//

// SKSensorTimestamp.h

// SensingKit

//

// Copyright (c) 2014. Queen Mary University of London

// Kleomenis Katevas, k.katevas@qmul.ac.uk

//

// This file is part of SensingKit-iOS library.

// For more information, please visit http://www.sensingkit.org

//

// SensingKit-iOS is free software: you can redistribute it and/or modify

// it under the terms of the GNU Lesser General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// SensingKit-iOS is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

// GNU Lesser General Public License for more details.

//

// You should have received a copy of the GNU Lesser General Public License

// along with SensingKit-iOS. If not, see <http://www.gnu.org/licenses/>.

//

#import <Foundation/Foundation.h>

NS_ASSUME_NONNULL_BEGIN

/**

* SKSensorTimestamp object represent a single point in time.

*/

@interface SKSensorTimestamp : NSObject <NSCopying>

- (instancetype)init NS_UNAVAILABLE;

/**

* Creates and returns a new SKSensorTimestamp from an NSDate object. If the sensor does not provide an NSDate object, [NSDate date] can be used.

*

* @param date The absolute date that this SKSensorTimestamp object should be initialized with.

*

* @return A new SKSensorTimestamp object initialized with the (NSDate *)date parameter.

*/

+ (instancetype)sensorTimestampFromDate:(NSDate *)date;

/**

* Creates and returns a new SKSensorTimestamp from a NSTimeInterval object. The time interval should be relative to the last time the device was boot. If the sensor does not provide this value, [NSProcessInfo processInfo].systemUptime can be used.

*

* @param timeInterval The number of seconds since the last time the device was boot.

*

* @return A new SKSensorTimestamp object initialized relative to the timeInterval parameter.

*/

+ (instancetype)sensorTimestampFromTimeInterval:(NSTimeInterval)timeInterval;

/**

* Returns an NSDate object of the sensor timestamp.

*/

@property (nonatomic, readonly, copy) NSDate *timestamp;

/**

* Returns the interval between the timestamp and the last time the device was boot.

*/

@property (nonatomic, readonly) NSTimeInterval timeIntervalSinceLastBoot;

/**

* Returns a dictionary that encapsulates the timestamp as a string, the interval since 1970, and the interval since the device was boot.

*/

@property (nonatomic, readonly, copy) NSDictionary *timestampDictionary;

/**

* Returns a string representation of the timestamp. The format of the string is "yyyy-MM-dd HH:mm:ss.SSS ZZZ".

*/

@property (nonatomic, readonly, copy) NSString *timestampString;

/**

* Returns the interval between the timestamp and 00:00:00 UTC on 1 January 1970.

*/

@property (nonatomic, readonly) NSTimeInterval timeIntervalSince1970;

@end

NS_ASSUME_NONNULL_END