// sorted_data_interface_test_spaceused.cpp

/**
 *    Copyright (C) 2014 MongoDB Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects for
 *    all of the code used other than as permitted herein. If you modify file(s)
 *    with this exception, you may extend this exception to your version of the
 *    file(s), but you are not obligated to do so. If you do not wish to do so,
 *    delete this exception statement from your version. If you delete this
 *    exception statement from all source files in the program, then also delete
 *    it in the license file.
 */

#include "mongo/db/storage/sorted_data_interface_test_harness.h"

#include <memory>

#include "mongo/db/storage/sorted_data_interface.h"
#include "mongo/unittest/unittest.h"

namespace mongo {

    // Verify that an empty index takes up no space.
    TEST( SortedDataInterface, GetSpaceUsedBytesEmpty ) {
        const std::unique_ptr<HarnessHelper> harnessHelper( newHarnessHelper() );
        const std::unique_ptr<SortedDataInterface> sorted( harnessHelper->newSortedDataInterface( false ) );

        {
            const std::unique_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
            ASSERT( sorted->isEmpty( opCtx.get() ) );
        }

        // SERVER-15416 mmapv1 test harness does not use SimpleRecordStoreV1 as its record store
        //              and HeapRecordStoreBtree::dataSize does not have an actual implementation
        // {
        //     const std::unique_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
        //     ASSERT( sorted->getSpaceUsedBytes( opCtx.get() ) == 0 );
        // }
    }

    // Verify that a nonempty index takes up some space.
    TEST( SortedDataInterface, GetSpaceUsedBytesNonEmpty ) {
        const std::unique_ptr<HarnessHelper> harnessHelper( newHarnessHelper() );
        const std::unique_ptr<SortedDataInterface> sorted( harnessHelper->newSortedDataInterface( false ) );

        {
            const std::unique_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
            ASSERT( sorted->isEmpty( opCtx.get() ) );
        }

        int nToInsert = 10;
        for ( int i = 0; i < nToInsert; i++ ) {
            const std::unique_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
            {
                WriteUnitOfWork uow( opCtx.get() );
                BSONObj key = BSON( "" << i );
                RecordId loc( 42, i * 2 );
                ASSERT_OK( sorted->insert( opCtx.get(), key, loc, true ) );
                uow.commit();
            }
        }

        {
            const std::unique_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
            ASSERT_EQUALS( nToInsert, sorted->numEntries( opCtx.get() ) );
        }

        // SERVER-15416 mmapv1 test harness does not use SimpleRecordStoreV1 as its record store
        //              and HeapRecordStoreBtree::dataSize does not have an actual implementation
        // long long spaceUsedBytes;
        // {
        //     const std::unique_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
        //     spaceUsedBytes = sorted->getSpaceUsedBytes( opCtx.get() );
        //     ASSERT( spaceUsedBytes > 0 );
        // }

        // {
        //     // getSpaceUsedBytes() returns the same value when called multiple times
        //     // and there were not interleaved write operations.
        //     const std::unique_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
        //     ASSERT_EQUALS( spaceUsedBytes, sorted->getSpaceUsedBytes( opCtx.get() ) );
        //     ASSERT_EQUALS( spaceUsedBytes, sorted->getSpaceUsedBytes( opCtx.get() ) );
        // }
    }

} // namespace mongo