itimestamp.h

#pragma once
#include <string>
 
namespace mdf {
 
namespace timeunits {
constexpr uint64_t kNanosecondsPerSecond = 1'000'000'000;
constexpr uint64_t kNanosecondsPerMinute = 60 * kNanosecondsPerSecond;
constexpr uint64_t kNanosecondsPerHour = 60 * kNanosecondsPerMinute;
constexpr uint32_t kSecondsPerMinute = 60;
constexpr uint32_t kSecondsPerHour = 60 * kSecondsPerMinute;
}  // namespace timeunits
 
class ITimestamp {
 public:
  virtual ~ITimestamp() = default;
  [[nodiscard]] virtual uint64_t GetTimeNs() const = 0;
  [[nodiscard]] virtual int16_t GetTimezoneMin() const = 0;
  [[nodiscard]] virtual int16_t GetDstMin() const = 0;
  [[nodiscard]] virtual uint64_t GetUtcTimeNs() const = 0;
};
 
class UtcTimestamp : public ITimestamp {
 public:
  explicit UtcTimestamp(uint64_t utc_timestamp);
 
  [[nodiscard]] uint64_t GetTimeNs() const override;
  [[nodiscard]] int16_t GetTimezoneMin() const override;
  [[nodiscard]] int16_t GetDstMin() const override;
  [[nodiscard]] uint64_t GetUtcTimeNs() const override;
 
 private:
  uint64_t utc_timestamp_;  
};
 
class LocalTimestamp : public ITimestamp {
 public:
  explicit LocalTimestamp(uint64_t local_timestamp);
  [[nodiscard]] uint64_t GetTimeNs() const override;
  [[nodiscard]] int16_t GetTimezoneMin() const override;
  [[nodiscard]] int16_t GetDstMin() const override;
  [[nodiscard]] uint64_t GetUtcTimeNs() const override;
 
 private:
  uint64_t local_timestamp_;  
  int16_t timezone_offset_min_ = 0;  
  int16_t dst_offset_min_ = 0;  
};
 
class TimezoneTimestamp : public ITimestamp {
 public:
  TimezoneTimestamp(uint64_t utc_timestamp, int16_t timezone_offset_min,
                    int16_t dst_offset_min);
  [[nodiscard]] uint64_t GetTimeNs() const override;
  [[nodiscard]] int16_t GetTimezoneMin() const override;
  [[nodiscard]] int16_t GetDstMin() const override;
  [[nodiscard]] uint64_t GetUtcTimeNs() const override;
 
 private:
  uint64_t utc_timestamp_;       
  int16_t timezone_offset_min_;  
  int16_t dst_offset_min_;  
};
}  // namespace mdf