aocpp/lib/include/intcode/Machine.hpp

#ifndef INTCODE_MACHINE_HPP_
#define INTCODE_MACHINE_HPP_

#include <cstddef>
#include <unordered_map>
#include <vector>

namespace intcode {

using ValueType = std::int64_t;

class Machine {
  std::vector<ValueType> rom_;
  std::unordered_map<std::size_t, ValueType> ram_;
  std::size_t pc_;
  std::size_t base_;

public:
  Machine();
  explicit Machine(std::vector<ValueType> ram);

  /// Access memory at absolute address
  /// @param address
  /// @return reference to memory at given address
  auto At(std::size_t address) -> ValueType &;

  /// Access memory at address relative to base pointer
  /// @param offset from base pointer
  /// @return reference to memory at given offset
  auto Rel(std::size_t offset) -> ValueType &;

  auto Next() -> ValueType &;
  auto Goto(std::size_t address) -> void;
  auto Rebase(std::size_t offset) -> void;
};

} // namespace

#endif