Add spellcheck and word suggestion to the prediction service

third_party/android_prediction/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_writing_helper.h

Index: third_party/android_prediction/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_writing_helper.h
diff --git a/third_party/android_prediction/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_writing_helper.h b/third_party/android_prediction/suggest/policyimpl/dictionary/structure/v4/ver4_patricia_trie_writing_helper.h
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index 0000000000000000000000000000000000000000..655e00a7daaf110492debed537bc1fde785ac4c3
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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.
+ */
+
+#ifndef LATINIME_VER4_PATRICIA_TRIE_WRITING_HELPER_H
+#define LATINIME_VER4_PATRICIA_TRIE_WRITING_HELPER_H
+
+#include "third_party/android_prediction/defines.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/pt_common/dynamic_pt_gc_event_listeners.h"
+#include "third_party/android_prediction/suggest/policyimpl/dictionary/structure/v4/content/terminal_position_lookup_table.h"
+
+namespace latinime {
+
+class HeaderPolicy;
+class Ver4DictBuffers;
+class Ver4PatriciaTrieNodeReader;
+class Ver4PatriciaTrieNodeWriter;
+
+class Ver4PatriciaTrieWritingHelper {
+ public:
+    Ver4PatriciaTrieWritingHelper(Ver4DictBuffers *const buffers)
+            : mBuffers(buffers) {}
+
+    bool writeToDictFile(const char *const dictDirPath, const int unigramCount,
+            const int bigramCount) const;
+
+    // This method cannot be const because the original dictionary buffer will be updated to detect
+    // useless PtNodes during GC.
+    bool writeToDictFileWithGC(const int rootPtNodeArrayPos, const char *const dictDirPath);
+
+ private:
+    DISALLOW_IMPLICIT_CONSTRUCTORS(Ver4PatriciaTrieWritingHelper);
+
+    class TraversePolicyToUpdateAllPtNodeFlagsAndTerminalIds
+            : public DynamicPtReadingHelper::TraversingEventListener {
+     public:
+        TraversePolicyToUpdateAllPtNodeFlagsAndTerminalIds(
+                Ver4PatriciaTrieNodeWriter *const ptNodeWriter,
+                const TerminalPositionLookupTable::TerminalIdMap *const terminalIdMap)
+                : mPtNodeWriter(ptNodeWriter), mTerminalIdMap(terminalIdMap) {}
+
+        bool onAscend() { return true; }
+
+        bool onDescend(const int ptNodeArrayPos) { return true; }
+
+        bool onReadingPtNodeArrayTail() { return true; }
+
+        bool onVisitingPtNode(const PtNodeParams *const ptNodeParams);
+
+     private:
+        DISALLOW_IMPLICIT_CONSTRUCTORS(TraversePolicyToUpdateAllPtNodeFlagsAndTerminalIds);
+
+        Ver4PatriciaTrieNodeWriter *const mPtNodeWriter;
+        const TerminalPositionLookupTable::TerminalIdMap *const mTerminalIdMap;
+    };
+
+    // For truncateUnigrams() and truncateBigrams().
+    class DictProbability {
+     public:
+        DictProbability(const int dictPos, const int probability, const int timestamp)
+                : mDictPos(dictPos), mProbability(probability), mTimestamp(timestamp) {}
+
+        int getDictPos() const {
+            return mDictPos;
+        }
+
+        int getProbability() const {
+            return mProbability;
+        }
+
+        int getTimestamp() const {
+            return mTimestamp;
+        }
+
+     private:
+        DISALLOW_DEFAULT_CONSTRUCTOR(DictProbability);
+
+        int mDictPos;
+        int mProbability;
+        int mTimestamp;
+    };
+
+    // For truncateUnigrams() and truncateBigrams().
+    class DictProbabilityComparator {
+     public:
+        bool operator()(const DictProbability &left, const DictProbability &right) {
+            if (left.getProbability() != right.getProbability()) {
+                return left.getProbability() > right.getProbability();
+            }
+            if (left.getTimestamp() != right.getTimestamp()) {
+                return left.getTimestamp() < right.getTimestamp();
+            }
+            return left.getDictPos() > right.getDictPos();
+        }
+
+     private:
+        DISALLOW_ASSIGNMENT_OPERATOR(DictProbabilityComparator);
+    };
+
+    bool runGC(const int rootPtNodeArrayPos, const HeaderPolicy *const headerPolicy,
+            Ver4DictBuffers *const buffersToWrite, int *const outUnigramCount,
+            int *const outBigramCount);
+
+    bool truncateUnigrams(const Ver4PatriciaTrieNodeReader *const ptNodeReader,
+            Ver4PatriciaTrieNodeWriter *const ptNodeWriter, const int maxUnigramCount);
+
+    bool truncateBigrams(const int maxBigramCount);
+
+    Ver4DictBuffers *const mBuffers;
+};
+} // namespace latinime
+
+#endif /* LATINIME_VER4_PATRICIA_TRIE_WRITING_HELPER_H */