Custom date picker with "infinite" hours and minutes

picker.swift

import UIKit

@objc protocol CustomDatePickerSourceDelegate:NSObjectProtocol {
  func datePickerDidSelectDate(date:NSDate)
}

@objc class CustomDatePickerSource: NSObject {
  
  enum Component:Int {
    case Day = 0
    case Hour = 1
    case Minute = 2
  }
  
  private let currentDate   = NSDate()
  private let dateFormatter = NSDateFormatter()
  private let numberFormatter = NSNumberFormatter()
  
  private var days:[NSDate] = []
  private var hours:[Int] = []
  private var minutes:[Int] = []
  
  @IBOutlet weak var delegate:CustomDatePickerSourceDelegate?
  
  private var selectedDate:(day:NSDate, hour:Int, minute:Int)
  
  override init() {
    selectedDate.day = currentDate
    selectedDate.hour = 0
    selectedDate.minute = 0
    
    super.init()
    
    dateFormatter.dateStyle = .MediumStyle
    dateFormatter.timeStyle = .NoStyle
    
    numberFormatter.formatWidth = 2
    numberFormatter.paddingPosition = .BeforePrefix
    numberFormatter.paddingCharacter = "0"
    
    let currentDateComponents = NSCalendar.currentCalendar().components([NSCalendarUnit.Hour, NSCalendarUnit.Minute], fromDate: currentDate)
    
    days    = setupDate(currentDate)
    hours   = setupHours(currentDateComponents.hour)
    minutes = setupMinutes(currentDateComponents.minute, interval: 5)
    
    selectedDate.day    = days[0]
    selectedDate.hour   = hours[0]
    selectedDate.minute = minutes[0]
  }
  
  private func setupDate(startingDate:NSDate) -> [NSDate] {
    var result:[NSDate] = []
    
    let calendar = NSCalendar.currentCalendar()
    let todayComponents = NSDateComponents()
    todayComponents.day   = calendar.component(.Day, fromDate: startingDate)
    todayComponents.month = calendar.component(.Month, fromDate: startingDate)
    todayComponents.year  = calendar.component(.Year, fromDate: startingDate)
    
    let dayComponent = NSDateComponents()
    dayComponent.day = 1
    
    if let today = calendar.dateFromComponents(todayComponents) {
      result.append(today)
      
      var nextDay = today
      for _ in 0...365 {
        if let date = calendar.dateByAddingComponents(dayComponent, toDate: nextDay, options: NSCalendarOptions(rawValue: 0)) {
          result.append(date)
          nextDay = date
        }
      }
    }
    
    return result
  }
  
  private func setupHours(startingHour:Int) -> [Int] {
    var result:[Int] = []
    for i in 0..<24 {
      let value = (startingHour + i) % 24
      result.append(value)
    }
    return result
  }
  
  private func setupMinutes(startingMinute:Int, interval:Int = 1) -> [Int] {
    var result:[Int] = []
    let count = Int(60.0 / Double(interval))
    for i in 0..<count {
      let value = ((Int(ceil(Double(startingMinute) / Double(interval))) + i + 1) * interval) % 60
      result.append(value)
    }
    return result
  }
  
  private func currentSelectedDate() -> NSDate? {
    let timeComponents = NSDateComponents()
    timeComponents.hour = selectedDate.hour
    timeComponents.minute = selectedDate.minute
    
    if let date = NSCalendar.currentCalendar().dateByAddingComponents(timeComponents, toDate: selectedDate.day, options: NSCalendarOptions(rawValue: 0)) {
      return date
    }
    return nil
  }
}

extension CustomDatePickerSource : UIPickerViewDataSource {
  func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
    return 3
  }
  
  func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
    if let column = Component(rawValue: component) {
      switch column {
      case .Day:     return days.count
      case .Hour:    return Int(Int16.max)//hours.count
      case .Minute:  return Int(Int16.max)//minutes.count
      }
    }
    return 10
  }
}

extension CustomDatePickerSource : UIPickerViewDelegate {
  
  func pickerView(pickerView: UIPickerView, widthForComponent component: Int) -> CGFloat {
    if let column = Component(rawValue: component) {
      switch column {
      case .Day:     return 150.0
      case .Hour:    return 40.0
      case .Minute:  return 40.0
      }
    }
    return 100.0
  }
  
  func pickerView(pickerView: UIPickerView, rowHeightForComponent component: Int) -> CGFloat {
    return 50.0
  }
  
  func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    if let column = Component(rawValue: component) {
      switch column {
        
      case .Day:
        return dateFormatter.stringFromDate(days[row])
        
      case .Hour:
        return "\(numberFormatter.stringFromNumber(hours[row % hours.count])!)"
        
      case .Minute:
        return "\(numberFormatter.stringFromNumber(minutes[row % minutes.count])!)"
      }
    }
    return ""
  }
  
  func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    if let column = Component(rawValue: component) {
      switch column {
      case .Day:     selectedDate.day     = days[row]
      case .Hour:    selectedDate.hour    = hours[row % hours.count]
      case .Minute:  selectedDate.minute  = minutes[row % minutes.count]
      }
    }
    
    if let date = currentSelectedDate() {
      delegate?.datePickerDidSelectDate(date)
    }
  }
}