_TABLE_HH */