#ifndef FESA_CONSTRAINTS_PRESCRIBED_DISPLACEMENT_H_
#define FESA_CONSTRAINTS_PRESCRIBED_DISPLACEMENT_H_

#include <cstddef>

#include "fesa/constraints/boundary_condition.h"
#include "fesa/core/diagnostic.h"
#include "fesa/elements/element.h"
#include "fesa/model/source_target_resolver.h"

namespace fesa {

/// @brief Emits one prescribed nodal displacement component for a target.
class PrescribedDisplacementBoundaryCondition final : public BoundaryCondition {
 public:
  /// @brief Creates one prescribed component in stable source order.
  PrescribedDisplacementBoundaryCondition(SourceTargetQuery target,
                                          DofComponent component,
                                          double prescribed_value,
                                          std::size_t source_order,
                                          SourceLocation location = {});

  /// @brief Resolves target-major full-DOF constraint definitions.
  Result<std::vector<ConstraintDefinition>> ResolveConstraints(
      const BoundaryConditionContext& context) const override;

  /// @brief Returns the immutable source target query.
  const SourceTargetQuery& Target() const noexcept;

  /// @brief Returns the prescribed global DOF component.
  DofComponent Component() const noexcept;

  /// @brief Returns the exact prescribed displacement value.
  double PrescribedValue() const noexcept;

  /// @brief Returns the stable boundary-definition order.
  std::size_t SourceOrder() const noexcept;

 private:
  SourceTargetQuery target_;
  DofComponent component_;
  double prescribed_value_;
  std::size_t source_order_;
};

}  // namespace fesa

#endif  // FESA_CONSTRAINTS_PRESCRIBED_DISPLACEMENT_H_