BranchAndBoundCallback.h

//
// Created by henri on 12/04/23.
//
 
#ifndef IDOL_BRANCHANDBOUNDCALLBACK_H
#define IDOL_BRANCHANDBOUNDCALLBACK_H
 
#include "idol/mixed-integer/optimizers/callbacks/Callback.h"
#include "idol/mixed-integer/optimizers/branch-and-bound/nodes/Node.h"
#include "idol/mixed-integer/optimizers/branch-and-bound/Optimizers_BranchAndBound.h"
#include "AbstractBranchAndBoundCallbackI.h"
#include "CallbackAsBranchAndBoundCallback.h"
 
namespace idol {
 
    template<class NodeInfoT>
    class BranchAndBoundCallback;
 
    template<class NodeInfoT>
    class BranchAndBoundCallbackI;
 
}
template<class NodeInfoT>
class idol::BranchAndBoundCallbackI : public AbstractBranchAndBoundCallbackI<NodeInfoT> {
    friend class BranchAndBoundCallback<NodeInfoT>;
 
    std::list<std::unique_ptr<BranchAndBoundCallback<NodeInfoT>>> m_callbacks;
 
    Optimizers::BranchAndBound<NodeInfoT>* m_parent = nullptr;
    std::optional<Node<NodeInfoT>> m_node;
    Model* m_relaxation = nullptr;
    SideEffectRegistry* m_registry = nullptr;
 
public:
    virtual ~BranchAndBoundCallbackI() = default;
protected:
    void add_user_cut(const TempCtr &t_cut);
 
    void add_lazy_cut(const TempCtr &t_cut);
 
    void add_local_variable_branching(const idol::Var &t_var, CtrType t_type, double t_rhs);
 
    [[nodiscard]] const Node<NodeInfoT>& node() const;
 
    [[nodiscard]] const Model& relaxation() const;
 
    [[nodiscard]] const Model& original_model() const;
 
    [[nodiscard]] const Timer& time() const;
 
    [[nodiscard]] const SideEffectRegistry& side_effect_registry() const;
 
    void submit_heuristic_solution(NodeInfoT* t_info);
 
    void submit_bound(double t_bound);
 
    [[nodiscard]] double best_bound() const;
 
    [[nodiscard]] double best_obj() const;
 
    void terminate();
 
    SideEffectRegistry operator()(
            Optimizers::BranchAndBound<NodeInfoT> *t_parent,
            CallbackEvent t_event,
            const Node<NodeInfoT>& t_current_node,
            Model *t_relaxation) override;
 
    void add_callback(BranchAndBoundCallback<NodeInfoT> *t_cb) override;
 
    void initialize(Optimizers::BranchAndBound<NodeInfoT>* t_parent) override;
 
    void log_after_termination() override;
};
 
template<class NodeInfoT>
void idol::BranchAndBoundCallbackI<NodeInfoT>::add_local_variable_branching(const idol::Var &t_var, CtrType t_type, double t_rhs) {
    m_node->info().add_branching_variable(t_var, t_type, t_rhs);
    m_registry->n_added_local_variable_branching++;
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallbackI<NodeInfoT>::terminate() {
    m_parent->terminate();
}
 
template<class NodeInfoT>
double idol::BranchAndBoundCallbackI<NodeInfoT>::best_obj() const {
    return m_parent->get_best_obj();
}
 
template<class NodeInfoT>
double idol::BranchAndBoundCallbackI<NodeInfoT>::best_bound() const {
    return m_parent->get_best_bound();
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallbackI<NodeInfoT>::log_after_termination() {
 
    if (m_callbacks.empty()) {
        return;
    }
 
    std::cout << "Callbacks:" << std::endl;
 
    for (auto& ptr_to_cb : m_callbacks) {
        ptr_to_cb->log_after_termination();
    }
 
    std::cout << std::endl;
 
}
 
template<class NodeInfoT>
const idol::SideEffectRegistry &idol::BranchAndBoundCallbackI<NodeInfoT>::side_effect_registry() const {
    if (!m_registry) {
        throw Exception("No side effect registry was found");
    }
    return *m_registry;
}
 
template<class NodeInfoT>
const idol::Timer &idol::BranchAndBoundCallbackI<NodeInfoT>::time() const {
    return m_parent->time();
}
 
template<class NodeInfoT>
class idol::BranchAndBoundCallback {
public:
    virtual ~BranchAndBoundCallback() = default;
protected:
 
    virtual void initialize() {}
 
    virtual void operator()(CallbackEvent t_event) = 0;
 
    virtual void log_after_termination() {}
 
    void add_user_cut(const TempCtr& t_cut);
 
    void add_lazy_cut(const TempCtr& t_cut);
 
    void add_local_variable_branching(const Var &t_var, CtrType t_type, double t_rhs);
 
    [[nodiscard]] const Node<NodeInfoT>& node() const;
 
    [[nodiscard]] const Model& relaxation() const;
 
    [[nodiscard]] const Model& original_model() const;
 
    void submit_heuristic_solution(NodeInfoT* t_info);
 
    void submit_bound(double t_bound);
 
     const SideEffectRegistry& side_effect_registry() const;
 
    [[nodiscard]] const Timer& time() const;
 
    double best_bound() const;
 
    double best_obj() const;
 
    void terminate();
private:
    BranchAndBoundCallbackI<NodeInfoT>* m_interface = nullptr;
 
    void throw_if_no_interface() const;
 
    friend class BranchAndBoundCallbackI<NodeInfoT>;
};
 
template<class NodeInfoT>
void idol::BranchAndBoundCallback<NodeInfoT>::add_local_variable_branching(const Var &t_var, CtrType t_type, double t_rhs) {
    throw_if_no_interface();
    m_interface->add_local_variable_branching(t_var, t_type, t_rhs);
}
 
template<class NodeInfoT>
double idol::BranchAndBoundCallback<NodeInfoT>::best_obj() const {
    throw_if_no_interface();
    return m_interface->best_obj();
}
 
template<class NodeInfoT>
double idol::BranchAndBoundCallback<NodeInfoT>::best_bound() const {
    throw_if_no_interface();
    return m_interface->best_bound();
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallback<NodeInfoT>::terminate() {
    throw_if_no_interface();
    m_interface->terminate();
}
 
template<class NodeInfoT>
const idol::SideEffectRegistry &idol::BranchAndBoundCallback<NodeInfoT>::side_effect_registry() const {
    throw_if_no_interface();
    return m_interface->side_effect_registry();
}
 
template<class NodeInfoT>
const idol::Timer &idol::BranchAndBoundCallback<NodeInfoT>::time() const {
    throw_if_no_interface();
    return m_interface->time();
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallback<NodeInfoT>::submit_bound(double t_bound) {
    throw_if_no_interface();
    m_interface->submit_bound(t_bound);
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallback<NodeInfoT>::submit_heuristic_solution(NodeInfoT *t_info) {
    throw_if_no_interface();
    m_interface->submit_heuristic_solution(t_info);
}
 
template<class NodeInfoT>
const idol::Model &idol::BranchAndBoundCallback<NodeInfoT>::original_model() const {
    throw_if_no_interface();
    return m_interface->original_model();
}
 
template<class NodeInfoT>
const idol::Model &idol::BranchAndBoundCallback<NodeInfoT>::relaxation() const {
    throw_if_no_interface();
    return m_interface->relaxation();
}
 
template<class NodeInfoT>
const idol::Node<NodeInfoT> &idol::BranchAndBoundCallback<NodeInfoT>::node() const {
    throw_if_no_interface();
    return m_interface->node();
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallback<NodeInfoT>::add_lazy_cut(const TempCtr &t_cut) {
    throw_if_no_interface();
    m_interface->add_lazy_cut(t_cut);
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallback<NodeInfoT>::add_user_cut(const TempCtr &t_cut) {
    throw_if_no_interface();
    m_interface->add_user_cut(t_cut);
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallback<NodeInfoT>::throw_if_no_interface() const {
    if (!m_interface) {
        throw Exception("No interface was found.");
    }
}
 
template<class NodeInfoT>
idol::SideEffectRegistry
idol::BranchAndBoundCallbackI<NodeInfoT>::operator()(Optimizers::BranchAndBound<NodeInfoT> *t_parent,
                                                     CallbackEvent t_event,
                                                     const Node<NodeInfoT> &t_current_node,
                                                     Model *t_relaxation) {
    SideEffectRegistry result;
 
    m_parent = t_parent;
    m_node = t_current_node;
    m_relaxation = t_relaxation;
    m_registry = &result;
 
    for (auto &cb: m_callbacks) {
        cb->m_interface = this;
        cb->operator()(t_event);
        cb->m_interface = nullptr;
    }
 
    m_parent = nullptr;
    m_node.reset();
    m_relaxation = nullptr;
    m_registry = nullptr;
 
    return result;
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallbackI<NodeInfoT>::add_callback(BranchAndBoundCallback<NodeInfoT> *t_cb) {
    m_callbacks.emplace_back(t_cb);
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallbackI<NodeInfoT>::initialize(Optimizers::BranchAndBound<NodeInfoT>* t_parent) {
 
    m_parent = t_parent;
 
    for (auto& ptr_callback : m_callbacks) {
        ptr_callback->m_interface = this;
        ptr_callback->initialize();
        ptr_callback->m_interface = nullptr;
    }
 
    m_parent = nullptr;
 
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallbackI<NodeInfoT>::submit_bound(double t_bound) {
    if (!m_parent) {
        throw Exception("submit_bound is not accessible in this context.");
    }
    m_parent->submit_lower_bound(t_bound);
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallbackI<NodeInfoT>::submit_heuristic_solution(NodeInfoT *t_info) {
    if (!m_parent) {
        throw Exception("submit_heuristic_solution is not accessible in this context.");
    }
    m_parent->submit_heuristic_solution(t_info);
}
 
template<class NodeInfoT>
const idol::Model &idol::BranchAndBoundCallbackI<NodeInfoT>::original_model() const {
    if (!m_parent) {
        throw Exception("original_model is not accessible in this context.");
    }
    return m_parent->parent();
}
 
template<class NodeInfoT>
const idol::Model &idol::BranchAndBoundCallbackI<NodeInfoT>::relaxation() const {
    if (!m_relaxation) {
        throw Exception("relaxation is not accessible in this context.");
    }
    return *m_relaxation;
}
 
template<class NodeInfoT>
const idol::Node<NodeInfoT> &idol::BranchAndBoundCallbackI<NodeInfoT>::node() const {
    if (!m_node) {
        throw Exception("node is not accessible in this context.");
    }
    return *m_node;
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallbackI<NodeInfoT>::add_lazy_cut(const TempCtr &t_cut) {
    m_relaxation->add_ctr(t_cut);
    ++m_registry->n_added_lazy_cuts;
}
 
template<class NodeInfoT>
void idol::BranchAndBoundCallbackI<NodeInfoT>::add_user_cut(const TempCtr &t_cut) {
    m_relaxation->add_ctr(t_cut);
    ++m_registry->n_added_user_cuts;
}
 
#endif //IDOL_BRANCHANDBOUNDCALLBACK_H