Home | History | Annotate | Download | only in quicksearchbox
      1 /*
      2  * Copyright (C) 2010 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 package com.android.quicksearchbox;
     18 
     19 import com.android.quicksearchbox.util.CachedLater;
     20 import com.android.quicksearchbox.util.Consumer;
     21 
     22 import android.database.DataSetObserver;
     23 import android.util.Log;
     24 
     25 import java.util.ArrayList;
     26 import java.util.Collection;
     27 import java.util.Collections;
     28 import java.util.Comparator;
     29 import java.util.List;
     30 import java.util.Map;
     31 
     32 /**
     33  * A corpus ranker that uses corpus scores from the shortcut repository to rank
     34  * corpora.
     35  */
     36 public class DefaultCorpusRanker implements CorpusRanker {
     37 
     38     private static final boolean DBG = false;
     39     private static final String TAG = "QSB.DefaultCorpusRanker";
     40 
     41     private final ShortcutRepository mShortcuts;
     42 
     43     private final Corpora mCorpora;
     44 
     45     // Cached list of ranked corpora.
     46     private final RankedCorporaCache mRankedCorpora;
     47 
     48     /**
     49      * Creates a new default corpus ranker.
     50      *
     51      * @param corpora Corpora to rank.
     52      * @param shortcuts Shortcut repository for getting corpus scores.
     53      */
     54     public DefaultCorpusRanker(Corpora corpora, ShortcutRepository shortcuts) {
     55         mCorpora = corpora;
     56         mCorpora.registerDataSetObserver(new CorporaObserver());
     57         mShortcuts = shortcuts;
     58         mRankedCorpora = new RankedCorporaCache();
     59     }
     60 
     61     public void getCorporaInAll(Consumer<List<Corpus>> consumer) {
     62         mRankedCorpora.getLater(consumer);
     63     }
     64 
     65     public void clear() {
     66         mRankedCorpora.clear();
     67     }
     68 
     69     private class CorporaObserver extends DataSetObserver {
     70         @Override
     71         public void onChanged() {
     72             clear();
     73         }
     74     }
     75 
     76     private class RankedCorporaCache extends CachedLater<List<Corpus>> {
     77 
     78         @Override
     79         protected void create() {
     80             mShortcuts.getCorpusScores(new Consumer<Map<String,Integer>>(){
     81                 public boolean consume(Map<String, Integer> clickScores) {
     82                     Collection<Corpus> enabledCorpora = mCorpora.getCorporaInAll();
     83                     if (DBG) Log.d(TAG, "Ranking: " + enabledCorpora);
     84                     ArrayList<Corpus> ordered = new ArrayList<Corpus>(enabledCorpora);
     85                     Collections.sort(ordered, new CorpusComparator(clickScores));
     86 
     87                     if (DBG) Log.d(TAG, "Click scores: " + clickScores);
     88                     if (DBG) Log.d(TAG, "Ordered: " + ordered);
     89 
     90                     store(ordered);
     91                     return true;
     92                 }
     93             });
     94         }
     95 
     96     }
     97 
     98     private static class CorpusComparator implements Comparator<Corpus> {
     99         private final Map<String,Integer> mClickScores;
    100 
    101         public CorpusComparator(Map<String,Integer> clickScores) {
    102             mClickScores = clickScores;
    103         }
    104 
    105         public int compare(Corpus corpus1, Corpus corpus2) {
    106             boolean corpus1IsDefault = corpus1.isCorpusDefaultEnabled();
    107             boolean corpus2IsDefault = corpus2.isCorpusDefaultEnabled();
    108 
    109             if (corpus1IsDefault != corpus2IsDefault) {
    110                 // Default corpora always come before non-default
    111                 return corpus1IsDefault ? -1 : 1;
    112             }
    113 
    114             // Then by descending score
    115             int scoreDiff = getCorpusScore(corpus2) - getCorpusScore(corpus1);
    116             if (scoreDiff != 0) {
    117                 return scoreDiff;
    118             }
    119 
    120             // Finally by name
    121             return corpus1.getLabel().toString().compareTo(corpus2.getLabel().toString());
    122         }
    123 
    124         /**
    125          * Scores a corpus. Higher score is better.
    126          */
    127         private int getCorpusScore(Corpus corpus) {
    128             // Web corpus always comes first
    129             if (corpus.isWebCorpus()) {
    130                 return Integer.MAX_VALUE;
    131             }
    132             // Then use click score
    133             return getClickScore(corpus);
    134         }
    135 
    136         private int getClickScore(Corpus corpus) {
    137             if (mClickScores == null) return 0;
    138             Integer clickScore = mClickScores.get(corpus.getName());
    139             return clickScore == null ? 0 : clickScore;
    140         }
    141     }
    142 
    143 }
    144