// Copyright 2016 Google Inc. All Rights Reserved.

//

// Licensed under the Apache License, Version 2.0 (the "License");

// you may not use this file except in compliance with the License.

// You may obtain a copy of the License at

//

//   https://www.apache.org/licenses/LICENSE-2.0

//

//   Unless required by applicable law or agreed to in writing, software

//   distributed under the License is distributed on an "AS IS" BASIS,

//   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

//   See the License for the specific language governing permissions and

//   limitations under the License.

#ifndef CCTZ_TIME_ZONE_IMPL_H_

#define CCTZ_TIME_ZONE_IMPL_H_

#include <memory>

#include <string>

#include "cctz/civil_time.h"

#include "cctz/time_zone.h"

#include "time_zone_if.h"

#include "time_zone_info.h"

namespace cctz {

// time_zone::Impl is the internal object referenced by a cctz::time_zone.

class time_zone::Impl {

 public:

  // The UTC time zone. Also used for other time zones that fail to load.

  static time_zone UTC();

  // Load a named time zone. Returns false if the name is invalid, or if

  // some other kind of error occurs. Note that loading "UTC" never fails.

  static bool LoadTimeZone(const std::string& name, time_zone* tz);

  // Clears the map of cached time zones.  Primarily for use in benchmarks

  // that gauge the performance of loading/parsing the time-zone data.

  static void ClearTimeZoneMapTestOnly();

  // The primary key is the time-zone ID (e.g., "America/New_York").

  const std::string& Name() const {

    // TODO: It would nice if the zoneinfo data included the zone name.

    return name_;

  }

  // Breaks a time_point down to civil-time components in this time zone.

  time_zone::absolute_lookup BreakTime(const time_point<seconds>& tp) const {

    return zone_->BreakTime(tp);

  }

  // Converts the civil-time components in this time zone into a time_point.

  // That is, the opposite of BreakTime(). The requested civil time may be

  // ambiguous or illegal due to a change of UTC offset.

  time_zone::civil_lookup MakeTime(const civil_second& cs) const {

    return zone_->MakeTime(cs);

  }

  // Finds the time of the next/previous offset change in this time zone.

  bool NextTransition(const time_point<seconds>& tp,

                      time_zone::civil_transition* trans) const {

    return zone_->NextTransition(tp, trans);

  }

  bool PrevTransition(const time_point<seconds>& tp,

                      time_zone::civil_transition* trans) const {

    return zone_->PrevTransition(tp, trans);

  }

  // Returns an implementation-defined version string for this time zone.

  std::string Version() const { return zone_->Version(); }

  // Returns an implementation-defined description of this time zone.

  std::string Description() const { return zone_->Description(); }

 private:

  Impl();

  explicit Impl(const std::string& name);

  Impl(const Impl&) = delete;

  Impl& operator=(const Impl&) = delete;

  static const Impl* UTCImpl();

  const std::string name_;

  std::unique_ptr<TimeZoneIf> zone_;

};

}  // namespace cctz

#endif  // CCTZ_TIME_ZONE_IMPL_H_