#ifndef OT_LAYOUT_GPOS_PAIRSET_HH

#define OT_LAYOUT_GPOS_PAIRSET_HH

#include "PairValueRecord.hh"

namespace OT {

namespace Layout {

namespace GPOS_impl {

template <typename Types>

struct PairSet

{

  template <typename Types2>

  friend struct PairPosFormat1_3;

  using PairValueRecord = GPOS_impl::PairValueRecord<Types>;

  protected:

  HBUINT16              len;    /* Number of PairValueRecords */

  PairValueRecord       firstPairValueRecord;

                                /* Array of PairValueRecords--ordered

                                 * by GlyphID of the second glyph */

  public:

  DEFINE_SIZE_MIN (2);

  static unsigned get_size (unsigned len1, unsigned len2)

  {

    return Types::HBGlyphID::static_size + Value::static_size * (len1 + len2);

  }

  static unsigned get_size (const ValueFormat valueFormats[2])

  {

    unsigned len1 = valueFormats[0].get_len ();

    unsigned len2 = valueFormats[1].get_len ();

    return get_size (len1, len2);

  }

  struct sanitize_closure_t

  {

    const ValueFormat *valueFormats;

    unsigned int len1; /* valueFormats[0].get_len() */

    unsigned int stride; /* bytes */

  };

  bool sanitize (hb_sanitize_context_t *c, const sanitize_closure_t *closure) const

  {

    TRACE_SANITIZE (this);

    if (!(c->check_struct (this)

       && c->check_range (&firstPairValueRecord,

                          len,

                          closure->stride))) return_trace (false);

    unsigned int count = len;

    const PairValueRecord *record = &firstPairValueRecord;

    return_trace (closure->valueFormats[0].sanitize_values_stride_unsafe (c, this, &record->values[0], count, closure->stride) &&

                  closure->valueFormats[1].sanitize_values_stride_unsafe (c, this, &record->values[closure->len1], count, closure->stride));

  }

  bool intersects (const hb_set_t *glyphs,

                   const ValueFormat *valueFormats) const

  {

    unsigned record_size = get_size (valueFormats);

    const PairValueRecord *record = &firstPairValueRecord;

    unsigned int count = len;

    for (unsigned int i = 0; i < count; i++)

    {

      if (glyphs->has (record->secondGlyph))

        return true;

      record = &StructAtOffset<const PairValueRecord> (record, record_size);

    }

    return false;

  }

  void collect_glyphs (hb_collect_glyphs_context_t *c,

                       const ValueFormat *valueFormats) const

  {

    unsigned record_size = get_size (valueFormats);

    const PairValueRecord *record = &firstPairValueRecord;

    c->input->add_array (&record->secondGlyph, len, record_size);

  }

  void collect_variation_indices (hb_collect_variation_indices_context_t *c,

                                  const ValueFormat *valueFormats) const

  {

    unsigned record_size = get_size (valueFormats);

    const PairValueRecord *record = &firstPairValueRecord;

    unsigned count = len;

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

    {

      if (c->glyph_set->has (record->secondGlyph))

      { record->collect_variation_indices (c, valueFormats, this); }

      record = &StructAtOffset<const PairValueRecord> (record, record_size);

    }

  }

  bool apply (hb_ot_apply_context_t *c,

              const ValueFormat *valueFormats,

              unsigned int pos) const

  {

    TRACE_APPLY (this);

    hb_buffer_t *buffer = c->buffer;

    unsigned int len1 = valueFormats[0].get_len ();

    unsigned int len2 = valueFormats[1].get_len ();

    unsigned record_size = get_size (len1, len2);

    const PairValueRecord *record = hb_bsearch (buffer->info[pos].codepoint,

                                                &firstPairValueRecord,

                                                len,

                                                record_size);

    if (record)

    {

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

      {

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

          "try kerning glyphs at %u,%u",

          c->buffer->idx, pos);

      }

      bool applied_first = len1 && valueFormats[0].apply_value (c, this, &record->values[0], buffer->cur_pos());

      bool applied_second = len2 && valueFormats[1].apply_value (c, this, &record->values[len1], buffer->pos[pos]);

      if (applied_first || applied_second)

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

  {

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

            "kerned glyphs at %u,%u",

            c->buffer->idx, pos);

  }

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

      {

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

          "tried kerning glyphs at %u,%u",

          c->buffer->idx, pos);

      }

      if (applied_first || applied_second)

        buffer->unsafe_to_break (buffer->idx, pos + 1);

      if (len2)

      {

  pos++;

      // https://github.com/harfbuzz/harfbuzz/issues/3824

      // https://github.com/harfbuzz/harfbuzz/issues/3888#issuecomment-1326781116

      buffer->unsafe_to_break (buffer->idx, pos + 1);

      }

      buffer->idx = pos;

      return_trace (true);

    }

    buffer->unsafe_to_concat (buffer->idx, pos + 1);

    return_trace (false);

  }

  bool subset (hb_subset_context_t *c,

               const ValueFormat valueFormats[2],

               const ValueFormat newFormats[2]) const

  {

    TRACE_SUBSET (this);

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

    auto *out = c->serializer->start_embed (*this);

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

    out->len = 0;

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

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

    unsigned len1 = valueFormats[0].get_len ();

    unsigned len2 = valueFormats[1].get_len ();

    unsigned record_size = get_size (len1, len2);

    typename PairValueRecord::context_t context =

    {

      this,

      valueFormats,

      newFormats,

      len1,

      &glyph_map,

      &c->plan->layout_variation_idx_delta_map

    };

    const PairValueRecord *record = &firstPairValueRecord;

    unsigned count = len, num = 0;

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

    {

      if (glyphset.has (record->secondGlyph)

         && record->subset (c, &context)) num++;

      record = &StructAtOffset<const PairValueRecord> (record, record_size);

    }

    out->len = num;

    if (!num) c->serializer->revert (snap);

    return_trace (num);

  }

};

}

}

}

#endif  // OT_LAYOUT_GPOS_PAIRSET_HH