/*

 * Copyright © 2018  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): Garret Rieger

 */

#ifndef HB_OT_HDMX_TABLE_HH

#define HB_OT_HDMX_TABLE_HH

#include "hb-open-type.hh"

/*

 * hdmx -- Horizontal Device Metrics

 * https://docs.microsoft.com/en-us/typography/opentype/spec/hdmx

 */

#define HB_OT_TAG_hdmx HB_TAG('h','d','m','x')

namespace OT {

struct DeviceRecord

{

  static unsigned int get_size (unsigned count)

  { return hb_ceil_to_4 (min_size + count * HBUINT8::static_size); }

  template<typename Iterator,

     hb_requires (hb_is_iterator (Iterator))>

  bool serialize (hb_serialize_context_t *c,

      unsigned pixelSize,

      Iterator it,

      const hb_vector_t<hb_codepoint_pair_t> new_to_old_gid_list,

      unsigned num_glyphs)

  {

    TRACE_SERIALIZE (this);

    if (unlikely (!c->extend (this, num_glyphs)))  return_trace (false);

    this->pixelSize = pixelSize;

    this->maxWidth =

    + it

    | hb_reduce (hb_max, 0u);

    for (auto &_ : new_to_old_gid_list)

      widthsZ[_.first] = *it++;

    return_trace (true);

  }

  bool sanitize (hb_sanitize_context_t *c, unsigned sizeDeviceRecord) const

  {

    TRACE_SANITIZE (this);

    return_trace (likely (c->check_struct (this) &&

        hb_barrier () &&

        c->check_range (this, sizeDeviceRecord)));

  }

  HBUINT8     pixelSize;  /* Pixel size for following widths (as ppem). */

  HBUINT8     maxWidth; /* Maximum width. */

  UnsizedArrayOf<HBUINT8> widthsZ;  /* Array of widths (numGlyphs is from the 'maxp' table). */

  public:

  DEFINE_SIZE_UNBOUNDED (2);

};

struct hdmx

{

  static constexpr hb_tag_t tableTag = HB_OT_TAG_hdmx;

  unsigned int get_size () const

  { return min_size + numRecords * sizeDeviceRecord; }

  template<typename Iterator,

     hb_requires (hb_is_iterator (Iterator))>

  bool serialize (hb_serialize_context_t *c,

      unsigned version,

      Iterator it,

      const hb_vector_t<hb_codepoint_pair_t> &new_to_old_gid_list,

      unsigned num_glyphs)

  {

    TRACE_SERIALIZE (this);

    if (unlikely (!c->extend_min ((*this))))  return_trace (false);

    this->version = version;

    this->numRecords = it.len ();

    this->sizeDeviceRecord = DeviceRecord::get_size (num_glyphs);

    for (const hb_item_type<Iterator>& _ : +it)

      c->start_embed<DeviceRecord> ()->serialize (c, _.first, _.second, new_to_old_gid_list, num_glyphs);

    return_trace (c->successful ());

  }

  bool subset (hb_subset_context_t *c) const

  {

    TRACE_SUBSET (this);

    auto *hdmx_prime = c->serializer->start_embed <hdmx> ();

    unsigned num_input_glyphs = get_num_glyphs ();

    auto it =

    + hb_range ((unsigned) numRecords)

    | hb_map ([c, num_input_glyphs, this] (unsigned _)

  {

    const DeviceRecord *device_record =

      &StructAtOffset<DeviceRecord> (&firstDeviceRecord,

             _ * sizeDeviceRecord);

    auto row =

      + hb_iter (c->plan->new_to_old_gid_list)

      | hb_map ([num_input_glyphs, device_record] (hb_codepoint_pair_t _)

          {

      return device_record->widthsZ.as_array (num_input_glyphs) [_.second];

          })

      ;

    return hb_pair ((unsigned) device_record->pixelSize, +row);

  })

    ;

    hdmx_prime->serialize (c->serializer, version, it,

         c->plan->new_to_old_gid_list,

         c->plan->num_output_glyphs ());

    return_trace (true);

  }

  unsigned get_num_glyphs () const

  {

    return sizeDeviceRecord - DeviceRecord::min_size;

  }

  bool sanitize (hb_sanitize_context_t *c) const

  {

    TRACE_SANITIZE (this);

    return_trace (c->check_struct (this) &&

      hb_barrier () &&

      !hb_unsigned_mul_overflows (numRecords, sizeDeviceRecord) &&

                  min_size + numRecords * sizeDeviceRecord > numRecords * sizeDeviceRecord &&

      sizeDeviceRecord >= DeviceRecord::min_size &&

      c->check_range (this, get_size ()));

  }

  protected:

  HBUINT16  version;  /* Table version number (0) */

  HBUINT16  numRecords; /* Number of device records. */

  HBUINT32  sizeDeviceRecord;

        /* Size of a device record, 32-bit aligned. */

  DeviceRecord  firstDeviceRecord;

        /* Array of device records. */

  public:

  DEFINE_SIZE_MIN (8);

};

} /* namespace OT */

#endif /* HB_OT_HDMX_TABLE_HH */