package com.browseengine.bobo.facets.filter;
import java.io.IOException;
import org.apache.lucene.search.DocIdSetIterator;
import com.browseengine.bobo.api.BoboSegmentReader;
import com.browseengine.bobo.docidset.EmptyDocIdSet;
import com.browseengine.bobo.docidset.RandomAccessDocIdSet;
import com.browseengine.bobo.facets.data.MultiValueFacetDataCache;
import com.browseengine.bobo.facets.filter.FacetFilter.FacetDocIdSetIterator;
import com.browseengine.bobo.facets.range.MultiDataCacheBuilder;
import com.browseengine.bobo.util.BigNestedIntArray;
public class MultiValueFacetFilter extends RandomAccessFilter {
private final String _val;
private final MultiDataCacheBuilder multiDataCacheBuilder;
public MultiValueFacetFilter(MultiDataCacheBuilder multiDataCacheBuilder, String val) {
this.multiDataCacheBuilder = multiDataCacheBuilder;
_val = val;
}
@Override
public double getFacetSelectivity(BoboSegmentReader reader) {
double selectivity = 0;
MultiValueFacetDataCache<?> dataCache = multiDataCacheBuilder.build(reader);
int idx = dataCache.valArray.indexOf(_val);
if (idx < 0) {
return 0.0;
}
int freq = dataCache.freqs[idx];
int total = reader.maxDoc();
selectivity = (double) freq / (double) total;
return selectivity;
}
public final static class MultiValueFacetDocIdSetIterator extends FacetDocIdSetIterator {
private final BigNestedIntArray _nestedArray;
public MultiValueFacetDocIdSetIterator(MultiValueFacetDataCache<?> dataCache, int index) {
super(dataCache, index);
_nestedArray = dataCache._nestedArray;
}
@Override
final public int nextDoc() throws IOException {
return (_doc = (_doc < _maxID ? _nestedArray.findValue(_index, (_doc + 1), _maxID)
: NO_MORE_DOCS));
}
@Override
final public int advance(int id) throws IOException {
if (_doc < id) {
return (_doc = (id <= _maxID ? _nestedArray.findValue(_index, id, _maxID) : NO_MORE_DOCS));
}
return nextDoc();
}
}
@Override
public RandomAccessDocIdSet getRandomAccessDocIdSet(BoboSegmentReader reader) throws IOException {
final MultiValueFacetDataCache<?> dataCache = multiDataCacheBuilder.build(reader);
final int index = dataCache.valArray.indexOf(_val);
final BigNestedIntArray nestedArray = dataCache._nestedArray;
if (index < 0) {
return EmptyDocIdSet.getInstance();
} else {
return new RandomAccessDocIdSet() {
@Override
public DocIdSetIterator iterator() {
return new MultiValueFacetDocIdSetIterator(dataCache, index);
}
@Override
final public boolean get(int docId) {
return nestedArray.contains(docId, index);
}
};
}
}
}