/*

 * 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_FVAR_TABLE_HH

#define HB_OT_VAR_FVAR_TABLE_HH

#include "hb-open-type.hh"

/*

 * fvar -- Font Variations

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

 */

#define HB_OT_TAG_fvar HB_TAG('f','v','a','r')

namespace OT {

struct InstanceRecord

{

  friend struct fvar;

  hb_array_t<const F16DOT16> get_coordinates (unsigned int axis_count) const

  { return coordinatesZ.as_array (axis_count); }

  bool subset (hb_subset_context_t *c,

               unsigned axis_count,

               bool has_postscript_nameid) const

  {

    TRACE_SUBSET (this);

    if (unlikely (!c->serializer->embed (subfamilyNameID))) return_trace (false);

    if (unlikely (!c->serializer->embed (flags))) return_trace (false);

    const hb_array_t<const F16DOT16> coords = get_coordinates (axis_count);

    const hb_hashmap_t<hb_tag_t, float> *axes_location = &c->plan->user_axes_location;

    for (unsigned i = 0 ; i < axis_count; i++)

    {

      uint32_t *axis_tag;

      // only keep instances whose coordinates == pinned axis location

      if (!c->plan->axes_old_index_tag_map.has (i, &axis_tag)) continue;

      if (axes_location->has (*axis_tag) &&

          fabsf (axes_location->get (*axis_tag) - coords[i].to_float ()) > 0.001f)

        return_trace (false);

      if (!c->plan->axes_index_map.has (i))

        continue;

      if (!c->serializer->embed (coords[i]))

        return_trace (false);

    }

    if (has_postscript_nameid)

    {

      NameID name_id;

      name_id = StructAfter<NameID> (coords);

      if (!c->serializer->embed (name_id))

        return_trace (false);

    }

    return_trace (true);

  }

  bool sanitize (hb_sanitize_context_t *c, unsigned int axis_count) const

  {

    TRACE_SANITIZE (this);

    return_trace (c->check_struct (this) &&

      c->check_array (coordinatesZ.arrayZ, axis_count));

  }

  protected:

  NameID  subfamilyNameID;/* The name ID for entries in the 'name' table

         * that provide subfamily names for this instance. */

  HBUINT16  flags;    /* Reserved for future use — set to 0. */

  UnsizedArrayOf<F16DOT16>

    coordinatesZ; /* The coordinates array for this instance. */

  //NameID  postScriptNameIDX;/*Optional. The name ID for entries in the 'name'

  //          * table that provide PostScript names for this

  //          * instance. */

  public:

  DEFINE_SIZE_UNBOUNDED (4);

};

struct AxisRecord

{

  int cmp (hb_tag_t key) const { return axisTag.cmp (key); }

  enum

  {

    AXIS_FLAG_HIDDEN  = 0x0001,

  };

#ifndef HB_DISABLE_DEPRECATED

  void get_axis_deprecated (hb_ot_var_axis_t *info) const

  {

    info->tag = axisTag;

    info->name_id = axisNameID;

    get_coordinates (info->min_value, info->default_value, info->max_value);

  }

#endif

  void get_axis_info (unsigned axis_index, hb_ot_var_axis_info_t *info) const

  {

    info->axis_index = axis_index;

    info->tag = axisTag;

    info->name_id = axisNameID;

    info->flags = (hb_ot_var_axis_flags_t) (unsigned int) flags;

    get_coordinates (info->min_value, info->default_value, info->max_value);

    info->reserved = 0;

  }

  hb_tag_t get_axis_tag () const { return axisTag; }

  int normalize_axis_value (float v) const

  {

    float min_value, default_value, max_value;

    get_coordinates (min_value, default_value, max_value);

    v = hb_clamp (v, min_value, max_value);

    if (v == default_value)

      return 0;

    else if (v < default_value)

      v = (v - default_value) / (default_value - min_value);

    else

      v = (v - default_value) / (max_value - default_value);

    return roundf (v * 16384.f);

  }

  float unnormalize_axis_value (int v) const

  {

    float min_value, default_value, max_value;

    get_coordinates (min_value, default_value, max_value);

    if (v == 0)

      return default_value;

    else if (v < 0)

      return v * (default_value - min_value) / 16384.f + default_value;

    else

      return v * (max_value - default_value) / 16384.f + default_value;

  }

  hb_ot_name_id_t get_name_id () const { return axisNameID; }

  bool sanitize (hb_sanitize_context_t *c) const

  {

    TRACE_SANITIZE (this);

    return_trace (c->check_struct (this));

  }

  void get_coordinates (float &min, float &default_, float &max) const

  {

    default_ = defaultValue.to_float ();

    /* Ensure order, to simplify client math. */

    min = hb_min (default_, minValue.to_float ());

    max = hb_max (default_, maxValue.to_float ());

  }

  float get_default () const

  {

    return defaultValue.to_float ();

  }

  public:

  Tag   axisTag;  /* Tag identifying the design variation for the axis. */

  protected:

  F16DOT16  minValue; /* The minimum coordinate value for the axis. */

  F16DOT16  defaultValue; /* The default coordinate value for the axis. */

  F16DOT16  maxValue; /* The maximum coordinate value for the axis. */

  public:

  HBUINT16  flags;    /* Axis flags. */

  NameID  axisNameID; /* The name ID for entries in the 'name' table that

         * provide a display name for this axis. */

  public:

  DEFINE_SIZE_STATIC (20);

};

struct fvar

{

  static constexpr hb_tag_t tableTag = HB_OT_TAG_fvar;

  bool has_data () const { return version.to_int (); }

  bool sanitize (hb_sanitize_context_t *c) const

  {

    TRACE_SANITIZE (this);

    return_trace (version.sanitize (c) &&

      likely (version.major == 1) &&

      c->check_struct (this) &&

      axisSize == 20 && /* Assumed in our code. */

      instanceSize >= axisCount * 4 + 4 &&

      get_axes ().sanitize (c) &&

      c->check_range (get_instance (0), instanceCount, instanceSize));

  }

  unsigned int get_axis_count () const { return axisCount; }

#ifndef HB_DISABLE_DEPRECATED

  unsigned int get_axes_deprecated (unsigned int      start_offset,

            unsigned int     *axes_count /* IN/OUT */,

            hb_ot_var_axis_t *axes_array /* OUT */) const

  {

    if (axes_count)

    {

      hb_array_t<const AxisRecord> arr = get_axes ().sub_array (start_offset, axes_count);

      for (unsigned i = 0; i < arr.length; ++i)

  arr[i].get_axis_deprecated (&axes_array[i]);

    }

    return axisCount;

  }

#endif

  unsigned int get_axis_infos (unsigned int           start_offset,

             unsigned int          *axes_count /* IN/OUT */,

             hb_ot_var_axis_info_t *axes_array /* OUT */) const

  {

    if (axes_count)

    {

      hb_array_t<const AxisRecord> arr = get_axes ().sub_array (start_offset, axes_count);

      for (unsigned i = 0; i < arr.length; ++i)

  arr[i].get_axis_info (start_offset + i, &axes_array[i]);

    }

    return axisCount;

  }

#ifndef HB_DISABLE_DEPRECATED

  bool

  find_axis_deprecated (hb_tag_t tag, unsigned *axis_index, hb_ot_var_axis_t *info) const

  {

    unsigned i;

    if (!axis_index) axis_index = &i;

    *axis_index = HB_OT_VAR_NO_AXIS_INDEX;

    auto axes = get_axes ();

    return axes.lfind (tag, axis_index) && ((void) axes[*axis_index].get_axis_deprecated (info), true);

  }

#endif

  bool

  find_axis_info (hb_tag_t tag, hb_ot_var_axis_info_t *info) const

  {

    unsigned i;

    auto axes = get_axes ();

    return axes.lfind (tag, &i) && ((void) axes[i].get_axis_info (i, info), true);

  }

  int normalize_axis_value (unsigned int axis_index, float v) const

  { return get_axes ()[axis_index].normalize_axis_value (v); }

  float unnormalize_axis_value (unsigned int axis_index, int v) const

  { return get_axes ()[axis_index].unnormalize_axis_value (v); }

  unsigned int get_instance_count () const { return instanceCount; }

  hb_ot_name_id_t get_instance_subfamily_name_id (unsigned int instance_index) const

  {

    const InstanceRecord *instance = get_instance (instance_index);

    if (unlikely (!instance)) return HB_OT_NAME_ID_INVALID;

    return instance->subfamilyNameID;

  }

  hb_ot_name_id_t get_instance_postscript_name_id (unsigned int instance_index) const

  {

    const InstanceRecord *instance = get_instance (instance_index);

    if (unlikely (!instance)) return HB_OT_NAME_ID_INVALID;

    if (instanceSize >= axisCount * 4 + 6)

      return StructAfter<NameID> (instance->get_coordinates (axisCount));

    return HB_OT_NAME_ID_INVALID;

  }

  unsigned int get_instance_coords (unsigned int  instance_index,

            unsigned int *coords_length, /* IN/OUT */

            float        *coords         /* OUT */) const

  {

    const InstanceRecord *instance = get_instance (instance_index);

    if (unlikely (!instance))

    {

      if (coords_length)

  *coords_length = 0;

      return 0;

    }

    if (coords_length && *coords_length)

    {

      hb_array_t<const F16DOT16> instanceCoords = instance->get_coordinates (axisCount)

               .sub_array (0, coords_length);

      for (unsigned int i = 0; i < instanceCoords.length; i++)

  coords[i] = instanceCoords.arrayZ[i].to_float ();

    }

    return axisCount;

  }

  void collect_name_ids (hb_hashmap_t<hb_tag_t, float> *user_axes_location,

       hb_set_t *nameids  /* IN/OUT */) const

  {

    if (!has_data ()) return;

    hb_map_t pinned_axes;

    auto axis_records = get_axes ();

    for (unsigned i = 0 ; i < (unsigned)axisCount; i++)

    {

      hb_tag_t axis_tag = axis_records[i].get_axis_tag ();

      if (user_axes_location->has (axis_tag))

      {

        pinned_axes.set (i, axis_tag);

        continue;

      }

      nameids->add (axis_records[i].get_name_id ());

    }

    for (unsigned i = 0 ; i < (unsigned)instanceCount; i++)

    {

      const InstanceRecord *instance = get_instance (i);

      if (hb_any (+ hb_enumerate (instance->get_coordinates (axisCount))

                  | hb_filter (pinned_axes, hb_first)

                  | hb_map ([&] (const hb_pair_t<unsigned, const F16DOT16&>& _)

                            {

                              hb_tag_t axis_tag = pinned_axes.get (_.first);

                              float location = user_axes_location->get (axis_tag);

                              if (fabs ((double)location - (double)_.second.to_float ()) > 0.001) return true;

                              return false;

                            })

                  ))

        continue;

      nameids->add (instance->subfamilyNameID);

      if (instanceSize >= axisCount * 4 + 6)

      {

        unsigned post_script_name_id = StructAfter<NameID> (instance->get_coordinates (axisCount));

        if (post_script_name_id != HB_OT_NAME_ID_INVALID) nameids->add (post_script_name_id);

      }

    }

  }

  bool subset (hb_subset_context_t *c) const

  {

    TRACE_SUBSET (this);

    unsigned retained_axis_count = c->plan->axes_index_map.get_population ();

    if (!retained_axis_count) //all axes are pinned

      return_trace (false);

    fvar *out = c->serializer->embed (this);

    if (unlikely (!out)) return_trace (false);

    if (!c->serializer->check_assign (out->axisCount, retained_axis_count, HB_SERIALIZE_ERROR_INT_OVERFLOW))

      return_trace (false);

    bool has_postscript_nameid = false;

    if (instanceSize >= axisCount * 4 + 6)

      has_postscript_nameid = true;

    if (!c->serializer->check_assign (out->instanceSize, retained_axis_count * 4 + (has_postscript_nameid ? 6 : 4),

                                      HB_SERIALIZE_ERROR_INT_OVERFLOW))

      return_trace (false);

    auto axes_records = get_axes ();

    for (unsigned i = 0 ; i < (unsigned)axisCount; i++)

    {

      if (!c->plan->axes_index_map.has (i)) continue;

      if (unlikely (!c->serializer->embed (axes_records[i])))

        return_trace (false);

    }

    if (!c->serializer->check_assign (out->firstAxis, get_size (), HB_SERIALIZE_ERROR_INT_OVERFLOW))

      return_trace (false);

    for (unsigned i = 0 ; i < (unsigned)instanceCount; i++)

    {

      const InstanceRecord *instance = get_instance (i);

      auto snap = c->serializer->snapshot ();

      if (!instance->subset (c, axisCount, has_postscript_nameid))

        c->serializer->revert (snap);

    }

    return_trace (true);

  }

  public:

  hb_array_t<const AxisRecord> get_axes () const

  { return hb_array (&(this+firstAxis), axisCount); }

  const InstanceRecord *get_instance (unsigned int i) const

  {

    if (unlikely (i >= instanceCount)) return nullptr;

   return &StructAtOffset<InstanceRecord> (&StructAfter<InstanceRecord> (get_axes ()),

             i * instanceSize);

  }

  protected:

  FixedVersion<>version;  /* Version of the fvar table

         * initially set to 0x00010000u */

  Offset16To<AxisRecord>

    firstAxis;  /* Offset in bytes from the beginning of the table

         * to the start of the AxisRecord array. */

  HBUINT16  reserved; /* This field is permanently reserved. Set to 2. */

  HBUINT16  axisCount;  /* The number of variation axes in the font (the

         * number of records in the axes array). */

  HBUINT16  axisSize; /* The size in bytes of each VariationAxisRecord —

         * set to 20 (0x0014) for this version. */

  HBUINT16  instanceCount;  /* The number of named instances defined in the font

         * (the number of records in the instances array). */

  HBUINT16  instanceSize; /* The size in bytes of each InstanceRecord — set

         * to either axisCount * sizeof(F16DOT16) + 4, or to

         * axisCount * sizeof(F16DOT16) + 6. */

  public:

  DEFINE_SIZE_STATIC (16);

};

} /* namespace OT */

#endif /* HB_OT_VAR_FVAR_TABLE_HH */