Add spellcheck and word suggestion to the prediction service

third_party/android_prediction/suggest/policyimpl/dictionary/structure/v4/content/bigram_dict_content.cpp

Index: third_party/android_prediction/suggest/policyimpl/dictionary/structure/v4/content/bigram_dict_content.cpp
diff --git a/third_party/android_prediction/suggest/policyimpl/dictionary/structure/v4/content/bigram_dict_content.cpp b/third_party/android_prediction/suggest/policyimpl/dictionary/structure/v4/content/bigram_dict_content.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..ffb37919bc68b25fe034cb578a3abe91fdb536c6
--- /dev/null
+++ b/third_party/android_prediction/suggest/policyimpl/dictionary/structure/v4/content/bigram_dict_content.cpp
@@ -0,0 +1,219 @@
+/*
+ * 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.
+ */
+
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/v4/content/bigram_dict_content.h"
+
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/utils/buffer_with_extendable_buffer.h"
+
+namespace latinime {
+
+const int BigramDictContent::INVALID_LINKED_ENTRY_POS = Ver4DictConstants::NOT_A_TERMINAL_ID;
+
+const BigramEntry BigramDictContent::getBigramEntryAndAdvancePosition(
+        int *const bigramEntryPos) const {
+    const BufferWithExtendableBuffer *const bigramListBuffer = getContentBuffer();
+    const int bigramEntryTailPos = (*bigramEntryPos) + getBigramEntrySize();
+    if (*bigramEntryPos < 0 || bigramEntryTailPos > bigramListBuffer->getTailPosition()) {
+        AKLOGE("Invalid bigram entry position. bigramEntryPos: %d, bigramEntryTailPos: %d, "
+                "bufSize: %d", *bigramEntryPos, bigramEntryTailPos,
+                        bigramListBuffer->getTailPosition());
+        ASSERT(false);
+        return BigramEntry(false /* hasNext */, NOT_A_PROBABILITY,
+                Ver4DictConstants::NOT_A_TERMINAL_ID);
+    }
+    const int bigramFlags = bigramListBuffer->readUintAndAdvancePosition(
+            Ver4DictConstants::BIGRAM_FLAGS_FIELD_SIZE, bigramEntryPos);
+    const bool isLink = (bigramFlags & Ver4DictConstants::BIGRAM_IS_LINK_MASK) != 0;
+    int probability = NOT_A_PROBABILITY;
+    int timestamp = NOT_A_TIMESTAMP;
+    int level = 0;
+    int count = 0;
+    if (mHasHistoricalInfo) {
+        timestamp = bigramListBuffer->readUintAndAdvancePosition(
+                Ver4DictConstants::TIME_STAMP_FIELD_SIZE, bigramEntryPos);
+        level = bigramListBuffer->readUintAndAdvancePosition(
+                Ver4DictConstants::WORD_LEVEL_FIELD_SIZE, bigramEntryPos);
+        count = bigramListBuffer->readUintAndAdvancePosition(
+                Ver4DictConstants::WORD_COUNT_FIELD_SIZE, bigramEntryPos);
+    } else {
+        probability = bigramListBuffer->readUintAndAdvancePosition(
+                Ver4DictConstants::PROBABILITY_SIZE, bigramEntryPos);
+    }
+    const int encodedTargetTerminalId = bigramListBuffer->readUintAndAdvancePosition(
+            Ver4DictConstants::BIGRAM_TARGET_TERMINAL_ID_FIELD_SIZE, bigramEntryPos);
+    const int targetTerminalId =
+            (encodedTargetTerminalId == Ver4DictConstants::INVALID_BIGRAM_TARGET_TERMINAL_ID) ?
+                    Ver4DictConstants::NOT_A_TERMINAL_ID : encodedTargetTerminalId;
+    if (isLink) {
+        const int linkedEntryPos = targetTerminalId;
+        if (linkedEntryPos == INVALID_LINKED_ENTRY_POS) {
+            // Bigram list terminator is found.
+            return BigramEntry(false /* hasNext */, NOT_A_PROBABILITY,
+                    Ver4DictConstants::NOT_A_TERMINAL_ID);
+        }
+        *bigramEntryPos = linkedEntryPos;
+        return getBigramEntryAndAdvancePosition(bigramEntryPos);
+    }
+    // hasNext is always true because we should continue to read the next entry until the terminator
+    // is found.
+    if (mHasHistoricalInfo) {
+        const HistoricalInfo historicalInfo(timestamp, level, count);
+        return BigramEntry(true /* hasNext */, probability, &historicalInfo, targetTerminalId);
+    } else {
+        return BigramEntry(true /* hasNext */, probability, targetTerminalId);
+    }
+}
+
+bool BigramDictContent::writeBigramEntryAndAdvancePosition(
+        const BigramEntry *const bigramEntryToWrite, int *const entryWritingPos) {
+    return writeBigramEntryAttributesAndAdvancePosition(false /* isLink */,
+            bigramEntryToWrite->getProbability(), bigramEntryToWrite->getTargetTerminalId(),
+            bigramEntryToWrite->getHistoricalInfo()->getTimeStamp(),
+            bigramEntryToWrite->getHistoricalInfo()->getLevel(),
+            bigramEntryToWrite->getHistoricalInfo()->getCount(),
+            entryWritingPos);
+}
+
+bool BigramDictContent::writeBigramEntryAttributesAndAdvancePosition(
+        const bool isLink, const int probability, const int targetTerminalId,
+        const int timestamp, const int level, const int count, int *const entryWritingPos) {
+    BufferWithExtendableBuffer *const bigramListBuffer = getWritableContentBuffer();
+    const int bigramFlags = isLink ? Ver4DictConstants::BIGRAM_IS_LINK_MASK : 0;
+    if (!bigramListBuffer->writeUintAndAdvancePosition(bigramFlags,
+            Ver4DictConstants::BIGRAM_FLAGS_FIELD_SIZE, entryWritingPos)) {
+        AKLOGE("Cannot write bigram flags. pos: %d, flags: %x", *entryWritingPos, bigramFlags);
+        return false;
+    }
+    if (mHasHistoricalInfo) {
+        if (!bigramListBuffer->writeUintAndAdvancePosition(timestamp,
+                Ver4DictConstants::TIME_STAMP_FIELD_SIZE, entryWritingPos)) {
+            AKLOGE("Cannot write bigram timestamps. pos: %d, timestamp: %d", *entryWritingPos,
+                    timestamp);
+            return false;
+        }
+        if (!bigramListBuffer->writeUintAndAdvancePosition(level,
+                Ver4DictConstants::WORD_LEVEL_FIELD_SIZE, entryWritingPos)) {
+            AKLOGE("Cannot write bigram level. pos: %d, level: %d", *entryWritingPos,
+                    level);
+            return false;
+        }
+        if (!bigramListBuffer->writeUintAndAdvancePosition(count,
+                Ver4DictConstants::WORD_COUNT_FIELD_SIZE, entryWritingPos)) {
+            AKLOGE("Cannot write bigram count. pos: %d, count: %d", *entryWritingPos,
+                    count);
+            return false;
+        }
+    } else {
+        if (!bigramListBuffer->writeUintAndAdvancePosition(probability,
+                Ver4DictConstants::PROBABILITY_SIZE, entryWritingPos)) {
+            AKLOGE("Cannot write bigram probability. pos: %d, probability: %d", *entryWritingPos,
+                    probability);
+            return false;
+        }
+    }
+    const int targetTerminalIdToWrite = (targetTerminalId == Ver4DictConstants::NOT_A_TERMINAL_ID) ?
+            Ver4DictConstants::INVALID_BIGRAM_TARGET_TERMINAL_ID : targetTerminalId;
+    if (!bigramListBuffer->writeUintAndAdvancePosition(targetTerminalIdToWrite,
+            Ver4DictConstants::BIGRAM_TARGET_TERMINAL_ID_FIELD_SIZE, entryWritingPos)) {
+        AKLOGE("Cannot write bigram target terminal id. pos: %d, target terminal id: %d",
+                *entryWritingPos, targetTerminalId);
+        return false;
+    }
+    return true;
+}
+
+bool BigramDictContent::writeLink(const int linkedEntryPos, const int writingPos) {
+    const int targetTerminalId = linkedEntryPos;
+    int pos = writingPos;
+    return writeBigramEntryAttributesAndAdvancePosition(true /* isLink */,
+            NOT_A_PROBABILITY /* probability */, targetTerminalId, NOT_A_TIMESTAMP, 0 /* level */,
+            0 /* count */, &pos);
+}
+
+bool BigramDictContent::runGC(const TerminalPositionLookupTable::TerminalIdMap *const terminalIdMap,
+        const BigramDictContent *const originalBigramDictContent,
+        int *const outBigramEntryCount) {
+    for (TerminalPositionLookupTable::TerminalIdMap::const_iterator it = terminalIdMap->begin();
+            it != terminalIdMap->end(); ++it) {
+        const int originalBigramListPos =
+                originalBigramDictContent->getBigramListHeadPos(it->first);
+        if (originalBigramListPos == NOT_A_DICT_POS) {
+            // This terminal does not have a bigram list.
+            continue;
+        }
+        const int bigramListPos = getContentBuffer()->getTailPosition();
+        int bigramEntryCount = 0;
+        // Copy bigram list with GC from original content.
+        if (!runGCBigramList(originalBigramListPos, originalBigramDictContent, bigramListPos,
+                terminalIdMap, &bigramEntryCount)) {
+            AKLOGE("Cannot complete GC for the bigram list. original pos: %d, pos: %d",
+                    originalBigramListPos, bigramListPos);
+            return false;
+        }
+        if (bigramEntryCount == 0) {
+            // All bigram entries are useless. This terminal does not have a bigram list.
+            continue;
+        }
+        *outBigramEntryCount += bigramEntryCount;
+        // Set bigram list position to the lookup table.
+        if (!getUpdatableAddressLookupTable()->set(it->second, bigramListPos)) {
+            AKLOGE("Cannot set bigram list position. terminal id: %d, pos: %d",
+                    it->second, bigramListPos);
+            return false;
+        }
+    }
+    return true;
+}
+
+// Returns whether GC for the bigram list was succeeded or not.
+bool BigramDictContent::runGCBigramList(const int bigramListPos,
+        const BigramDictContent *const sourceBigramDictContent, const int toPos,
+        const TerminalPositionLookupTable::TerminalIdMap *const terminalIdMap,
+        int *const outEntryCount) {
+    bool hasNext = true;
+    int readingPos = bigramListPos;
+    int writingPos = toPos;
+    while (hasNext) {
+        const BigramEntry originalBigramEntry =
+                sourceBigramDictContent->getBigramEntryAndAdvancePosition(&readingPos);
+        hasNext = originalBigramEntry.hasNext();
+        if (!originalBigramEntry.isValid()) {
+            continue;
+        }
+        TerminalPositionLookupTable::TerminalIdMap::const_iterator it =
+                terminalIdMap->find(originalBigramEntry.getTargetTerminalId());
+        if (it == terminalIdMap->end()) {
+            // Target word has been removed.
+            continue;
+        }
+        const BigramEntry updatedBigramEntry =
+                originalBigramEntry.updateTargetTerminalIdAndGetEntry(it->second);
+        if (!writeBigramEntryAndAdvancePosition(&updatedBigramEntry, &writingPos)) {
+            AKLOGE("Cannot write bigram entry to run GC. pos: %d", writingPos);
+            return false;
+        }
+        *outEntryCount += 1;
+    }
+    if (*outEntryCount > 0) {
+        if (!writeTerminator(writingPos)) {
+            AKLOGE("Cannot write terminator to run GC. pos: %d", writingPos);
+            return false;
+        }
+    }
+    return true;
+}
+
+} // namespace latinime