/*
 * Copyright 2016-2018 shardingsphere.io.
 * <p>
 * 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.
 * </p>
 */

package io.shardingsphere.core.executor.sql.execute.result;

import com.google.common.base.Function;
import com.google.common.collect.Iterators;
import com.google.common.collect.Lists;
import com.google.common.collect.Multimap;
import io.shardingsphere.core.merger.QueryResult;
import io.shardingsphere.core.parsing.parser.context.selectitem.AggregationDistinctSelectItem;
import io.shardingsphere.core.parsing.parser.sql.dql.select.SelectStatement;
import lombok.SneakyThrows;

import java.io.InputStream;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map.Entry;
import java.util.Set;

/**
 * Aggregation distinct query result.
 *
 * @author panjuan
 */
public final class AggregationDistinctQueryResult extends DistinctQueryResult {
    
    private final List<Integer> aggregationDistinctColumnIndexes;
    
    private final List<Integer> derivedCountIndexes;
    
    private final List<Integer> derivedSumIndexes;
    
    @SneakyThrows
    public AggregationDistinctQueryResult(final Collection<QueryResult> queryResults, final SelectStatement selectStatement) {
        super(queryResults);
        aggregationDistinctColumnIndexes = getAggregationDistinctColumnIndexes(selectStatement);
        
    }
    
    private List<Integer> getAggregationDistinctColumnIndexes(final SelectStatement selectStatement) {
        List<Integer> result = new LinkedList<>();
        for (AggregationDistinctSelectItem each :selectStatement.getAggregationDistinctSelectItems()) {
            result.add(each.getIndex());
        }
        return result;
    }
    
    private List<Integer> getDerivedCountIndexes
    
    
    
    private AggregationDistinctQueryResult(final Multimap<String, Integer> columnLabelAndIndexMap, final Iterator<List<Object>> resultData, final List<Integer> aggregationDistinctColumnIndexes) {
        super(columnLabelAndIndexMap, resultData);
        this.aggregationDistinctColumnIndexes = aggregationDistinctColumnIndexes;
    }
    
    /**
     * Divide one distinct query result to multiple child ones.
     *
     * @return multiple child distinct query results
     */
    @Override
    public List<DistinctQueryResult> divide() {
        return Lists.newArrayList(Iterators.transform(getResultData(), new Function<List<Object>, DistinctQueryResult>() {
    
            @Override
            public DistinctQueryResult apply(final List<Object> row) {
                Set<List<Object>> resultData = new LinkedHashSet<>();
                resultData.add(row);
                return new AggregationDistinctQueryResult(getColumnLabelAndIndexMap(), resultData.iterator());
            }
        }));
    }
    
    @Override
    public boolean next() {
        if (resultData.hasNext()) {
            currentRow = resultData.next();
            return true;
        }
        currentRow = null;
        return false;
    }

    @Override
    public Object getValue(final int columnIndex, final Class<?> type) {
        return currentRow.get(columnIndex - 1);
    }

    @Override
    public Object getValue(final String columnLabel, final Class<?> type) {
        return currentRow.get(getIndexByColumnLabel(columnLabel));
    }

    @Override
    public Object getCalendarValue(final int columnIndex, final Class<?> type, final Calendar calendar) {
        return currentRow.get(columnIndex - 1);
    }

    @Override
    public Object getCalendarValue(final String columnLabel, final Class<?> type, final Calendar calendar) {
        return currentRow.get(getIndexByColumnLabel(columnLabel));
    }

    @Override
    public InputStream getInputStream(final int columnIndex, final String type) {
        return (InputStream) currentRow.get(columnIndex - 1);
    }

    @Override
    public InputStream getInputStream(final String columnLabel, final String type) {
        return (InputStream) currentRow.get(getIndexByColumnLabel(columnLabel));
    }

    @Override
    public boolean wasNull() {
        return null == currentRow;
    }

    @Override
    public int getColumnCount() {
        return columnLabelAndIndexMap.size();
    }

    @Override
    public String getColumnLabel(final int columnIndex) throws SQLException {
        for (Entry<String, Integer> entry : columnLabelAndIndexMap.entries()) {
            if (columnIndex == entry.getValue()) {
                return entry.getKey();
            }
        }
        throw new SQLException("Column index out of range", "9999");
    }
    
    private Integer getIndexByColumnLabel(final String columnLabel) {
        return new ArrayList<>(columnLabelAndIndexMap.get(columnLabel)).get(0) - 1;
    }
}

@@ -1609,24 +1609,45 @@
 olumnIndexes
+ = new LinkedList%3C%3E()
 ;%0A    %0A    p
@@ -1688,24 +1688,45 @@
 CountIndexes
+ = new LinkedList%3C%3E()
 ;%0A    %0A    p
@@ -1765,24 +1765,45 @@
 edSumIndexes
+ = new LinkedList%3C%3E()
 ;%0A    %0A    @
@@ -1983,45 +1983,11 @@
     
-aggregationDistinctColumnIndexes = ge
+ini
 tAgg
@@ -2066,32 +2066,24 @@
 private 
-List%3CInteger%3E ge
+void ini
 tAggrega
@@ -2153,59 +2153,8 @@
 ) %7B%0A
-        List%3CInteger%3E result = new LinkedList%3C%3E();%0A
     
@@ -2265,22 +2265,48 @@
         
-result
+aggregationDistinctColumnIndexes
 .add(eac
@@ -2334,31 +2334,8 @@
   %7D%0A
-        return result;%0A
     
@@ -2389,16 +2389,68 @@
 tIndexes
+(final SelectStatement selectStatement) %7B%0A    %0A    %7D
 %0A    %0A  

rename to initAggregationDistinctColumnIndexes()