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#ifndef ROSBAG_TIME_TRANSLATOR_H
#define ROSBAG_TIME_TRANSLATOR_H

#include "ros/time.h"

namespace rosbag {

//! Helper class for translating between two times
/*!
 * The time translator can be configured with a Real start time, a
 * Translated start time, and a time scale.
 * 
 * It will convert a time from a series starting at realStartTime to a
 * comparable time series instead starting at translatedStartTime.
 * All durations in the time-sequence as scaled by 1/(timeScale).
 *
 * That is, a time-sequence with time-scale 2 will finish twice as
 * quickly.
 */
class TimeTranslator
{
public:
    TimeTranslator();

    void      setTimeScale(double const& s);
    void      setRealStartTime(ros::Time const& t);
    void      setTranslatedStartTime(ros::Time const& t);  //!< Increments the translated start time by shift.  Useful for pausing.
    void      shift(ros::Duration const& d);               //!< Increments the translated start time by shift.  Useful for pausing.
    ros::Time translate(ros::Time const& t);

private:
    double    time_scale_;
    ros::Time real_start_;
    ros::Time translated_start_;
};

} // namespace rosbag

#endif
