dali-toolkit/internal/text/emoji-helper.cpp

   1
   2 /*
   3  * Copyright (c) 2021 Samsung Electronics Co., Ltd.
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  * http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  *
  17  */
  18
  19 // FILE HEADER
  20 #include <dali-toolkit/internal/text/emoji-helper.h>
  21
  22 namespace Dali
  23 {
  24 namespace Toolkit
  25 {
  26 namespace Text
  27 {
  28 bool IsTextPresentationSequence(const TextAbstraction::Script&    currentRunScript,
  29                                 const TextAbstraction::Character& character)
  30 {
  31   return (IsSymbolOrEmojiOrTextScript(currentRunScript) && TextAbstraction::IsTextPresentationSelector(character));
  32 }
  33
  34 bool IsEmojiPresentationSequence(const TextAbstraction::Script&    currentRunScript,
  35                                  const TextAbstraction::Character& character)
  36 {
  37   return ((IsSymbolOrEmojiScript(currentRunScript) || IsEmojiColorScript(currentRunScript)) &&
  38           TextAbstraction::IsEmojiPresentationSelector(character));
  39 }
  40
  41 bool IsEmojiSequence(const TextAbstraction::Script&    currentRunScript,
  42                      const TextAbstraction::Character& character,
  43                      const TextAbstraction::Script&    characterScript)
  44 {
  45   return (IsOneOfEmojiScripts(currentRunScript) &&
  46           (IsOneOfEmojiScripts(characterScript) ||
  47            TextAbstraction::IsZeroWidthJoiner(character) ||
  48            TextAbstraction::IsZeroWidthNonJoiner(character) ||
  49            TextAbstraction::IsEmojiItem(character) ||
  50            TextAbstraction::IsMiscellaneousSymbolsAndArrowsEmoji(character) ||
  51            TextAbstraction::IsDingbatsEmoji(character)));
  52 }
  53
  54 bool IsNewSequence(const Character* const         textBuffer,
  55                    const TextAbstraction::Script& currentRunScript,
  56                    const Length&                  currentCharacterIndex,
  57                    const Length&                  lastCharacterIndex,
  58                    TextAbstraction::Script&       currentCharacterScript)
  59 {
  60   // Until now we have two cases : VariationSelector & Keycap
  61   // In-case there are more cases then should be added in this function
  62
  63   return IsNewKeycapSequence(textBuffer, currentCharacterIndex, lastCharacterIndex, currentCharacterScript) ||
  64          IsNewVariationSelectorSequence(textBuffer, currentRunScript, currentCharacterIndex, lastCharacterIndex, currentCharacterScript);
  65 }
  66
  67 //
  68
  69 bool IsNewKeycapSequence(const Character* const   textBuffer,
  70                          const Length&            currentCharacterIndex,
  71                          const Length&            lastCharacterIndex,
  72                          TextAbstraction::Script& currentCharacterScript)
  73 {
  74   // Ref: https://www.unicode.org/Public/emoji/14.0/emoji-sequences.txt Search on "Emoji_Keycap_Sequence"
  75   // Ref: https://www.unicode.org/Public/emoji/14.0/emoji-test.txt Search on "subgroup: keycap"
  76
  77   // Default initialization does not keycap sequence
  78   bool isNewKeycapSequence = false;
  79
  80   if(currentCharacterIndex < lastCharacterIndex)
  81   {
  82     Character currentCharacter = *(textBuffer + currentCharacterIndex);
  83     if(IsStartForKeycapSequence(currentCharacter))
  84     {
  85       if(!isNewKeycapSequence && currentCharacterIndex + 2 <= lastCharacterIndex)
  86       {
  87         Character characterOne = *(textBuffer + currentCharacterIndex + 1);
  88         Character characterTwo = *(textBuffer + currentCharacterIndex + 2);
  89
  90         if(TextAbstraction::IsEmojiPresentationSelector(characterOne) &&
  91            TextAbstraction::IsCombiningEnclosingKeycap(characterTwo))
  92         {
  93           isNewKeycapSequence    = true;
  94           currentCharacterScript = TextAbstraction::EMOJI_COLOR;
  95         }
  96       } // if(!isNewKeycapSequence && currentCharacterIndex + 2 <= lastCharacterIndex)
  97     }   // if(IsStartForKeycapSequence(currentCharacter))
  98   }     // if(currentCharacterIndex < lastCharacterIndex)
  99
 100   return isNewKeycapSequence;
 101 }
 102
 103 bool IsNewVariationSelectorSequence(const Character* const         textBuffer,
 104                                     const TextAbstraction::Script& currentRunScript,
 105                                     const Length&                  currentCharacterIndex,
 106                                     const Length&                  lastCharacterIndex,
 107                                     TextAbstraction::Script&       currentCharacterScript)
 108 {
 109   // Ref: Emoji and Text Presentation Selectors: https://www.unicode.org/reports/tr51/#Emoji_Variation_Selectors
 110   // Ref: Emoji Variation Sequences for UTS #51: https://www.unicode.org/Public/14.0.0/ucd/emoji/emoji-variation-sequences.txt
 111
 112   // Default initialization does not VariationSelector sequence
 113   bool isNewVariationSelectorSequence = false;
 114
 115   if(currentCharacterIndex < lastCharacterIndex)
 116   {
 117     Character currentCharacter = *(textBuffer + currentCharacterIndex);
 118     if(TextAbstraction::IsEmojiVariationSequences(currentCharacter))
 119     {
 120       if(!isNewVariationSelectorSequence && currentCharacterIndex + 1 <= lastCharacterIndex)
 121       {
 122         Character characterVS = *(textBuffer + currentCharacterIndex + 1);
 123
 124         if(TextAbstraction::IsEmojiPresentationSelector(characterVS))
 125         {
 126           isNewVariationSelectorSequence = currentRunScript != TextAbstraction::EMOJI_COLOR;
 127           currentCharacterScript         = TextAbstraction::EMOJI_COLOR;
 128         }
 129         else if(TextAbstraction::IsTextPresentationSelector(characterVS))
 130         {
 131           isNewVariationSelectorSequence = currentRunScript != TextAbstraction::EMOJI_TEXT;
 132           currentCharacterScript         = TextAbstraction::EMOJI_TEXT;
 133         }
 134
 135       } // if(!isNewVariationSelectorSequence && currentCharacterIndex + 1 <= lastCharacterIndex)
 136     }   // if(TextAbstraction::IsEmojiVariationSequences(currentCharacter))
 137   }     // if(currentCharacterIndex < lastCharacterIndex)
 138
 139   return isNewVariationSelectorSequence;
 140 }
 141
 142 bool IsStartForKeycapSequence(const TextAbstraction::Character& character)
 143 {
 144   return (TextAbstraction::IsASCIIDigits(character) ||
 145           TextAbstraction::CHAR_NUMBER_SIGN == character ||
 146           TextAbstraction::CHAR_ASTERISK == character);
 147 }
 148
 149 bool IsScriptChangedToFollowSequence(const TextAbstraction::Script&    currentRunScript,
 150                                      const TextAbstraction::Character& character,
 151                                      TextAbstraction::Script&          currentCharacterScript)
 152 {
 153   bool isUpdated = false;
 154
 155   // Keycap cases
 156   if(TextAbstraction::IsCombiningEnclosingKeycap(character))
 157   {
 158     if(TextAbstraction::EMOJI == currentRunScript)
 159     {
 160       // Keycap and unqualified
 161       // Emoji request a default presentation for an emoji character.
 162       isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI);
 163       currentCharacterScript = TextAbstraction::EMOJI;
 164     }
 165     else if(TextAbstraction::EMOJI_COLOR == currentRunScript)
 166     {
 167       // Keycap and fully-qualified
 168       // Emoji request an emoji presentation for an emoji character.
 169       isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI_COLOR);
 170       currentCharacterScript = TextAbstraction::EMOJI_COLOR;
 171     }
 172   }
 173   // Emoji(Text) Presentation cases
 174   else if(IsTextPresentationSequence(currentRunScript, character))
 175   {
 176     // Emoji request a text presentation for an emoji character.
 177     isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI_TEXT);
 178     currentCharacterScript = TextAbstraction::EMOJI_TEXT;
 179   }
 180   // Emoji(Color) Presentation cases
 181   else if(IsEmojiPresentationSequence(currentRunScript, character))
 182   {
 183     // Emoji request an emoji presentation for an emoji character.
 184     isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI_COLOR);
 185     currentCharacterScript = TextAbstraction::EMOJI_COLOR;
 186   }
 187   // Default Emoji
 188   else if(IsEmojiScript(currentRunScript) && IsEmojiScript(currentCharacterScript))
 189   {
 190     // Emoji request an emoji presentation for an emoji character.
 191     isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI);
 192     currentCharacterScript = TextAbstraction::EMOJI;
 193   }
 194   // Emoji sequences
 195   else if(IsEmojiSequence(currentRunScript, character, currentCharacterScript))
 196   {
 197     // Emoji request an emoji presentation for an emoji character.
 198     isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI_COLOR);
 199     currentCharacterScript = TextAbstraction::EMOJI_COLOR;
 200   }
 201
 202   return isUpdated;
 203 }
 204
 205 Character GetVariationSelectorByScript(const TextAbstraction::Script& script)
 206 {
 207   Character character = 0u;
 208   if(TextAbstraction::EMOJI_COLOR == script)
 209   {
 210     character = TextAbstraction::CHAR_VARIATION_SELECTOR_16;
 211   }
 212   else if(TextAbstraction::EMOJI_TEXT == script)
 213   {
 214     character = TextAbstraction::CHAR_VARIATION_SELECTOR_15;
 215   }
 216
 217   return character;
 218 }
 219
 220 } // namespace Text
 221
 222 } // namespace Toolkit
 223
 224 } // namespace Dali