/**
 * Copyright © 2017 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 "config.h"

#include "zone.hpp"

#include "sdbusplus.hpp"
#include "utility.hpp"

#include <cereal/archives/json.hpp>
#include <cereal/cereal.hpp>
#include <phosphor-logging/elog-errors.hpp>
#include <phosphor-logging/elog.hpp>
#include <phosphor-logging/log.hpp>
#include <xyz/openbmc_project/Common/error.hpp>

#include <chrono>
#include <filesystem>
#include <fstream>
#include <functional>
#include <stdexcept>

namespace phosphor
{
namespace fan
{
namespace control
{

using namespace std::chrono;
using namespace phosphor::fan;
using namespace phosphor::logging;
namespace fs = std::filesystem;
using InternalFailure =
    sdbusplus::xyz::openbmc_project::Common::Error::InternalFailure;

Zone::Zone(Mode mode, sdbusplus::bus_t& bus, const std::string& path,
           const sdeventplus::Event& event, const ZoneDefinition& def) :
    ThermalObject(bus, path.c_str(), ThermalObject::action::defer_emit),
    _bus(bus), _path(path),
    _ifaces({"xyz.openbmc_project.Control.ThermalMode"}),
    _fullSpeed(std::get<fullSpeedPos>(def)),
    _zoneNum(std::get<zoneNumPos>(def)),
    _defFloorSpeed(std::get<floorSpeedPos>(def)),
    _defCeilingSpeed(std::get<fullSpeedPos>(def)),
    _incDelay(std::get<incDelayPos>(def)),
    _decInterval(std::get<decIntervalPos>(def)),
    _incTimer(event, std::bind(&Zone::incTimerExpired, this)),
    _decTimer(event, std::bind(&Zone::decTimerExpired, this)), _eventLoop(event)
{
    auto& fanDefs = std::get<fanListPos>(def);

    for (auto& fanDef : fanDefs)
    {
        _fans.emplace_back(std::make_unique<Fan>(bus, fanDef));
    }

    // Do not enable set speed events when in init mode
    if (mode == Mode::control)
    {
        // Process any zone handlers defined
        for (auto& hand : std::get<handlerPos>(def))
        {
            hand(*this);
        }

        // Restore thermal control current mode state
        restoreCurrentMode();

        // Emit objects added in control mode only
        this->emit_object_added();

        // Update target speed to current zone target speed
        if (!_fans.empty())
        {
            _targetSpeed = _fans.front()->getTargetSpeed();
        }
        // Setup signal trigger for set speed events
        for (auto& ssEvent : std::get<setSpeedEventsPos>(def))
        {
            initEvent(ssEvent);
        }
        // Start timer for fan speed decreases
        _decTimer.restart(_decInterval);
    }
}

void Zone::setSpeed(uint64_t speed)
{
    if (_isActive)
    {
        _targetSpeed = speed;
        for (auto& fan : _fans)
        {
            fan->setSpeed(_targetSpeed);
        }
    }
}

void Zone::setFullSpeed()
{
    if (_fullSpeed != 0)
    {
        _targetSpeed = _fullSpeed;
        for (auto& fan : _fans)
        {
            fan->setSpeed(_targetSpeed);
        }
    }
}

void Zone::setActiveAllow(const Group* group, bool isActiveAllow)
{
    _active[*(group)] = isActiveAllow;
    if (!isActiveAllow)
    {
        _isActive = false;
    }
    else
    {
        // Check all entries are set to allow control active
        auto actPred = [](auto const& entry) { return entry.second; };
        _isActive = std::all_of(_active.begin(), _active.end(), actPred);
    }
}

void Zone::removeService(const Group* group, const std::string& name)
{
    try
    {
        auto& sNames = _services.at(*group);
        auto it = std::find_if(sNames.begin(), sNames.end(),
                               [&name](auto const& entry) {
                                   return name == std::get<namePos>(entry);
                               });
        if (it != std::end(sNames))
        {
            // Remove service name from group
            sNames.erase(it);
        }
    }
    catch (const std::out_of_range& oore)
    {
        // No services for group found
    }
}

void Zone::setServiceOwner(const Group* group, const std::string& name,
                           const bool hasOwner)
{
    try
    {
        auto& sNames = _services.at(*group);
        auto it = std::find_if(sNames.begin(), sNames.end(),
                               [&name](auto const& entry) {
                                   return name == std::get<namePos>(entry);
                               });
        if (it != std::end(sNames))
        {
            std::get<hasOwnerPos>(*it) = hasOwner;
        }
        else
        {
            _services[*group].emplace_back(name, hasOwner);
        }
    }
    catch (const std::out_of_range& oore)
    {
        _services[*group].emplace_back(name, hasOwner);
    }
}

void Zone::setServices(const Group* group)
{
    // Remove the empty service name if exists
    removeService(group, "");
    for (auto it = group->begin(); it != group->end(); ++it)
    {
        std::string name;
        bool hasOwner = false;
        try
        {
            name = getService(std::get<pathPos>(*it), std::get<intfPos>(*it));
            hasOwner = util::SDBusPlus::callMethodAndRead<bool>(
                _bus, "org.freedesktop.DBus", "/org/freedesktop/DBus",
                "org.freedesktop.DBus", "NameHasOwner", name);
        }
        catch (const util::DBusMethodError& e)
        {
            // Failed to get service name owner state
            hasOwner = false;
        }
        setServiceOwner(group, name, hasOwner);
    }
}

void Zone::setFloor(uint64_t speed)
{
    // Check all entries are set to allow floor to be set
    auto pred = [](auto const& entry) { return entry.second; };
    auto setFloor = std::all_of(_floorChange.begin(), _floorChange.end(), pred);
    if (setFloor)
    {
        _floorSpeed = speed;
        // Floor speed above target, update target to floor speed
        if (_targetSpeed < _floorSpeed)
        {
            requestSpeedIncrease(_floorSpeed - _targetSpeed);
        }
    }
}

void Zone::requestSpeedIncrease(uint64_t targetDelta)
{
    // Only increase speed when delta is higher than
    // the current increase delta for the zone and currently under ceiling
    if (targetDelta > _incSpeedDelta && _targetSpeed < _ceilingSpeed)
    {
        auto requestTarget = getRequestSpeedBase();
        requestTarget = (targetDelta - _incSpeedDelta) + requestTarget;
        _incSpeedDelta = targetDelta;
        // Target speed can not go above a defined ceiling speed
        if (requestTarget > _ceilingSpeed)
        {
            requestTarget = _ceilingSpeed;
        }
        setSpeed(requestTarget);
        // Retart timer countdown for fan speed increase
        _incTimer.restartOnce(_incDelay);
    }
}

void Zone::incTimerExpired()
{
    // Clear increase delta when timer expires allowing additional speed
    // increase requests or speed decreases to occur
    _incSpeedDelta = 0;
}

void Zone::requestSpeedDecrease(uint64_t targetDelta)
{
    // Only decrease the lowest target delta requested
    if (_decSpeedDelta == 0 || targetDelta < _decSpeedDelta)
    {
        _decSpeedDelta = targetDelta;
    }
}

void Zone::decTimerExpired()
{
    // Check all entries are set to allow a decrease
    auto pred = [](auto const& entry) { return entry.second; };
    auto decAllowed = std::all_of(_decAllowed.begin(), _decAllowed.end(), pred);

    // Only decrease speeds when allowed,
    // a requested decrease speed delta exists,
    // where no requested increases exist and
    // the increase timer is not running
    // (i.e. not in the middle of increasing)
    if (decAllowed && _decSpeedDelta != 0 && _incSpeedDelta == 0 &&
        !_incTimer.isEnabled())
    {
        auto requestTarget = getRequestSpeedBase();
        // Request target speed should not start above ceiling
        if (requestTarget > _ceilingSpeed)
        {
            requestTarget = _ceilingSpeed;
        }
        // Target speed can not go below the defined floor speed
        if ((requestTarget < _decSpeedDelta) ||
            (requestTarget - _decSpeedDelta < _floorSpeed))
        {
            requestTarget = _floorSpeed;
        }
        else
        {
            requestTarget = requestTarget - _decSpeedDelta;
        }
        setSpeed(requestTarget);
    }
    // Clear decrease delta when timer expires
    _decSpeedDelta = 0;
    // Decrease timer is restarted since its repeating
}

void Zone::initEvent(const SetSpeedEvent& event)
{
    // Enable event triggers
    std::for_each(
        std::get<triggerPos>(event).begin(), std::get<triggerPos>(event).end(),
        [this, &event](auto const& trigger) {
            if (!std::get<actionsPos>(event).empty())
            {
                std::for_each(
                    std::get<actionsPos>(event).begin(),
                    std::get<actionsPos>(event).end(),
                    [this, &trigger, &event](auto const& action) {
                        // Default to use group defined with action if exists
                        if (!std::get<adGroupPos>(action).empty())
                        {
                            trigger(*this, std::get<sseNamePos>(event),
                                    std::get<adGroupPos>(action),
                                    std::get<adActionsPos>(action));
                        }
                        else
                        {
                            trigger(*this, std::get<sseNamePos>(event),
                                    std::get<groupPos>(event),
                                    std::get<adActionsPos>(action));
                        }
                    });
            }
            else
            {
                trigger(*this, std::get<sseNamePos>(event),
                        std::get<groupPos>(event), {});
            }
        });
}

void Zone::removeEvent(const SetSpeedEvent& event)
{
    // Remove event signals
    auto sigIter = _signalEvents.find(std::get<sseNamePos>(event));
    if (sigIter != _signalEvents.end())
    {
        auto& signals = sigIter->second;
        for (auto it = signals.begin(); it != signals.end(); ++it)
        {
            removeSignal(it);
        }
        _signalEvents.erase(sigIter);
    }

    // Remove event timers
    auto timIter = _timerEvents.find(std::get<sseNamePos>(event));
    if (timIter != _timerEvents.end())
    {
        _timerEvents.erase(timIter);
    }
}

std::vector<TimerEvent>::iterator
    Zone::findTimer(const Group& eventGroup,
                    const std::vector<Action>& eventActions,
                    std::vector<TimerEvent>& eventTimers)
{
    for (auto it = eventTimers.begin(); it != eventTimers.end(); ++it)
    {
        const auto& teEventData = *std::get<timerEventDataPos>(*it);
        if (std::get<eventGroupPos>(teEventData) == eventGroup &&
            std::get<eventActionsPos>(teEventData).size() ==
                eventActions.size())
        {
            // TODO openbmc/openbmc#2328 - Use the action function target
            // for comparison
            auto actsEqual = [](auto const& a1, auto const& a2) {
                return a1.target_type().name() == a2.target_type().name();
            };
            if (std::equal(eventActions.begin(), eventActions.end(),
                           std::get<eventActionsPos>(teEventData).begin(),
                           actsEqual))
            {
                return it;
            }
        }
    }

    return eventTimers.end();
}

void Zone::addTimer(const std::string& name, const Group& group,
                    const std::vector<Action>& actions, const TimerConf& tConf)
{
    auto eventData = std::make_unique<EventData>(group, "", nullptr, actions);
    Timer timer(
        _eventLoop,
        std::bind(&Zone::timerExpired, this,
                  std::cref(std::get<Group>(*eventData)),
                  std::cref(std::get<std::vector<Action>>(*eventData))));
    if (std::get<TimerType>(tConf) == TimerType::repeating)
    {
        timer.restart(std::get<intervalPos>(tConf));
    }
    else if (std::get<TimerType>(tConf) == TimerType::oneshot)
    {
        timer.restartOnce(std::get<intervalPos>(tConf));
    }
    else
    {
        throw std::invalid_argument("Invalid Timer Type");
    }
    _timerEvents[name].emplace_back(std::move(eventData), std::move(timer));
}

void Zone::timerExpired(const Group& eventGroup,
                        const std::vector<Action>& eventActions)
{
    // Perform the actions
    std::for_each(
        eventActions.begin(), eventActions.end(),
        [this, &eventGroup](auto const& action) { action(*this, eventGroup); });
}

void Zone::handleEvent(sdbusplus::message_t& msg, const EventData* eventData)
{
    // Handle the callback
    std::get<eventHandlerPos> (*eventData)(_bus, msg, *this);
    // Perform the actions
    std::for_each(std::get<eventActionsPos>(*eventData).begin(),
                  std::get<eventActionsPos>(*eventData).end(),
                  [this, &eventData](auto const& action) {
                      action(*this, std::get<eventGroupPos>(*eventData));
                  });
}

const std::string& Zone::getService(const std::string& path,
                                    const std::string& intf)
{
    // Retrieve service from cache
    auto srvIter = _servTree.find(path);
    if (srvIter != _servTree.end())
    {
        for (auto& serv : srvIter->second)
        {
            auto it = std::find_if(
                serv.second.begin(), serv.second.end(),
                [&intf](auto const& interface) { return intf == interface; });
            if (it != std::end(serv.second))
            {
                // Service found
                return serv.first;
            }
        }
        // Interface not found in cache, add and return
        return addServices(path, intf, 0);
    }
    else
    {
        // Path not found in cache, add and return
        return addServices(path, intf, 0);
    }
}

const std::string& Zone::addServices(const std::string& path,
                                     const std::string& intf, int32_t depth)
{
    static const std::string empty = "";
    auto it = _servTree.end();

    // Get all subtree objects for the given interface
    auto objects = util::SDBusPlus::getSubTree(_bus, "/", intf, depth);
    // Add what's returned to the cache of path->services
    for (auto& pIter : objects)
    {
        auto pathIter = _servTree.find(pIter.first);
        if (pathIter != _servTree.end())
        {
            // Path found in cache
            for (auto& sIter : pIter.second)
            {
                auto servIter = pathIter->second.find(sIter.first);
                if (servIter != pathIter->second.end())
                {
                    // Service found in cache
                    for (auto& iIter : sIter.second)
                    {
                        if (std::find(servIter->second.begin(),
                                      servIter->second.end(),
                                      iIter) == servIter->second.end())
                        {
                            // Add interface to cache
                            servIter->second.emplace_back(iIter);
                        }
                    }
                }
                else
                {
                    // Service not found in cache
                    pathIter->second.insert(sIter);
                }
            }
        }
        else
        {
            _servTree.insert(pIter);
        }
        // When the paths match, since a single interface constraint is given,
        // that is the service to return
        if (path == pIter.first)
        {
            it = _servTree.find(pIter.first);
        }
    }

    if (it != _servTree.end())
    {
        return it->second.begin()->first;
    }

    return empty;
}

auto Zone::getPersisted(const std::string& intf, const std::string& prop)
{
    auto persisted = false;

    auto it = _persisted.find(intf);
    if (it != _persisted.end())
    {
        return std::any_of(it->second.begin(), it->second.end(),
                           [&prop](const auto& p) { return prop == p; });
    }

    return persisted;
}

std::string Zone::current(std::string value)
{
    auto current = ThermalObject::current();
    std::transform(value.begin(), value.end(), value.begin(), toupper);

    auto supported = ThermalObject::supported();
    auto isSupported =
        std::any_of(supported.begin(), supported.end(), [&value](auto& s) {
            std::transform(s.begin(), s.end(), s.begin(), toupper);
            return value == s;
        });

    if (value != current && isSupported)
    {
        current = ThermalObject::current(value);
        if (getPersisted("xyz.openbmc_project.Control.ThermalMode", "Current"))
        {
            saveCurrentMode();
        }
        // Trigger event(s) for current mode property change
        auto eData = _objects[_path]["xyz.openbmc_project.Control.ThermalMode"]
                             ["Current"];
        if (eData != nullptr)
        {
            sdbusplus::message_t nullMsg{nullptr};
            handleEvent(nullMsg, eData);
        }
    }

    return current;
}

void Zone::saveCurrentMode()
{
    fs::path path{CONTROL_PERSIST_ROOT_PATH};
    // Append zone and property description
    path /= std::to_string(_zoneNum);
    path /= "CurrentMode";
    std::ofstream ofs(path.c_str(), std::ios::binary);
    cereal::JSONOutputArchive oArch(ofs);
    oArch(ThermalObject::current());
}

void Zone::restoreCurrentMode()
{
    auto current = ThermalObject::current();
    fs::path path{CONTROL_PERSIST_ROOT_PATH};
    path /= std::to_string(_zoneNum);
    path /= "CurrentMode";
    fs::create_directories(path.parent_path());

    try
    {
        if (fs::exists(path))
        {
            std::ifstream ifs(path.c_str(), std::ios::in | std::ios::binary);
            cereal::JSONInputArchive iArch(ifs);
            iArch(current);
        }
    }
    catch (const std::exception& e)
    {
        log<level::ERR>(e.what());
        fs::remove(path);
        current = ThermalObject::current();
    }

    this->current(current);
}

} // namespace control
} // namespace fan
} // namespace phosphor