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 (!(TextAbstraction::IsNegativeSquaredLatinCapitalLetter(character)) &&
  46           (IsOneOfEmojiScripts(currentRunScript) &&
  47            (IsOneOfEmojiScripts(characterScript) ||
  48             TextAbstraction::IsZeroWidthJoiner(character) ||
  49             TextAbstraction::IsZeroWidthNonJoiner(character) ||
  50             TextAbstraction::IsEmojiItem(character) ||
  51             TextAbstraction::IsMiscellaneousSymbolsAndArrowsEmoji(character) ||
  52             TextAbstraction::IsDingbatsEmoji(character))));
  53 }
  54
  55 bool IsNewSequence(const Character* const         textBuffer,
  56                    const TextAbstraction::Script& currentRunScript,
  57                    const Length&                  currentCharacterIndex,
  58                    const Length&                  lastCharacterIndex,
  59                    TextAbstraction::Script&       currentCharacterScript)
  60 {
  61   // Until now we have two cases : VariationSelector & Keycap
  62   // In-case there are more cases then should be added in this function
  63
  64   return IsNewKeycapSequence(textBuffer, currentCharacterIndex, lastCharacterIndex, currentCharacterScript) ||
  65          IsNewVariationSelectorSequence(textBuffer, currentRunScript, currentCharacterIndex, lastCharacterIndex, currentCharacterScript);
  66 }
  67
  68 //
  69
  70 bool IsNewKeycapSequence(const Character* const   textBuffer,
  71                          const Length&            currentCharacterIndex,
  72                          const Length&            lastCharacterIndex,
  73                          TextAbstraction::Script& currentCharacterScript)
  74 {
  75   // Ref: https://www.unicode.org/Public/emoji/14.0/emoji-sequences.txt Search on "Emoji_Keycap_Sequence"
  76   // Ref: https://www.unicode.org/Public/emoji/14.0/emoji-test.txt Search on "subgroup: keycap"
  77
  78   // Default initialization does not keycap sequence
  79   bool isNewKeycapSequence = false;
  80
  81   if(currentCharacterIndex <= lastCharacterIndex)
  82   {
  83     Character currentCharacter = *(textBuffer + currentCharacterIndex);
  84     if(IsStartForKeycapSequence(currentCharacter))
  85     {
  86       if(!isNewKeycapSequence && currentCharacterIndex + 2 <= lastCharacterIndex)
  87       {
  88         Character characterOne = *(textBuffer + currentCharacterIndex + 1);
  89         Character characterTwo = *(textBuffer + currentCharacterIndex + 2);
  90
  91         if(TextAbstraction::IsEmojiPresentationSelector(characterOne) &&
  92            TextAbstraction::IsCombiningEnclosingKeycap(characterTwo))
  93         {
  94           isNewKeycapSequence    = true;
  95           currentCharacterScript = TextAbstraction::EMOJI_COLOR;
  96         }
  97       } // if(!isNewKeycapSequence && currentCharacterIndex + 2 <= lastCharacterIndex)
  98     }   // if(IsStartForKeycapSequence(currentCharacter))
  99   }     // if(currentCharacterIndex < lastCharacterIndex)
 100
 101   return isNewKeycapSequence;
 102 }
 103
 104 bool IsNewVariationSelectorSequence(const Character* const         textBuffer,
 105                                     const TextAbstraction::Script& currentRunScript,
 106                                     const Length&                  currentCharacterIndex,
 107                                     const Length&                  lastCharacterIndex,
 108                                     TextAbstraction::Script&       currentCharacterScript)
 109 {
 110   // Ref: Emoji and Text Presentation Selectors: https://www.unicode.org/reports/tr51/#Emoji_Variation_Selectors
 111   // Ref: Emoji Variation Sequences for UTS #51: https://www.unicode.org/Public/14.0.0/ucd/emoji/emoji-variation-sequences.txt
 112
 113   // Default initialization does not VariationSelector sequence
 114   bool isNewVariationSelectorSequence = false;
 115
 116   if(currentCharacterIndex <= lastCharacterIndex)
 117   {
 118     Character currentCharacter = *(textBuffer + currentCharacterIndex);
 119     if(TextAbstraction::IsEmojiVariationSequences(currentCharacter))
 120     {
 121       if(!isNewVariationSelectorSequence && currentCharacterIndex + 1 <= lastCharacterIndex)
 122       {
 123         Character characterVS = *(textBuffer + currentCharacterIndex + 1);
 124
 125         if(TextAbstraction::IsEmojiPresentationSelector(characterVS))
 126         {
 127           isNewVariationSelectorSequence = currentRunScript != TextAbstraction::EMOJI_COLOR;
 128           currentCharacterScript         = TextAbstraction::EMOJI_COLOR;
 129         }
 130         else if(TextAbstraction::IsTextPresentationSelector(characterVS))
 131         {
 132           isNewVariationSelectorSequence = currentRunScript != TextAbstraction::EMOJI_TEXT;
 133           currentCharacterScript         = TextAbstraction::EMOJI_TEXT;
 134         }
 135
 136       } // if(!isNewVariationSelectorSequence && currentCharacterIndex + 1 <= lastCharacterIndex)
 137     }   // if(TextAbstraction::IsEmojiVariationSequences(currentCharacter))
 138   }     // if(currentCharacterIndex < lastCharacterIndex)
 139
 140   return isNewVariationSelectorSequence;
 141 }
 142
 143 bool IsStartForKeycapSequence(const TextAbstraction::Character& character)
 144 {
 145   return (TextAbstraction::IsASCIIDigits(character) ||
 146           TextAbstraction::CHAR_NUMBER_SIGN == character ||
 147           TextAbstraction::CHAR_ASTERISK == character);
 148 }
 149
 150 bool IsScriptChangedToFollowSequence(const TextAbstraction::Script&    currentRunScript,
 151                                      const TextAbstraction::Character& character,
 152                                      TextAbstraction::Script&          currentCharacterScript)
 153 {
 154   bool isUpdated = false;
 155
 156   // Keycap cases
 157   if(TextAbstraction::IsCombiningEnclosingKeycap(character))
 158   {
 159     if(TextAbstraction::EMOJI == currentRunScript)
 160     {
 161       // Keycap and unqualified
 162       // Emoji request a default presentation for an emoji character.
 163       isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI);
 164       currentCharacterScript = TextAbstraction::EMOJI;
 165     }
 166     else if(TextAbstraction::EMOJI_COLOR == currentRunScript)
 167     {
 168       // Keycap and fully-qualified
 169       // Emoji request an emoji presentation for an emoji character.
 170       isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI_COLOR);
 171       currentCharacterScript = TextAbstraction::EMOJI_COLOR;
 172     }
 173   }
 174   // Emoji(Text) Presentation cases
 175   else if(IsTextPresentationSequence(currentRunScript, character))
 176   {
 177     // Emoji request a text presentation for an emoji character.
 178     isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI_TEXT);
 179     currentCharacterScript = TextAbstraction::EMOJI_TEXT;
 180   }
 181   // Emoji(Color) Presentation cases
 182   else if(IsEmojiPresentationSequence(currentRunScript, character))
 183   {
 184     // Emoji request an emoji presentation for an emoji character.
 185     isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI_COLOR);
 186     currentCharacterScript = TextAbstraction::EMOJI_COLOR;
 187   }
 188   // Default Emoji
 189   else if(IsEmojiScript(currentRunScript) && IsEmojiScript(currentCharacterScript))
 190   {
 191     // Emoji request an emoji presentation for an emoji character.
 192     isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI);
 193     currentCharacterScript = TextAbstraction::EMOJI;
 194   }
 195   // Emoji sequences
 196   else if(IsEmojiSequence(currentRunScript, character, currentCharacterScript))
 197   {
 198     // Emoji request an emoji presentation for an emoji character.
 199     isUpdated              = (currentCharacterScript != TextAbstraction::EMOJI_COLOR);
 200     currentCharacterScript = TextAbstraction::EMOJI_COLOR;
 201   }
 202
 203   return isUpdated;
 204 }
 205
 206 Character GetVariationSelectorByScript(const TextAbstraction::Script& script)
 207 {
 208   Character character = 0u;
 209   if(TextAbstraction::EMOJI_COLOR == script)
 210   {
 211     character = TextAbstraction::CHAR_VARIATION_SELECTOR_16;
 212   }
 213   else if(TextAbstraction::EMOJI_TEXT == script)
 214   {
 215     character = TextAbstraction::CHAR_VARIATION_SELECTOR_15;
 216   }
 217
 218   return character;
 219 }
 220
 221 } // namespace Text
 222
 223 } // namespace Toolkit
 224
 225 } // namespace Dali