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import Foundation
import UIKit
import StoreKit

class StoreManager:NSObject ,SKProductsRequestDelegate, SKPaymentTransactionObserver{
    static let sharedInstance = StoreManager()
    var transactionInProgress = false
    var productIDs:Array<String!> = ["<App内課金の製品ID>"]
    var productsArray: Array<SKProduct!> = []
    var selectedProductIndex: Int!
    var restore = false
    var payment:SKPayment!

    func requestProductInfo() {
        if SKPaymentQueue.canMakePayments() {
            let productIdentifiers = NSSet(array: StoreManager.sharedInstance.productIDs)
            let productRequest = SKProductsRequest(productIdentifiers: productIdentifiers as! Set<String>)
            productRequest.delegate = self
            productRequest.start()

        }
        else {
            print("Cannot perform In App Purchases.")
        }
    }

    func productsRequest(request: SKProductsRequest, didReceiveResponse response: SKProductsResponse) {
        print("productsRequest")
        if response.products.count != 0 {
            for product in response.products {
                print("validProduct:\(product)")
                StoreManager.sharedInstance.productsArray.append(product)
                self.payment = SKPayment(product: product)
                self.transactionInProgress = true
                SKPaymentQueue.defaultQueue().addPayment(self.payment)
                request.delegate = self
                request.start()
            }
        }
        else {
            print("There are no products.")
        }

        if response.invalidProductIdentifiers.count != 0 {
            print("invalidProductIdnetfiers:\(response.invalidProductIdentifiers.description)")
        }
    }

    // 購入履歴が確認できた場合
    func paymentQueueRestoreCompletedTransactionsFinished(queue: SKPaymentQueue) {
        var restore = false
        print("paymentQueueRestore")

        //すでに商品を購入していたら、復元を行う

        for transaction in queue.transactions {
            print(transaction.payment.productIdentifier)

            if transaction.payment.productIdentifier == "Pro" {
                restore = true

               
            }
        }
  
        if restore == true {
            NSUserDefaults.standardUserDefaults().setBool(true, forKey: "pro")
            let av = UIAlertView(title: "", message: "Restored Successfully", delegate: nil, cancelButtonTitle: "OK")
            av.show()
        }else{
            print("called")
            // failed restore
            let av = UIAlertView(title: "", message: "There is no item to restore", delegate: nil, cancelButtonTitle: "OK")
            av.show()
        }
    }



    func paymentQueue(queue: SKPaymentQueue, updatedTransactions transactions: [SKPaymentTransaction]) {
        print("update Transaction")
      

        for transaction in transactions {
            switch transaction.transactionState {
            case SKPaymentTransactionState.Purchased:
                print("Transaction completed successfully.")
                SKPaymentQueue.defaultQueue().finishTransaction(transaction)
                self.transactionInProgress = false
                NSUserDefaults.standardUserDefaults().setBool(true, forKey: "pro")
                NSUserDefaults.standardUserDefaults().synchronize()

            case SKPaymentTransactionState.Failed:
                print("Transaction Failed");
                SKPaymentQueue.defaultQueue().finishTransaction(transaction)
                self.transactionInProgress = false


            case SKPaymentTransactionState.Purchasing:
                print("purchasing")

            case SKPaymentTransactionState.Restored:
                print("SKPaymentTransactionState.Restored")
                self.transactionInProgress = false
                SKPaymentQueue.defaultQueue().finishTransaction(transaction)
                
            default:
                print("default")
                
            }
        }
    }