//
//  RCTAppleHealthKit+Utils.m
//  RCTAppleHealthKit
//
//  Created by Greg Wilson on 2016-06-26.
//  Copyright © 2016 Greg Wilson. All rights reserved.
//

#import "RCTAppleHealthKit+Utils.h"

@implementation RCTAppleHealthKit (Utils)

#pragma mark - Utilities

+ (NSDate *)parseISO8601DateFromString:(NSString *)date
{
    NSDateFormatter *dateFormatter = [NSDateFormatter new];
    NSLocale *posix = [NSLocale localeWithLocaleIdentifier:@"en_US_POSIX"];
    dateFormatter.locale = posix;
    dateFormatter.dateFormat = @"yyyy-MM-dd'T'HH:mm:ssZZZZZ";
    return [dateFormatter dateFromString:date];
}

+ (NSString *)buildISO8601StringFromDate:(NSDate *)date
{
    NSDateFormatter *dateFormatter = [NSDateFormatter new];
    NSLocale *posix = [NSLocale localeWithLocaleIdentifier:@"en_US_POSIX"];
    dateFormatter.locale = posix;
    dateFormatter.dateFormat = @"yyyy-MM-dd'T'HH:mm:ssZZZZZ";
    return [dateFormatter stringFromDate:date];
}

+ (NSPredicate *)predicateForSamplesToday {
    NSDate *now = [NSDate date];
    return [RCTAppleHealthKit predicateForSamplesOnDay:now];
}

+ (NSPredicate *)predicateForSamplesOnDayFromTimestamp:(NSString *)timestamp {
    NSDate *day = [RCTAppleHealthKit parseISO8601DateFromString:timestamp];
    return [RCTAppleHealthKit predicateForSamplesOnDay:day];
}

+ (NSPredicate *)predicateForSamplesOnDay:(NSDate *)date {
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDate *startDate = [calendar startOfDayForDate:date];
    NSDate *endDate = [calendar dateByAddingUnit:NSCalendarUnitDay value:1 toDate:startDate options:0];
    return [HKQuery predicateForSamplesWithStartDate:startDate endDate:endDate options:HKQueryOptionStrictStartDate];
}

@end