/**
 *    Copyright (C) 2020-present MongoDB, Inc.
 *
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the Server Side Public License, version 1,
 *    as published by MongoDB, Inc.
 *
 *    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
 *    Server Side Public License for more details.
 *
 *    You should have received a copy of the Server Side Public License
 *    along with this program. If not, see
 *    <http://www.mongodb.com/licensing/server-side-public-license>.
 *
 *    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 Server Side 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/platform/basic.h"

#include <algorithm>

#include "mongo/db/rebuild_indexes.h"

#include "mongo/base/status.h"
#include "mongo/db/catalog/collection.h"
#include "mongo/db/catalog/index_key_validate.h"
#include "mongo/db/index/index_descriptor.h"
#include "mongo/db/index_builds_coordinator.h"

#define MONGO_LOGV2_DEFAULT_COMPONENT ::mongo::logv2::LogComponent::kStorage


namespace mongo {

StatusWith<IndexNameObjs> getIndexNameObjs(const Collection* collection,
                                           std::function<bool(const std::string&)> filter) {
    IndexNameObjs ret;
    std::vector<std::string>& indexNames = ret.first;
    std::vector<BSONObj>& indexSpecs = ret.second;
    {
        // Fetch all indexes
        collection->getAllIndexes(&indexNames);
        auto newEnd =
            std::remove_if(indexNames.begin(),
                           indexNames.end(),
                           [&filter](const std::string& indexName) { return !filter(indexName); });
        indexNames.erase(newEnd, indexNames.end());

        indexSpecs.reserve(indexNames.size());


        for (const auto& name : indexNames) {
            BSONObj spec = collection->getIndexSpec(name);
            using IndexVersion = IndexDescriptor::IndexVersion;
            IndexVersion indexVersion = IndexVersion::kV1;
            if (auto indexVersionElem = spec[IndexDescriptor::kIndexVersionFieldName]) {
                auto indexVersionNum = indexVersionElem.numberInt();
                invariant(indexVersionNum == static_cast<int>(IndexVersion::kV1) ||
                          indexVersionNum == static_cast<int>(IndexVersion::kV2));
                indexVersion = static_cast<IndexVersion>(indexVersionNum);
            }
            invariant(spec.isOwned());
            indexSpecs.push_back(spec);

            const BSONObj key = spec.getObjectField("key");
            const Status keyStatus = index_key_validate::validateKeyPattern(key, indexVersion);
            if (!keyStatus.isOK()) {
                return Status(
                    ErrorCodes::CannotCreateIndex,
                    str::stream()
                        << "Cannot rebuild index " << spec << ": " << keyStatus.reason()
                        << " For more info see http://dochub.mongodb.org/core/index-validation");
            }
        }
    }

    return ret;
}

Status rebuildIndexesOnCollection(OperationContext* opCtx,
                                  const Collection* collection,
                                  const std::vector<BSONObj>& indexSpecs,
                                  RepairData repair) {
    // Skip the rest if there are no indexes to rebuild.
    if (indexSpecs.empty())
        return Status::OK();

    // Rebuild the indexes provided by 'indexSpecs'.
    IndexBuildsCoordinator* indexBuildsCoord = IndexBuildsCoordinator::get(opCtx);
    UUID buildUUID = UUID::gen();
    auto swRebuild = indexBuildsCoord->rebuildIndexesForRecovery(
        opCtx, collection->ns(), indexSpecs, buildUUID, repair);
    if (!swRebuild.isOK()) {
        return swRebuild.getStatus();
    }

    auto [numRecords, dataSize] = swRebuild.getValue();

    auto rs = collection->getRecordStore();

    // Update the record store stats after finishing and committing the index builds.
    WriteUnitOfWork wuow(opCtx);
    rs->updateStatsAfterRepair(opCtx, numRecords, dataSize);
    wuow.commit();

    return Status::OK();
}

}  // namespace mongo