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 /*

  * Copyright © 2009,2010  Red Hat, Inc.

  * Copyright © 2010,2011,2012,2013  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.

  *

  * Red Hat Author(s): Behdad Esfahbod

  * Google Author(s): Behdad Esfahbod

  */

 #ifndef HB_OT_MAP_PRIVATE_HH

 #define HB_OT_MAP_PRIVATE_HH

 #include "hb-buffer-private.hh"

 struct hb_ot_shape_plan_t;

 static const hb_tag_t table_tags[2] = {HB_OT_TAG_GSUB, HB_OT_TAG_GPOS};

 struct hb_ot_map_t

 {

   friend struct hb_ot_map_builder_t;

   public:

   struct feature_map_t {

     hb_tag_t tag; /* should be first for our bsearch to work */

     unsigned int index[2]; /* GSUB/GPOS */

     unsigned int stage[2]; /* GSUB/GPOS */

     unsigned int shift;

     hb_mask_t mask;

     hb_mask_t _1_mask; /* mask for value=1, for quick access */

     unsigned int needs_fallback : 1;

     unsigned int auto_zwj : 1;

     static int cmp (const feature_map_t *a, const feature_map_t *b)

     { return a->tag < b->tag ? -1 : a->tag > b->tag ? 1 : 0; }

   };

   struct lookup_map_t {

     unsigned short index;

     unsigned short auto_zwj : 1;

     hb_mask_t mask;

     static int cmp (const lookup_map_t *a, const lookup_map_t *b)

     { return a->index < b->index ? -1 : a->index > b->index ? 1 : 0; }

   };

   typedef void (*pause_func_t) (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer);

   struct stage_map_t {

     unsigned int last_lookup; /* Cumulative */

     pause_func_t pause_func;

   };

   hb_ot_map_t (void) { memset (this, 0, sizeof (*this)); }

   inline hb_mask_t get_global_mask (void) const { return global_mask; }

   inline hb_mask_t get_mask (hb_tag_t feature_tag, unsigned int *shift = NULL) const {

     const feature_map_t *map = features.bsearch (&feature_tag);

     if (shift) *shift = map ? map->shift : 0;

     return map ? map->mask : 0;

   }

   inline bool needs_fallback (hb_tag_t feature_tag) const {

     const feature_map_t *map = features.bsearch (&feature_tag);

     return map ? map->needs_fallback : false;

   }

   inline hb_mask_t get_1_mask (hb_tag_t feature_tag) const {

     const feature_map_t *map = features.bsearch (&feature_tag);

     return map ? map->_1_mask : 0;

   }

   inline unsigned int get_feature_index (unsigned int table_index, hb_tag_t feature_tag) const {

     const feature_map_t *map = features.bsearch (&feature_tag);

     return map ? map->index[table_index] : HB_OT_LAYOUT_NO_FEATURE_INDEX;

   }

   inline unsigned int get_feature_stage (unsigned int table_index, hb_tag_t feature_tag) const {

     const feature_map_t *map = features.bsearch (&feature_tag);

     return map ? map->stage[table_index] : (unsigned int) -1;

   }

   inline void get_stage_lookups (unsigned int table_index, unsigned int stage,

 				 const struct lookup_map_t **plookups, unsigned int *lookup_count) const {

     if (unlikely (stage == (unsigned int) -1)) {

       *plookups = NULL;

       *lookup_count = 0;

       return;

     }

     assert (stage <= stages[table_index].len);

     unsigned int start = stage ? stages[table_index][stage - 1].last_lookup : 0;

     unsigned int end   = stage < stages[table_index].len ? stages[table_index][stage].last_lookup : lookups[table_index].len;

     *plookups = &lookups[table_index][start];

     *lookup_count = end - start;

   }

   HB_INTERNAL void collect_lookups (unsigned int table_index, hb_set_t *lookups) const;

   template <typename Proxy>

   HB_INTERNAL inline void apply (const Proxy &proxy,

 				 const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const;

   HB_INTERNAL void substitute (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const;

   HB_INTERNAL void position (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const;

   inline void finish (void) {

     features.finish ();

     for (unsigned int table_index = 0; table_index < 2; table_index++)

     {

       lookups[table_index].finish ();

       stages[table_index].finish ();

     }

   }

   public:

   hb_tag_t chosen_script[2];

   bool found_script[2];

   private:

   HB_INTERNAL void add_lookups (hb_face_t    *face,

 				unsigned int  table_index,

 				unsigned int  feature_index,

 				hb_mask_t     mask,

 				bool          auto_zwj);

   hb_mask_t global_mask;

   hb_prealloced_array_t<feature_map_t, 8> features;

   hb_prealloced_array_t<lookup_map_t, 32> lookups[2]; /* GSUB/GPOS */

   hb_prealloced_array_t<stage_map_t, 4> stages[2]; /* GSUB/GPOS */

 };

 enum hb_ot_map_feature_flags_t {

   F_NONE		= 0x0000,

   F_GLOBAL		= 0x0001,

   F_HAS_FALLBACK	= 0x0002,

   F_MANUAL_ZWJ		= 0x0004

 };

 /* Macro version for where const is desired. */

 #define F_COMBINE(l,r) (hb_ot_map_feature_flags_t ((unsigned int) (l) | (unsigned int) (r)))

 inline hb_ot_map_feature_flags_t

 operator | (hb_ot_map_feature_flags_t l, hb_ot_map_feature_flags_t r)

 { return hb_ot_map_feature_flags_t ((unsigned int) l | (unsigned int) r); }

 inline hb_ot_map_feature_flags_t

 operator & (hb_ot_map_feature_flags_t l, hb_ot_map_feature_flags_t r)

 { return hb_ot_map_feature_flags_t ((unsigned int) l & (unsigned int) r); }

 inline hb_ot_map_feature_flags_t

 operator ~ (hb_ot_map_feature_flags_t r)

 { return hb_ot_map_feature_flags_t (~(unsigned int) r); }

 inline hb_ot_map_feature_flags_t&

 operator |= (hb_ot_map_feature_flags_t &l, hb_ot_map_feature_flags_t r)

 { l = l | r; return l; }

 inline hb_ot_map_feature_flags_t&

 operator &= (hb_ot_map_feature_flags_t& l, hb_ot_map_feature_flags_t r)

 { l = l & r; return l; }

 struct hb_ot_map_builder_t

 {

   public:

   HB_INTERNAL hb_ot_map_builder_t (hb_face_t *face_,

 				   const hb_segment_properties_t *props_);

   HB_INTERNAL void add_feature (hb_tag_t tag, unsigned int value,

 				hb_ot_map_feature_flags_t flags);

   inline void add_global_bool_feature (hb_tag_t tag)

   { add_feature (tag, 1, F_GLOBAL); }

   inline void add_gsub_pause (hb_ot_map_t::pause_func_t pause_func)

   { add_pause (0, pause_func); }

   inline void add_gpos_pause (hb_ot_map_t::pause_func_t pause_func)

   { add_pause (1, pause_func); }

   HB_INTERNAL void compile (struct hb_ot_map_t &m);

   inline void finish (void) {

     feature_infos.finish ();

     for (unsigned int table_index = 0; table_index < 2; table_index++)

     {

       stages[table_index].finish ();

     }

   }

   private:

   struct feature_info_t {

     hb_tag_t tag;

     unsigned int seq; /* sequence#, used for stable sorting only */

     unsigned int max_value;

     hb_ot_map_feature_flags_t flags;

     unsigned int default_value; /* for non-global features, what should the unset glyphs take */

     unsigned int stage[2]; /* GSUB/GPOS */

     static int cmp (const feature_info_t *a, const feature_info_t *b)

     { return (a->tag != b->tag) ?  (a->tag < b->tag ? -1 : 1) : (a->seq < b->seq ? -1 : 1); }

   };

   struct stage_info_t {

     unsigned int index;

     hb_ot_map_t::pause_func_t pause_func;

   };

   HB_INTERNAL void add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func);

   public:

   hb_face_t *face;

   hb_segment_properties_t props;

   hb_tag_t chosen_script[2];

   bool found_script[2];

   unsigned int script_index[2], language_index[2];

   private:

   unsigned int current_stage[2]; /* GSUB/GPOS */

   hb_prealloced_array_t<feature_info_t, 32> feature_infos;

   hb_prealloced_array_t<stage_info_t, 8> stages[2]; /* GSUB/GPOS */

 };

 #endif /* HB_OT_MAP_PRIVATE_HH */