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 /*

  * Copyright © 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.

  *

  * Google Author(s): Behdad Esfahbod

  */

 #include "hb-ot-shape-complex-indic-private.hh"

 /* buffer var allocations */

 #define myanmar_category() complex_var_u8_0() /* myanmar_category_t */

 #define myanmar_position() complex_var_u8_1() /* myanmar_position_t */

 /*

  * Myanmar shaper.

  */

 static const hb_tag_t

 basic_features[] =

 {

   /*

    * Basic features.

    * These features are applied in order, one at a time, after initial_reordering.

    */

   HB_TAG('r','p','h','f'),

   HB_TAG('p','r','e','f'),

   HB_TAG('b','l','w','f'),

   HB_TAG('p','s','t','f'),

 };

 static const hb_tag_t

 other_features[] =

 {

   /*

    * Other features.

    * These features are applied all at once, after final_reordering.

    */

   HB_TAG('p','r','e','s'),

   HB_TAG('a','b','v','s'),

   HB_TAG('b','l','w','s'),

   HB_TAG('p','s','t','s'),

   /* Positioning features, though we don't care about the types. */

   HB_TAG('d','i','s','t'),

   /* Pre-release version of Windows 8 Myanmar font had abvm,blwm

    * features.  The released Windows 8 version of the font (as well

    * as the released spec) used 'mark' instead.  The Windows 8

    * shaper however didn't apply 'mark' but did apply 'mkmk'.

    * Perhaps it applied abvm/blwm.  This was fixed in a Windows 8

    * update, so now it applies mark/mkmk.  We are guessing that

    * it still applies abvm/blwm too.

    */

   HB_TAG('a','b','v','m'),

   HB_TAG('b','l','w','m'),

 };

 static void

 setup_syllables (const hb_ot_shape_plan_t *plan,

 		 hb_font_t *font,

 		 hb_buffer_t *buffer);

 static void

 initial_reordering (const hb_ot_shape_plan_t *plan,

 		    hb_font_t *font,

 		    hb_buffer_t *buffer);

 static void

 final_reordering (const hb_ot_shape_plan_t *plan,

 		  hb_font_t *font,

 		  hb_buffer_t *buffer);

 static void

 collect_features_myanmar (hb_ot_shape_planner_t *plan)

 {

   hb_ot_map_builder_t *map = &plan->map;

   /* Do this before any lookups have been applied. */

   map->add_gsub_pause (setup_syllables);

   map->add_global_bool_feature (HB_TAG('l','o','c','l'));

   /* The Indic specs do not require ccmp, but we apply it here since if

    * there is a use of it, it's typically at the beginning. */

   map->add_global_bool_feature (HB_TAG('c','c','m','p'));

   map->add_gsub_pause (initial_reordering);

   for (unsigned int i = 0; i < ARRAY_LENGTH (basic_features); i++)

   {

     map->add_feature (basic_features[i], 1, F_GLOBAL | F_MANUAL_ZWJ);

     map->add_gsub_pause (NULL);

   }

   map->add_gsub_pause (final_reordering);

   for (unsigned int i = 0; i < ARRAY_LENGTH (other_features); i++)

     map->add_feature (other_features[i], 1, F_GLOBAL | F_MANUAL_ZWJ);

 }

 static void

 override_features_myanmar (hb_ot_shape_planner_t *plan)

 {

   plan->map.add_feature (HB_TAG('l','i','g','a'), 0, F_GLOBAL);

 }

 enum syllable_type_t {

   consonant_syllable,

   punctuation_cluster,

   broken_cluster,

   non_myanmar_cluster,

 };

 #include "hb-ot-shape-complex-myanmar-machine.hh"

 /* Note: This enum is duplicated in the -machine.rl source file.

  * Not sure how to avoid duplication. */

 enum myanmar_category_t {

   OT_As  = 18, /* Asat */

   OT_D   = 19, /* Digits except zero */

   OT_D0  = 20, /* Digit zero */

   OT_DB  = OT_N, /* Dot below */

   OT_GB  = OT_DOTTEDCIRCLE,

   OT_MH  = 21, /* Various consonant medial types */

   OT_MR  = 22, /* Various consonant medial types */

   OT_MW  = 23, /* Various consonant medial types */

   OT_MY  = 24, /* Various consonant medial types */

   OT_PT  = 25, /* Pwo and other tones */

   OT_VAbv = 26,

   OT_VBlw = 27,

   OT_VPre = 28,

   OT_VPst = 29,

   OT_VS   = 30, /* Variation selectors */

   OT_P    = 31  /* Punctuation */

 };

 static inline bool

 is_one_of (const hb_glyph_info_t &info, unsigned int flags)

 {

   /* If it ligated, all bets are off. */

   if (_hb_glyph_info_ligated (&info)) return false;

   return !!(FLAG (info.myanmar_category()) & flags);

 }

 /* Note:

  *

  * We treat Vowels and placeholders as if they were consonants.  This is safe because Vowels

  * cannot happen in a consonant syllable.  The plus side however is, we can call the

  * consonant syllable logic from the vowel syllable function and get it all right! */

 #define CONSONANT_FLAGS (FLAG (OT_C) | FLAG (OT_CM) | FLAG (OT_Ra) | FLAG (OT_V) | FLAG (OT_NBSP) | FLAG (OT_GB))

 static inline bool

 is_consonant (const hb_glyph_info_t &info)

 {

   return is_one_of (info, CONSONANT_FLAGS);

 }

 static inline void

 set_myanmar_properties (hb_glyph_info_t &info)

 {

   hb_codepoint_t u = info.codepoint;

   unsigned int type = hb_indic_get_categories (u);

   indic_category_t cat = (indic_category_t) (type & 0x7F);

   indic_position_t pos = (indic_position_t) (type >> 8);

   /* Myanmar

    * http://www.microsoft.com/typography/OpenTypeDev/myanmar/intro.htm#analyze

    */

   if (unlikely (hb_in_range<hb_codepoint_t> (u, 0xFE00, 0xFE0F)))

     cat = (indic_category_t) OT_VS;

   else if (unlikely (u == 0x200C)) cat = (indic_category_t) OT_ZWNJ;

   else if (unlikely (u == 0x200D)) cat = (indic_category_t) OT_ZWJ;

   switch (u)

   {

     case 0x104E:

       cat = (indic_category_t) OT_C; /* The spec says C, IndicSyllableCategory doesn't have. */

       break;

     case 0x002D: case 0x00A0: case 0x00D7: case 0x2012:

     case 0x2013: case 0x2014: case 0x2015: case 0x2022:

     case 0x25CC: case 0x25FB: case 0x25FC: case 0x25FD:

     case 0x25FE:

       cat = (indic_category_t) OT_GB;

       break;

     case 0x1004: case 0x101B: case 0x105A:

       cat = (indic_category_t) OT_Ra;

       break;

     case 0x1032: case 0x1036:

       cat = (indic_category_t) OT_A;

       break;

     case 0x103A:

       cat = (indic_category_t) OT_As;

       break;

     case 0x1041: case 0x1042: case 0x1043: case 0x1044:

     case 0x1045: case 0x1046: case 0x1047: case 0x1048:

     case 0x1049: case 0x1090: case 0x1091: case 0x1092:

     case 0x1093: case 0x1094: case 0x1095: case 0x1096:

     case 0x1097: case 0x1098: case 0x1099:

       cat = (indic_category_t) OT_D;

       break;

     case 0x1040:

       cat = (indic_category_t) OT_D; /* XXX The spec says D0, but Uniscribe doesn't seem to do. */

       break;

     case 0x103E: case 0x1060:

       cat = (indic_category_t) OT_MH;

       break;

     case 0x103C:

       cat = (indic_category_t) OT_MR;

       break;

     case 0x103D: case 0x1082:

       cat = (indic_category_t) OT_MW;

       break;

     case 0x103B: case 0x105E: case 0x105F:

       cat = (indic_category_t) OT_MY;

       break;

     case 0x1063: case 0x1064: case 0x1069: case 0x106A:

     case 0x106B: case 0x106C: case 0x106D: case 0xAA7B:

       cat = (indic_category_t) OT_PT;

       break;

     case 0x1038: case 0x1087: case 0x1088: case 0x1089:

     case 0x108A: case 0x108B: case 0x108C: case 0x108D:

     case 0x108F: case 0x109A: case 0x109B: case 0x109C:

       cat = (indic_category_t) OT_SM;

       break;

     case 0x104A: case 0x104B:

       cat = (indic_category_t) OT_P;

       break;

   }

   if (cat == OT_M)

   {

     switch ((int) pos)

     {

       case POS_PRE_C:	cat = (indic_category_t) OT_VPre;

 			pos = POS_PRE_M;                  break;

       case POS_ABOVE_C:	cat = (indic_category_t) OT_VAbv; break;

       case POS_BELOW_C:	cat = (indic_category_t) OT_VBlw; break;

       case POS_POST_C:	cat = (indic_category_t) OT_VPst; break;

     }

   }

   info.myanmar_category() = (myanmar_category_t) cat;

   info.myanmar_position() = pos;

 }

 static void

 setup_masks_myanmar (const hb_ot_shape_plan_t *plan HB_UNUSED,

 		   hb_buffer_t              *buffer,

 		   hb_font_t                *font HB_UNUSED)

 {

   HB_BUFFER_ALLOCATE_VAR (buffer, myanmar_category);

   HB_BUFFER_ALLOCATE_VAR (buffer, myanmar_position);

   /* We cannot setup masks here.  We save information about characters

    * and setup masks later on in a pause-callback. */

   unsigned int count = buffer->len;

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

     set_myanmar_properties (buffer->info[i]);

 }

 static void

 setup_syllables (const hb_ot_shape_plan_t *plan HB_UNUSED,

 		 hb_font_t *font HB_UNUSED,

 		 hb_buffer_t *buffer)

 {

   find_syllables (buffer);

 }

 static int

 compare_myanmar_order (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb)

 {

   int a = pa->myanmar_position();

   int b = pb->myanmar_position();

   return a < b ? -1 : a == b ? 0 : +1;

 }

 /* Rules from:

  * http://www.microsoft.com/typography/OpenTypeDev/myanmar/intro.htm */

 static void

 initial_reordering_consonant_syllable (const hb_ot_shape_plan_t *plan,

 				       hb_face_t *face,

 				       hb_buffer_t *buffer,

 				       unsigned int start, unsigned int end)

 {

   hb_glyph_info_t *info = buffer->info;

   unsigned int base = end;

   bool has_reph = false;

   {

     unsigned int limit = start;

     if (start + 3 <= end &&

 	info[start  ].myanmar_category() == OT_Ra &&

 	info[start+1].myanmar_category() == OT_As &&

 	info[start+2].myanmar_category() == OT_H)

     {

       limit += 3;

       base = start;

       has_reph = true;

     }

     {

       if (!has_reph)

 	base = limit;

       for (unsigned int i = limit; i < end; i++)

 	if (is_consonant (info[i]))

 	{

 	  base = i;

 	  break;

 	}

     }

   }

   /* Reorder! */

   {

     unsigned int i = start;

     for (; i < start + (has_reph ? 3 : 0); i++)

       info[i].myanmar_position() = POS_AFTER_MAIN;

     for (; i < base; i++)

       info[i].myanmar_position() = POS_PRE_C;

     if (i < end)

     {

       info[i].myanmar_position() = POS_BASE_C;

       i++;

     }

     indic_position_t pos = POS_AFTER_MAIN;

     /* The following loop may be ugly, but it implements all of

      * Myanmar reordering! */

     for (; i < end; i++)

     {

       if (info[i].myanmar_category() == OT_MR) /* Pre-base reordering */

       {

 	info[i].myanmar_position() = POS_PRE_C;

 	continue;

       }

       if (info[i].myanmar_position() < POS_BASE_C) /* Left matra */

       {

 	continue;

       }

       if (pos == POS_AFTER_MAIN && info[i].myanmar_category() == OT_VBlw)

       {

 	pos = POS_BELOW_C;

 	info[i].myanmar_position() = pos;

 	continue;

       }

       if (pos == POS_BELOW_C && info[i].myanmar_category() == OT_A)

       {

 	info[i].myanmar_position() = POS_BEFORE_SUB;

 	continue;

       }

       if (pos == POS_BELOW_C && info[i].myanmar_category() == OT_VBlw)

       {

 	info[i].myanmar_position() = pos;

 	continue;

       }

       if (pos == POS_BELOW_C && info[i].myanmar_category() != OT_A)

       {

         pos = POS_AFTER_SUB;

 	info[i].myanmar_position() = pos;

 	continue;

       }

       info[i].myanmar_position() = pos;

     }

   }

   buffer->merge_clusters (start, end);

   /* Sit tight, rock 'n roll! */

   hb_bubble_sort (info + start, end - start, compare_myanmar_order);

 }

 static void

 initial_reordering_broken_cluster (const hb_ot_shape_plan_t *plan,

 				   hb_face_t *face,

 				   hb_buffer_t *buffer,

 				   unsigned int start, unsigned int end)

 {

   /* We already inserted dotted-circles, so just call the consonant_syllable. */

   initial_reordering_consonant_syllable (plan, face, buffer, start, end);

 }

 static void

 initial_reordering_punctuation_cluster (const hb_ot_shape_plan_t *plan HB_UNUSED,

 					hb_face_t *face HB_UNUSED,

 					hb_buffer_t *buffer HB_UNUSED,

 					unsigned int start HB_UNUSED, unsigned int end HB_UNUSED)

 {

   /* Nothing to do right now.  If we ever switch to using the output

    * buffer in the reordering process, we'd need to next_glyph() here. */

 }

 static void

 initial_reordering_non_myanmar_cluster (const hb_ot_shape_plan_t *plan HB_UNUSED,

 					hb_face_t *face HB_UNUSED,

 					hb_buffer_t *buffer HB_UNUSED,

 					unsigned int start HB_UNUSED, unsigned int end HB_UNUSED)

 {

   /* Nothing to do right now.  If we ever switch to using the output

    * buffer in the reordering process, we'd need to next_glyph() here. */

 }

 static void

 initial_reordering_syllable (const hb_ot_shape_plan_t *plan,

 			     hb_face_t *face,

 			     hb_buffer_t *buffer,

 			     unsigned int start, unsigned int end)

 {

   syllable_type_t syllable_type = (syllable_type_t) (buffer->info[start].syllable() & 0x0F);

   switch (syllable_type) {

   case consonant_syllable:	initial_reordering_consonant_syllable  (plan, face, buffer, start, end); return;

   case punctuation_cluster:	initial_reordering_punctuation_cluster (plan, face, buffer, start, end); return;

   case broken_cluster:		initial_reordering_broken_cluster      (plan, face, buffer, start, end); return;

   case non_myanmar_cluster:	initial_reordering_non_myanmar_cluster (plan, face, buffer, start, end); return;

   }

 }

 static inline void

 insert_dotted_circles (const hb_ot_shape_plan_t *plan HB_UNUSED,

 		       hb_font_t *font,

 		       hb_buffer_t *buffer)

 {

   /* Note: This loop is extra overhead, but should not be measurable. */

   bool has_broken_syllables = false;

   unsigned int count = buffer->len;

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

     if ((buffer->info[i].syllable() & 0x0F) == broken_cluster) {

       has_broken_syllables = true;

       break;

     }

   if (likely (!has_broken_syllables))

     return;

   hb_codepoint_t dottedcircle_glyph;

   if (!font->get_glyph (0x25CC, 0, &dottedcircle_glyph))

     return;

   hb_glyph_info_t dottedcircle = {0};

   dottedcircle.codepoint = 0x25CC;

   set_myanmar_properties (dottedcircle);

   dottedcircle.codepoint = dottedcircle_glyph;

   buffer->clear_output ();

   buffer->idx = 0;

   unsigned int last_syllable = 0;

   while (buffer->idx < buffer->len)

   {

     unsigned int syllable = buffer->cur().syllable();

     syllable_type_t syllable_type = (syllable_type_t) (syllable & 0x0F);

     if (unlikely (last_syllable != syllable && syllable_type == broken_cluster))

     {

       last_syllable = syllable;

       hb_glyph_info_t info = dottedcircle;

       info.cluster = buffer->cur().cluster;

       info.mask = buffer->cur().mask;

       info.syllable() = buffer->cur().syllable();

       buffer->output_info (info);

     }

     else

       buffer->next_glyph ();

   }

   buffer->swap_buffers ();

 }

 static void

 initial_reordering (const hb_ot_shape_plan_t *plan,

 		    hb_font_t *font,

 		    hb_buffer_t *buffer)

 {

   insert_dotted_circles (plan, font, buffer);

   hb_glyph_info_t *info = buffer->info;

   unsigned int count = buffer->len;

   if (unlikely (!count)) return;

   unsigned int last = 0;

   unsigned int last_syllable = info[0].syllable();

   for (unsigned int i = 1; i < count; i++)

     if (last_syllable != info[i].syllable()) {

       initial_reordering_syllable (plan, font->face, buffer, last, i);

       last = i;

       last_syllable = info[last].syllable();

     }

   initial_reordering_syllable (plan, font->face, buffer, last, count);

 }

 static void

 final_reordering (const hb_ot_shape_plan_t *plan,

 		  hb_font_t *font HB_UNUSED,

 		  hb_buffer_t *buffer)

 {

   hb_glyph_info_t *info = buffer->info;

   unsigned int count = buffer->len;

   /* Zero syllables now... */

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

     info[i].syllable() = 0;

   HB_BUFFER_DEALLOCATE_VAR (buffer, myanmar_category);

   HB_BUFFER_DEALLOCATE_VAR (buffer, myanmar_position);

 }

 const hb_ot_complex_shaper_t _hb_ot_complex_shaper_myanmar =

 {

   "myanmar",

   collect_features_myanmar,

   override_features_myanmar,

   NULL, /* data_create */

   NULL, /* data_destroy */

   NULL, /* preprocess_text */

   HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT,

   NULL, /* decompose */

   NULL, /* compose */

   setup_masks_myanmar,

   HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY,

   false, /* fallback_position */

 };