NSDate.swift

NSDate.swift

//
//  NSDate.swift
//  Smartlink
//
//  Created by Matthieu Riegler on 20/11/15.
//

import Foundation


public func ==(lhs: NSDate, rhs: NSDate) -> Bool {
    return lhs === rhs || lhs.compare(rhs) == .OrderedSame
}

public func <(lhs: NSDate, rhs: NSDate) -> Bool {
    return lhs.compare(rhs) == .OrderedAscending
}

public func >(lhs: NSDate, rhs: NSDate) -> Bool {
    return lhs.compare(rhs) == .OrderedDescending
}

extension NSDate: Comparable { }

/* ISO 8601 Format */
public extension NSDate {
    public func ISOString() -> String {
        let dateFormatter = NSDateFormatter()
        dateFormatter.locale = NSLocale(localeIdentifier: "en_US_POSIX")
        dateFormatter.timeZone = NSTimeZone(abbreviation: "GMT")
        dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSS"
        
        return dateFormatter.stringFromDate(self).stringByAppendingString("Z")
    }
    
    public class func dateFromISOString(string: String) -> NSDate {
        let dateFormatter = NSDateFormatter()
        dateFormatter.locale = NSLocale(localeIdentifier: "en_US_POSIX")
        dateFormatter.timeZone = NSTimeZone.localTimeZone()
        dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZ"
        
        return dateFormatter.dateFromString(string)!
    }
}

public extension NSDate {
    
    public func startOf(unit:NSCalendarUnit) -> NSDate {
        switch unit {
        case NSCalendarUnit.Day:
            return startOfDay()
        case NSCalendarUnit.WeekOfYear:
            return startOfWeek()
        case NSCalendarUnit.Month:
            return startOfMonth()
        case NSCalendarUnit.Year:
            return startOfYear()
        default:
            fatalError("Not implemented yet")
        }
    }
    
    public func endOf(unit:NSCalendarUnit) -> NSDate {
        switch unit {
        case NSCalendarUnit.Day:
            return endOfDay()
        case NSCalendarUnit.WeekOfYear:
            return endOfWeek()
        case NSCalendarUnit.Month:
            return endOfMonth()
        case NSCalendarUnit.Year:
            return endOfYear()
        default:
            fatalError("Not implemented yet")
        }
    }
    
    public func startOfDay() -> NSDate {
        let calendar = NSCalendar.currentCalendar()
        let comps = calendar.components([.Year, .Month, .Day], fromDate: self)
        return calendar.dateFromComponents(comps)!
    }
    
    public func endOfDay() -> NSDate {
        let calendar = NSCalendar.currentCalendar()
        let comps2 = NSDateComponents()
        comps2.day = 1
        comps2.second = -1
        return calendar.dateByAddingComponents(comps2, toDate: startOfDay(), options: [])!
    }
    
    public func startOfWeek() -> NSDate {
        let calendar = NSCalendar.currentCalendar()
        let comps = calendar.components([.Year, .Month, .WeekOfYear, .YearForWeekOfYear], fromDate: self)
        return calendar.dateFromComponents(comps)!
    }
    
    public func endOfWeek() -> NSDate {
        let calendar = NSCalendar.currentCalendar()
        let comps2 = NSDateComponents()
        comps2.weekOfYear = 1
        comps2.second = -1
        return calendar.dateByAddingComponents(comps2, toDate: startOfWeek(), options: [])!
    }
    
    public func startOfMonth() -> NSDate {
        let calendar = NSCalendar.currentCalendar()
        let comps = calendar.components([.Year, .Month], fromDate: self)
        return calendar.dateFromComponents(comps)!
    }
    
    public func endOfMonth() -> NSDate {
        let calendar = NSCalendar.currentCalendar()
        let comps2 = NSDateComponents()
        comps2.month = 1
        comps2.second = -1
        return calendar.dateByAddingComponents(comps2, toDate: startOfMonth(), options: [])!
    }
    
    public func startOfYear() -> NSDate {
        let calendar = NSCalendar.currentCalendar()
        let comps = calendar.components([.Year], fromDate: self)
        return calendar.dateFromComponents(comps)!
    }
    
    public func endOfYear() -> NSDate {
        let calendar = NSCalendar.currentCalendar()
        let comps2 = NSDateComponents()
        comps2.year = 1
        comps2.second = -1
        return calendar.dateByAddingComponents(comps2, toDate: startOfYear(), options: [])!
    }
    
}