grammar TR29;

ZWJ: '\u200D';
fragment VS15: '\uFE0E';
fragment VS16: '\uFE0F';
fragment NonspacingMark: [\p{Nonspacing_Mark}];
fragment TextPresentationCharacter: [\p{EmojiPresentation=TextDefault}];
fragment EmojiPresentationCharacter: [\p{EmojiPresentation=EmojiDefault}];
fragment TextPresentationSequence: EmojiPresentationCharacter VS15;
fragment EmojiPresentationSequence: TextPresentationCharacter VS16;
fragment EmojiModifierSequence:
    [\p{Grapheme_Cluster_Break=E_Base}] [\p{Grapheme_Cluster_Break=E_Modifier}];
fragment EmojiFlagSequence:
    [\p{Grapheme_Cluster_Break=Regional_Indicator}] [\p{Grapheme_Cluster_Break=Regional_Indicator}];

fragment EmojiCombiningSequence:
  (   EmojiPresentationSequence
    | TextPresentationSequence
    | EmojiPresentationCharacter )
  NonspacingMark*;
fragment EmojiCoreSequence:
    EmojiCombiningSequence
  | EmojiModifierSequence
  | EmojiFlagSequence;
fragment EmojiZWJElement:
    EmojiPresentationSequence
  | EmojiModifierSequence
  | EmojiPresentationCharacter;
fragment EmojiZWJSequence:
    EmojiZWJElement (ZWJ EmojiZWJElement)+;
EmojiSequence:
  (   EmojiZWJSequence
    | EmojiCoreSequence )
  ( Extend | ZWJ | SpacingMark )*;

Extend: [\p{Grapheme_Cluster_Break=Extend}];
SpacingMark: [\p{Grapheme_Cluster_Break=SpacingMark}];
Prepend: [\p{Grapheme_Cluster_Break=Prepend}];
NonControl: [\P{Grapheme_Cluster_Break=Control}];
CRLF: [\p{Grapheme_Cluster_Break=CR}][\p{Grapheme_Cluster_Break=LF}];
HangulSyllable:
    [\p{Grapheme_Cluster_Break=L}]* [\p{Grapheme_Cluster_Break=V}]+ [\p{Grapheme_Cluster_Break=T}]*
  | [\p{Grapheme_Cluster_Break=L}]* [\p{Grapheme_Cluster_Break=LV}] [\p{Grapheme_Cluster_Break=V}]* [\p{Grapheme_Cluster_Break=T}]*
  | [\p{Grapheme_Cluster_Break=L}]* [\p{Grapheme_Cluster_Break=LVT}] [\p{Grapheme_Cluster_Break=T}]*
  | [\p{Grapheme_Cluster_Break=L}]+
  | [\p{Grapheme_Cluster_Break=T}]+;

emoji_sequence: EmojiSequence;

grapheme_cluster:
    CRLF
  | Prepend* ( emoji_sequence | HangulSyllable | NonControl ) ( Extend | ZWJ | SpacingMark )*;

graphemes: grapheme_cluster* EOF;