Add spellcheck and word suggestion to the prediction service

third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_gc_event_listeners.cpp

Index: third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_gc_event_listeners.cpp
diff --git a/third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_gc_event_listeners.cpp b/third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_gc_event_listeners.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..ba13b800fc9f60f9345be97e534a0eca605cefae
--- /dev/null
+++ b/third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_gc_event_listeners.cpp
@@ -0,0 +1,144 @@
+/*
+ * 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/pt_common/dynamic_pt_gc_event_listeners.h"
+
+#include "third_party/android_prediction/suggest/core/policy/dictionary_header_structure_policy.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/pt_node_params.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/pt_node_writer.h"
+
+namespace latinime {
+
+bool DynamicPtGcEventListeners
+        ::TraversePolicyToUpdateUnigramProbabilityAndMarkUselessPtNodesAsDeleted
+                ::onVisitingPtNode(const PtNodeParams *const ptNodeParams) {
+    // PtNode is useless when the PtNode is not a terminal and doesn't have any not useless
+    // children.
+    bool isUselessPtNode = !ptNodeParams->isTerminal();
+    if (ptNodeParams->isTerminal() && !ptNodeParams->representsNonWordInfo()) {
+        bool needsToKeepPtNode = true;
+        if (!mPtNodeWriter->updatePtNodeProbabilityAndGetNeedsToKeepPtNodeAfterGC(
+                ptNodeParams, &needsToKeepPtNode)) {
+            AKLOGE("Cannot update PtNode probability or get needs to keep PtNode after GC.");
+            return false;
+        }
+        if (!needsToKeepPtNode) {
+            isUselessPtNode = true;
+        }
+    }
+    if (mChildrenValue > 0) {
+        isUselessPtNode = false;
+    } else if (ptNodeParams->isTerminal()) {
+        // Remove children as all children are useless.
+        if (!mPtNodeWriter->updateChildrenPosition(ptNodeParams,
+                NOT_A_DICT_POS /* newChildrenPosition */)) {
+            return false;
+        }
+    }
+    if (isUselessPtNode) {
+        // Current PtNode is no longer needed. Mark it as deleted.
+        if (!mPtNodeWriter->markPtNodeAsDeleted(ptNodeParams)) {
+            return false;
+        }
+    } else {
+        mValueStack.back() += 1;
+        if (ptNodeParams->isTerminal() && !ptNodeParams->representsNonWordInfo()) {
+            mValidUnigramCount += 1;
+        }
+    }
+    return true;
+}
+
+bool DynamicPtGcEventListeners::TraversePolicyToUpdateBigramProbability
+        ::onVisitingPtNode(const PtNodeParams *const ptNodeParams) {
+    if (!ptNodeParams->isDeleted()) {
+        int bigramEntryCount = 0;
+        if (!mPtNodeWriter->updateAllBigramEntriesAndDeleteUselessEntries(ptNodeParams,
+                &bigramEntryCount)) {
+            return false;
+        }
+        mValidBigramEntryCount += bigramEntryCount;
+    }
+    return true;
+}
+
+// Writes dummy PtNode array size when the head of PtNode array is read.
+bool DynamicPtGcEventListeners::TraversePolicyToPlaceAndWriteValidPtNodesToBuffer
+        ::onDescend(const int ptNodeArrayPos) {
+    mValidPtNodeCount = 0;
+    int writingPos = mBufferToWrite->getTailPosition();
+    mDictPositionRelocationMap->mPtNodeArrayPositionRelocationMap.insert(
+            PtNodeWriter::PtNodeArrayPositionRelocationMap::value_type(ptNodeArrayPos, writingPos));
+    // Writes dummy PtNode array size because arrays can have a forward link or needles PtNodes.
+    // This field will be updated later in onReadingPtNodeArrayTail() with actual PtNode count.
+    mPtNodeArraySizeFieldPos = writingPos;
+    return DynamicPtWritingUtils::writePtNodeArraySizeAndAdvancePosition(
+            mBufferToWrite, 0 /* arraySize */, &writingPos);
+}
+
+// Write PtNode array terminal and actual PtNode array size.
+bool DynamicPtGcEventListeners::TraversePolicyToPlaceAndWriteValidPtNodesToBuffer
+        ::onReadingPtNodeArrayTail() {
+    int writingPos = mBufferToWrite->getTailPosition();
+    // Write PtNode array terminal.
+    if (!DynamicPtWritingUtils::writeForwardLinkPositionAndAdvancePosition(
+            mBufferToWrite, NOT_A_DICT_POS /* forwardLinkPos */, &writingPos)) {
+        return false;
+    }
+    // Write actual PtNode array size.
+    if (!DynamicPtWritingUtils::writePtNodeArraySizeAndAdvancePosition(
+            mBufferToWrite, mValidPtNodeCount, &mPtNodeArraySizeFieldPos)) {
+        return false;
+    }
+    return true;
+}
+
+// Write valid PtNode to buffer and memorize mapping from the old position to the new position.
+bool DynamicPtGcEventListeners::TraversePolicyToPlaceAndWriteValidPtNodesToBuffer
+        ::onVisitingPtNode(const PtNodeParams *const ptNodeParams) {
+    if (ptNodeParams->isDeleted()) {
+        // Current PtNode is not written in new buffer because it has been deleted.
+        mDictPositionRelocationMap->mPtNodePositionRelocationMap.insert(
+                PtNodeWriter::PtNodePositionRelocationMap::value_type(
+                        ptNodeParams->getHeadPos(), NOT_A_DICT_POS));
+        return true;
+    }
+    int writingPos = mBufferToWrite->getTailPosition();
+    mDictPositionRelocationMap->mPtNodePositionRelocationMap.insert(
+            PtNodeWriter::PtNodePositionRelocationMap::value_type(
+                    ptNodeParams->getHeadPos(), writingPos));
+    mValidPtNodeCount++;
+    // Writes current PtNode.
+    return mPtNodeWriter->writePtNodeAndAdvancePosition(ptNodeParams, &writingPos);
+}
+
+bool DynamicPtGcEventListeners::TraversePolicyToUpdateAllPositionFields
+        ::onVisitingPtNode(const PtNodeParams *const ptNodeParams) {
+    // Updates parent position.
+    int bigramCount = 0;
+    if (!mPtNodeWriter->updateAllPositionFields(ptNodeParams, mDictPositionRelocationMap,
+            &bigramCount)) {
+        return false;
+    }
+    mBigramCount += bigramCount;
+    if (ptNodeParams->isTerminal()) {
+        mUnigramCount++;
+    }
+    return true;
+}
+
+} // namespace latinime