Add spellcheck and word suggestion to the prediction service

third_party/android_prediction/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_node_writer.cpp

Index: third_party/android_prediction/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_node_writer.cpp
diff --git a/third_party/android_prediction/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_node_writer.cpp b/third_party/android_prediction/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_node_writer.cpp
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index 0000000000000000000000000000000000000000..d7bae8befbc3c4d007c914efa9f8fe18290329c9
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+++ b/third_party/android_prediction/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_node_writer.cpp
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+/*
+ * Copyright (C) 2013, 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.
+ */
+
+/*
+ * !!!!! DO NOT EDIT THIS FILE !!!!!
+ *
+ * This file was generated from
+ *   suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_node_writer.cpp
+ */
+
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_node_writer.h"
+
+#include "third_party/android_prediction/suggest/core/dictionary/property/unigram_property.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/header/header_policy.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_reading_utils.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_writing_utils.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/patricia_trie_reading_utils.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/backward/v402/bigram/ver4_bigram_list_policy.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/backward/v402/content/probability_entry.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/backward/v402/shortcut/ver4_shortcut_list_policy.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/backward/v402/ver4_patricia_trie_node_reader.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/backward/v402/ver4_dict_buffers.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/utils/buffer_with_extendable_buffer.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/utils/forgetting_curve_utils.h"
+
+namespace latinime {
+namespace backward {
+namespace v402 {
+
+const int Ver4PatriciaTrieNodeWriter::CHILDREN_POSITION_FIELD_SIZE = 3;
+
+bool Ver4PatriciaTrieNodeWriter::markPtNodeAsDeleted(
+        const PtNodeParams *const toBeUpdatedPtNodeParams) {
+    int pos = toBeUpdatedPtNodeParams->getHeadPos();
+    const bool usesAdditionalBuffer = mTrieBuffer->isInAdditionalBuffer(pos);
+    const uint8_t *const dictBuf = mTrieBuffer->getBuffer(usesAdditionalBuffer);
+    if (usesAdditionalBuffer) {
+        pos -= mTrieBuffer->getOriginalBufferSize();
+    }
+    // Read original flags
+    const PatriciaTrieReadingUtils::NodeFlags originalFlags =
+            PatriciaTrieReadingUtils::getFlagsAndAdvancePosition(dictBuf, &pos);
+    const PatriciaTrieReadingUtils::NodeFlags updatedFlags =
+            DynamicPtReadingUtils::updateAndGetFlags(originalFlags, false /* isMoved */,
+                    true /* isDeleted */, false /* willBecomeNonTerminal */);
+    int writingPos = toBeUpdatedPtNodeParams->getHeadPos();
+    // Update flags.
+    if (!DynamicPtWritingUtils::writeFlagsAndAdvancePosition(mTrieBuffer, updatedFlags,
+            &writingPos)) {
+        return false;
+    }
+    if (toBeUpdatedPtNodeParams->isTerminal()) {
+        // The PtNode is a terminal. Delete entry from the terminal position lookup table.
+        return mBuffers->getMutableTerminalPositionLookupTable()->setTerminalPtNodePosition(
+                toBeUpdatedPtNodeParams->getTerminalId(), NOT_A_DICT_POS /* ptNodePos */);
+    } else {
+        return true;
+    }
+}
+
+bool Ver4PatriciaTrieNodeWriter::markPtNodeAsMoved(
+        const PtNodeParams *const toBeUpdatedPtNodeParams,
+        const int movedPos, const int bigramLinkedNodePos) {
+    int pos = toBeUpdatedPtNodeParams->getHeadPos();
+    const bool usesAdditionalBuffer = mTrieBuffer->isInAdditionalBuffer(pos);
+    const uint8_t *const dictBuf = mTrieBuffer->getBuffer(usesAdditionalBuffer);
+    if (usesAdditionalBuffer) {
+        pos -= mTrieBuffer->getOriginalBufferSize();
+    }
+    // Read original flags
+    const PatriciaTrieReadingUtils::NodeFlags originalFlags =
+            PatriciaTrieReadingUtils::getFlagsAndAdvancePosition(dictBuf, &pos);
+    const PatriciaTrieReadingUtils::NodeFlags updatedFlags =
+            DynamicPtReadingUtils::updateAndGetFlags(originalFlags, true /* isMoved */,
+                    false /* isDeleted */, false /* willBecomeNonTerminal */);
+    int writingPos = toBeUpdatedPtNodeParams->getHeadPos();
+    // Update flags.
+    if (!DynamicPtWritingUtils::writeFlagsAndAdvancePosition(mTrieBuffer, updatedFlags,
+            &writingPos)) {
+        return false;
+    }
+    // Update moved position, which is stored in the parent offset field.
+    if (!DynamicPtWritingUtils::writeParentPosOffsetAndAdvancePosition(
+            mTrieBuffer, movedPos, toBeUpdatedPtNodeParams->getHeadPos(), &writingPos)) {
+        return false;
+    }
+    if (toBeUpdatedPtNodeParams->hasChildren()) {
+        // Update children's parent position.
+        mReadingHelper.initWithPtNodeArrayPos(toBeUpdatedPtNodeParams->getChildrenPos());
+        while (!mReadingHelper.isEnd()) {
+            const PtNodeParams childPtNodeParams(mReadingHelper.getPtNodeParams());
+            int parentOffsetFieldPos = childPtNodeParams.getHeadPos()
+                    + DynamicPtWritingUtils::NODE_FLAG_FIELD_SIZE;
+            if (!DynamicPtWritingUtils::writeParentPosOffsetAndAdvancePosition(
+                    mTrieBuffer, bigramLinkedNodePos, childPtNodeParams.getHeadPos(),
+                    &parentOffsetFieldPos)) {
+                // Parent offset cannot be written because of a bug or a broken dictionary; thus,
+                // we give up to update dictionary.
+                return false;
+            }
+            mReadingHelper.readNextSiblingNode(childPtNodeParams);
+        }
+    }
+    return true;
+}
+
+bool Ver4PatriciaTrieNodeWriter::markPtNodeAsWillBecomeNonTerminal(
+        const PtNodeParams *const toBeUpdatedPtNodeParams) {
+    int pos = toBeUpdatedPtNodeParams->getHeadPos();
+    const bool usesAdditionalBuffer = mTrieBuffer->isInAdditionalBuffer(pos);
+    const uint8_t *const dictBuf = mTrieBuffer->getBuffer(usesAdditionalBuffer);
+    if (usesAdditionalBuffer) {
+        pos -= mTrieBuffer->getOriginalBufferSize();
+    }
+    // Read original flags
+    const PatriciaTrieReadingUtils::NodeFlags originalFlags =
+            PatriciaTrieReadingUtils::getFlagsAndAdvancePosition(dictBuf, &pos);
+    const PatriciaTrieReadingUtils::NodeFlags updatedFlags =
+            DynamicPtReadingUtils::updateAndGetFlags(originalFlags, false /* isMoved */,
+                    false /* isDeleted */, true /* willBecomeNonTerminal */);
+    if (!mBuffers->getMutableTerminalPositionLookupTable()->setTerminalPtNodePosition(
+            toBeUpdatedPtNodeParams->getTerminalId(), NOT_A_DICT_POS /* ptNodePos */)) {
+        AKLOGE("Cannot update terminal position lookup table. terminal id: %d",
+                toBeUpdatedPtNodeParams->getTerminalId());
+        return false;
+    }
+    // Update flags.
+    int writingPos = toBeUpdatedPtNodeParams->getHeadPos();
+    return DynamicPtWritingUtils::writeFlagsAndAdvancePosition(mTrieBuffer, updatedFlags,
+            &writingPos);
+}
+
+bool Ver4PatriciaTrieNodeWriter::updatePtNodeUnigramProperty(
+        const PtNodeParams *const toBeUpdatedPtNodeParams,
+        const UnigramProperty *const unigramProperty) {
+    // Update probability and historical information.
+    // TODO: Update other information in the unigram property.
+    if (!toBeUpdatedPtNodeParams->isTerminal()) {
+        return false;
+    }
+    const ProbabilityEntry originalProbabilityEntry =
+            mBuffers->getProbabilityDictContent()->getProbabilityEntry(
+                    toBeUpdatedPtNodeParams->getTerminalId());
+    const ProbabilityEntry probabilityEntry = createUpdatedEntryFrom(&originalProbabilityEntry,
+            unigramProperty);
+    return mBuffers->getMutableProbabilityDictContent()->setProbabilityEntry(
+            toBeUpdatedPtNodeParams->getTerminalId(), &probabilityEntry);
+}
+
+bool Ver4PatriciaTrieNodeWriter::updatePtNodeProbabilityAndGetNeedsToKeepPtNodeAfterGC(
+        const PtNodeParams *const toBeUpdatedPtNodeParams, bool *const outNeedsToKeepPtNode) {
+    if (!toBeUpdatedPtNodeParams->isTerminal()) {
+        AKLOGE("updatePtNodeProbabilityAndGetNeedsToSaveForGC is called for non-terminal PtNode.");
+        return false;
+    }
+    const ProbabilityEntry originalProbabilityEntry =
+            mBuffers->getProbabilityDictContent()->getProbabilityEntry(
+                    toBeUpdatedPtNodeParams->getTerminalId());
+    if (originalProbabilityEntry.hasHistoricalInfo()) {
+        const HistoricalInfo historicalInfo = ForgettingCurveUtils::createHistoricalInfoToSave(
+                originalProbabilityEntry.getHistoricalInfo(), mHeaderPolicy);
+        const ProbabilityEntry probabilityEntry =
+                originalProbabilityEntry.createEntryWithUpdatedHistoricalInfo(&historicalInfo);
+        if (!mBuffers->getMutableProbabilityDictContent()->setProbabilityEntry(
+                toBeUpdatedPtNodeParams->getTerminalId(), &probabilityEntry)) {
+            AKLOGE("Cannot write updated probability entry. terminalId: %d",
+                    toBeUpdatedPtNodeParams->getTerminalId());
+            return false;
+        }
+        const bool isValid = ForgettingCurveUtils::needsToKeep(&historicalInfo, mHeaderPolicy);
+        if (!isValid) {
+            if (!markPtNodeAsWillBecomeNonTerminal(toBeUpdatedPtNodeParams)) {
+                AKLOGE("Cannot mark PtNode as willBecomeNonTerminal.");
+                return false;
+            }
+        }
+        *outNeedsToKeepPtNode = isValid;
+    } else {
+        // No need to update probability.
+        *outNeedsToKeepPtNode = true;
+    }
+    return true;
+}
+
+bool Ver4PatriciaTrieNodeWriter::updateChildrenPosition(
+        const PtNodeParams *const toBeUpdatedPtNodeParams, const int newChildrenPosition) {
+    int childrenPosFieldPos = toBeUpdatedPtNodeParams->getChildrenPosFieldPos();
+    return DynamicPtWritingUtils::writeChildrenPositionAndAdvancePosition(mTrieBuffer,
+            newChildrenPosition, &childrenPosFieldPos);
+}
+
+bool Ver4PatriciaTrieNodeWriter::updateTerminalId(const PtNodeParams *const toBeUpdatedPtNodeParams,
+        const int newTerminalId) {
+    return mTrieBuffer->writeUint(newTerminalId, Ver4DictConstants::TERMINAL_ID_FIELD_SIZE,
+            toBeUpdatedPtNodeParams->getTerminalIdFieldPos());
+}
+
+bool Ver4PatriciaTrieNodeWriter::writePtNodeAndAdvancePosition(
+        const PtNodeParams *const ptNodeParams, int *const ptNodeWritingPos) {
+    return writePtNodeAndGetTerminalIdAndAdvancePosition(ptNodeParams, 0 /* outTerminalId */,
+            ptNodeWritingPos);
+}
+
+
+bool Ver4PatriciaTrieNodeWriter::writeNewTerminalPtNodeAndAdvancePosition(
+        const PtNodeParams *const ptNodeParams, const UnigramProperty *const unigramProperty,
+        int *const ptNodeWritingPos) {
+    int terminalId = Ver4DictConstants::NOT_A_TERMINAL_ID;
+    if (!writePtNodeAndGetTerminalIdAndAdvancePosition(ptNodeParams, &terminalId,
+            ptNodeWritingPos)) {
+        return false;
+    }
+    // Write probability.
+    ProbabilityEntry newProbabilityEntry;
+    const ProbabilityEntry probabilityEntryToWrite = createUpdatedEntryFrom(
+            &newProbabilityEntry, unigramProperty);
+    return mBuffers->getMutableProbabilityDictContent()->setProbabilityEntry(terminalId,
+            &probabilityEntryToWrite);
+}
+
+bool Ver4PatriciaTrieNodeWriter::addNgramEntry(const WordIdArrayView prevWordIds, const int wordId,
+        const BigramProperty *const bigramProperty, bool *const outAddedNewEntry) {
+    if (!mBigramPolicy->addNewEntry(prevWordIds[0], wordId, bigramProperty, outAddedNewEntry)) {
+        AKLOGE("Cannot add new bigram entry. terminalId: %d, targetTerminalId: %d",
+                sourcePtNodeParams->getTerminalId(), targetPtNodeParam->getTerminalId());
+        return false;
+    }
+    const int ptNodePos =
+            mBuffers->getTerminalPositionLookupTable()->getTerminalPtNodePosition(prevWordIds[0]);
+    const PtNodeParams sourcePtNodeParams =
+            mPtNodeReader->fetchPtNodeParamsInBufferFromPtNodePos(ptNodePos);
+    if (!sourcePtNodeParams.hasBigrams()) {
+        // Update has bigrams flag.
+        return updatePtNodeFlags(sourcePtNodeParams.getHeadPos(),
+                sourcePtNodeParams.isBlacklisted(), sourcePtNodeParams.isNotAWord(),
+                sourcePtNodeParams.isTerminal(), sourcePtNodeParams.hasShortcutTargets(),
+                true /* hasBigrams */,
+                sourcePtNodeParams.getCodePointCount() > 1 /* hasMultipleChars */);
+    }
+    return true;
+}
+
+bool Ver4PatriciaTrieNodeWriter::removeNgramEntry(const WordIdArrayView prevWordIds,
+        const int wordId) {
+    return mBigramPolicy->removeEntry(prevWordIds[0], wordId);
+}
+
+bool Ver4PatriciaTrieNodeWriter::updateAllBigramEntriesAndDeleteUselessEntries(
+            const PtNodeParams *const sourcePtNodeParams, int *const outBigramEntryCount) {
+    return mBigramPolicy->updateAllBigramEntriesAndDeleteUselessEntries(
+            sourcePtNodeParams->getTerminalId(), outBigramEntryCount);
+}
+
+bool Ver4PatriciaTrieNodeWriter::updateAllPositionFields(
+        const PtNodeParams *const toBeUpdatedPtNodeParams,
+        const DictPositionRelocationMap *const dictPositionRelocationMap,
+        int *const outBigramEntryCount) {
+    int parentPos = toBeUpdatedPtNodeParams->getParentPos();
+    if (parentPos != NOT_A_DICT_POS) {
+        PtNodeWriter::PtNodePositionRelocationMap::const_iterator it =
+                dictPositionRelocationMap->mPtNodePositionRelocationMap.find(parentPos);
+        if (it != dictPositionRelocationMap->mPtNodePositionRelocationMap.end()) {
+            parentPos = it->second;
+        }
+    }
+    int writingPos = toBeUpdatedPtNodeParams->getHeadPos()
+            + DynamicPtWritingUtils::NODE_FLAG_FIELD_SIZE;
+    // Write updated parent offset.
+    if (!DynamicPtWritingUtils::writeParentPosOffsetAndAdvancePosition(mTrieBuffer,
+            parentPos, toBeUpdatedPtNodeParams->getHeadPos(), &writingPos)) {
+        return false;
+    }
+
+    // Updates children position.
+    int childrenPos = toBeUpdatedPtNodeParams->getChildrenPos();
+    if (childrenPos != NOT_A_DICT_POS) {
+        PtNodeWriter::PtNodeArrayPositionRelocationMap::const_iterator it =
+                dictPositionRelocationMap->mPtNodeArrayPositionRelocationMap.find(childrenPos);
+        if (it != dictPositionRelocationMap->mPtNodeArrayPositionRelocationMap.end()) {
+            childrenPos = it->second;
+        }
+    }
+    if (!updateChildrenPosition(toBeUpdatedPtNodeParams, childrenPos)) {
+        return false;
+    }
+
+    // Counts bigram entries.
+    if (outBigramEntryCount) {
+        *outBigramEntryCount = mBigramPolicy->getBigramEntryConut(
+                toBeUpdatedPtNodeParams->getTerminalId());
+    }
+    return true;
+}
+
+bool Ver4PatriciaTrieNodeWriter::addShortcutTarget(const PtNodeParams *const ptNodeParams,
+        const int *const targetCodePoints, const int targetCodePointCount,
+        const int shortcutProbability) {
+    if (!mShortcutPolicy->addNewShortcut(ptNodeParams->getTerminalId(),
+            targetCodePoints, targetCodePointCount, shortcutProbability)) {
+        AKLOGE("Cannot add new shortuct entry. terminalId: %d", ptNodeParams->getTerminalId());
+        return false;
+    }
+    if (!ptNodeParams->hasShortcutTargets()) {
+        // Update has shortcut targets flag.
+        return updatePtNodeFlags(ptNodeParams->getHeadPos(),
+                ptNodeParams->isBlacklisted(), ptNodeParams->isNotAWord(),
+                ptNodeParams->isTerminal(), true /* hasShortcutTargets */,
+                ptNodeParams->hasBigrams(),
+                ptNodeParams->getCodePointCount() > 1 /* hasMultipleChars */);
+    }
+    return true;
+}
+
+bool Ver4PatriciaTrieNodeWriter::updatePtNodeHasBigramsAndShortcutTargetsFlags(
+        const PtNodeParams *const ptNodeParams) {
+    const bool hasBigrams = mBuffers->getBigramDictContent()->getBigramListHeadPos(
+            ptNodeParams->getTerminalId()) != NOT_A_DICT_POS;
+    const bool hasShortcutTargets = mBuffers->getShortcutDictContent()->getShortcutListHeadPos(
+            ptNodeParams->getTerminalId()) != NOT_A_DICT_POS;
+    return updatePtNodeFlags(ptNodeParams->getHeadPos(), ptNodeParams->isBlacklisted(),
+            ptNodeParams->isNotAWord(), ptNodeParams->isTerminal(), hasShortcutTargets,
+            hasBigrams, ptNodeParams->getCodePointCount() > 1 /* hasMultipleChars */);
+}
+
+bool Ver4PatriciaTrieNodeWriter::writePtNodeAndGetTerminalIdAndAdvancePosition(
+        const PtNodeParams *const ptNodeParams, int *const outTerminalId,
+        int *const ptNodeWritingPos) {
+    const int nodePos = *ptNodeWritingPos;
+    // Write dummy flags. The Node flags are updated with appropriate flags at the last step of the
+    // PtNode writing.
+    if (!DynamicPtWritingUtils::writeFlagsAndAdvancePosition(mTrieBuffer,
+            0 /* nodeFlags */, ptNodeWritingPos)) {
+        return false;
+    }
+    // Calculate a parent offset and write the offset.
+    if (!DynamicPtWritingUtils::writeParentPosOffsetAndAdvancePosition(mTrieBuffer,
+            ptNodeParams->getParentPos(), nodePos, ptNodeWritingPos)) {
+        return false;
+    }
+    // Write code points
+    if (!DynamicPtWritingUtils::writeCodePointsAndAdvancePosition(mTrieBuffer,
+            ptNodeParams->getCodePoints(), ptNodeParams->getCodePointCount(), ptNodeWritingPos)) {
+        return false;
+    }
+    int terminalId = Ver4DictConstants::NOT_A_TERMINAL_ID;
+    if (!ptNodeParams->willBecomeNonTerminal()) {
+        if (ptNodeParams->getTerminalId() != Ver4DictConstants::NOT_A_TERMINAL_ID) {
+            terminalId = ptNodeParams->getTerminalId();
+        } else if (ptNodeParams->isTerminal()) {
+            // Write terminal information using a new terminal id.
+            // Get a new unused terminal id.
+            terminalId = mBuffers->getTerminalPositionLookupTable()->getNextTerminalId();
+        }
+    }
+    const int isTerminal = terminalId != Ver4DictConstants::NOT_A_TERMINAL_ID;
+    if (isTerminal) {
+        // Update the lookup table.
+        if (!mBuffers->getMutableTerminalPositionLookupTable()->setTerminalPtNodePosition(
+                terminalId, nodePos)) {
+            return false;
+        }
+        // Write terminal Id.
+        if (!mTrieBuffer->writeUintAndAdvancePosition(terminalId,
+                Ver4DictConstants::TERMINAL_ID_FIELD_SIZE, ptNodeWritingPos)) {
+            return false;
+        }
+        if (outTerminalId) {
+            *outTerminalId = terminalId;
+        }
+    }
+    // Write children position
+    if (!DynamicPtWritingUtils::writeChildrenPositionAndAdvancePosition(mTrieBuffer,
+            ptNodeParams->getChildrenPos(), ptNodeWritingPos)) {
+        return false;
+    }
+    return updatePtNodeFlags(nodePos, ptNodeParams->isBlacklisted(), ptNodeParams->isNotAWord(),
+            isTerminal, ptNodeParams->hasShortcutTargets(), ptNodeParams->hasBigrams(),
+            ptNodeParams->getCodePointCount() > 1 /* hasMultipleChars */);
+}
+
+const ProbabilityEntry Ver4PatriciaTrieNodeWriter::createUpdatedEntryFrom(
+        const ProbabilityEntry *const originalProbabilityEntry,
+        const UnigramProperty *const unigramProperty) const {
+    // TODO: Consolidate historical info and probability.
+    if (mHeaderPolicy->hasHistoricalInfoOfWords()) {
+        const HistoricalInfo historicalInfoForUpdate(unigramProperty->getTimestamp(),
+                unigramProperty->getLevel(), unigramProperty->getCount());
+        const HistoricalInfo updatedHistoricalInfo =
+                ForgettingCurveUtils::createUpdatedHistoricalInfo(
+                        originalProbabilityEntry->getHistoricalInfo(),
+                        unigramProperty->getProbability(), &historicalInfoForUpdate, mHeaderPolicy);
+        return originalProbabilityEntry->createEntryWithUpdatedHistoricalInfo(
+                &updatedHistoricalInfo);
+    } else {
+        return originalProbabilityEntry->createEntryWithUpdatedProbability(
+                unigramProperty->getProbability());
+    }
+}
+
+bool Ver4PatriciaTrieNodeWriter::updatePtNodeFlags(const int ptNodePos,
+        const bool isBlacklisted, const bool isNotAWord, const bool isTerminal,
+        const bool hasShortcutTargets, const bool hasBigrams, const bool hasMultipleChars) {
+    // Create node flags and write them.
+    PatriciaTrieReadingUtils::NodeFlags nodeFlags =
+            PatriciaTrieReadingUtils::createAndGetFlags(isBlacklisted, isNotAWord, isTerminal,
+                    hasShortcutTargets, hasBigrams, hasMultipleChars,
+                    CHILDREN_POSITION_FIELD_SIZE);
+    if (!DynamicPtWritingUtils::writeFlags(mTrieBuffer, nodeFlags, ptNodePos)) {
+        AKLOGE("Cannot write PtNode flags. flags: %x, pos: %d", nodeFlags, ptNodePos);
+        return false;
+    }
+    return true;
+}
+
+} // namespace v402
+} // namespace backward
+} // namespace latinime