DateTime.swift

//
//  main.swift
//  DateTime
//
//  Created by woowabrothers on 2017. 7. 11..
//  Copyright © 2017년 woowabrothers. All rights reserved.
//

import Foundation

typealias CurrentTime = (year: Int, month: Int, day: Int, hour: Int, minute: Int, second: Int)

class MyCalendar{
    
    let date = Date()
    var calendar =  Calendar.current
    
    // 현재 시간 가져오기
    func getTime() -> CurrentTime {
        let year = calendar.component(.year, from: date)
        let month = calendar.component(.month, from: date)
        let day = calendar.component(.day, from: date)
        let hour = calendar.component(.hour, from: date)
        let minutes = calendar.component(.minute, from: date)
        let seconds = calendar.component(.second, from: date)
        
        let result: CurrentTime = (year, month, day, hour, minutes, seconds)
        
        return result
    }
    
    
    
    // Int 형식을 Date로 리턴
    func makeDateByInt(year: Int, month: Int, day: Int) -> Date {
 
        var localCalendar =  Calendar.current
        
        var component = DateComponents()
        component.year = year
        component.month = month
        component.day = day
        
        localCalendar.timeZone = TimeZone(abbreviation: "GMT+0.00")!
        
        let resultDate = localCalendar.date(from: component)
        
        return resultDate!
    }
    
    // String 형식을 Date로 리턴
    func makeDateByString(year: String, month: String, day: String) -> Date {

        // 날짜 설정
        var component = DateComponents()
        component.year = Int(year)
        component.month = Int(month)
        component.day = Int(day)
        
        // timeZone 설정
        var localCalendar = Calendar(identifier: .gregorian)
        localCalendar.timeZone = TimeZone(abbreviation: "GMT+0.00")!
        
        
        let resultDate = localCalendar.date(from: component)
        return resultDate!
    }
    
    // 한국식 날짜 리턴
    func dateToKoreanDate(inputDate: Date) -> String {
        
        let dateFormatter =  DateFormatter()
        dateFormatter.dateFormat = "yyyy년 MM월 dd일"
        
        let resultString = dateFormatter.string(from: inputDate)
     
        return resultString
    }
    
    // 날짜를 통해서 1일의 요일 구하기
    func getDateOfMonth(year: String, month: String) -> String {
        
        let formatter  = DateFormatter()
        formatter.dateFormat = "yyyy-MM-dd"
        
        guard let targetDate = formatter.date(from: year + "-" + month + "-" + "01") else { return "" }
        
        var calendar = Calendar(identifier: .gregorian)
        calendar.timeZone = TimeZone(secondsFromGMT: -9 * 60 * 60)!
        let weekDay = calendar.component(.weekday, from: targetDate)

        switch weekDay {
        case 1:
            return "월요일"
        case 2:
            return "화요일"
        case 3:
            return "수요일"
        case 4:
            return "목요일"
        case 5:
            return "금요일"
        case 6:
            return "토요일"
        case 7:
            return "일요일"
        default:
            fatalError()
        }
    }
   
    func makeCalendarArray(year: String, month: String) -> [[Int]] {
        var calendar = Calendar(identifier: .gregorian)
        calendar.timeZone = TimeZone(abbreviation: "GMT+0.00")!
        
        let formatter  = DateFormatter()
        formatter.dateFormat = "yyyy-MM"

        guard var interval = calendar.dateInterval(of: .month, for: Date()) else { return  [] }
        
        interval.end.addTimeInterval(-1)
        
        var resultArr: [[Int]] = []

        let lastDay = calendar.component(.day, from: interval.end) // 31
        var weekDay = calendar.component(.weekday, from: interval.start)

        var day = 1
        while day <= lastDay {
            var weekArr: [Int] = []
            while day <= lastDay {
                if weekDay <= 7 {
                    weekArr.append(day)
                    day += 1
                    weekDay += 1
                } else {
                    weekDay = 1
                    resultArr.append(weekArr)
                    break
                }
            }
            if day >= lastDay {
                resultArr.append(weekArr)
            }
        }
        
        return resultArr
    }
}


let calendar = MyCalendar()

print(calendar.getTime())
print(calendar.makeDateByInt(year: 1998, month: 12, day: 25))
print(calendar.makeDateByString(year: "2016", month: "4", day: "16"))

print(calendar.dateToKoreanDate(inputDate: calendar.makeDateByString(year: "1998", month: "12", day: "25")))

print(calendar.getDateOfMonth(year: "2010", month: "01"))
print(calendar.makeCalendarArray(year: "2010", month: "04"))