package org.apache.cassandra.io;
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 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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,
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 * KIND, either express or implied.  See the License for the
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import java.io.IOException;
import java.util.*;
import java.util.concurrent.ExecutionException;

import org.junit.Test;

import org.apache.cassandra.CleanupHelper;
import org.apache.cassandra.config.DatabaseDescriptor;
import org.apache.cassandra.db.*;
import org.apache.cassandra.db.filter.QueryPath;
import org.apache.cassandra.io.util.BufferedRandomAccessFile;
import org.apache.cassandra.io.util.FileDataInput;
import org.apache.cassandra.service.StorageService;
import org.apache.cassandra.utils.FBUtilities;

import static org.junit.Assert.assertEquals;


public class SSTableReaderTest extends CleanupHelper
{
    @Test
    public void testSpannedIndexPositions() throws IOException, ExecutionException, InterruptedException
    {
        SSTableReader.BUFFER_SIZE = 40; // each index entry is ~11 bytes, so this will generate lots of spanned entries

        Table table = Table.open("Keyspace1");
        ColumnFamilyStore store = table.getColumnFamilyStore("Standard1");

        // insert a bunch of data and compact to a single sstable
        CompactionManager.instance.disableAutoCompaction();
        for (int j = 0; j < 100; j += 2)
        {
            String key = String.valueOf(j);
            RowMutation rm = new RowMutation("Keyspace1", key);
            rm.add(new QueryPath("Standard1", null, "0".getBytes()), new byte[0], j);
            rm.apply();
        }
        store.forceBlockingFlush();
        CompactionManager.instance.submitMajor(store).get();

        // check that all our keys are found correctly
        SSTableReader sstable = store.getSSTables().iterator().next();
        for (int j = 0; j < 100; j += 2)
        {
            String key = String.valueOf(j);
            DecoratedKey dk = StorageService.getPartitioner().decorateKey(key);
            FileDataInput file = sstable.getFileDataInput(dk, DatabaseDescriptor.getIndexedReadBufferSizeInKB() * 1024);
            DecoratedKey keyInDisk = sstable.getPartitioner().convertFromDiskFormat(file.readUTF());
            assert keyInDisk.equals(dk) : String.format("%s != %s in %s", keyInDisk, dk, file.getPath());
        }

        // check no false positives
        for (int j = 1; j < 110; j += 2)
        {
            String key = String.valueOf(j);
            DecoratedKey dk = StorageService.getPartitioner().decorateKey(key);
            assert sstable.getPosition(dk) == null;
        }

        // check positionsize information
        assert sstable.indexSummary.getSpannedIndexDataPositions().entrySet().size() > 0;
        for (Map.Entry<IndexSummary.KeyPosition, SSTable.PositionSize> entry : sstable.indexSummary.getSpannedIndexDataPositions().entrySet())
        {
            IndexSummary.KeyPosition kp = entry.getKey();
            SSTable.PositionSize info = entry.getValue();

            long nextIndexPosition = kp.indexPosition + 2 + FBUtilities.encodedUTF8Length(StorageService.getPartitioner().convertToDiskFormat(kp.key)) + 8;
            BufferedRandomAccessFile indexFile = new BufferedRandomAccessFile(sstable.indexFilename(), "r");
            indexFile.seek(nextIndexPosition);
            String nextKey = indexFile.readUTF();

            BufferedRandomAccessFile file = new BufferedRandomAccessFile(sstable.getFilename(), "r");
            file.seek(info.position + info.size);
            assertEquals(nextKey, file.readUTF());
        }
    }
}