add convert method and next and before day

Example/Example/ViewController.swift

@@ -18,7 +18,11 @@ class ViewController: UIViewController {
         super.viewDidLoad()
         persianDatePickerView.onChange = {(year, month, day) in
             print("\(year)/\(month)/\(day)")
+            print(self.persianDatePickerView.getGregorianDate()!)
+            print(self.persianDatePickerView.getPersianDate()!)
+            print("next day : \(self.persianDatePickerView.nextDay(by: self.persianDatePickerView.getPersianDate()!))")
         }
+
     }
     @IBAction func didTapReset(_ sender: Any) {
         persianDatePickerView.gotoCurrentDate()

PersianDatePicker.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = 'PersianDatePicker'
-  s.version          = '0.5.0'
+  s.version          = '0.6.0'
   s.summary          = 'PersianDatePicker is a PickerView. by : farhad faramarzi'
 
 

PersianDatePicker/PersianDateDataSource.swift

@@ -6,7 +6,7 @@
 //  Copyright © 2017 Farhad. All rights reserved.
 //
 
-import Foundation
+import UIKit
 
 struct PersianDateDataSource {
 	//MARK: - Properties
@@ -27,8 +27,10 @@ struct PersianDateDataSource {
 
 
 	func daysRange(ofYear year:Int, month: Int) -> [Int] {
-		let targetDayComponents = DateComponents(calendar: cal, year: year,
-												 month: month, day: 1)
+		let targetDayComponents = DateComponents(calendar: cal,
+                                                 year: year,
+												 month: month,
+                                                 day: 1)
 		guard let targetDay = cal.date(from: targetDayComponents) else { return [] }
 		guard let range = cal.range(of: .day, in: .month, for: targetDay) else { return [] }
 
@@ -39,5 +41,34 @@ struct PersianDateDataSource {
 		let date = Date()
 		let comps = cal.dateComponents([.year, .month, .day], from: date)
 		return (year: comps.year!, month: comps.month!, day: comps.day!)
-	}    
+	}
+
+    func getPersianDate(year: Int, month: Int, day: Int) -> Date? {
+        let dateFormatter = DateFormatter()
+        dateFormatter.dateFormat = "yyyy-MM-dd"
+        dateFormatter.timeZone = TimeZone(abbreviation: "GMT")
+
+        let persianDate = "\(year)/\(month)/\(day)"
+        let date = dateFormatter.date(from: persianDate)
+        return date
+    }
+
+    func convertToGregorian(year: Int, month: Int, day: Int) -> Date? {
+        guard let persianDate = getPersianDate(year: year, month: month, day: day) else {return nil}
+        let dateFormatter = DateFormatter()
+        dateFormatter.dateFormat = "yyyy-MM-dd"
+
+        let gregorianDateString = dateFormatter.string(from: persianDate)
+        dateFormatter.calendar = Calendar(identifier: .persian)
+        dateFormatter.timeZone = TimeZone(abbreviation: "GMT")
+        return dateFormatter.date(from: gregorianDateString)
+    }
+
+    func nextDay(by date: Date) -> Date {
+        return cal.date(byAdding: .day, value: 1, to: date)!
+    }
+
+    func backDay(by date: Date) -> Date {
+        return cal.date(byAdding: .day, value: -1, to: date)!
+    }
 }

PersianDatePicker/PersianDatePickerView.swift

@@ -75,6 +75,22 @@ public class PersianDatePickerView: UIView {
         setDatePicker(year: year, month: month, day: day)
     }
 
+    public func getGregorianDate() -> Date? {
+        return persianDateDataSource.convertToGregorian(year: year, month: month, day: day)
+    }
+
+    public func getPersianDate() -> Date? {
+        return persianDateDataSource.getPersianDate(year: year, month: month, day: day)
+    }
+
+    public func nextDay(by date: Date) -> Date {
+        return persianDateDataSource.nextDay(by: date)
+    }
+
+    public func backDay(by date: Date) -> Date {
+        return persianDateDataSource.backDay(by:date)
+    }
+
     private func setDatePicker(year: Int, month: Int, day: Int) {
         let yearIndex = persianDateDataSource.years.index(of: year)!
         let monthIndex = month - 1