#ifndef FESA_ASSEMBLY_PARALLEL_FOR_H_
#define FESA_ASSEMBLY_PARALLEL_FOR_H_

#include <cstddef>
#include <functional>

namespace fesa {

/// @brief Executes independent index-addressed work behind a backend boundary.
/// @note Callers own output storage and each invocation may write only its
/// index-owned slot.
class ParallelFor {
 public:
  virtual ~ParallelFor() = default;

  /// @brief Invokes body once for every index in [0, count).
  virtual void Execute(std::size_t count,
                       const std::function<void(std::size_t)>& body) const = 0;
};

/// @brief Executes index-addressed work serially.
class SerialParallelFor final : public ParallelFor {
 public:
  /// @copydoc ParallelFor::Execute
  void Execute(std::size_t count,
               const std::function<void(std::size_t)>& body) const override;
};

/// @brief Executes index-addressed work through oneTBB.
class TbbParallelFor final : public ParallelFor {
 public:
  /// @copydoc ParallelFor::Execute
  void Execute(std::size_t count,
               const std::function<void(std::size_t)>& body) const override;
};

}  // namespace fesa

#endif  // FESA_ASSEMBLY_PARALLEL_FOR_H_