/*
  Copyright 2016 SINTEF ICT, Applied Mathematics.
  Copyright 2016 - 2017 Statoil ASA.
  Copyright 2017 Dr. Blatt - HPC-Simulation-Software & Services
  Copyright 2016 - 2018 IRIS AS

  This file is part of the Open Porous Media project (OPM).

  OPM is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  OPM 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 General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with OPM.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <config.h>

#include <opm/simulators/wells/BlackoilWellModelGeneric.hpp>

#include <opm/common/ErrorMacros.hpp>

#include <opm/output/data/GuideRateValue.hpp>
#include <opm/output/data/Groups.hpp>
#include <opm/output/data/Wells.hpp>
#include <opm/output/eclipse/RestartValue.hpp>

#include <opm/input/eclipse/EclipseState/EclipseState.hpp>
#include <opm/input/eclipse/EclipseState/SummaryConfig/SummaryConfig.hpp>

#include <opm/input/eclipse/Schedule/Action/SimulatorUpdate.hpp>
#include <opm/input/eclipse/Schedule/Group/GConSale.hpp>
#include <opm/input/eclipse/Schedule/Group/GroupEconProductionLimits.hpp>
#include <opm/input/eclipse/Schedule/Group/GConSump.hpp>
#include <opm/input/eclipse/Schedule/Group/GuideRateConfig.hpp>
#include <opm/input/eclipse/Schedule/Group/GuideRate.hpp>
#include <opm/input/eclipse/Schedule/Network/Balance.hpp>
#include <opm/input/eclipse/Schedule/Network/ExtNetwork.hpp>
#include <opm/input/eclipse/Schedule/Schedule.hpp>
#include <opm/input/eclipse/Schedule/ScheduleTypes.hpp>
#include <opm/input/eclipse/Schedule/Well/WellConnections.hpp>
#include <opm/input/eclipse/Schedule/Well/WellTestConfig.hpp>

#include <opm/input/eclipse/Units/Units.hpp>

#include <opm/simulators/utils/DeferredLogger.hpp>
#include <opm/simulators/wells/BlackoilWellModelConstraints.hpp>
#include <opm/simulators/wells/BlackoilWellModelGuideRates.hpp>
#include <opm/simulators/wells/BlackoilWellModelRestart.hpp>
#include <opm/simulators/wells/GasLiftStage2.hpp>
#include <opm/simulators/wells/GroupEconomicLimitsChecker.hpp>
#include <opm/simulators/wells/ParallelWBPCalculation.hpp>
#include <opm/simulators/wells/VFPProperties.hpp>
#include <opm/simulators/wells/WellFilterCake.hpp>
#include <opm/simulators/wells/WellGroupHelpers.hpp>
#include <opm/simulators/wells/WellInterfaceGeneric.hpp>
#include <opm/simulators/wells/WellState.hpp>

#if HAVE_MPI
#include <opm/simulators/utils/MPISerializer.hpp>
#endif

#include <algorithm>
#include <cassert>
#include <functional>
#include <stack>
#include <stdexcept>
#include <string_view>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <vector>

#include <fmt/format.h>

namespace Opm {

template<class Scalar>
BlackoilWellModelGeneric<Scalar>::
BlackoilWellModelGeneric(Schedule& schedule,
                         const SummaryState& summaryState,
                         const EclipseState& eclState,
                         const PhaseUsage& phase_usage,
                         const Parallel::Communication& comm)
    : schedule_(schedule)
    , summaryState_(summaryState)
    , eclState_(eclState)
    , comm_(comm)
    , phase_usage_(phase_usage)
    , wbpCalculationService_ { eclState.gridDims(), comm_ }
    , guideRate_(schedule)
    , active_wgstate_(phase_usage)
    , last_valid_wgstate_(phase_usage)
    , nupcol_wgstate_(phase_usage)
{

    const auto numProcs = comm_.size();
    this->not_on_process_ = [this, numProcs](const Well& well) {
        if (numProcs == decltype(numProcs){1})
            return false;

        // Recall: false indicates NOT active!
        const auto value = std::make_pair(well.name(), true);
        auto candidate = std::lower_bound(this->parallel_well_info_.begin(),
                                          this->parallel_well_info_.end(),
                                          value);

        return (candidate == this->parallel_well_info_.end())
                || (*candidate != value);
    };

    const auto& node_pressures = eclState.getRestartNetworkPressures();
    if (node_pressures.has_value()) {
        if constexpr (std::is_same_v<Scalar,double>) {
            this->node_pressures_ = node_pressures.value();
        } else {
            for (const auto& it : node_pressures.value()) {
                this->node_pressures_[it.first] = it.second;
            }
        }
    }
}

template<class Scalar>
int BlackoilWellModelGeneric<Scalar>::
numLocalWells() const
{
    return wells_ecl_.size();
}

template<class Scalar>
int BlackoilWellModelGeneric<Scalar>::
numPhases() const
{
    return phase_usage_.num_phases;
}

template<class Scalar>
bool BlackoilWellModelGeneric<Scalar>::
hasWell(const std::string& wname) const
{
    return std::any_of(this->wells_ecl_.begin(), this->wells_ecl_.end(),
        [&wname](const Well& well)
    {
        return well.name() == wname;
    });
}

template<class Scalar>
bool BlackoilWellModelGeneric<Scalar>::
wellsActive() const
{
    return wells_active_;
}

template<class Scalar>
bool BlackoilWellModelGeneric<Scalar>::
networkActive() const
{
    return network_active_;
}

template<class Scalar>
bool BlackoilWellModelGeneric<Scalar>::
anyMSWellOpenLocal() const
{
    for (const auto& well : wells_ecl_) {
        if (well.isMultiSegment()) {
            return true;
        }
    }
    return false;
}

template<class Scalar>
const Well& BlackoilWellModelGeneric<Scalar>::
getWellEcl(const std::string& well_name) const
{
    // finding the iterator of the well in wells_ecl
    auto well_ecl = std::find_if(wells_ecl_.begin(),
                                 wells_ecl_.end(),
                                 [&well_name](const Well& elem)->bool {
                                     return elem.name() == well_name;
                                 });

    assert(well_ecl != wells_ecl_.end());

    return *well_ecl;
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
initFromRestartFile(const RestartValue& restartValues,
                    std::unique_ptr<WellTestState> wtestState,
                    const std::size_t numCells,
                    bool handle_ms_well)
{
    // The restart step value is used to identify wells present at the given
    // time step. Wells that are added at the same time step as RESTART is initiated
    // will not be present in a restart file. Use the previous time step to retrieve
    // wells that have information written to the restart file.
    const int report_step = std::max(eclState_.getInitConfig().getRestartStep() - 1, 0);

    const auto& config = this->schedule()[report_step].guide_rate();

    // wells_ecl_ should only contain wells on this processor.
    wells_ecl_ = getLocalWells(report_step);
    this->local_parallel_well_info_ = createLocalParallelWellInfo(wells_ecl_);

    this->initializeWellProdIndCalculators();
    initializeWellPerfData();

    handle_ms_well &= anyMSWellOpenLocal();
    // Resize for restart step
    this->wellState().resize(this->wells_ecl_, this->local_parallel_well_info_,
                             this->schedule(), handle_ms_well, numCells,
                             this->well_perf_data_, this->summaryState_);

    BlackoilWellModelRestart(*this).
        loadRestartData(restartValues.wells,
                        restartValues.grp_nwrk,
                        handle_ms_well,
                        this->wellState(),
                        this->groupState());

    if (config.has_model()) {
        BlackoilWellModelRestart(*this).
            loadRestartGuideRates(report_step,
                                  config.model().target(),
                                  restartValues.wells,
                                  this->guideRate_);
    }

    if (config.has_model()) {
        BlackoilWellModelRestart(*this).
            loadRestartGuideRates(report_step,
                                  config,
                                  restartValues.grp_nwrk.groupData,
                                  this->guideRate_);

        this->guideRate_.updateGuideRateExpiration(this->schedule().seconds(report_step), report_step);
    }

    this->active_wgstate_.wtest_state(std::move(wtestState));
    this->commitWGState();
    initial_step_ = false;
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
prepareDeserialize(int report_step, const std::size_t numCells, bool handle_ms_well)
{
    // wells_ecl_ should only contain wells on this processor.
    wells_ecl_ = getLocalWells(report_step);
    this->local_parallel_well_info_ = createLocalParallelWellInfo(wells_ecl_);

    this->initializeWellProdIndCalculators();
    initializeWellPerfData();

    if (! this->wells_ecl_.empty()) {
        handle_ms_well &= anyMSWellOpenLocal();
        this->wellState().resize(this->wells_ecl_, this->local_parallel_well_info_,
                                 this->schedule(), handle_ms_well, numCells,
                                 this->well_perf_data_, this->summaryState_);

    }
    this->wellState().clearWellRates();
    this->commitWGState();
    this->updateNupcolWGState();
}

template<class Scalar>
std::vector<Well> BlackoilWellModelGeneric<Scalar>::
getLocalWells(const int timeStepIdx) const
{
    auto w = schedule().getWells(timeStepIdx);
    w.erase(std::remove_if(w.begin(), w.end(), not_on_process_), w.end());
    return w;
}

template<class Scalar>
std::vector<std::reference_wrapper<ParallelWellInfo<Scalar>>>
BlackoilWellModelGeneric<Scalar>::
createLocalParallelWellInfo(const std::vector<Well>& wells)
{
    std::vector<std::reference_wrapper<ParallelWellInfo<Scalar>>> local_parallel_well_info;
    local_parallel_well_info.reserve(wells.size());
    for (const auto& well : wells)
    {
        auto wellPair = std::make_pair(well.name(), true);
        auto pwell = std::lower_bound(parallel_well_info_.begin(),
                                      parallel_well_info_.end(),
                                      wellPair);
        assert(pwell != parallel_well_info_.end() &&
               *pwell == wellPair);
        local_parallel_well_info.push_back(std::ref(*pwell));
    }
    return local_parallel_well_info;
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
initializeWellProdIndCalculators()
{
    this->prod_index_calc_.clear();
    this->prod_index_calc_.reserve(this->wells_ecl_.size());
    for (const auto& well : this->wells_ecl_) {
        this->prod_index_calc_.emplace_back(well);
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
initializeWellPerfData()
{
    well_perf_data_.resize(wells_ecl_.size());

    this->conn_idx_map_.clear();
    this->conn_idx_map_.reserve(wells_ecl_.size());

    int well_index = 0;
    for (const auto& well : wells_ecl_) {
        int connection_index = 0;

        // INVALID_ECL_INDEX marks no above perf available
        int connection_index_above = ParallelWellInfo<Scalar>::INVALID_ECL_INDEX;

        well_perf_data_[well_index].clear();
        well_perf_data_[well_index].reserve(well.getConnections().size());

        auto& connIdxMap = this->conn_idx_map_
            .emplace_back(well.getConnections().size());

        CheckDistributedWellConnections checker {
            well, this->local_parallel_well_info_[well_index].get()
        };

        bool hasFirstConnection = false;
        bool firstOpenConnection = true;

        auto& parallelWellInfo = this->local_parallel_well_info_[well_index].get();
        parallelWellInfo.beginReset();

        for (const auto& connection : well.getConnections()) {
            const auto active_index =
                this->compressedIndexForInterior(connection.global_index());

            const auto connIsOpen =
                connection.state() == Connection::State::OPEN;

            if (active_index >= 0) {
                connIdxMap.addActiveConnection(connection_index, connIsOpen);
            }

            if ((connIsOpen && (active_index >= 0)) || !connIsOpen) {
                checker.connectionFound(connection_index);
            }

            if (connIsOpen) {
                if (active_index >= 0) {
                    if (firstOpenConnection) {
                        hasFirstConnection = true;
                    }

                    auto& pd = well_perf_data_[well_index].emplace_back();

                    pd.cell_index = active_index;
                    pd.connection_transmissibility_factor = connection.CF();
                    pd.satnum_id = connection.satTableId();
                    pd.ecl_index = connection_index;

                    parallelWellInfo.pushBackEclIndex(connection_index_above,
                                                      connection_index);
                }

                firstOpenConnection = false;

                // Next time this index is the one above as each open
                // connection is stored somewhere.
                connection_index_above = connection_index;
            }
            else if (connection.state() != Connection::State::SHUT) {
                OPM_THROW(std::runtime_error,
                          fmt::format("Connection state '{}' not handled",
                                      Connection::State2String(connection.state())));
            }

            // Note: we rely on the connections being filtered!  I.e., there
            // are only connections to active cells in the global grid.
            ++connection_index;
        }

        parallelWellInfo.endReset();

        checker.checkAllConnectionsFound();

        parallelWellInfo.communicateFirstPerforation(hasFirstConnection);

        ++well_index;
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
checkGEconLimits(
        const Group& group,
        const double simulation_time,
        const int report_step_idx,
        DeferredLogger& deferred_logger)
{
     // call recursively down the group hiearchy
    for (const std::string& group_name : group.groups()) {
        checkGEconLimits( schedule().getGroup(group_name, report_step_idx),
                          simulation_time, report_step_idx, deferred_logger);
    }

    // check if gecon is used for this group
    if (!schedule()[report_step_idx].gecon().has_group(group.name())) {
        return;
    }

    GroupEconomicLimitsChecker<Scalar> checker {
        *this, wellTestState(), group, simulation_time, report_step_idx, deferred_logger
    };
    if (checker.minOilRate() || checker.minGasRate()) {
        checker.closeWells();
    }
    else if (checker.waterCut() || checker.GOR() || checker.WGR()) {
        checker.doWorkOver();
    }
    if (checker.endRun() && (checker.numProducersOpenInitially() >= 1)
                             && (checker.numProducersOpen() == 0))
    {
        checker.activateEndRun();
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
checkGconsaleLimits(const Group& group,
                    WellState<Scalar>& well_state,
                    const int reportStepIdx,
                    DeferredLogger& deferred_logger)
{
     // call recursively down the group hiearchy
    for (const std::string& groupName : group.groups()) {
        checkGconsaleLimits( schedule().getGroup(groupName, reportStepIdx), well_state, reportStepIdx, deferred_logger);
    }

    // only for groups with gas injection controls
    if (!group.hasInjectionControl(Phase::GAS)) {
        return;
    }

    // check if gconsale is used for this group
    if (!schedule()[reportStepIdx].gconsale().has(group.name()))
        return;

    std::string ss;

    const auto& gconsale = schedule()[reportStepIdx].gconsale().get(group.name(), summaryState_);
    const Group::ProductionCMode& oldProductionControl = this->groupState().production_control(group.name());

    int gasPos = phase_usage_.phase_pos[BlackoilPhases::Vapour];
    Scalar production_rate = WellGroupHelpers<Scalar>::sumWellSurfaceRates(group,
                                                                           schedule(),
                                                                           well_state,
                                                                           reportStepIdx,
                                                                           gasPos,
                                                                           /*isInjector*/false);
    Scalar injection_rate = WellGroupHelpers<Scalar>::sumWellSurfaceRates(group,
                                                                          schedule(),
                                                                          well_state,
                                                                          reportStepIdx,
                                                                          gasPos,
                                                                          /*isInjector*/true);
    // sum over all nodes
    injection_rate = comm_.sum(injection_rate);
    production_rate = comm_.sum(production_rate);

    Scalar sales_rate = production_rate - injection_rate;
    Scalar production_target = gconsale.sales_target + injection_rate;

    // add import rate and subtract consumption rate for group for gas
    if (schedule()[reportStepIdx].gconsump().has(group.name())) {
        const auto& gconsump = schedule()[reportStepIdx].gconsump().get(group.name(), summaryState_);
        if (phase_usage_.phase_used[BlackoilPhases::Vapour]) {
            sales_rate += gconsump.import_rate;
            sales_rate -= gconsump.consumption_rate;
            production_target -= gconsump.import_rate;
            production_target += gconsump.consumption_rate;
        }
    }

    if (sales_rate > gconsale.max_sales_rate) {
        switch (gconsale.max_proc) {
        case GConSale::MaxProcedure::NONE: {
            if (oldProductionControl != Group::ProductionCMode::GRAT && oldProductionControl != Group::ProductionCMode::NONE) {
                ss = fmt::format("Group sales exceed maximum limit, but the action is NONE for {}. Nothing happens",
                                 group.name());
            }
            break;
            }
        case GConSale::MaxProcedure::CON: {
            OPM_DEFLOG_THROW(std::runtime_error, "Group " + group.name() + "GCONSALE exceed limit CON not implemented", deferred_logger);
            break;
        }
        case GConSale::MaxProcedure::CON_P: {
            OPM_DEFLOG_THROW(std::runtime_error, "Group " + group.name() + "GCONSALE exceed limit CON_P not implemented", deferred_logger);
            break;
        }
        case GConSale::MaxProcedure::WELL: {
            OPM_DEFLOG_THROW(std::runtime_error, "Group " + group.name() + "GCONSALE exceed limit WELL not implemented", deferred_logger);
            break;
        }
        case GConSale::MaxProcedure::PLUG: {
            OPM_DEFLOG_THROW(std::runtime_error, "Group " + group.name() + "GCONSALE exceed limit PLUG not implemented", deferred_logger);
            break;
        }
        case GConSale::MaxProcedure::MAXR: {
            OPM_DEFLOG_THROW(std::runtime_error, "Group " + group.name() + "GCONSALE exceed limit MAXR not implemented", deferred_logger);
            break;
        }
        case GConSale::MaxProcedure::END: {
            OPM_DEFLOG_THROW(std::runtime_error, "Group " + group.name() + "GCONSALE exceed limit END not implemented", deferred_logger);
            break;
        }
        case GConSale::MaxProcedure::RATE: {
            this->groupState().production_control(group.name(), Group::ProductionCMode::GRAT);
            ss = fmt::format("Maximum GCONSALE limit violated for {}. "
                             "The group is switched from {} to {} "
                             "and limited by the maximum sales rate after "
                             "consumption and import are considered",
                             group.name(),
                             Group::ProductionCMode2String(oldProductionControl),
                             Group::ProductionCMode2String(Group::ProductionCMode::GRAT));
            this->groupState().update_grat_sales_target(group.name(), production_target);
            break;
        }
        default:
            throw("Invalid procedure for maximum rate limit selected for group" + group.name());
        }
    }
    if (sales_rate < gconsale.min_sales_rate) {
        const Group::ProductionCMode& currentProductionControl = this->groupState().production_control(group.name());
        if ( currentProductionControl == Group::ProductionCMode::GRAT ) {
            ss = fmt::format("Group {} has sale rate less then minimum permitted value and is under GRAT control.\n"
                             "The GRAT is increased to meet the sales minimum rate.",
                             group.name());
            this->groupState().update_grat_sales_target(group.name(), production_target);
        //} else if () {//TODO add action for WGASPROD
        //} else if () {//TODO add action for drilling queue
        } else {
            ss = fmt::format("Group {} has sale rate less then minimum permitted value but cannot increase the group production rate \n"
                             "or adjust gas production using WGASPROD or drill new wells to meet the sales target. \n"
                             "Note that WGASPROD and drilling queues are not implemented in Flow. No action is taken.",
                             group.name());
        }
    }
    if (gconsale.sales_target < 0.0) {
        OPM_DEFLOG_THROW(std::runtime_error, "Group " + group.name() + " has sale rate target less then zero. Not implemented in Flow" , deferred_logger);
    }

    if (!ss.empty() && comm_.rank() == 0)
        deferred_logger.info(ss);
}

template<class Scalar>
bool BlackoilWellModelGeneric<Scalar>::
checkGroupHigherConstraints(const Group& group,
                            DeferredLogger& deferred_logger,
                            const int reportStepIdx)
{
    // Set up coefficients for RESV <-> surface rate conversion.
    // Use the pvtRegionIdx from the top cell of the first well.
    // TODO fix this!
    // This is only used for converting RESV rates.
    // What is the proper approach?
    const int fipnum = 0;
    int pvtreg = well_perf_data_.empty() || well_perf_data_[0].empty()
        ? pvt_region_idx_[0]
        : pvt_region_idx_[well_perf_data_[0][0].cell_index];

    bool changed = false;
    if ( comm_.size() > 1)
    {
        // Just like in the sequential case the pvtregion is determined
        // by the first cell of the first well. What is the first well
        // is decided by the order in the Schedule using Well::seqIndex()
        int firstWellIndex = well_perf_data_.empty() ?
            std::numeric_limits<int>::max() : wells_ecl_[0].seqIndex();
        auto regIndexPair = std::make_pair(pvtreg, firstWellIndex);
        std::vector<decltype(regIndexPair)> pairs(comm_.size());
        comm_.allgather(&regIndexPair, 1, pairs.data());
        pvtreg = std::min_element(pairs.begin(), pairs.end(),
                                  [](const auto& p1, const auto& p2){ return p1.second < p2.second;})
            ->first;
    }

    std::vector<Scalar> rates(phase_usage_.num_phases, 0.0);

    bool isField = group.name() == "FIELD";
    if (!isField && group.isInjectionGroup()) {
        // Obtain rates for group.
        std::vector<Scalar> resv_coeff_inj(phase_usage_.num_phases, 0.0);
        calcInjResvCoeff(fipnum, pvtreg, resv_coeff_inj);

        for (int phasePos = 0; phasePos < phase_usage_.num_phases; ++phasePos) {
            const Scalar local_current_rate = WellGroupHelpers<Scalar>::sumWellSurfaceRates(group,
                                                                                            schedule(),
                                                                                            this->wellState(),
                                                                                            reportStepIdx,
                                                                                            phasePos,
                                                                                            /* isInjector */ true);
            // Sum over all processes
            rates[phasePos] = comm_.sum(local_current_rate);
        }
        const Phase all[] = { Phase::WATER, Phase::OIL, Phase::GAS };
        for (Phase phase : all) {
            // Check higher up only if under individual (not FLD) control.
            auto currentControl = this->groupState().injection_control(group.name(), phase);
            if (currentControl != Group::InjectionCMode::FLD && group.injectionGroupControlAvailable(phase)) {
                const Group& parentGroup = schedule().getGroup(group.parent(), reportStepIdx);
                const auto [is_changed, scaling_factor] =
                    WellGroupHelpers<Scalar>::checkGroupConstraintsInj(group.name(),
                                                                       group.parent(),
                                                                       parentGroup,
                                                                       this->wellState(),
                                                                       this->groupState(),
                                                                       reportStepIdx,
                                                                       &guideRate_,
                                                                       rates.data(),
                                                                       phase,
                                                                       phase_usage_,
                                                                       group.getGroupEfficiencyFactor(),
                                                                       schedule(),
                                                                       summaryState_,
                                                                       resv_coeff_inj,
                                                                       deferred_logger);
                if (is_changed) {
                    switched_inj_groups_.insert_or_assign({group.name(), phase}, Group::InjectionCMode2String(Group::InjectionCMode::FLD));
                    BlackoilWellModelConstraints(*this).
                        actionOnBrokenConstraints(group, Group::InjectionCMode::FLD,
                                                  phase, this->groupState(),
                                                  deferred_logger);
                    WellGroupHelpers<Scalar>::updateWellRatesFromGroupTargetScale(scaling_factor,
                                                                                  group,
                                                                                  schedule(),
                                                                                  reportStepIdx,
                                                                                  /* isInjector */ true,
                                                                                  this->groupState(),
                                                                                  this->wellState());
                    changed = true;
                }
            }
        }
    }

    if (!isField && group.isProductionGroup()) {
        // Obtain rates for group.
        for (int phasePos = 0; phasePos < phase_usage_.num_phases; ++phasePos) {
            const Scalar local_current_rate = WellGroupHelpers<Scalar>::sumWellSurfaceRates(group,
                                                                                            schedule(),
                                                                                            this->wellState(),
                                                                                            reportStepIdx,
                                                                                            phasePos,
                                                                                            /* isInjector */ false);
            // Sum over all processes
            rates[phasePos] = -comm_.sum(local_current_rate);
        }
        std::vector<Scalar> resv_coeff(phase_usage_.num_phases, 0.0);
        calcResvCoeff(fipnum, pvtreg, this->groupState().production_rates(group.name()), resv_coeff);
        // Check higher up only if under individual (not FLD) control.
        const Group::ProductionCMode& currentControl = this->groupState().production_control(group.name());
        if (currentControl != Group::ProductionCMode::FLD && group.productionGroupControlAvailable()) {
            const Group& parentGroup = schedule().getGroup(group.parent(), reportStepIdx);
            const auto [is_changed, scaling_factor] =
                WellGroupHelpers<Scalar>::checkGroupConstraintsProd(group.name(),
                                                                    group.parent(),
                                                                    parentGroup,
                                                                    this->wellState(),
                                                                    this->groupState(),
                                                                    reportStepIdx,
                                                                    &guideRate_,
                                                                    rates.data(),
                                                                    phase_usage_,
                                                                    group.getGroupEfficiencyFactor(),
                                                                    schedule(),
                                                                    summaryState_,
                                                                    resv_coeff,
                                                                    deferred_logger);
            if (is_changed) {
                const auto group_limit_action = group.productionControls(summaryState_).group_limit_action;
                std::optional<std::string> worst_offending_well = std::nullopt; 
                changed = BlackoilWellModelConstraints(*this).
                        actionOnBrokenConstraints(group, reportStepIdx, group_limit_action,
                                                  Group::ProductionCMode::FLD,
                                                  this->wellState(),
                                                  worst_offending_well,
                                                  this->groupState(),
                                                  deferred_logger);

                if (changed) {
                    switched_prod_groups_.insert_or_assign(group.name(),
                                                           Group::ProductionCMode2String(Group::ProductionCMode::FLD));
                    WellGroupHelpers<Scalar>::updateWellRatesFromGroupTargetScale(scaling_factor,
                                                                                  group,
                                                                                  schedule(),
                                                                                  reportStepIdx,
                                                                                  /* isInjector */ false,
                                                                                  this->groupState(),
                                                                                  this->wellState());
                }
            }
        }
    }

    return changed;
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
updateEclWells(const int timeStepIdx,
               const SimulatorUpdate& sim_update,
               const SummaryState& st)
{
    for (const auto& wname : sim_update.affected_wells) {
        auto well_iter = std::find_if(this->wells_ecl_.begin(), this->wells_ecl_.end(),
            [&wname] (const auto& well) -> bool
        {
            return well.name() == wname;
        });

        if (well_iter == this->wells_ecl_.end()) {
            continue;
        }

        const auto well_index = std::distance(this->wells_ecl_.begin(), well_iter);

        const auto& well = this->wells_ecl_[well_index] =
            this->schedule_.getWell(wname, timeStepIdx);

        auto& pd = this->well_perf_data_[well_index];

        {
            auto pdIter = pd.begin();

            for (const auto& conn : well.getConnections()) {
                if (conn.state() != Connection::State::SHUT) {
                    pdIter->connection_transmissibility_factor = conn.CF();
                    ++pdIter;
                }
            }
        }

        {
            auto& ws = this->wellState().well(well_index);

            ws.updateStatus(well.getStatus());
            ws.reset_connection_factors(pd);
            ws.update_targets(well, st);
        }

        this->prod_index_calc_[well_index].reInit(well);
    }

    this->wellStructureChangedDynamically_ = sim_update.well_structure_changed;
}

template<class Scalar>
Scalar BlackoilWellModelGeneric<Scalar>::
wellPI(const int well_index) const
{
    const auto& pu = this->phase_usage_;
    const auto& pi = this->wellState().well(well_index).productivity_index;

    const auto preferred = this->wells_ecl_[well_index].getPreferredPhase();
    switch (preferred) { // Should really have LIQUID = OIL + WATER here too...
    case Phase::WATER:
        return pu.phase_used[BlackoilPhases::PhaseIndex::Aqua]
            ? pi[pu.phase_pos[BlackoilPhases::PhaseIndex::Aqua]]
            : 0.0;

    case Phase::OIL:
        return pu.phase_used[BlackoilPhases::PhaseIndex::Liquid]
            ? pi[pu.phase_pos[BlackoilPhases::PhaseIndex::Liquid]]
            : 0.0;

    case Phase::GAS:
        return pu.phase_used[BlackoilPhases::PhaseIndex::Vapour]
            ? pi[pu.phase_pos[BlackoilPhases::PhaseIndex::Vapour]]
            : 0.0;

    default:
        throw std::invalid_argument {
            "Unsupported preferred phase " +
            std::to_string(static_cast<int>(preferred))
        };
    }
}

template<class Scalar>
Scalar BlackoilWellModelGeneric<Scalar>::
wellPI(const std::string& well_name) const
{
    auto well_iter = std::find_if(this->wells_ecl_.begin(), this->wells_ecl_.end(),
        [&well_name](const Well& well)
    {
        return well.name() == well_name;
    });

    if (well_iter == this->wells_ecl_.end()) {
        throw std::logic_error { "Could not find well: " + well_name };
    }

    auto well_index = std::distance(this->wells_ecl_.begin(), well_iter);
    return this->wellPI(well_index);
}

template<class Scalar>
bool BlackoilWellModelGeneric<Scalar>::
wasDynamicallyShutThisTimeStep(const int well_index) const
{
    return wasDynamicallyShutThisTimeStep(this->wells_ecl_[well_index].name());
}

template<class Scalar>
bool
BlackoilWellModelGeneric<Scalar>::
wasDynamicallyShutThisTimeStep(const std::string& well_name) const
{
    return this->closed_this_step_.find(well_name) !=
           this->closed_this_step_.end();
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
updateWsolvent(const Group& group,
               const int reportStepIdx,
               const WellState<Scalar>& wellState)
{
    for (const std::string& groupName : group.groups()) {
        const Group& groupTmp = schedule_.getGroup(groupName, reportStepIdx);
        updateWsolvent(groupTmp, reportStepIdx, wellState);
    }

    if (group.isProductionGroup())
        return;

    auto currentGroupControl = this->groupState().injection_control(group.name(), Phase::GAS);
    if( currentGroupControl == Group::InjectionCMode::REIN ) {
        int gasPos = phase_usage_.phase_pos[BlackoilPhases::Vapour];
        const auto& controls = group.injectionControls(Phase::GAS, summaryState_);
        const Group& groupRein = schedule_.getGroup(controls.reinj_group, reportStepIdx);
        Scalar gasProductionRate = WellGroupHelpers<Scalar>::sumWellSurfaceRates(groupRein,
                                                                                 schedule_,
                                                                                 wellState,
                                                                                 reportStepIdx,
                                                                                 gasPos,
                                                                                 /*isInjector*/false);
        Scalar solventProductionRate = WellGroupHelpers<Scalar>::sumSolventRates(groupRein,
                                                                                 schedule_,
                                                                                 wellState,
                                                                                 reportStepIdx,
                                                                                 /*isInjector*/false);

        solventProductionRate = comm_.sum(solventProductionRate);
        gasProductionRate = comm_.sum(gasProductionRate);

        Scalar wsolvent = 0.0;
        if (std::abs(gasProductionRate) > 1e-6)
            wsolvent = solventProductionRate / gasProductionRate;

        setWsolvent(group, reportStepIdx, wsolvent);
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
setWsolvent(const Group& group,
            const int reportStepIdx,
            Scalar wsolvent)
{
    for (const std::string& groupName : group.groups()) {
        const Group& groupTmp = schedule_.getGroup(groupName, reportStepIdx);
        setWsolvent(groupTmp, reportStepIdx, wsolvent);
    }

    for (const std::string& wellName : group.wells()) {
        const auto& wellTmp = schedule_.getWell(wellName, reportStepIdx);
        if (wellTmp.getStatus() == Well::Status::SHUT)
            continue;

        getGenWell(wellName)->setWsolvent(wsolvent);
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
assignWellTargets(data::Wells& wsrpt) const
{
    auto pwInfo = this->local_parallel_well_info_.begin();

    for (const auto& well : this->wells_ecl_) {
        if (! pwInfo++->get().isOwner()) {
            continue;
        }

        // data::Wells is a std::map<>
        auto& limits = wsrpt[well.name()].limits;

        if (well.isProducer()) {
            this->assignProductionWellTargets(well, limits);
        }
        else {
            this->assignInjectionWellTargets(well, limits);
        }
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
assignProductionWellTargets(const Well& well, data::WellControlLimits& limits) const
{
    using Item = data::WellControlLimits::Item;

    const auto ctrl = well.productionControls(this->summaryState());

    limits
        .set(Item::Bhp, ctrl.bhp_limit)
        .set(Item::OilRate, ctrl.oil_rate)
        .set(Item::WaterRate, ctrl.water_rate)
        .set(Item::GasRate, ctrl.gas_rate)
        .set(Item::ResVRate, ctrl.resv_rate)
        .set(Item::LiquidRate, ctrl.liquid_rate);
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
assignInjectionWellTargets(const Well& well, data::WellControlLimits& limits) const
{
    using Item = data::WellControlLimits::Item;

    const auto ctrl = well.injectionControls(this->summaryState());

    limits
        .set(Item::Bhp, ctrl.bhp_limit)
        .set(Item::ResVRate, ctrl.reservoir_rate);

    if (ctrl.injector_type == InjectorType::MULTI) {
        // Not supported
        return;
    }

    auto rateItem = Item::WaterRate;
    if (ctrl.injector_type == InjectorType::GAS) {
        rateItem = Item::GasRate;
    }
    else if (ctrl.injector_type == InjectorType::OIL) {
        rateItem = Item::OilRate;
    }

    limits.set(rateItem, ctrl.surface_rate);
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
assignShutConnections(data::Wells& wsrpt,
                      const int reportStepIndex) const
{
    auto wellID = 0;

    for (const auto& well : this->wells_ecl_) {
        auto& xwel = wsrpt[well.name()]; // data::Wells is a std::map<>

        xwel.dynamicStatus = this->schedule()
            .getWell(well.name(), reportStepIndex).getStatus();

        const auto wellIsOpen = xwel.dynamicStatus == Well::Status::OPEN;
        auto skip = [wellIsOpen](const Connection& conn)
        {
            return wellIsOpen && (conn.state() != Connection::State::SHUT);
        };

        if (this->wellTestState().well_is_closed(well.name()) &&
            !this->wasDynamicallyShutThisTimeStep(wellID))
        {
            xwel.dynamicStatus = well.getAutomaticShutIn()
                ? Well::Status::SHUT : Well::Status::STOP;
        }

        auto& xcon = xwel.connections;
        for (const auto& conn : well.getConnections()) {
            if (skip(conn)) {
                continue;
            }

            auto& xc = xcon.emplace_back();
            xc.index = conn.global_index();
            xc.pressure = xc.reservoir_rate = 0.0;

            xc.effective_Kh = conn.Kh();
            xc.trans_factor = conn.CF();
            xc.d_factor = conn.dFactor();
        }

        ++wellID;
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
assignGroupControl(const Group& group,
                   data::GroupData& gdata) const
{
    const auto& gname     = group.name();
    const auto  grup_type = group.getGroupType();
    auto&       cgc       = gdata.currentControl;

    cgc.currentProdConstraint = Group::ProductionCMode::NONE;

    cgc.currentGasInjectionConstraint =
    cgc.currentWaterInjectionConstraint = Group::InjectionCMode::NONE;

    if (this->groupState().has_production_control(gname)) {
        cgc.currentProdConstraint = this->groupState().production_control(gname);
    }

    if ((grup_type == ::Opm::Group::GroupType::INJECTION) ||
        (grup_type == ::Opm::Group::GroupType::MIXED))
    {
        if (this->groupState().has_injection_control(gname, Phase::WATER)) {
            cgc.currentWaterInjectionConstraint = this->groupState().injection_control(gname, Phase::WATER);
        }

        if (this->groupState().has_injection_control(gname, Phase::GAS)) {
            cgc.currentGasInjectionConstraint = this->groupState().injection_control(gname, Phase::GAS);
        }
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
assignGroupValues(const int                               reportStepIdx,
                  std::map<std::string, data::GroupData>& gvalues) const
{
    const auto groupGuideRates =
        BlackoilWellModelGuideRates(*this).calculateAllGroupGuideRates(reportStepIdx);

    for (const auto& gname : schedule_.groupNames(reportStepIdx)) {
        const auto& grup = schedule_.getGroup(gname, reportStepIdx);

        auto& gdata = gvalues[gname];
        this->assignGroupControl(grup, gdata);
        BlackoilWellModelGuideRates(*this).assignGroupGuideRates(grup, groupGuideRates, gdata);
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
assignNodeValues(std::map<std::string, data::NodeData>& nodevalues,
                 const int reportStepIdx) const
{
    nodevalues.clear();
    if (reportStepIdx < 0) return;

    for (const auto& [node, pressure] : node_pressures_) {
        nodevalues.emplace(node, data::NodeData{pressure});
        // Assign node values of well groups to GPR:WELLNAME
        const auto& sched = schedule();
        if (!sched.hasGroup(node, reportStepIdx)) {
            continue;
        }
        const auto& group = sched.getGroup(node, reportStepIdx);
        for (const std::string& wellname : group.wells()) {
            nodevalues.emplace(wellname, data::NodeData{pressure});
        }
    }

    const auto& network = schedule()[reportStepIdx].network();
    if (!network.active()) {
        return;
    }

    auto converged_pressures = WellGroupHelpers<Scalar>::computeNetworkPressures(network,
                                                                                 this->wellState(),
                                                                                 this->groupState(),
                                                                                 *(vfp_properties_->getProd()),
                                                                                 schedule(),
                                                                                 reportStepIdx);
    for (const auto& [node, converged_pressure] : converged_pressures) {
        auto it = nodevalues.find(node);
        assert(it != nodevalues.end() );
        it->second.converged_pressure = converged_pressure;
        // Assign node values of group to GPR:WELLNAME
        const auto& sched = schedule();
        if (!sched.hasGroup(node, reportStepIdx)) {
            continue;
        }
        const auto& group = sched.getGroup(node, reportStepIdx);
        for (const std::string& wellname : group.wells()) {
            auto it2 = nodevalues.find(wellname);
            assert(it2 != nodevalues.end());
            it2->second.converged_pressure = converged_pressure;
        }
    }
}

template<class Scalar>
data::GroupAndNetworkValues
BlackoilWellModelGeneric<Scalar>::
groupAndNetworkData(const int reportStepIdx) const
{
    auto grp_nwrk_values = data::GroupAndNetworkValues{};

    this->assignGroupValues(reportStepIdx, grp_nwrk_values.groupData);
    this->assignNodeValues(grp_nwrk_values.nodeData, reportStepIdx - 1); // Schedule state info at previous step

    return grp_nwrk_values;
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
updateAndCommunicateGroupData(const int reportStepIdx,
                              const int iterationIdx)
{
    const Group& fieldGroup = schedule().getGroup("FIELD", reportStepIdx);
    const int nupcol = schedule()[reportStepIdx].nupcol();

    // This builds some necessary lookup structures, so it must be called
    // before we copy to well_state_nupcol_.
    this->wellState().updateGlobalIsGrup(comm_);

    if (iterationIdx < nupcol) {
        this->updateNupcolWGState();
    }

    auto& well_state = this->wellState();
    const auto& well_state_nupcol = this->nupcolWellState();
    // the group target reduction rates needs to be update since wells may have switched to/from GRUP control
    // The group target reduction does not honor NUPCOL.
    std::vector<Scalar> groupTargetReduction(numPhases(), 0.0);
    WellGroupHelpers<Scalar>::updateGroupTargetReduction(fieldGroup,
                                                         schedule(),
                                                         reportStepIdx,
                                                         /*isInjector*/ false,
                                                         phase_usage_,
                                                         guideRate_,
                                                         well_state,
                                                         this->groupState(),
                                                         groupTargetReduction);
    std::vector<Scalar> groupTargetReductionInj(numPhases(), 0.0);
    WellGroupHelpers<Scalar>::updateGroupTargetReduction(fieldGroup,
                                                         schedule(),
                                                         reportStepIdx,
                                                         /*isInjector*/ true,
                                                         phase_usage_,
                                                         guideRate_,
                                                         well_state,
                                                         this->groupState(),
                                                         groupTargetReductionInj);

    WellGroupHelpers<Scalar>::updateREINForGroups(fieldGroup,
                                                  schedule(),
                                                  reportStepIdx,
                                                  phase_usage_,
                                                  summaryState_,
                                                  well_state_nupcol,
                                                  this->groupState(),
                                                  comm_.rank() == 0);
    WellGroupHelpers<Scalar>::updateVREPForGroups(fieldGroup,
                                                  schedule(),
                                                  reportStepIdx,
                                                  well_state_nupcol,
                                                  this->groupState());

    WellGroupHelpers<Scalar>::updateReservoirRatesInjectionGroups(fieldGroup,
                                                                  schedule(),
                                                                  reportStepIdx,
                                                                  well_state_nupcol,
                                                                  this->groupState());
    WellGroupHelpers<Scalar>::updateSurfaceRatesInjectionGroups(fieldGroup,
                                                                schedule(),
                                                                reportStepIdx,
                                                                well_state_nupcol,
                                                                this->groupState());

    WellGroupHelpers<Scalar>::updateGroupProductionRates(fieldGroup,
                                                         schedule(),
                                                         reportStepIdx,
                                                         well_state_nupcol,
                                                         this->groupState());

    // We use the rates from the previous time-step to reduce oscillations
    WellGroupHelpers<Scalar>::updateWellRates(fieldGroup,
                                              schedule(),
                                              reportStepIdx,
                                              this->prevWellState(),
                                              well_state);

    // Set ALQ for off-process wells to zero
    for (const auto& wname : schedule().wellNames(reportStepIdx)) {
        const bool is_producer = schedule().getWell(wname, reportStepIdx).isProducer();
        const bool not_on_this_process = !well_state.has(wname);
        if (is_producer && not_on_this_process) {
            well_state.setALQ(wname, 0.0);
        }
    }

    well_state.communicateGroupRates(comm_);
    this->groupState().communicate_rates(comm_);
}

template<class Scalar>
bool BlackoilWellModelGeneric<Scalar>::
hasTHPConstraints() const
{
    return BlackoilWellModelConstraints(*this).hasTHPConstraints();
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
updateNetworkActiveState(const int report_step) {
    const auto& network = schedule()[report_step].network();
    if (!network.active()) {
        this->network_active_ = false;
        return;
    }

    bool network_active = false;
    for (const auto& well : well_container_generic_) {
        const bool is_partof_network = network.has_node(well->wellEcl().groupName());
        const bool prediction_mode = well->wellEcl().predictionMode();
        if (is_partof_network && prediction_mode) {
            network_active = true;
            break;
        }
    }
    this->network_active_ = comm_.max(network_active);
}

template<class Scalar>
bool BlackoilWellModelGeneric<Scalar>::
needPreStepNetworkRebalance(const int report_step) const
{
    const auto& network = schedule()[report_step].network();
    bool network_rebalance_necessary = false;
    for (const auto& well : well_container_generic_) {
        const bool is_partof_network = network.has_node(well->wellEcl().groupName());
        // TODO: we might find more relevant events to be included here (including network change events?)
        const auto& events = this->wellState().well(well->indexOfWell()).events;
        if (is_partof_network && events.hasEvent(ScheduleEvents::WELL_STATUS_CHANGE)) {
            network_rebalance_necessary = true;
            break;
        }
    }
    network_rebalance_necessary = comm_.max(network_rebalance_necessary);
    return network_rebalance_necessary;
}

template<class Scalar>
bool BlackoilWellModelGeneric<Scalar>::
forceShutWellByName(const std::string& wellname,
                    const double simulation_time)
{
    // Only add the well to the closed list on the
    // process that owns it.
    int well_was_shut = 0;
    for (const auto& well : well_container_generic_) {
        if (well->name() == wellname) {
            wellTestState().close_well(wellname, WellTestConfig::Reason::PHYSICAL, simulation_time);
            well_was_shut = 1;
            break;
        }
    }

    // Communicate across processes if a well was shut.
    well_was_shut = comm_.max(well_was_shut);

    // the wellTesteState is updated between timesteps and we also need to update the privous WGstate
    if(well_was_shut)
        this->commitWGState();

    // Only log a message on the output rank.
    if (terminal_output_ && well_was_shut) {
        const std::string msg = "Well " + wellname
            + " will be shut because it fails to converge.";
        OpmLog::info(msg);
    }

    return (well_was_shut == 1);
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
inferLocalShutWells()
{
    this->local_shut_wells_.clear();

    const auto nw = this->numLocalWells();

    auto used = std::vector<bool>(nw, false);
    for (const auto& wellPtr : this->well_container_generic_) {
        used[wellPtr->indexOfWell()] = true;
    }

    for (auto wellID = 0; wellID < nw; ++wellID) {
        if (! used[wellID]) {
            this->local_shut_wells_.push_back(wellID);
        }
    }
}

template<class Scalar>
Scalar BlackoilWellModelGeneric<Scalar>::
updateNetworkPressures(const int reportStepIdx)
{
    // Get the network and return if inactive (no wells in network at this time)
    const auto& network = schedule()[reportStepIdx].network();
    if (!network.active()) {
        return 0.0;
    }

    const auto previous_node_pressures = node_pressures_;

    node_pressures_ = WellGroupHelpers<Scalar>::computeNetworkPressures(network,
                                                                        this->wellState(),
                                                                        this->groupState(),
                                                                        *(vfp_properties_->getProd()),
                                                                        schedule(),
                                                                        reportStepIdx);

    // here, the network imbalance is the difference between the previous nodal pressure and the new nodal pressure
    Scalar network_imbalance = 0.;
    if (!this->networkActive())
        return network_imbalance;

    if (!previous_node_pressures.empty()) {
        for (const auto& [name, new_pressure]: node_pressures_) {
            if (previous_node_pressures.count(name) <= 0) {
                if (std::abs(new_pressure) > network_imbalance) {
                    network_imbalance = std::abs(new_pressure);
                }
                continue;
            }
            const auto pressure = previous_node_pressures.at(name);
            const Scalar change = (new_pressure - pressure);
            if (std::abs(change) > network_imbalance) {
                network_imbalance = std::abs(change);
            }
            // we dampen the amount of the nodal pressure can change during one iteration
            // due to the fact our nodal pressure calculation is somewhat explicit
            // TODO: the following parameters are subject to adjustment for optimization purpose
            constexpr Scalar upper_update_bound = 5.0 * unit::barsa;
            // relative dampening factor based on update value
            constexpr Scalar damping_factor = 0.1;
            const Scalar damped_change = std::min(damping_factor * std::abs(change), upper_update_bound);
            const Scalar sign = change > 0 ? 1. : -1.;
            node_pressures_[name] = pressure + sign * damped_change;
        }
    } else {
        for (const auto& [name, pressure]: node_pressures_) {
            if (std::abs(pressure) > network_imbalance) {
                network_imbalance = std::abs(pressure);
            }
        }
    }

    for (auto& well : well_container_generic_) {

        // Producers only, since we so far only support the
        // "extended" network model (properties defined by
        // BRANPROP and NODEPROP) which only applies to producers.
        if (well->isProducer() && well->wellEcl().predictionMode()) {
            const auto it = node_pressures_.find(well->wellEcl().groupName());
            if (it != node_pressures_.end()) {
                // The well belongs to a group with has a network pressure constraint,
                // set the dynamic THP constraint of the well accordingly.
                const Scalar new_limit = it->second;
                well->setDynamicThpLimit(new_limit);
                SingleWellState<Scalar>& ws = this->wellState()[well->indexOfWell()];
                const bool thp_is_limit = ws.production_cmode == Well::ProducerCMode::THP;
                // TODO: not sure why the thp is NOT updated properly elsewhere
                if (thp_is_limit) {
                    ws.thp = well->getTHPConstraint(summaryState_);
                }
            }
        }
    }
    return network_imbalance;
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
calculateEfficiencyFactors(const int reportStepIdx)
{
    for (auto& well : well_container_generic_) {
        const Well& wellEcl = well->wellEcl();
        Scalar well_efficiency_factor = wellEcl.getEfficiencyFactor();
        WellGroupHelpers<Scalar>::accumulateGroupEfficiencyFactor(schedule().getGroup(wellEcl.groupName(),
                                                                                      reportStepIdx),
                                                                  schedule(),
                                                                  reportStepIdx,
                                                                  well_efficiency_factor);
        well->setWellEfficiencyFactor(well_efficiency_factor);
    }
}

template<class Scalar>
WellInterfaceGeneric<Scalar>*
BlackoilWellModelGeneric<Scalar>::
getGenWell(const std::string& well_name)
{
    // finding the iterator of the well in wells_ecl
    auto well = std::find_if(well_container_generic_.begin(),
                             well_container_generic_.end(),
                                [&well_name](const WellInterfaceGeneric<Scalar>* elem)->bool {
                                     return elem->name() == well_name;
                                 });

    assert(well != well_container_generic_.end());

    return *well;
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
setRepRadiusPerfLength()
{
    for (const auto& well : well_container_generic_) {
        well->setRepRadiusPerfLength();
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
gliftDebug(const std::string& msg,
           DeferredLogger& deferred_logger) const
{
    if (this->glift_debug && this->terminal_output_) {
        const std::string message = fmt::format(
            "  GLIFT (DEBUG) : BlackoilWellModel : {}", msg);
        deferred_logger.info(message);
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
gliftDebugShowALQ(DeferredLogger& deferred_logger)
{
    for (auto& well : this->well_container_generic_) {
        if (well->isProducer()) {
            auto alq = this->wellState().getALQ(well->name());
            const std::string msg = fmt::format("ALQ_REPORT : {} : {}",
                                                well->name(), alq);
            gliftDebug(msg, deferred_logger);
        }
    }
}

// If a group has any production rate constraints, and/or a limit
// on its total rate of lift gas supply,  allocate lift gas
// preferentially to the wells that gain the most benefit from
// it. Lift gas increments are allocated in turn to the well that
// currently has the largest weighted incremental gradient. The
// procedure takes account of any limits on the group production
// rate or lift gas supply applied to any level of group.
template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
gasLiftOptimizationStage2(DeferredLogger& deferred_logger,
                          GLiftProdWells& prod_wells,
                          GLiftOptWells& glift_wells,
                          GasLiftGroupInfo<Scalar>& group_info,
                          GLiftWellStateMap& glift_well_state_map,
                          const int episodeIndex)
{
    GasLiftStage2 glift {episodeIndex,
                         comm_,
                         schedule_,
                         summaryState_,
                         deferred_logger,
                         this->wellState(),
                         this->groupState(),
                         prod_wells,
                         glift_wells,
                         group_info,
                         glift_well_state_map,
                         this->glift_debug
    };
    glift.runOptimize();
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
updateWellPotentials(const int reportStepIdx,
                     const bool onlyAfterEvent,
                     const SummaryConfig& summaryConfig,
                     DeferredLogger& deferred_logger)
{
    auto well_state_copy = this->wellState();

    const bool write_restart_file = schedule().write_rst_file(reportStepIdx);
    auto exc_type = ExceptionType::NONE;
    std::string exc_msg;
    std::size_t widx = 0;
    for (const auto& well : well_container_generic_) {
        const bool needed_for_summary =
                ((summaryConfig.hasSummaryKey( "WWPI:" + well->name()) ||
                  summaryConfig.hasSummaryKey( "WOPI:" + well->name()) ||
                  summaryConfig.hasSummaryKey( "WGPI:" + well->name())) && well->isInjector()) ||
                ((summaryConfig.hasKeyword( "GWPI") ||
                  summaryConfig.hasKeyword( "GOPI") ||
                  summaryConfig.hasKeyword( "GGPI")) && well->isInjector()) ||
                ((summaryConfig.hasKeyword( "FWPI") ||
                  summaryConfig.hasKeyword( "FOPI") ||
                  summaryConfig.hasKeyword( "FGPI")) && well->isInjector()) ||
                ((summaryConfig.hasSummaryKey( "WWPP:" + well->name()) ||
                  summaryConfig.hasSummaryKey( "WOPP:" + well->name()) ||
                  summaryConfig.hasSummaryKey( "WGPP:" + well->name())) && well->isProducer()) ||
                ((summaryConfig.hasKeyword( "GWPP") ||
                  summaryConfig.hasKeyword( "GOPP") ||
                  summaryConfig.hasKeyword( "GGPP")) && well->isProducer()) ||
                ((summaryConfig.hasKeyword( "FWPP") ||
                  summaryConfig.hasKeyword( "FOPP") ||
                  summaryConfig.hasKeyword( "FGPP")) && well->isProducer());

        // At the moment, the following events are considered
        // for potentials update
        const uint64_t effective_events_mask = ScheduleEvents::WELL_STATUS_CHANGE
                                             + ScheduleEvents::COMPLETION_CHANGE
                                             + ScheduleEvents::WELL_PRODUCTIVITY_INDEX
                                             + ScheduleEvents::WELL_WELSPECS_UPDATE
                                             + ScheduleEvents::WELLGROUP_EFFICIENCY_UPDATE
                                             + ScheduleEvents::NEW_WELL
                                             + ScheduleEvents::PRODUCTION_UPDATE
                                             + ScheduleEvents::INJECTION_UPDATE;
        const auto& events = schedule()[reportStepIdx].wellgroup_events();
        const bool event = events.hasEvent(well->name(), ScheduleEvents::ACTIONX_WELL_EVENT) ||
                           (report_step_starts_ && events.hasEvent(well->name(), effective_events_mask));
        const bool needPotentialsForGuideRates = well->underPredictionMode() && (!onlyAfterEvent || event);
        const bool needPotentialsForOutput = !onlyAfterEvent && (needed_for_summary || write_restart_file);
        const bool compute_potential = needPotentialsForOutput || needPotentialsForGuideRates;
        if (compute_potential)
        {
            this->computePotentials(widx, well_state_copy, exc_msg, exc_type, deferred_logger);
        }
        ++widx;
    }
    logAndCheckForProblemsAndThrow(deferred_logger, exc_type,
                                   "updateWellPotentials() failed: " + exc_msg,
                                   terminal_output_, comm_);
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
runWellPIScaling(const int reportStepIdx,
                 DeferredLogger& local_deferredLogger)
{
    if (this->last_run_wellpi_.has_value() && (*this->last_run_wellpi_ == reportStepIdx)) {
        // We've already run WELPI scaling for this report step.  Most
        // common for the very first report step.  Don't redo WELPI scaling.
        return;
    }

    auto hasWellPIEvent = [this, reportStepIdx](const int well_index) -> bool
    {
        return this->schedule()[reportStepIdx].wellgroup_events()
            .hasEvent(this->wells_ecl_[well_index].name(),
                      ScheduleEvents::Events::WELL_PRODUCTIVITY_INDEX);
    };

    auto updateEclWell = [this, reportStepIdx](const int well_index) -> void
    {
        const auto& schedule = this->schedule();
        const auto& wname = this->wells_ecl_[well_index].name();
        this->wells_ecl_[well_index] = schedule.getWell(wname, reportStepIdx);

        const auto& well = this->wells_ecl_[well_index];
        auto& pd     = this->well_perf_data_[well_index];
        auto  pdIter = pd.begin();
        for (const auto& conn : well.getConnections()) {
            if (conn.state() != Connection::State::SHUT) {
                pdIter->connection_transmissibility_factor = conn.CF();
                ++pdIter;
            }
        }
        auto& ws = this->wellState().well(well_index);
        ws.reset_connection_factors(pd);
        this->prod_index_calc_[well_index].reInit(well);
    };

    auto rescaleWellPI =
        [this, reportStepIdx](const int    well_index,
                              const Scalar newWellPI) -> void
    {
        const auto& wname = this->wells_ecl_[well_index].name();

        schedule_.applyWellProdIndexScaling(wname, reportStepIdx, newWellPI);
    };

    // Minimal well setup to compute PI/II values
    {
        auto saved_previous_wgstate = this->prevWGState();
        this->commitWGState();

        this->createWellContainer(reportStepIdx);
        this->inferLocalShutWells();

        this->initWellContainer(reportStepIdx);

        this->calculateProductivityIndexValues(local_deferredLogger);
        this->calculateProductivityIndexValuesShutWells(reportStepIdx, local_deferredLogger);

        this->commitWGState(std::move(saved_previous_wgstate));
    }

    const auto nw = this->numLocalWells();
    for (auto wellID = 0*nw; wellID < nw; ++wellID) {
        if (hasWellPIEvent(wellID)) {
            rescaleWellPI(wellID, this->wellPI(wellID));
            updateEclWell(wellID);
        }
    }

    this->last_run_wellpi_ = reportStepIdx;
}

template<class Scalar>
bool BlackoilWellModelGeneric<Scalar>::
shouldBalanceNetwork(const int reportStepIdx, const int iterationIdx) const
{
    // if network is not active, we do not need to balance the network
    const auto& network = schedule()[reportStepIdx].network();
    if (!network.active()) {
        return false;
    }

    const auto& balance = schedule()[reportStepIdx].network_balance();
    if (balance.mode() == Network::Balance::CalcMode::TimeStepStart) {
        return iterationIdx == 0;
    } else if (balance.mode() == Network::Balance::CalcMode::NUPCOL) {
        const int nupcol = schedule()[reportStepIdx].nupcol();
        return iterationIdx < nupcol;
    } else {
        // We do not support any other rebalancing modes,
        // i.e. TimeInterval based rebalancing is not available.
        // This should be warned about elsewhere, so we choose to
        // avoid spamming with a warning here.
        return false;
    }
}

template<class Scalar>
std::vector<int> BlackoilWellModelGeneric<Scalar>::
getCellsForConnections(const Well& well) const
{
    std::vector<int> wellCells;
    // All possible connections of the well
    const auto& connectionSet = well.getConnections();
    wellCells.reserve(connectionSet.size());

    for (const auto& connection : connectionSet)
    {
        int compressed_idx = compressedIndexForInterior(connection.global_index());
        if (compressed_idx >= 0) { // Ignore connections in inactive/remote cells.
            wellCells.push_back(compressed_idx);
        }
    }

    return wellCells;
}

template<class Scalar>
std::vector<std::string> BlackoilWellModelGeneric<Scalar>::
getWellsForTesting(const int timeStepIdx,
                   const double simulationTime)
{
  const auto& wtest_config = schedule()[timeStepIdx].wtest_config();
  if (!wtest_config.empty()) { // there is a WTEST request
      return wellTestState().test_wells(wtest_config, simulationTime);
  } else
      return {};
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
assignMassGasRate(data::Wells& wsrpt,
                  const Scalar& gasDensity) const
{
    using rt = data::Rates::opt;
    for (auto& wrpt : wsrpt) {
        auto& well_rates = wrpt.second.rates;
        const auto w_mass_rate = well_rates.get(rt::gas, 0.0) * gasDensity;
        well_rates.set(rt::mass_gas, w_mass_rate);
    }
}


template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
assignWellTracerRates(data::Wells& wsrpt,
                      const WellTracerRates& wellTracerRates) const
{
    if (wellTracerRates.empty())
        return; // no tracers

    for (const auto& wTR : wellTracerRates) {
        std::string wellName = wTR.first.first;
        auto xwPos = wsrpt.find(wellName);
        if (xwPos == wsrpt.end()) { // No well results.
            continue;
        }
        std::string tracerName = wTR.first.second;
        Scalar rate = wTR.second;
        xwPos->second.rates.set(data::Rates::opt::tracer, rate, tracerName);
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
assignMswTracerRates(data::Wells& wsrpt,
                     const MswTracerRates& mswTracerRates) const
{
    if (mswTracerRates.empty())
        return;
    
    for (const auto& mswTR : mswTracerRates) {
        std::string wellName = std::get<0>(mswTR.first);
        auto xwPos = wsrpt.find(wellName);
        if (xwPos == wsrpt.end()) { // No well results.
            continue;
        }
        std::string tracerName = std::get<1>(mswTR.first);
        std::size_t segNumber = std::get<2>(mswTR.first);
        Scalar rate = mswTR.second;

        auto& wData = xwPos->second;
        auto segPos = wData.segments.find(segNumber);
        if (segPos != wData.segments.end()) {
            auto& segment = segPos->second;
            segment.rates.set(data::Rates::opt::tracer, rate, tracerName);
        }
    }
}

template<class Scalar>
std::vector<std::vector<int>> BlackoilWellModelGeneric<Scalar>::
getMaxWellConnections() const
{
    std::vector<std::vector<int>> wells;

    auto schedule_wells = schedule().getWellsatEnd();
    schedule_wells.erase(std::remove_if(schedule_wells.begin(), schedule_wells.end(), not_on_process_), schedule_wells.end());
    wells.reserve(schedule_wells.size());

    auto possibleFutureConnections = schedule().getPossibleFutureConnections();
#if HAVE_MPI
    // Communicate Map to other processes, since it is only available on rank 0
    Parallel::MpiSerializer ser(comm_);
    ser.broadcast(possibleFutureConnections);
#endif
    // initialize the additional cell connections introduced by wells.
    for (const auto& well : schedule_wells)
    {
        std::vector<int> compressed_well_perforations = this->getCellsForConnections(well);

        const auto possibleFutureConnectionSetIt = possibleFutureConnections.find(well.name());
        if (possibleFutureConnectionSetIt != possibleFutureConnections.end()) {
            for (auto& global_index : possibleFutureConnectionSetIt->second) {
                int compressed_idx = compressedIndexForInterior(global_index);
                if (compressed_idx >= 0) { // Ignore connections in inactive/remote cells.
                    compressed_well_perforations.push_back(compressed_idx);
                }
            }
        }
        // also include wells with no perforations in case
        std::sort(compressed_well_perforations.begin(),
                  compressed_well_perforations.end());

        wells.push_back(compressed_well_perforations);
    }
    return wells;
}

template<class Scalar>
int BlackoilWellModelGeneric<Scalar>::numLocalWellsEnd() const
{
    auto w = schedule().getWellsatEnd();
    w.erase(std::remove_if(w.begin(), w.end(), not_on_process_), w.end());
    return w.size();
}

template<class Scalar>
int BlackoilWellModelGeneric<Scalar>::numLocalNonshutWells() const
{
    return well_container_generic_.size();
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::initInjMult()
{
    for (auto& well : this->well_container_generic_) {
        if (well->isInjector() && well->wellEcl().getInjMultMode() != Well::InjMultMode::NONE) {
            const auto& ws = this->wellState().well(well->indexOfWell());
            const auto& perf_data = ws.perf_data;

            auto& values = this->prev_inj_multipliers_[well->name()];
            if (values.empty()) {
                values.assign(perf_data.size(), 1.0);
            }
            well->initInjMult(values);
        }
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
updateFiltrationParticleVolume(const double dt,
                               const std::size_t water_index)
{
    for (auto& well : this->well_container_generic_) {
        if (well->isInjector()) {
            const Scalar conc = well->wellEcl().evalFilterConc(this->summaryState_);
            if (conc > 0.) {
                auto fc = this->filter_cake_
                        .emplace(std::piecewise_construct,
                                 std::forward_as_tuple(well->name()),
                                 std::tuple{});

                fc.first->second.updateFiltrationParticleVolume(*well, dt, conc, water_index,
                                                                this->wellState());
            }
        }
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
updateInjMult(DeferredLogger& deferred_logger)
{
    for (const auto& well : this->well_container_generic_) {
        if (well->isInjector() && well->wellEcl().getInjMultMode() != Well::InjMultMode::NONE) {
            well->updateInjMult(this->prev_inj_multipliers_[well->name()], deferred_logger);
        }
    }
}

template<class Scalar>
void BlackoilWellModelGeneric<Scalar>::
updateInjFCMult(DeferredLogger& deferred_logger)
{
    for (auto& well : this->well_container_generic_) {
        if (well->isInjector()) {
            const auto it = filter_cake_.find(well->name());
            if (it != filter_cake_.end()) {
                it->second.updateInjFCMult(*well, this->wellState(), deferred_logger);
                well->updateFilterCakeMultipliers(it->second.multipliers());
            }
        }
    }
}

template class BlackoilWellModelGeneric<double>;

#if FLOW_INSTANTIATE_FLOAT
template class BlackoilWellModelGeneric<float>;
#endif

}