/**
 * Copyright © 2019 IBM Corporation
 *
 * 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.
 */
#include "manager.hpp"

#include "additional_data.hpp"
#include "json_utils.hpp"
#include "pel.hpp"

#include <sys/inotify.h>
#include <unistd.h>

#include <filesystem>
#include <fstream>
#include <xyz/openbmc_project/Common/error.hpp>
#include <xyz/openbmc_project/Logging/Create/server.hpp>

namespace openpower
{
namespace pels
{

using namespace phosphor::logging;
namespace fs = std::filesystem;
namespace rg = openpower::pels::message;

namespace common_error = sdbusplus::xyz::openbmc_project::Common::Error;

using Create = sdbusplus::xyz::openbmc_project::Logging::server::Create;

namespace additional_data
{
constexpr auto rawPEL = "RAWPEL";
constexpr auto esel = "ESEL";
} // namespace additional_data

Manager::~Manager()
{
    if (_pelFileDeleteFD != -1)
    {
        if (_pelFileDeleteWatchFD != -1)
        {
            inotify_rm_watch(_pelFileDeleteFD, _pelFileDeleteWatchFD);
        }
        close(_pelFileDeleteFD);
    }
}

void Manager::create(const std::string& message, uint32_t obmcLogID,
                     uint64_t timestamp, Entry::Level severity,
                     const std::vector<std::string>& additionalData,
                     const std::vector<std::string>& associations,
                     const FFDCEntries& ffdc)
{
    AdditionalData ad{additionalData};

    // If a PEL was passed in via a filename or in an ESEL,
    // use that.  Otherwise, create one.
    auto rawPelPath = ad.getValue(additional_data::rawPEL);
    if (rawPelPath)
    {
        addRawPEL(*rawPelPath, obmcLogID);
    }
    else
    {
        auto esel = ad.getValue(additional_data::esel);
        if (esel)
        {
            addESELPEL(*esel, obmcLogID);
        }
        else
        {
            createPEL(message, obmcLogID, timestamp, severity, additionalData,
                      associations, ffdc);
        }
    }
}

void Manager::addRawPEL(const std::string& rawPelPath, uint32_t obmcLogID)
{
    if (fs::exists(rawPelPath))
    {
        std::ifstream file(rawPelPath, std::ios::in | std::ios::binary);

        auto data = std::vector<uint8_t>(std::istreambuf_iterator<char>(file),
                                         std::istreambuf_iterator<char>());
        if (file.fail())
        {
            log<level::ERR>("Filesystem error reading a raw PEL",
                            entry("PELFILE=%s", rawPelPath.c_str()),
                            entry("OBMCLOGID=%d", obmcLogID));
            // TODO, Decide what to do here. Maybe nothing.
            return;
        }

        file.close();

        addPEL(data, obmcLogID);
    }
    else
    {
        log<level::ERR>("Raw PEL file from BMC event log does not exist",
                        entry("PELFILE=%s", (rawPelPath).c_str()),
                        entry("OBMCLOGID=%d", obmcLogID));
    }
}

void Manager::addPEL(std::vector<uint8_t>& pelData, uint32_t obmcLogID)
{

    auto pel = std::make_unique<openpower::pels::PEL>(pelData, obmcLogID);
    if (pel->valid())
    {
        // PELs created by others still need these fields set by us.
        pel->assignID();
        pel->setCommitTime();

        try
        {
            log<level::DEBUG>("Adding external PEL to repo",
                              entry("PEL_ID=0x%X", pel->id()));

            _repo.add(pel);

            if (_repo.sizeWarning())
            {
                scheduleRepoPrune();
            }
        }
        catch (std::exception& e)
        {
            // Probably a full or r/o filesystem, not much we can do.
            log<level::ERR>("Unable to add PEL to Repository",
                            entry("PEL_ID=0x%X", pel->id()));
        }
    }
    else
    {
        log<level::ERR>("Invalid PEL received from the host",
                        entry("OBMCLOGID=%d", obmcLogID));

        AdditionalData ad;
        ad.add("PLID", getNumberString("0x%08X", pel->plid()));
        ad.add("OBMC_LOG_ID", std::to_string(obmcLogID));
        ad.add("PEL_SIZE", std::to_string(pelData.size()));

        std::string asciiString;
        auto src = pel->primarySRC();
        if (src)
        {
            asciiString = (*src)->asciiString();
        }

        ad.add("SRC", asciiString);

        _eventLogger.log("org.open_power.Logging.Error.BadHostPEL",
                         Entry::Level::Error, ad);

        // Save it to a file for debug in the lab.  Just keep the latest.
        // Not adding it to the PEL because it could already be max size
        // and don't want to truncate an already invalid PEL.
        std::ofstream pelFile{getPELRepoPath() / "badPEL"};
        pelFile.write(reinterpret_cast<const char*>(pelData.data()),
                      pelData.size());
    }
}

void Manager::addESELPEL(const std::string& esel, uint32_t obmcLogID)
{
    std::vector<uint8_t> data;

    log<level::DEBUG>("Adding PEL from ESEL",
                      entry("OBMC_LOG_ID=%d", obmcLogID));

    try
    {
        data = std::move(eselToRawData(esel));
    }
    catch (std::exception& e)
    {
        // Try to add it below anyway, so it follows the usual bad data path.
        log<level::ERR>("Problems converting ESEL string to a byte vector");
    }

    addPEL(data, obmcLogID);
}

std::vector<uint8_t> Manager::eselToRawData(const std::string& esel)
{
    std::vector<uint8_t> data;
    std::string byteString;

    // As the eSEL string looks like: "50 48 00 ab ..." there are 3
    // characters per raw byte, and since the actual PEL data starts
    // at the 16th byte, the code will grab the PEL data starting at
    // offset 48 in the string.
    static constexpr size_t pelStart = 16 * 3;

    if (esel.size() <= pelStart)
    {
        log<level::ERR>("ESEL data too short",
                        entry("ESEL_SIZE=%d", esel.size()));

        throw std::length_error("ESEL data too short");
    }

    for (size_t i = pelStart; i < esel.size(); i += 3)
    {
        if (i + 1 < esel.size())
        {
            byteString = esel.substr(i, 2);
            data.push_back(std::stoi(byteString, nullptr, 16));
        }
        else
        {
            log<level::ERR>("ESEL data too short",
                            entry("ESEL_SIZE=%d", esel.size()));
            throw std::length_error("ESEL data too short");
        }
    }

    return data;
}

void Manager::erase(uint32_t obmcLogID)
{
    Repository::LogID id{Repository::LogID::Obmc(obmcLogID)};

    _repo.remove(id);
}

bool Manager::isDeleteProhibited(uint32_t obmcLogID)
{
    return false;
}

PelFFDC Manager::convertToPelFFDC(const FFDCEntries& ffdc)
{
    PelFFDC pelFFDC;

    std::for_each(ffdc.begin(), ffdc.end(), [&pelFFDC](const auto& f) {
        PelFFDCfile pf;
        pf.subType = std::get<ffdcSubtypePos>(f);
        pf.version = std::get<ffdcVersionPos>(f);
        pf.fd = std::get<ffdcFDPos>(f);

        switch (std::get<ffdcFormatPos>(f))
        {
            case Create::FFDCFormat::JSON:
                pf.format = UserDataFormat::json;
                break;
            case Create::FFDCFormat::CBOR:
                pf.format = UserDataFormat::cbor;
                break;
            case Create::FFDCFormat::Text:
                pf.format = UserDataFormat::text;
                break;
            case Create::FFDCFormat::Custom:
                pf.format = UserDataFormat::custom;
                break;
        }

        pelFFDC.push_back(pf);
    });

    return pelFFDC;
}

void Manager::createPEL(const std::string& message, uint32_t obmcLogID,
                        uint64_t timestamp,
                        phosphor::logging::Entry::Level severity,
                        const std::vector<std::string>& additionalData,
                        const std::vector<std::string>& associations,
                        const FFDCEntries& ffdc)
{
    auto entry = _registry.lookup(message, rg::LookupType::name);
    std::string msg;

    if (entry)
    {
        AdditionalData ad{additionalData};

        auto pelFFDC = convertToPelFFDC(ffdc);

        auto pel = std::make_unique<openpower::pels::PEL>(
            *entry, obmcLogID, timestamp, severity, ad, pelFFDC, *_dataIface);

        _repo.add(pel);

        if (_repo.sizeWarning())
        {
            scheduleRepoPrune();
        }

        auto src = pel->primarySRC();
        if (src)
        {
            using namespace std::literals::string_literals;
            auto id = getNumberString("0x%08X", pel->id());
            msg = "Created PEL "s + id + " with SRC "s + (*src)->asciiString();
            while (msg.back() == ' ')
            {
                msg.pop_back();
            }
            log<level::INFO>(msg.c_str());
        }
    }
    else
    {
        // TODO ibm-openbmc/dev/1151: Create a new PEL for this case.
        // For now, just trace it.
        msg = "Event not found in PEL message registry: " + message;
        log<level::INFO>(msg.c_str());
    }
}

sdbusplus::message::unix_fd Manager::getPEL(uint32_t pelID)
{
    Repository::LogID id{Repository::LogID::Pel(pelID)};
    std::optional<int> fd;

    log<level::DEBUG>("getPEL", entry("PEL_ID=0x%X", pelID));

    try
    {
        fd = _repo.getPELFD(id);
    }
    catch (std::exception& e)
    {
        throw common_error::InternalFailure();
    }

    if (!fd)
    {
        throw common_error::InvalidArgument();
    }

    scheduleFDClose(*fd);

    return *fd;
}

void Manager::scheduleFDClose(int fd)
{
    _fdCloserEventSource = std::make_unique<sdeventplus::source::Defer>(
        _event, std::bind(std::mem_fn(&Manager::closeFD), this, fd,
                          std::placeholders::_1));
}

void Manager::closeFD(int fd, sdeventplus::source::EventBase& source)
{
    close(fd);
    _fdCloserEventSource.reset();
}

std::vector<uint8_t> Manager::getPELFromOBMCID(uint32_t obmcLogID)
{
    Repository::LogID id{Repository::LogID::Obmc(obmcLogID)};
    std::optional<std::vector<uint8_t>> data;

    log<level::DEBUG>("getPELFromOBMCID", entry("OBMC_LOG_ID=%d", obmcLogID));

    try
    {
        data = _repo.getPELData(id);
    }
    catch (std::exception& e)
    {
        throw common_error::InternalFailure();
    }

    if (!data)
    {
        throw common_error::InvalidArgument();
    }

    return *data;
}

void Manager::hostAck(uint32_t pelID)
{
    Repository::LogID id{Repository::LogID::Pel(pelID)};

    log<level::DEBUG>("HostAck", entry("PEL_ID=0x%X", pelID));

    if (!_repo.hasPEL(id))
    {
        throw common_error::InvalidArgument();
    }

    if (_hostNotifier)
    {
        _hostNotifier->ackPEL(pelID);
    }
}

void Manager::hostReject(uint32_t pelID, RejectionReason reason)
{
    Repository::LogID id{Repository::LogID::Pel(pelID)};

    log<level::DEBUG>("HostReject", entry("PEL_ID=0x%X", pelID),
                      entry("REASON=%d", static_cast<int>(reason)));

    if (!_repo.hasPEL(id))
    {
        throw common_error::InvalidArgument();
    }

    if (reason == RejectionReason::BadPEL)
    {
        AdditionalData data;
        data.add("BAD_ID", getNumberString("0x%08X", pelID));
        _eventLogger.log("org.open_power.Logging.Error.SentBadPELToHost",
                         Entry::Level::Informational, data);
        if (_hostNotifier)
        {
            _hostNotifier->setBadPEL(pelID);
        }
    }
    else if ((reason == RejectionReason::HostFull) && _hostNotifier)
    {
        _hostNotifier->setHostFull(pelID);
    }
}

void Manager::scheduleRepoPrune()
{
    _repoPrunerEventSource = std::make_unique<sdeventplus::source::Defer>(
        _event, std::bind(std::mem_fn(&Manager::pruneRepo), this,
                          std::placeholders::_1));
}

void Manager::pruneRepo(sdeventplus::source::EventBase& source)
{
    auto idsToDelete = _repo.prune();

    // Remove the OpenBMC event logs for the PELs that were just removed.
    std::for_each(idsToDelete.begin(), idsToDelete.end(),
                  [this](auto id) { this->_logManager.erase(id); });

    _repoPrunerEventSource.reset();
}

void Manager::setupPELDeleteWatch()
{
    _pelFileDeleteFD = inotify_init1(IN_NONBLOCK);
    if (-1 == _pelFileDeleteFD)
    {
        auto e = errno;
        std::string msg =
            "inotify_init1 failed with errno " + std::to_string(e);
        log<level::ERR>(msg.c_str());
        abort();
    }

    _pelFileDeleteWatchFD = inotify_add_watch(
        _pelFileDeleteFD, _repo.repoPath().c_str(), IN_DELETE);
    if (-1 == _pelFileDeleteWatchFD)
    {
        auto e = errno;
        std::string msg =
            "inotify_add_watch failed with error " + std::to_string(e);
        log<level::ERR>(msg.c_str());
        abort();
    }

    _pelFileDeleteEventSource = std::make_unique<sdeventplus::source::IO>(
        _event, _pelFileDeleteFD, EPOLLIN,
        std::bind(std::mem_fn(&Manager::pelFileDeleted), this,
                  std::placeholders::_1, std::placeholders::_2,
                  std::placeholders::_3));
}

void Manager::pelFileDeleted(sdeventplus::source::IO& io, int fd,
                             uint32_t revents)
{
    if (!(revents & EPOLLIN))
    {
        return;
    }

    // An event for 1 PEL uses 48B. When all PELs are deleted at once,
    // as many events as there is room for can be handled in one callback.
    // A size of 2000 will allow 41 to be processed, with additional
    // callbacks being needed to process the remaining ones.
    std::array<uint8_t, 2000> data;
    auto bytesRead = read(_pelFileDeleteFD, data.data(), data.size());
    if (bytesRead < 0)
    {
        auto e = errno;
        std::string msg = "Failed reading data from inotify event, errno = " +
                          std::to_string(e);
        log<level::ERR>(msg.c_str());
        abort();
    }

    auto offset = 0;
    while (offset < bytesRead)
    {
        auto event = reinterpret_cast<inotify_event*>(&data[offset]);
        if (event->mask & IN_DELETE)
        {
            std::string filename{event->name};

            // Get the PEL ID from the filename and tell the
            // repo it's been removed, and then delete the BMC
            // event log if it's there.
            auto pos = filename.find_first_of('_');
            if (pos != std::string::npos)
            {
                try
                {
                    auto idString = filename.substr(pos + 1);
                    auto pelID = std::stoul(idString, nullptr, 16);

                    Repository::LogID id{Repository::LogID::Pel(pelID)};
                    auto removedLogID = _repo.remove(id);
                    if (removedLogID)
                    {
                        _logManager.erase(removedLogID->obmcID.id);
                    }
                }
                catch (const std::exception& e)
                {
                    log<level::INFO>("Could not find PEL ID from its filename",
                                     entry("FILENAME=%s", filename.c_str()));
                }
            }
        }

        offset += offsetof(inotify_event, name) + event->len;
    }
}
} // namespace pels
} // namespace openpower