diff options
Diffstat (limited to 'native/src/bigram_dictionary.cpp')
-rw-r--r-- | native/src/bigram_dictionary.cpp | 202 |
1 files changed, 49 insertions, 153 deletions
diff --git a/native/src/bigram_dictionary.cpp b/native/src/bigram_dictionary.cpp index 6ed4d0982..c340c6c1a 100644 --- a/native/src/bigram_dictionary.cpp +++ b/native/src/bigram_dictionary.cpp @@ -21,13 +21,14 @@ #include "bigram_dictionary.h" #include "dictionary.h" +#include "binary_format.h" namespace latinime { BigramDictionary::BigramDictionary(const unsigned char *dict, int maxWordLength, int maxAlternatives, const bool isLatestDictVersion, const bool hasBigram, Dictionary *parentDictionary) - : DICT(dict), MAX_WORD_LENGTH(maxWordLength), + : DICT(dict + NEW_DICTIONARY_HEADER_SIZE), MAX_WORD_LENGTH(maxWordLength), MAX_ALTERNATIVES(maxAlternatives), IS_LATEST_DICT_VERSION(isLatestDictVersion), HAS_BIGRAM(hasBigram), mParentDictionary(parentDictionary) { if (DEBUG_DICT) { @@ -82,169 +83,64 @@ bool BigramDictionary::addWordBigram(unsigned short *word, int length, int frequ return false; } -int BigramDictionary::getBigramAddress(int *pos, bool advance) { - int address = 0; - - address += (DICT[*pos] & 0x3F) << 16; - address += (DICT[*pos + 1] & 0xFF) << 8; - address += (DICT[*pos + 2] & 0xFF); - - if (advance) { - *pos += 3; - } - - return address; -} - -int BigramDictionary::getBigramFreq(int *pos) { - int freq = DICT[(*pos)++] & FLAG_BIGRAM_FREQ; - - return freq; -} - - +/* Parameters : + * prevWord: the word before, the one for which we need to look up bigrams. + * prevWordLength: its length. + * codes: what user typed, in the same format as for UnigramDictionary::getSuggestions. + * codesSize: the size of the codes array. + * bigramChars: an array for output, at the same format as outwords for getSuggestions. + * bigramFreq: an array to output frequencies. + * maxWordLength: the maximum size of a word. + * maxBigrams: the maximum number of bigrams fitting in the bigramChars array. + * maxAlteratives: unused. + * This method returns the number of bigrams this word has, for backward compatibility. + * Note: this is not the number of bigrams output in the array, which is the number of + * bigrams this word has WHOSE first letter also matches the letter the user typed. + * TODO: this may not be a sensible thing to do. It makes sense when the bigrams are + * used to match the first letter of the second word, but once the user has typed more + * and the bigrams are used to boost unigram result scores, it makes little sense to + * reduce their scope to the ones that match the first letter. + */ int BigramDictionary::getBigrams(unsigned short *prevWord, int prevWordLength, int *codes, int codesSize, unsigned short *bigramChars, int *bigramFreq, int maxWordLength, int maxBigrams, int maxAlternatives) { + // TODO: remove unused arguments, and refrain from storing stuff in members of this class + // TODO: have "in" arguments before "out" ones, and make out args explicit in the name mBigramFreq = bigramFreq; mBigramChars = bigramChars; mInputCodes = codes; - mInputLength = codesSize; mMaxBigrams = maxBigrams; - if (HAS_BIGRAM && IS_LATEST_DICT_VERSION) { - int pos = mParentDictionary->getBigramPosition(prevWord, prevWordLength); - if (DEBUG_DICT) { - LOGI("Pos -> %d", pos); - } - if (pos < 0) { - return 0; - } - - int bigramCount = 0; - int bigramExist = (DICT[pos] & FLAG_BIGRAM_READ); - if (bigramExist > 0) { - int nextBigramExist = 1; - while (nextBigramExist > 0 && bigramCount < maxBigrams) { - int bigramAddress = getBigramAddress(&pos, true); - int frequency = (FLAG_BIGRAM_FREQ & DICT[pos]); - // search for all bigrams and store them - searchForTerminalNode(bigramAddress, frequency); - nextBigramExist = (DICT[pos++] & FLAG_BIGRAM_CONTINUED); - bigramCount++; - } - } + const uint8_t* const root = DICT; + int pos = BinaryFormat::getTerminalPosition(root, prevWord, prevWordLength); - return bigramCount; + if (NOT_VALID_WORD == pos) return 0; + const int flags = BinaryFormat::getFlagsAndForwardPointer(root, &pos); + if (0 == (flags & UnigramDictionary::FLAG_HAS_BIGRAMS)) return 0; + if (0 == (flags & UnigramDictionary::FLAG_HAS_MULTIPLE_CHARS)) { + BinaryFormat::getCharCodeAndForwardPointer(root, &pos); + } else { + pos = BinaryFormat::skipOtherCharacters(root, pos); } - return 0; -} - -void BigramDictionary::searchForTerminalNode(int addressLookingFor, int frequency) { - // track word with such address and store it in an array - unsigned short word[MAX_WORD_LENGTH]; - - int pos; - int followDownBranchAddress = DICTIONARY_HEADER_SIZE; - bool found = false; - char followingChar = ' '; - int depth = -1; - - while(!found) { - bool followDownAddressSearchStop = false; - bool firstAddress = true; - bool haveToSearchAll = true; - - if (depth < MAX_WORD_LENGTH && depth >= 0) { - word[depth] = (unsigned short) followingChar; - } - pos = followDownBranchAddress; // pos start at count - int count = DICT[pos] & 0xFF; - if (DEBUG_DICT) { - LOGI("count - %d",count); - } - pos++; - for (int i = 0; i < count; i++) { - // pos at data - pos++; - // pos now at flag - if (!getFirstBitOfByte(&pos)) { // non-terminal - if (!followDownAddressSearchStop) { - int addr = getBigramAddress(&pos, false); - if (addr > addressLookingFor) { - followDownAddressSearchStop = true; - if (firstAddress) { - firstAddress = false; - haveToSearchAll = true; - } else if (!haveToSearchAll) { - break; - } - } else { - followDownBranchAddress = addr; - followingChar = (char)(0xFF & DICT[pos-1]); - if (firstAddress) { - firstAddress = false; - haveToSearchAll = false; - } - } - } - pos += 3; - } else if (getFirstBitOfByte(&pos)) { // terminal - if (addressLookingFor == (pos-1)) { // found !! - depth++; - word[depth] = (0xFF & DICT[pos-1]); - found = true; - break; - } - if (getSecondBitOfByte(&pos)) { // address + freq (4 byte) - if (!followDownAddressSearchStop) { - int addr = getBigramAddress(&pos, false); - if (addr > addressLookingFor) { - followDownAddressSearchStop = true; - if (firstAddress) { - firstAddress = false; - haveToSearchAll = true; - } else if (!haveToSearchAll) { - break; - } - } else { - followDownBranchAddress = addr; - followingChar = (char)(0xFF & DICT[pos-1]); - if (firstAddress) { - firstAddress = false; - haveToSearchAll = true; - } - } - } - pos += 4; - } else { // freq only (2 byte) - pos += 2; - } - - // skipping bigram - int bigramExist = (DICT[pos] & FLAG_BIGRAM_READ); - if (bigramExist > 0) { - int nextBigramExist = 1; - while (nextBigramExist > 0) { - pos += 3; - nextBigramExist = (DICT[pos++] & FLAG_BIGRAM_CONTINUED); - } - } else { - pos++; - } - } + pos = BinaryFormat::skipChildrenPosition(flags, pos); + pos = BinaryFormat::skipFrequency(flags, pos); + int bigramFlags; + int bigramCount = 0; + do { + bigramFlags = BinaryFormat::getFlagsAndForwardPointer(root, &pos); + uint16_t bigramBuffer[MAX_WORD_LENGTH]; + const int bigramPos = BinaryFormat::getAttributeAddressAndForwardPointer(root, bigramFlags, + &pos); + const int length = BinaryFormat::getWordAtAddress(root, bigramPos, MAX_WORD_LENGTH, + bigramBuffer); + + if (checkFirstCharacter(bigramBuffer)) { + const int frequency = UnigramDictionary::MASK_ATTRIBUTE_FREQUENCY & bigramFlags; + addWordBigram(bigramBuffer, length, frequency); } - depth++; - if (followDownBranchAddress == 0) { - if (DEBUG_DICT) { - LOGI("ERROR!!! Cannot find bigram!!"); - } - break; - } - } - if (checkFirstCharacter(word)) { - addWordBigram(word, depth, frequency); - } + ++bigramCount; + } while (0 != (UnigramDictionary::FLAG_ATTRIBUTE_HAS_NEXT & bigramFlags)); + return bigramCount; } bool BigramDictionary::checkFirstCharacter(unsigned short *word) { |