Strips the time from a date with respect to the user's timezone

NSDate+Additions.m

//
//  NSDate+Additions.m
//
//  Created by Trevor Sheridan on 10/1/12.
//  Copyright (c) 2012 Trevor Sheridan Inc. All rights reserved.
//

#import "NSDate+Additions.h"

@implementation NSDate (Additions)

- (NSDate *)dateWithoutTime
{
    return [[self class] dateWithoutTime:self];
}

- (NSDate *)dateInCurrentTimezone
{
    return [[self class] dateInCurrentTimeZone:self];
}

// Return the date without time in the user's current time zone.
+ (NSDate *)dateWithoutTime:(NSDate *)date
{
    date = [self dateInCurrentTimeZone:date];
    
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDateComponents *components = [calendar components:NSTimeZoneCalendarUnit | NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSSecondCalendarUnit fromDate:date];
    
    /* If date's time is set to 06:00:00 in the Mountain Time Zone, simply set the seconds to the
     offset. So -21600 seconds + 06:00:00 = 00:00:00. This should work for all timezones.
     */
    components.second = [components.timeZone secondsFromGMT];
    
    return [calendar dateFromComponents:components];
}

// Given a UTC date (GMT offset 0) return a new date to midnight in the user's current timezone.
+ (NSDate *)dateInCurrentTimeZone:(NSDate *)date
{
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDateComponents *components = [calendar components:NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit fromDate:date];
    
    return [calendar dateFromComponents:components];
}

@end