LatinIME/native/jni/src/correction.h

382 lines
14 KiB
C++

/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef LATINIME_CORRECTION_H
#define LATINIME_CORRECTION_H
#include <cassert>
#include <cstring> // for memset()
#include "correction_state.h"
#include "defines.h"
#include "proximity_info_state.h"
namespace latinime {
class ProximityInfo;
class Correction {
public:
typedef enum {
TRAVERSE_ALL_ON_TERMINAL,
TRAVERSE_ALL_NOT_ON_TERMINAL,
UNRELATED,
ON_TERMINAL,
NOT_ON_TERMINAL
} CorrectionType;
Correction()
: mProximityInfo(0), mUseFullEditDistance(false), mDoAutoCompletion(false),
mMaxEditDistance(0), mMaxDepth(0), mInputSize(0), mSpaceProximityPos(0),
mMissingSpacePos(0), mTerminalInputIndex(0), mTerminalOutputIndex(0), mMaxErrors(0),
mTotalTraverseCount(0), mNeedsToTraverseAllNodes(false), mOutputIndex(0),
mInputIndex(0), mEquivalentCharCount(0), mProximityCount(0), mExcessiveCount(0),
mTransposedCount(0), mSkippedCount(0), mTransposedPos(0), mExcessivePos(0),
mSkipPos(0), mLastCharExceeded(false), mMatching(false), mProximityMatching(false),
mAdditionalProximityMatching(false), mExceeding(false), mTransposing(false),
mSkipping(false), mProximityInfoState() {
memset(mWord, 0, sizeof(mWord));
memset(mDistances, 0, sizeof(mDistances));
memset(mEditDistanceTable, 0, sizeof(mEditDistanceTable));
// NOTE: mCorrectionStates is an array of instances.
// No need to initialize it explicitly here.
}
// Non virtual inline destructor -- never inherit this class
~Correction() {}
void resetCorrection();
void initCorrection(
const ProximityInfo *pi, const int inputSize, const int maxWordLength);
void initCorrectionState(const int rootPos, const int childCount, const bool traverseAll);
// TODO: remove
void setCorrectionParams(const int skipPos, const int excessivePos, const int transposedPos,
const int spaceProximityPos, const int missingSpacePos, const bool useFullEditDistance,
const bool doAutoCompletion, const int maxErrors);
void checkState();
bool sameAsTyped();
bool initProcessState(const int index);
int getInputIndex() const;
bool needsToPrune() const;
int pushAndGetTotalTraverseCount() {
return ++mTotalTraverseCount;
}
int getFreqForSplitMultipleWords(const int *freqArray, const int *wordLengthArray,
const int wordCount, const bool isSpaceProximity, const int *word);
int getFinalProbability(const int probability, int **word, int *wordLength);
int getFinalProbabilityForSubQueue(const int probability, int **word, int *wordLength,
const int inputSize);
CorrectionType processCharAndCalcState(const int c, const bool isTerminal);
/////////////////////////
// Tree helper methods
int goDownTree(const int parentIndex, const int childCount, const int firstChildPos);
inline int getTreeSiblingPos(const int index) const {
return mCorrectionStates[index].mSiblingPos;
}
inline void setTreeSiblingPos(const int index, const int pos) {
mCorrectionStates[index].mSiblingPos = pos;
}
inline int getTreeParentIndex(const int index) const {
return mCorrectionStates[index].mParentIndex;
}
class RankingAlgorithm {
public:
static int calculateFinalProbability(const int inputIndex, const int depth,
const int probability, int *editDistanceTable, const Correction *correction,
const int inputSize);
static int calcFreqForSplitMultipleWords(const int *freqArray, const int *wordLengthArray,
const int wordCount, const Correction *correction, const bool isSpaceProximity,
const int *word);
static float calcNormalizedScore(const int *before, const int beforeLength,
const int *after, const int afterLength, const int score);
static int editDistance(const int *before, const int beforeLength, const int *after,
const int afterLength);
private:
static const int MAX_INITIAL_SCORE = 255;
};
// proximity info state
void initInputParams(const ProximityInfo *proximityInfo, const int *inputCodes,
const int inputSize, const int *xCoordinates, const int *yCoordinates) {
mProximityInfoState.initInputParams(0, MAX_POINT_TO_KEY_LENGTH,
proximityInfo, inputCodes, inputSize, xCoordinates, yCoordinates, 0, 0, false);
}
const int *getPrimaryInputWord() const {
return mProximityInfoState.getPrimaryInputWord();
}
int getPrimaryCodePointAt(const int index) const {
return mProximityInfoState.getPrimaryCodePointAt(index);
}
private:
DISALLOW_COPY_AND_ASSIGN(Correction);
/////////////////////////
// static inline utils //
/////////////////////////
static const int TWO_31ST_DIV_255 = S_INT_MAX / 255;
static inline int capped255MultForFullMatchAccentsOrCapitalizationDifference(const int num) {
return (num < TWO_31ST_DIV_255 ? 255 * num : S_INT_MAX);
}
static const int TWO_31ST_DIV_2 = S_INT_MAX / 2;
AK_FORCE_INLINE static void multiplyIntCapped(const int multiplier, int *base) {
const int temp = *base;
if (temp != S_INT_MAX) {
// Branch if multiplier == 2 for the optimization
if (multiplier < 0) {
if (DEBUG_DICT) {
assert(false);
}
AKLOGI("--- Invalid multiplier: %d", multiplier);
} else if (multiplier == 0) {
*base = 0;
} else if (multiplier == 2) {
*base = TWO_31ST_DIV_2 >= temp ? temp << 1 : S_INT_MAX;
} else {
// TODO: This overflow check gives a wrong answer when, for example,
// temp = 2^16 + 1 and multiplier = 2^17 + 1.
// Fix this behavior.
const int tempRetval = temp * multiplier;
*base = tempRetval >= temp ? tempRetval : S_INT_MAX;
}
}
}
AK_FORCE_INLINE static int powerIntCapped(const int base, const int n) {
if (n <= 0) return 1;
if (base == 2) {
return n < 31 ? 1 << n : S_INT_MAX;
} else {
int ret = base;
for (int i = 1; i < n; ++i) multiplyIntCapped(base, &ret);
return ret;
}
}
AK_FORCE_INLINE static void multiplyRate(const int rate, int *freq) {
if (*freq != S_INT_MAX) {
if (*freq > 1000000) {
*freq /= 100;
multiplyIntCapped(rate, freq);
} else {
multiplyIntCapped(rate, freq);
*freq /= 100;
}
}
}
inline int getSpaceProximityPos() const {
return mSpaceProximityPos;
}
inline int getMissingSpacePos() const {
return mMissingSpacePos;
}
inline int getSkipPos() const {
return mSkipPos;
}
inline int getExcessivePos() const {
return mExcessivePos;
}
inline int getTransposedPos() const {
return mTransposedPos;
}
inline void incrementInputIndex();
inline void incrementOutputIndex();
inline void startToTraverseAllNodes();
inline bool isSingleQuote(const int c);
inline CorrectionType processSkipChar(const int c, const bool isTerminal,
const bool inputIndexIncremented);
inline CorrectionType processUnrelatedCorrectionType();
inline void addCharToCurrentWord(const int c);
inline int getFinalProbabilityInternal(const int probability, int **word, int *wordLength,
const int inputSize);
static const int TYPED_LETTER_MULTIPLIER = 2;
static const int FULL_WORD_MULTIPLIER = 2;
const ProximityInfo *mProximityInfo;
bool mUseFullEditDistance;
bool mDoAutoCompletion;
int mMaxEditDistance;
int mMaxDepth;
int mInputSize;
int mSpaceProximityPos;
int mMissingSpacePos;
int mTerminalInputIndex;
int mTerminalOutputIndex;
int mMaxErrors;
int mTotalTraverseCount;
// The following arrays are state buffer.
int mWord[MAX_WORD_LENGTH_INTERNAL];
int mDistances[MAX_WORD_LENGTH_INTERNAL];
// Edit distance calculation requires a buffer with (N+1)^2 length for the input length N.
// Caveat: Do not create multiple tables per thread as this table eats up RAM a lot.
int mEditDistanceTable[(MAX_WORD_LENGTH_INTERNAL + 1) * (MAX_WORD_LENGTH_INTERNAL + 1)];
CorrectionState mCorrectionStates[MAX_WORD_LENGTH_INTERNAL];
// The following member variables are being used as cache values of the correction state.
bool mNeedsToTraverseAllNodes;
int mOutputIndex;
int mInputIndex;
int mEquivalentCharCount;
int mProximityCount;
int mExcessiveCount;
int mTransposedCount;
int mSkippedCount;
int mTransposedPos;
int mExcessivePos;
int mSkipPos;
bool mLastCharExceeded;
bool mMatching;
bool mProximityMatching;
bool mAdditionalProximityMatching;
bool mExceeding;
bool mTransposing;
bool mSkipping;
ProximityInfoState mProximityInfoState;
};
inline void Correction::incrementInputIndex() {
++mInputIndex;
}
AK_FORCE_INLINE void Correction::incrementOutputIndex() {
++mOutputIndex;
mCorrectionStates[mOutputIndex].mParentIndex = mCorrectionStates[mOutputIndex - 1].mParentIndex;
mCorrectionStates[mOutputIndex].mChildCount = mCorrectionStates[mOutputIndex - 1].mChildCount;
mCorrectionStates[mOutputIndex].mSiblingPos = mCorrectionStates[mOutputIndex - 1].mSiblingPos;
mCorrectionStates[mOutputIndex].mInputIndex = mInputIndex;
mCorrectionStates[mOutputIndex].mNeedsToTraverseAllNodes = mNeedsToTraverseAllNodes;
mCorrectionStates[mOutputIndex].mEquivalentCharCount = mEquivalentCharCount;
mCorrectionStates[mOutputIndex].mProximityCount = mProximityCount;
mCorrectionStates[mOutputIndex].mTransposedCount = mTransposedCount;
mCorrectionStates[mOutputIndex].mExcessiveCount = mExcessiveCount;
mCorrectionStates[mOutputIndex].mSkippedCount = mSkippedCount;
mCorrectionStates[mOutputIndex].mSkipPos = mSkipPos;
mCorrectionStates[mOutputIndex].mTransposedPos = mTransposedPos;
mCorrectionStates[mOutputIndex].mExcessivePos = mExcessivePos;
mCorrectionStates[mOutputIndex].mLastCharExceeded = mLastCharExceeded;
mCorrectionStates[mOutputIndex].mMatching = mMatching;
mCorrectionStates[mOutputIndex].mProximityMatching = mProximityMatching;
mCorrectionStates[mOutputIndex].mAdditionalProximityMatching = mAdditionalProximityMatching;
mCorrectionStates[mOutputIndex].mTransposing = mTransposing;
mCorrectionStates[mOutputIndex].mExceeding = mExceeding;
mCorrectionStates[mOutputIndex].mSkipping = mSkipping;
}
inline void Correction::startToTraverseAllNodes() {
mNeedsToTraverseAllNodes = true;
}
inline bool Correction::isSingleQuote(const int c) {
const int userTypedChar = mProximityInfoState.getPrimaryCodePointAt(mInputIndex);
return (c == KEYCODE_SINGLE_QUOTE && userTypedChar != KEYCODE_SINGLE_QUOTE);
}
AK_FORCE_INLINE Correction::CorrectionType Correction::processSkipChar(const int c,
const bool isTerminal, const bool inputIndexIncremented) {
addCharToCurrentWord(c);
mTerminalInputIndex = mInputIndex - (inputIndexIncremented ? 1 : 0);
mTerminalOutputIndex = mOutputIndex;
if (mNeedsToTraverseAllNodes && isTerminal) {
incrementOutputIndex();
return TRAVERSE_ALL_ON_TERMINAL;
} else {
incrementOutputIndex();
return TRAVERSE_ALL_NOT_ON_TERMINAL;
}
}
inline Correction::CorrectionType Correction::processUnrelatedCorrectionType() {
// Needs to set mTerminalInputIndex and mTerminalOutputIndex before returning any CorrectionType
mTerminalInputIndex = mInputIndex;
mTerminalOutputIndex = mOutputIndex;
return UNRELATED;
}
AK_FORCE_INLINE static void calcEditDistanceOneStep(int *editDistanceTable, const int *input,
const int inputSize, const int *output, const int outputLength) {
// TODO: Make sure that editDistance[0 ~ MAX_WORD_LENGTH_INTERNAL] is not touched.
// Let dp[i][j] be editDistanceTable[i * (inputSize + 1) + j].
// Assuming that dp[0][0] ... dp[outputLength - 1][inputSize] are already calculated,
// and calculate dp[ouputLength][0] ... dp[outputLength][inputSize].
int *const current = editDistanceTable + outputLength * (inputSize + 1);
const int *const prev = editDistanceTable + (outputLength - 1) * (inputSize + 1);
const int *const prevprev =
outputLength >= 2 ? editDistanceTable + (outputLength - 2) * (inputSize + 1) : 0;
current[0] = outputLength;
const int co = toBaseLowerCase(output[outputLength - 1]);
const int prevCO = outputLength >= 2 ? toBaseLowerCase(output[outputLength - 2]) : 0;
for (int i = 1; i <= inputSize; ++i) {
const int ci = toBaseLowerCase(input[i - 1]);
const int cost = (ci == co) ? 0 : 1;
current[i] = min(current[i - 1] + 1, min(prev[i] + 1, prev[i - 1] + cost));
if (i >= 2 && prevprev && ci == prevCO && co == toBaseLowerCase(input[i - 2])) {
current[i] = min(current[i], prevprev[i - 2] + 1);
}
}
}
AK_FORCE_INLINE void Correction::addCharToCurrentWord(const int c) {
mWord[mOutputIndex] = c;
const int *primaryInputWord = mProximityInfoState.getPrimaryInputWord();
calcEditDistanceOneStep(mEditDistanceTable, primaryInputWord, mInputSize, mWord,
mOutputIndex + 1);
}
inline int Correction::getFinalProbabilityInternal(const int probability, int **word,
int *wordLength, const int inputSize) {
const int outputIndex = mTerminalOutputIndex;
const int inputIndex = mTerminalInputIndex;
*wordLength = outputIndex + 1;
*word = mWord;
int finalProbability= Correction::RankingAlgorithm::calculateFinalProbability(
inputIndex, outputIndex, probability, mEditDistanceTable, this, inputSize);
return finalProbability;
}
} // namespace latinime
#endif // LATINIME_CORRECTION_H