dic_traverse_session.h revision d6fdd58cc0dcdd1e1b1018de10a30e423494a8fd 
1/*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef LATINIME_DIC_TRAVERSE_SESSION_H
18#define LATINIME_DIC_TRAVERSE_SESSION_H
19
20#include <vector>
21
22#include "defines.h"
23#include "jni.h"
24#include "suggest/core/dicnode/dic_nodes_cache.h"
25#include "suggest/core/dictionary/multi_bigram_map.h"
26#include "suggest/core/layout/proximity_info_state.h"
27
28namespace latinime {
29
30class Dictionary;
31class DictionaryStructureWithBufferPolicy;
32class ProximityInfo;
33class SuggestOptions;
34
35class DicTraverseSession {
36 public:
37
38    // A factory method for DicTraverseSession
39    static AK_FORCE_INLINE void *getSessionInstance(JNIEnv *env, jstring localeStr,
40            jlong dictSize) {
41        // To deal with the trade-off between accuracy and memory space, large cache is used for
42        // dictionaries larger that the threshold
43        return new DicTraverseSession(env, localeStr,
44                dictSize >= DICTIONARY_SIZE_THRESHOLD_TO_USE_LARGE_CACHE_FOR_SUGGESTION);
45    }
46
47    static AK_FORCE_INLINE void releaseSessionInstance(DicTraverseSession *traverseSession) {
48        delete traverseSession;
49    }
50
51    AK_FORCE_INLINE DicTraverseSession(JNIEnv *env, jstring localeStr, bool usesLargeCache)
52            : mPrevWordPtNodePos(NOT_A_DICT_POS), mProximityInfo(nullptr),
53              mDictionary(nullptr), mSuggestOptions(nullptr), mDicNodesCache(usesLargeCache),
54              mMultiBigramMap(), mInputSize(0), mMaxPointerCount(1),
55              mMultiWordCostMultiplier(1.0f) {
56        // NOTE: mProximityInfoStates is an array of instances.
57        // No need to initialize it explicitly here.
58    }
59
60    // Non virtual inline destructor -- never inherit this class
61    AK_FORCE_INLINE ~DicTraverseSession() {}
62
63    void init(const Dictionary *dictionary, const int *prevWord, int prevWordLength,
64            const SuggestOptions *const suggestOptions);
65    // TODO: Remove and merge into init
66    void setupForGetSuggestions(const ProximityInfo *pInfo, const int *inputCodePoints,
67            const int inputSize, const int *const inputXs, const int *const inputYs,
68            const int *const times, const int *const pointerIds, const float maxSpatialDistance,
69            const int maxPointerCount);
70    void resetCache(const int thresholdForNextActiveDicNodes, const int maxWords);
71
72    const DictionaryStructureWithBufferPolicy *getDictionaryStructurePolicy() const;
73
74    //--------------------
75    // getters and setters
76    //--------------------
77    const ProximityInfo *getProximityInfo() const { return mProximityInfo; }
78    const SuggestOptions *getSuggestOptions() const { return mSuggestOptions; }
79    int getPrevWordPtNodePos() const { return mPrevWordPtNodePos; }
80    DicNodesCache *getDicTraverseCache() { return &mDicNodesCache; }
81    MultiBigramMap *getMultiBigramMap() { return &mMultiBigramMap; }
82    const ProximityInfoState *getProximityInfoState(int id) const {
83        return &mProximityInfoStates[id];
84    }
85    int getInputSize() const { return mInputSize; }
86
87    bool isOnlyOnePointerUsed(int *pointerId) const {
88        // Not in the dictionary word
89        int usedPointerCount = 0;
90        int usedPointerId = 0;
91        for (int i = 0; i < mMaxPointerCount; ++i) {
92            if (mProximityInfoStates[i].isUsed()) {
93                ++usedPointerCount;
94                usedPointerId = i;
95            }
96        }
97        if (usedPointerCount != 1) {
98            return false;
99        }
100        if (pointerId) {
101            *pointerId = usedPointerId;
102        }
103        return true;
104    }
105
106    ProximityType getProximityTypeG(const DicNode *const dicNode, const int childCodePoint) const {
107        ProximityType proximityType = UNRELATED_CHAR;
108        for (int i = 0; i < MAX_POINTER_COUNT_G; ++i) {
109            if (!mProximityInfoStates[i].isUsed()) {
110                continue;
111            }
112            const int pointerId = dicNode->getInputIndex(i);
113            proximityType = mProximityInfoStates[i].getProximityTypeG(pointerId, childCodePoint);
114            ASSERT(proximityType == UNRELATED_CHAR || proximityType == MATCH_CHAR);
115            // TODO: Make this more generic
116            // Currently we assume there are only two types here -- UNRELATED_CHAR
117            // and MATCH_CHAR
118            if (proximityType != UNRELATED_CHAR) {
119                return proximityType;
120            }
121        }
122        return proximityType;
123    }
124
125    AK_FORCE_INLINE bool isCacheBorderForTyping(const int inputSize) const {
126        return mDicNodesCache.isCacheBorderForTyping(inputSize);
127    }
128
129    /**
130     * Returns whether or not it is possible to continue suggestion from the previous search.
131     */
132    // TODO: Remove. No need to check once the session is fully implemented.
133    bool isContinuousSuggestionPossible() const {
134        if (!mDicNodesCache.hasCachedDicNodesForContinuousSuggestion()) {
135            return false;
136        }
137        ASSERT(mMaxPointerCount <= MAX_POINTER_COUNT_G);
138        for (int i = 0; i < mMaxPointerCount; ++i) {
139            const ProximityInfoState *const pInfoState = getProximityInfoState(i);
140            // If a proximity info state is not continuous suggestion possible,
141            // do not continue searching.
142            if (pInfoState->isUsed() && !pInfoState->isContinuousSuggestionPossible()) {
143                return false;
144            }
145        }
146        return true;
147    }
148
149    bool isTouchPositionCorrectionEnabled() const {
150        return mProximityInfoStates[0].touchPositionCorrectionEnabled();
151    }
152
153    float getMultiWordCostMultiplier() const {
154        return mMultiWordCostMultiplier;
155    }
156
157 private:
158    DISALLOW_IMPLICIT_CONSTRUCTORS(DicTraverseSession);
159    // threshold to start caching
160    static const int CACHE_START_INPUT_LENGTH_THRESHOLD;
161    static const int DICTIONARY_SIZE_THRESHOLD_TO_USE_LARGE_CACHE_FOR_SUGGESTION;
162    void initializeProximityInfoStates(const int *const inputCodePoints, const int *const inputXs,
163            const int *const inputYs, const int *const times, const int *const pointerIds,
164            const int inputSize, const float maxSpatialDistance, const int maxPointerCount);
165
166    int mPrevWordPtNodePos;
167    const ProximityInfo *mProximityInfo;
168    const Dictionary *mDictionary;
169    const SuggestOptions *mSuggestOptions;
170
171    DicNodesCache mDicNodesCache;
172    // Temporary cache for bigram frequencies
173    MultiBigramMap mMultiBigramMap;
174    ProximityInfoState mProximityInfoStates[MAX_POINTER_COUNT_G];
175
176    int mInputSize;
177    int mMaxPointerCount;
178
179    /////////////////////////////////
180    // Configuration per dictionary
181    float mMultiWordCostMultiplier;
182
183};
184} // namespace latinime
185#endif // LATINIME_DIC_TRAVERSE_SESSION_H
186