mass_balance.hpp

/*
Author: Nels Frazier
Copyright (C) 2025 Lynker
------------------------------------------------------------------------
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.
------------------------------------------------------------------------
Version 0.3
Implement is_supported()
Re-align members for more better memory layout/padding
Update docstrings
 
Version 0.2
Conform to updated protocol interface
Removed integration and error exceptions in favor of ProtocolError
 
Version 0.1
Interface of the BMI mass balance protocol
*/
#pragma once
 
#include <nonstd/expected.hpp>
#include <protocol.hpp>
 
namespace models {
namespace bmi {
namespace protocols {
using nonstd::expected;
constexpr const char* const INPUT_MASS_NAME  = "ngen::mass_in";
constexpr const char* const OUTPUT_MASS_NAME = "ngen::mass_out";
constexpr const char* const STORED_MASS_NAME = "ngen::mass_stored";
constexpr const char* const LEAKED_MASS_NAME = "ngen::mass_leaked";
 
// The top level object key which will contain the map of configuration options
constexpr const char* const CONFIGURATION_KEY = "mass_balance";
// Configuration option keys
constexpr const char* const TOLERANCE_KEY = "tolerance";
constexpr const char* const FATAL_KEY     = "fatal";
constexpr const char* const CHECK_KEY     = "check";
constexpr const char* const FREQUENCY_KEY = "frequency";
 
class NgenMassBalance : public NgenBmiProtocol {
  public:
    NgenMassBalance(const ModelPtr& model, const Properties& properties);
 
    NgenMassBalance();
 
    virtual ~NgenMassBalance() override;
 
  private:
    auto run(const ModelPtr& model, const Context& ctx) const
        -> expected<void, ProtocolError> override;
 
    nsel_NODISCARD auto check_support(const ModelPtr& model)
        -> expected<void, ProtocolError> override;
 
    auto initialize(const ModelPtr& model, const Properties& properties)
        -> expected<void, ProtocolError> override;
 
    bool is_supported() const override final;
 
  private:
    double tolerance;
    // How often (in time steps) to check mass balance
    int frequency;
    // Whether the protocol is supported by the model, false by default
    bool supported = false;
    // Configurable options/values
    bool check;
    bool is_fatal;
};
 
} // namespace protocols
} // namespace bmi
} // namespace models