/src/storage/StorageDeserializer.cpp

/*
 * Copyright (c) 2014-2015 Samsung Electronics Co., Ltd All Rights Reserved
 *
 *    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.
 */
/**
 * @file        src/storage/StorageDeserializer.cpp
 * @author      Aleksander Zdyb <a.zdyb@samsung.com>
 * @version     1.0
 * @brief       Implementation for Cynara::StorageDeserializer
 */

#include <istream>
#include <memory>
#include <string>

#include <config/PathConfig.h>
#include <exceptions/BucketDeserializationException.h>
#include <exceptions/BucketRecordCorruptedException.h>
#include <types/PolicyType.h>

#include <storage/BucketDeserializer.h>
#include <storage/Buckets.h>

#include "StorageDeserializer.h"

namespace Cynara {

StorageDeserializer::StorageDeserializer(std::shared_ptr<std::istream> inStream,
                                         BucketStreamOpener bucketStreamOpener)
        : m_inStream(inStream), m_bucketStreamOpener(bucketStreamOpener) {
}

void StorageDeserializer::initBuckets(Buckets &buckets) {
    buckets.clear();

    std::size_t lineNum = 1;
    std::string line;
    while (std::getline(*m_inStream, line, PathConfig::StoragePath::recordSeparator)) {
        if (line.empty())
            break;

        std::size_t beginToken = 0;
        auto bucketId = parseBucketId(line, beginToken);
        auto policyType = parsePolicyType(line, beginToken);
        auto metadata = parseMetadata(line, beginToken);

        //it's safe to simply insert; buckets were cleared earlier, all ids should be unique
        buckets.insert({ bucketId, PolicyBucket(bucketId, PolicyResult(policyType, metadata)) });
        ++lineNum;
    }
}

void StorageDeserializer::loadBuckets(Buckets &buckets) {
    for (auto &bucketIter : buckets) {
        const auto &bucketId = bucketIter.first;
        auto &bucket = bucketIter.second;

        auto bucketDeserializer = m_bucketStreamOpener(bucketId);
        if (bucketDeserializer != nullptr) {
            const auto policies = bucketDeserializer->loadPolicies();
            for (const auto policy : policies) {
                bucket.insertPolicy(policy);
            }
        } else {
            throw BucketDeserializationException(bucketId);
        }
    }
}

PolicyBucketId StorageDeserializer::parseBucketId(const std::string &line,
                                                    std::size_t &beginToken) {
    auto bucketNameEndToken = line.find(PathConfig::StoragePath::fieldSeparator, beginToken);
    if (bucketNameEndToken != std::string::npos) {
        auto bucketName = line.substr(beginToken, bucketNameEndToken - beginToken);
        beginToken = bucketNameEndToken + 1;
        return bucketName;
    }

    // TODO: Should throw other exception
    throw BucketRecordCorruptedException(line);
}

PolicyType StorageDeserializer::parsePolicyType(const std::string &line, std::size_t &beginToken) {
    PolicyType policyType;
    try {
        std::size_t newBegin = 0;
        policyType = std::stoi(line.substr(beginToken), &newBegin, 16);
        beginToken += newBegin;
    } catch (...) {
        throw BucketRecordCorruptedException(line);
    }

    return policyType;
}

PolicyResult::PolicyMetadata StorageDeserializer::parseMetadata(const std::string &line,
                                                                std::size_t &beginToken) {
    if (beginToken < line.size()) {
        auto ret = line.substr(beginToken + 1);
        beginToken = line.size();
        return ret;
    }

    return std::string();
}

} /* namespace Cynara */