CharacteristicEvolution.hpp

// Distributed under the MIT License.
// See LICENSE.txt for details.

#pragma once

#include <type_traits>

#include "DataStructures/VariablesTag.hpp"
#include "Evolution/Systems/Cce/Actions/BoundaryComputeAndSendToEvolution.hpp"
#include "Evolution/Systems/Cce/Actions/CalculateScriInputs.hpp"
#include "Evolution/Systems/Cce/Actions/CharacteristicEvolutionBondiCalculations.hpp"
#include "Evolution/Systems/Cce/Actions/FilterSwshVolumeQuantity.hpp"
#include "Evolution/Systems/Cce/Actions/InitializeCharacteristicEvolutionScri.hpp"
#include "Evolution/Systems/Cce/Actions/InitializeCharacteristicEvolutionTime.hpp"
#include "Evolution/Systems/Cce/Actions/InitializeCharacteristicEvolutionVariables.hpp"
#include "Evolution/Systems/Cce/Actions/InitializeFirstHypersurface.hpp"
#include "Evolution/Systems/Cce/Actions/InsertInterpolationScriData.hpp"
#include "Evolution/Systems/Cce/Actions/RequestBoundaryData.hpp"
#include "Evolution/Systems/Cce/Actions/ScriObserveInterpolated.hpp"
#include "Evolution/Systems/Cce/Actions/TimeManagement.hpp"
#include "Evolution/Systems/Cce/Actions/UpdateGauge.hpp"
#include "Evolution/Systems/Cce/LinearSolve.hpp"
#include "Evolution/Systems/Cce/PreSwshDerivatives.hpp"
#include "Evolution/Systems/Cce/PrecomputeCceDependencies.hpp"
#include "Evolution/Systems/Cce/ScriPlusValues.hpp"
#include "Evolution/Systems/Cce/SwshDerivatives.hpp"
#include "IO/Observer/ObserverComponent.hpp"
#include "Parallel/Actions/TerminatePhase.hpp"
#include "Parallel/ConstGlobalCache.hpp"
#include "ParallelAlgorithms/Actions/MutateApply.hpp"
#include "ParallelAlgorithms/Initialization/Actions/RemoveOptionsAndTerminatePhase.hpp"
#include "Time/Actions/AdvanceTime.hpp"
#include "Time/Actions/RecordTimeStepperData.hpp"
#include "Time/Actions/UpdateU.hpp"
#include "Utilities/TMPL.hpp"

namespace Cce {

/*!
 * \brief The component for handling the CCE evolution and waveform output.
 *
 * \details The \ref DataBoxGroup associated with the CharacteristicEvolution
 * will contain many spin-weighted volume tags associated with the ongoing CCE
 * computation, as well as storage for the boundary values and quantities
 * related to managing the evolution.
 *
 * Metavariables requirements:
 * - Phases:
 *  - `Initialization`
 *  - `Evolve`
 * - Type aliases:
 *  - `evolved_coordinates_variables_tag`: A `Tags::Variables` with real-valued
 * tensors associated with coordinates that must be evolved.
 *  - `evolved_swsh_tag`: The spin-weighted quantity to be evolved (typically
 * `BondiJ`).
 *  - `evolved_swsh_dt_tag`: The spin-weighed quantity associated that is to act
 * as the time derivative to evolve `evolved_swsh_tag` (typically `BondiH`).
 *  - `cce_boundary_communication_tags`: A typelist of tags that will be
 * communicated between the worldtube boundary component and the extraction
 * component (typically
 * `Cce::Tags::characteristic_worldtube_boundary_tags<Tags::BoundaryValue>`)
 *  - `cce_gauge_boundary_tags`: A typelist of tags that will be derived via
 * `GaugeAdjustedBoundaryValue` and corresponding gauge utilities
 *  - `cce_integrand_tags`: A typelist of tags needed as inputs to the
 * linear solve. Obtainable from the metafunction
 * `Cce::integrand_terms_to_compute_for_bondi_variable`.
 *  - `cce_integration_independent_tags`: A typelist of tags that are to be
 * computed and stored for each hypersurface iteration, but have no dependencies
 * on the intermediate hypersurface steps (typically
 * `Cce::pre_computation_steps`).
 *  - `cce_temporary_equations_tags`: A typelist of temporary buffers maintained
 * for intermediate steps in the integrand equations. Obtainable from the
 * metafunction `Cce::integrand_terms_to_compute_for_bondi_variable`.
 *  - `cce_pre_swsh_derivatives_tags`: A typelist of inputs to spin-weighted
 * derivative calculations to compute and cache for intermediate steps of the
 * CCE calculation. (typically `Cce::all_pre_swsh_derivative_tags`)
 *  - `cce_swsh_derivative_tags`: A typelist of spin-weighted derivatives to
 * compute and cache for intermediate steps of the CCE calculation. (typically
 * `Cce::all_swsh_derivative_tags`)
 *  - `cce_transform_buffer_tags`: A typelist of spin-weighted spherical
 * harmonic transform modes used to compute the spin-weighted derivatives in the
 * modal representation. (typically `Cce::all_transform_buffer_tags`).
 *  - `cce_angular_coordinate_tags`: A typelist of real-valued angular
 * coordinates that are not evolved.
 *  - `cce_scri_tags`: the tags of quantities to compute at scri+
 *  - `cce_hypersurface_initialization`: a mutator (for use with
 * `::Actions::MutateApply`) that is used to compute the initial hypersurface
 * data from the boundary data.
 */
template <class Metavariables>
struct CharacteristicEvolution {
  using chare_type = Parallel::Algorithms::Singleton;
  using metavariables = Metavariables;

  using initialize_action_list =
      tmpl::list<Actions::InitializeCharacteristicEvolutionVariables,
                 Actions::InitializeCharacteristicEvolutionTime,
                 Actions::InitializeCharacteristicEvolutionScri,
                 Actions::RequestBoundaryData<
                     typename Metavariables::cce_boundary_component,
                     CharacteristicEvolution<Metavariables>>,
                 Actions::ReceiveWorldtubeData<Metavariables>,
                 Actions::InitializeFirstHypersurface,
                 Initialization::Actions::RemoveOptionsAndTerminatePhase>;

  using initialization_tags =
      Parallel::get_initialization_tags<initialize_action_list>;

  // the list of actions that occur for each of the hypersurface-integrated
  // Bondi tags
  template <typename BondiTag>
  using hypersurface_computation = tmpl::list<
      ::Actions::MutateApply<GaugeAdjustedBoundaryValue<BondiTag>>,
      Actions::CalculateIntegrandInputsForTag<BondiTag>,
      tmpl::transform<integrand_terms_to_compute_for_bondi_variable<BondiTag>,
                      tmpl::bind<::Actions::MutateApply,
                                 tmpl::bind<ComputeBondiIntegrand, tmpl::_1>>>,
      ::Actions::MutateApply<
          RadialIntegrateBondi<Tags::EvolutionGaugeBoundaryValue, BondiTag>>,
      // Once we finish the U computation, we need to update all the quantities
      // that depend on the time derivative of the gauge
      tmpl::conditional_t<
          cpp17::is_same_v<BondiTag, Tags::BondiU>,
          tmpl::list<
              ::Actions::MutateApply<GaugeUpdateTimeDerivatives>,
              ::Actions::MutateApply<
                  GaugeAdjustedBoundaryValue<Tags::DuRDividedByR>>,
              ::Actions::MutateApply<PrecomputeCceDependencies<
                  Tags::EvolutionGaugeBoundaryValue, Tags::DuRDividedByR>>>,
          tmpl::list<>>>;

  using compute_scri_quantities_and_observe = tmpl::list<
      ::Actions::MutateApply<
          CalculateScriPlusValue<::Tags::dt<Tags::InertialRetardedTime>>>,
      Actions::CalculateScriInputs,
      tmpl::transform<typename metavariables::cce_scri_tags,
                      tmpl::bind<::Actions::MutateApply,
                                 tmpl::bind<CalculateScriPlusValue, tmpl::_1>>>,
      tmpl::transform<
          typename metavariables::scri_values_to_observe,
          tmpl::bind<Actions::InsertInterpolationScriData, tmpl::_1>>,
      Actions::ScriObserveInterpolated<
          observers::ObserverWriter<Metavariables>>>;

  using record_time_stepper_data_and_step =
      tmpl::list<::Actions::RecordTimeStepperData<
                     typename Metavariables::evolved_coordinates_variables_tag>,
                 ::Actions::RecordTimeStepperData<::Tags::Variables<
                     tmpl::list<typename Metavariables::evolved_swsh_tag>>>,
                 ::Actions::UpdateU<
                     typename Metavariables::evolved_coordinates_variables_tag>,
                 ::Actions::UpdateU<::Tags::Variables<
                     tmpl::list<typename Metavariables::evolved_swsh_tag>>>,
                 ::Actions::AdvanceTime>;

  using extract_action_list = tmpl::list<
      Actions::RequestNextBoundaryData<
          typename Metavariables::cce_boundary_component,
          CharacteristicEvolution<Metavariables>>,
      Actions::UpdateGauge, Actions::PrecomputeGlobalCceDependencies,
      tmpl::transform<bondi_hypersurface_step_tags,
                      tmpl::bind<hypersurface_computation, tmpl::_1>>,
      Actions::FilterSwshVolumeQuantity<Tags::BondiH>,
      compute_scri_quantities_and_observe, record_time_stepper_data_and_step,
      Actions::ExitIfEndTimeReached,
      Actions::ReceiveWorldtubeData<Metavariables>>;

  using phase_dependent_action_list =
      tmpl::list<Parallel::PhaseActions<typename Metavariables::Phase,
                                        Metavariables::Phase::Initialization,
                                        initialize_action_list>,
                 Parallel::PhaseActions<typename Metavariables::Phase,
                                        Metavariables::Phase::Evolve,
                                        extract_action_list>>;

  using const_global_cache_tag_list =
      Parallel::get_const_global_cache_tags_from_actions<
          phase_dependent_action_list>;

  static void initialize(Parallel::CProxy_ConstGlobalCache<
                         Metavariables>& /*global_cache*/) noexcept {}

  static void execute_next_phase(
      const typename Metavariables::Phase next_phase,
      const Parallel::CProxy_ConstGlobalCache<Metavariables>&
          global_cache) noexcept {
    auto& local_cache = *(global_cache.ckLocalBranch());
    Parallel::get_parallel_component<CharacteristicEvolution<Metavariables>>(
        local_cache)
        .start_phase(next_phase);
  }
};
}  // namespace Cce