// record_store_test_repairiter.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/record_store_test_harness.h"

#include <boost/scoped_ptr.hpp>

#include "mongo/db/record_id.h"
#include "mongo/db/storage/record_data.h"
#include "mongo/db/storage/record_store.h"
#include "mongo/unittest/unittest.h"

using boost::scoped_ptr;
using std::set;
using std::string;
using std::stringstream;

namespace mongo {

    // Create an iterator for repairing an empty record store.
    TEST( RecordStoreTestHarness, GetIteratorForRepairEmpty ) {
        scoped_ptr<HarnessHelper> harnessHelper( newHarnessHelper() );
        scoped_ptr<RecordStore> rs( harnessHelper->newNonCappedRecordStore() );

        {
            scoped_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
            ASSERT_EQUALS( 0, rs->numRecords( opCtx.get() ) );
        }

        {
            scoped_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
            auto cursor = rs->getCursorForRepair( opCtx.get() );
            // returns NULL if getCursorForRepair is not supported
            if (!cursor) {
                return;
            }
            ASSERT(!cursor->next());
        }
    }

    // Insert multiple records and create an iterator for repairing the record store,
    // even though the it has not been corrupted.
    TEST( RecordStoreTestHarness, GetIteratorForRepairNonEmpty ) {
        scoped_ptr<HarnessHelper> harnessHelper( newHarnessHelper() );
        scoped_ptr<RecordStore> rs( harnessHelper->newNonCappedRecordStore() );

        {
            scoped_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
            ASSERT_EQUALS( 0, rs->numRecords( opCtx.get() ) );
        }

        const int nToInsert = 10;
        RecordId locs[nToInsert];
        for ( int i = 0; i < nToInsert; i++ ) {
            scoped_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
            {
                stringstream ss;
                ss << "record " << i;
                string data = ss.str();

                WriteUnitOfWork uow( opCtx.get() );
                StatusWith<RecordId> res = rs->insertRecord( opCtx.get(),
                                                            data.c_str(),
                                                            data.size() + 1,
                                                            false );
                ASSERT_OK( res.getStatus() );
                locs[i] = res.getValue();
                uow.commit();
            }
        }

        {
            scoped_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
            ASSERT_EQUALS( nToInsert, rs->numRecords( opCtx.get() ) );
        }

        set<RecordId> remain( locs, locs + nToInsert );
        {
            scoped_ptr<OperationContext> opCtx( harnessHelper->newOperationContext() );
            auto cursor = rs->getCursorForRepair( opCtx.get() );
            // returns NULL if getCursorForRepair is not supported
            if (!cursor) {
                return;
            }

            while (auto record = cursor->next()) {
                remain.erase(record->id); // can happen more than once per doc
            }
            ASSERT( remain.empty() );

            ASSERT(!cursor->next());
        }
    }

    // Insert a single record. Create a repair iterator pointing to that single record.
    // Then invalidate the record and ensure that the repair iterator responds correctly.
    // See SERVER-16300.
    TEST(RecordStoreTestHarness, GetIteratorForRepairInvalidateSingleton) {
        scoped_ptr<HarnessHelper> harnessHelper(newHarnessHelper());
        scoped_ptr<RecordStore> rs(harnessHelper->newNonCappedRecordStore());

        {
            scoped_ptr<OperationContext> opCtx(harnessHelper->newOperationContext());
            ASSERT_EQ(0, rs->numRecords(opCtx.get()));
        }

        // Insert one record.
        RecordId idToInvalidate;
        {
            scoped_ptr<OperationContext> opCtx(harnessHelper->newOperationContext());
            WriteUnitOfWork uow(opCtx.get());
            StatusWith<RecordId> res = rs->insertRecord(opCtx.get(), "some data", 10, false);
            ASSERT_OK(res.getStatus());
            idToInvalidate = res.getValue();
            uow.commit();
        }

        // Double-check that the record store has one record in it now.
        {
            scoped_ptr<OperationContext> opCtx(harnessHelper->newOperationContext());
            ASSERT_EQ(1, rs->numRecords(opCtx.get()));
        }

        {
            scoped_ptr<OperationContext> opCtx(harnessHelper->newOperationContext());
            auto cursor = rs->getCursorForRepair( opCtx.get() );
            // returns NULL if getCursorForRepair is not supported
            if (!cursor) {
                return;
            }

            // We should be pointing at the only record in the store.

            // Invalidate the record we're pointing at.
            cursor->savePositioned();
            cursor->invalidate(idToInvalidate);
            cursor->restore(opCtx.get());

            // Iterator should be EOF now because the only thing in the collection got deleted.
            ASSERT(!cursor->next());
        }
    }

} // namespace mongo