#ifndef OT_LAYOUT_GSUB_LIGATURESET_HH

#define OT_LAYOUT_GSUB_LIGATURESET_HH

#include "Common.hh"

#include "Ligature.hh"

namespace OT {

namespace Layout {

namespace GSUB_impl {

template <typename Types>

struct LigatureSet

{

  public:

  Array16OfOffset16To<Ligature<Types>>

                ligature;               /* Array LigatureSet tables

                                         * ordered by preference */

  DEFINE_SIZE_ARRAY (2, ligature);

  bool sanitize (hb_sanitize_context_t *c) const

  {

    TRACE_SANITIZE (this);

    return_trace (ligature.sanitize (c, this));

  }

  bool intersects (const hb_set_t *glyphs) const

  {

    return

    + hb_iter (ligature)

    | hb_map (hb_add (this))

    | hb_map ([glyphs] (const Ligature<Types> &_) { return _.intersects (glyphs); })

    | hb_any

    ;

  }

  bool intersects_lig_glyph (const hb_set_t *glyphs) const

  {

    return

    + hb_iter (ligature)

    | hb_map (hb_add (this))

    | hb_map ([glyphs] (const Ligature<Types> &_) { 

      return _.intersects_lig_glyph (glyphs) && _.intersects (glyphs);

    })

    | hb_any

    ;

  }

  void closure (hb_closure_context_t *c) const

  {

    + hb_iter (ligature)

    | hb_map (hb_add (this))

    | hb_apply ([c] (const Ligature<Types> &_) { _.closure (c); })

    ;

  }

  void collect_glyphs (hb_collect_glyphs_context_t *c) const

  {

    + hb_iter (ligature)

    | hb_map (hb_add (this))

    | hb_apply ([c] (const Ligature<Types> &_) { _.collect_glyphs (c); })

    ;

  }

  template <typename set_t>

  void collect_seconds (set_t &s) const

  {

    + hb_iter (ligature)

    | hb_map (hb_add (this))

    | hb_apply ([&s] (const Ligature<Types> &_) { _.collect_second (s); })

    ;

  }

  bool would_apply (hb_would_apply_context_t *c) const

  {

    return

    + hb_iter (ligature)

    | hb_map (hb_add (this))

    | hb_map ([c] (const Ligature<Types> &_) { return _.would_apply (c); })

    | hb_any

    ;

  }

  bool apply (hb_ot_apply_context_t *c, const hb_set_digest_t *seconds = nullptr) const

  {

    TRACE_APPLY (this);

    unsigned int num_ligs = ligature.len;

#ifndef HB_NO_OT_RULESETS_FAST_PATH

    if (HB_OPTIMIZE_SIZE_VAL || num_ligs <= 1)

#endif

    {

    slow:

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

      {

  const auto &lig = this+ligature.arrayZ[i];

  if (lig.apply (c)) return_trace (true);

      }

      return_trace (false);

    }

    /* This version is optimized for speed by matching the second component

     * of the ligature here, instead of calling into the ligation code.

     *

     * This is replicated in ChainRuleSet and RuleSet. */

    auto &skippy_iter = c->iter_input;

    skippy_iter.reset (c->buffer->idx);

    skippy_iter.set_match_func (match_always, nullptr);

    skippy_iter.set_glyph_data ((HBUINT16 *) nullptr);

    unsigned unsafe_to;

    hb_codepoint_t second = (unsigned) -1;

    bool matched = skippy_iter.next (&unsafe_to);

    if (likely (matched))

    {

      second = c->buffer->info[skippy_iter.idx].codepoint;

      unsafe_to = skippy_iter.idx + 1;

      if (skippy_iter.may_skip (c->buffer->info[skippy_iter.idx]))

      {

  /* Can't use the fast path if eg. the next char is a default-ignorable

   * or other skippable. */

        goto slow;

      }

    }

    else

      goto slow;

    if (seconds && !seconds->may_have (second))

      return_trace (false);

    bool unsafe_to_concat = false;

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

    {

      const auto &lig = this+ligature.arrayZ[i];

      if (unlikely (lig.component.lenP1 <= 1) ||

    lig.component.arrayZ[0] == second)

      {

  if (lig.apply (c))

  {

    if (unsafe_to_concat)

      c->buffer->unsafe_to_concat (c->buffer->idx, unsafe_to);

    return_trace (true);

  }

      }

      else if (likely (lig.component.lenP1 > 1))

        unsafe_to_concat = true;

    }

    if (likely (unsafe_to_concat))

      c->buffer->unsafe_to_concat (c->buffer->idx, unsafe_to);

    return_trace (false);

  }

  bool serialize (hb_serialize_context_t *c,

                  hb_array_t<const HBGlyphID16> ligatures,

                  hb_array_t<const unsigned int> component_count_list,

                  hb_array_t<const HBGlyphID16> &component_list /* Starting from second for each ligature */)

  {

    TRACE_SERIALIZE (this);

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

    if (unlikely (!ligature.serialize (c, ligatures.length))) return_trace (false);

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

    {

      unsigned int component_count = (unsigned) hb_max ((int) component_count_list[i] - 1, 0);

      if (unlikely (!ligature[i].serialize_serialize (c,

                                                      ligatures[i],

                                                      component_list.sub_array (0, component_count))))

        return_trace (false);

      component_list += component_count;

    }

    return_trace (true);

  }

  bool subset (hb_subset_context_t *c, unsigned coverage_idx) const

  {

    TRACE_SUBSET (this);

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

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

    + hb_iter (ligature)

    | hb_filter (subset_offset_array (c, out->ligature, this, coverage_idx))

    | hb_drain

    ;

    if (bool (out->ligature))

      // Ensure Coverage table is always packed after this.

      c->serializer->add_virtual_link (coverage_idx);

    return_trace (bool (out->ligature));

  }

};

}

}

}

#endif  /* OT_LAYOUT_GSUB_LIGATURESET_HH */