#ifndef OT_LAYOUT_GSUB_SINGLESUBSTFORMAT2_HH

#define OT_LAYOUT_GSUB_SINGLESUBSTFORMAT2_HH

#include "Common.hh"

namespace OT {

namespace Layout {

namespace GSUB_impl {

template <typename Types>

struct SingleSubstFormat2_4

{

  protected:

  HBUINT16      format;                 /* Format identifier--format = 2 */

  typename Types::template OffsetTo<Coverage>

                coverage;               /* Offset to Coverage table--from

                                         * beginning of Substitution table */

  Array16Of<typename Types::HBGlyphID>

                substitute;             /* Array of substitute

                                         * GlyphIDs--ordered by Coverage Index */

  public:

  DEFINE_SIZE_ARRAY (4 + Types::size, substitute);

  bool sanitize (hb_sanitize_context_t *c) const

  {

    TRACE_SANITIZE (this);

    return_trace (coverage.sanitize (c, this) && substitute.sanitize (c));

  }

  bool intersects (const hb_set_t *glyphs) const

  { return (this+coverage).intersects (glyphs); }

  bool may_have_non_1to1 () const

  { return false; }

  void depend (hb_depend_context_t *c) const

  {

    auto &cov = this+coverage;

    auto &glyph_set = c->parent_active_glyphs ();

    // Filter by active glyphs like closure does

    if (substitute.len > glyph_set.get_population () * 4)

    {

      for (auto g : glyph_set)

      {

  unsigned i = cov.get_coverage (g);

  if (i == NOT_COVERED || i >= substitute.len)

    continue;

  c->depend_data->add_gsub_lookup (g, c->lookup_index, substitute.arrayZ[i]);

      }

      return;

    }

    + hb_zip (cov, substitute)

    | hb_filter (glyph_set, hb_first)

    | hb_apply ([&] (const hb_codepoint_pair_t &_) { c->depend_data->add_gsub_lookup (_.first, c->lookup_index, _.second); })

    ;

  }

  void closure (hb_closure_context_t *c) const

  {

    auto &cov = this+coverage;

    auto &glyph_set = c->parent_active_glyphs ();

    if (substitute.len > glyph_set.get_population () * 4)

    {

      for (auto g : glyph_set)

      {

  unsigned i = cov.get_coverage (g);

  if (i == NOT_COVERED || i >= substitute.len)

    continue;

  c->output->add (substitute.arrayZ[i]);

      }

      return;

    }

    + hb_zip (cov, substitute)

    | hb_filter (glyph_set, hb_first)

    | hb_map (hb_second)

    | hb_sink (c->output)

    ;

  }

  void closure_lookups (hb_closure_lookups_context_t *c) const {}

  void collect_glyphs (hb_collect_glyphs_context_t *c) const

  {

    if (unlikely (!(this+coverage).collect_coverage (c->input))) return;

    + hb_zip (this+coverage, substitute)

    | hb_map (hb_second)

    | hb_sink (c->output)

    ;

  }

  const Coverage &get_coverage () const { return this+coverage; }

  bool would_apply (hb_would_apply_context_t *c) const

  { return c->len == 1 && (this+coverage).get_coverage (c->glyphs[0]) != NOT_COVERED; }

  unsigned

  get_glyph_alternates (hb_codepoint_t  glyph_id,

                        unsigned        start_offset,

                        unsigned       *alternate_count  /* IN/OUT.  May be NULL. */,

                        hb_codepoint_t *alternate_glyphs /* OUT.     May be NULL. */) const

  {

    unsigned int index = (this+coverage).get_coverage (glyph_id);

    if (likely (index == NOT_COVERED))

    {

      if (alternate_count)

        *alternate_count = 0;

      return 0;

    }

    if (alternate_count && *alternate_count && alternate_glyphs)

    {

      glyph_id = substitute[index];

      *alternate_glyphs = glyph_id;

      *alternate_count = 1;

    }

    return 1;

  }

  void

  collect_glyph_alternates (hb_map_t  *alternate_count /* IN/OUT */,

          hb_map_t  *alternate_glyphs /* IN/OUT */) const

  {

    + hb_zip (this+coverage, substitute)

    | hb_apply ([&] (const hb_pair_t<hb_codepoint_t, hb_codepoint_t> &p) -> void

    { _hb_collect_glyph_alternates_add (p.first, p.second,

                alternate_count, alternate_glyphs); })

    ;

  }

  bool apply (hb_ot_apply_context_t *c) const

  {

    TRACE_APPLY (this);

    unsigned int index = (this+coverage).get_coverage (c->buffer->cur().codepoint);

    if (index == NOT_COVERED) return_trace (false);

    if (unlikely (index >= substitute.len)) return_trace (false);

    if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())

    {

      c->buffer->sync_so_far ();

      c->buffer->message (c->font,

        "replacing glyph at %u (single substitution)",

        c->buffer->idx);

    }

    c->replace_glyph (substitute[index]);

    if (HB_BUFFER_MESSAGE_MORE && c->buffer->messaging ())

    {

      c->buffer->message (c->font,

        "replaced glyph at %u (single substitution)",

        c->buffer->idx - 1u);

    }

    return_trace (true);

  }

  template<typename Iterator,

           hb_requires (hb_is_sorted_source_of (Iterator,

                                                hb_codepoint_pair_t))>

  bool serialize (hb_serialize_context_t *c,

                  Iterator it)

  {

    TRACE_SERIALIZE (this);

    auto substitutes =

      + it

      | hb_map (hb_second)

      ;

    auto glyphs =

      + it

      | hb_map_retains_sorting (hb_first)

      ;

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

    if (unlikely (!substitute.serialize (c, substitutes))) return_trace (false);

    if (unlikely (!coverage.serialize_serialize (c, glyphs))) return_trace (false);

    return_trace (true);

  }

Unexecuted instantiation: hb-ot-face.cc:_ZN2OT6Layout9GSUB_impl20SingleSubstFormat2_4INS0_10SmallTypesEE9serializeI13hb_map_iter_tI16hb_filter_iter_tIS6_IN23hb_bit_set_invertible_t6iter_tEZNKS1_20SingleSubstFormat1_3IS3_E6subsetEP19hb_subset_context_tEUljE_L24hb_function_sortedness_t1ELPv0EERK8hb_set_tRK3$_7LSG_0EEZNKSB_6subsetESD_EUl9hb_pair_tIjjEE_LSF_1ELSG_0EETnPN12hb_enable_ifIXaasr15hb_is_source_ofIT_SQ_EE5valuesrSU_18is_sorted_iteratorEvE4typeELSG_0EEEbP22hb_serialize_context_tSU_

Unexecuted instantiation: hb-ot-face.cc:_ZN2OT6Layout9GSUB_impl20SingleSubstFormat2_4INS0_10SmallTypesEE9serializeI13hb_map_iter_tI16hb_filter_iter_tIS7_I13hb_zip_iter_tINS0_6Common8Coverage6iter_tE10hb_array_tIKNS_11HBGlyphID16EEERK8hb_set_tRK3$_6LPv0EESJ_RK3$_7LSN_0EEZNKS4_6subsetEP19hb_subset_context_tEUl9hb_pair_tIjRSE_EE_L24hb_function_sortedness_t1ELSN_0EETnPN12hb_enable_ifIXaasr15hb_is_source_ofIT_SV_IjjEEE5valuesrS12_18is_sorted_iteratorEvE4typeELSN_0EEEbP22hb_serialize_context_tS12_

Unexecuted instantiation: hb-aat-layout.cc:_ZN2OT6Layout9GSUB_impl20SingleSubstFormat2_4INS0_10SmallTypesEE9serializeI13hb_map_iter_tI16hb_filter_iter_tIS6_IN23hb_bit_set_invertible_t6iter_tEZNKS1_20SingleSubstFormat1_3IS3_E6subsetEP19hb_subset_context_tEUljE_L24hb_function_sortedness_t1ELPv0EERK8hb_set_tRK3$_7LSG_0EEZNKSB_6subsetESD_EUl9hb_pair_tIjjEE_LSF_1ELSG_0EETnPN12hb_enable_ifIXaasr15hb_is_source_ofIT_SQ_EE5valuesrSU_18is_sorted_iteratorEvE4typeELSG_0EEEbP22hb_serialize_context_tSU_

Unexecuted instantiation: hb-aat-layout.cc:_ZN2OT6Layout9GSUB_impl20SingleSubstFormat2_4INS0_10SmallTypesEE9serializeI13hb_map_iter_tI16hb_filter_iter_tIS7_I13hb_zip_iter_tINS0_6Common8Coverage6iter_tE10hb_array_tIKNS_11HBGlyphID16EEERK8hb_set_tRK3$_6LPv0EESJ_RK3$_7LSN_0EEZNKS4_6subsetEP19hb_subset_context_tEUl9hb_pair_tIjRSE_EE_L24hb_function_sortedness_t1ELSN_0EETnPN12hb_enable_ifIXaasr15hb_is_source_ofIT_SV_IjjEEE5valuesrS12_18is_sorted_iteratorEvE4typeELSN_0EEEbP22hb_serialize_context_tS12_

Unexecuted instantiation: hb-ot-layout.cc:_ZN2OT6Layout9GSUB_impl20SingleSubstFormat2_4INS0_10SmallTypesEE9serializeI13hb_map_iter_tI16hb_filter_iter_tIS6_IN23hb_bit_set_invertible_t6iter_tEZNKS1_20SingleSubstFormat1_3IS3_E6subsetEP19hb_subset_context_tEUljE_L24hb_function_sortedness_t1ELPv0EERK8hb_set_tRK3$_7LSG_0EEZNKSB_6subsetESD_EUl9hb_pair_tIjjEE_LSF_1ELSG_0EETnPN12hb_enable_ifIXaasr15hb_is_source_ofIT_SQ_EE5valuesrSU_18is_sorted_iteratorEvE4typeELSG_0EEEbP22hb_serialize_context_tSU_

Unexecuted instantiation: hb-ot-layout.cc:_ZN2OT6Layout9GSUB_impl20SingleSubstFormat2_4INS0_10SmallTypesEE9serializeI13hb_map_iter_tI16hb_filter_iter_tIS7_I13hb_zip_iter_tINS0_6Common8Coverage6iter_tE10hb_array_tIKNS_11HBGlyphID16EEERK8hb_set_tRK3$_6LPv0EESJ_RK3$_7LSN_0EEZNKS4_6subsetEP19hb_subset_context_tEUl9hb_pair_tIjRSE_EE_L24hb_function_sortedness_t1ELSN_0EETnPN12hb_enable_ifIXaasr15hb_is_source_ofIT_SV_IjjEEE5valuesrS12_18is_sorted_iteratorEvE4typeELSN_0EEEbP22hb_serialize_context_tS12_

Unexecuted instantiation: _ZN2OT6Layout9GSUB_impl20SingleSubstFormat2_4INS0_10SmallTypesEE9serializeI13hb_zip_iter_tI17hb_sorted_array_tINS_11HBGlyphID16EE10hb_array_tIS8_EETnPN12hb_enable_ifIXaasr15hb_is_source_ofIT_9hb_pair_tIjjEEE5valuesrSE_18is_sorted_iteratorEvE4typeELPv0EEEbP22hb_serialize_context_tSE_

Unexecuted instantiation: hb-ot-shaper-arabic.cc:_ZN2OT6Layout9GSUB_impl20SingleSubstFormat2_4INS0_10SmallTypesEE9serializeI13hb_map_iter_tI16hb_filter_iter_tIS6_IN23hb_bit_set_invertible_t6iter_tEZNKS1_20SingleSubstFormat1_3IS3_E6subsetEP19hb_subset_context_tEUljE_L24hb_function_sortedness_t1ELPv0EERK8hb_set_tRK3$_7LSG_0EEZNKSB_6subsetESD_EUl9hb_pair_tIjjEE_LSF_1ELSG_0EETnPN12hb_enable_ifIXaasr15hb_is_source_ofIT_SQ_EE5valuesrSU_18is_sorted_iteratorEvE4typeELSG_0EEEbP22hb_serialize_context_tSU_

Unexecuted instantiation: hb-ot-shaper-arabic.cc:_ZN2OT6Layout9GSUB_impl20SingleSubstFormat2_4INS0_10SmallTypesEE9serializeI13hb_map_iter_tI16hb_filter_iter_tIS7_I13hb_zip_iter_tINS0_6Common8Coverage6iter_tE10hb_array_tIKNS_11HBGlyphID16EEERK8hb_set_tRK3$_6LPv0EESJ_RK3$_7LSN_0EEZNKS4_6subsetEP19hb_subset_context_tEUl9hb_pair_tIjRSE_EE_L24hb_function_sortedness_t1ELSN_0EETnPN12hb_enable_ifIXaasr15hb_is_source_ofIT_SV_IjjEEE5valuesrS12_18is_sorted_iteratorEvE4typeELSN_0EEEbP22hb_serialize_context_tS12_

  bool subset (hb_subset_context_t *c) const

  {

    TRACE_SUBSET (this);

    const hb_set_t &glyphset = *c->plan->glyphset_gsub ();

    const hb_map_t &glyph_map = *c->plan->glyph_map;

    auto it =

    + hb_zip (this+coverage, substitute)

    | hb_filter (glyphset, hb_first)

    | hb_filter (glyphset, hb_second)

    | hb_map_retains_sorting ([&] (hb_pair_t<hb_codepoint_t, const typename Types::HBGlyphID &> p) -> hb_codepoint_pair_t

                              { return hb_pair (glyph_map[p.first], glyph_map[p.second]); })

    ;

    bool ret = bool (it);

    SingleSubst_serialize (c->serializer, it);

    return_trace (ret);

  }

};

}

}

}

#endif /* OT_LAYOUT_GSUB_SINGLESUBSTFORMAT2_HH */