//
//  RechargeManager.swift
//  FastMeow
//
//  Created by caoyicheng on 2022/2/26.
//

import UIKit
import StoreKit

enum SIAPPurchType {
    case Success       // 购买成功
    case Failed        // 购买失败
    case Cancle        // 取消购买
    case VerFailed     // 订单校验失败
    case VerSuccess    // 订单校验成功
    case NotAllow      // 不允许内购
}

private let RechargeInstance = RechargeManager()

class RechargeManager: NSObject, SKPaymentTransactionObserver, SKProductsRequestDelegate {
    
    typealias RechargeManagerBlock = (_ type: SIAPPurchType, _ data: Data?) -> Void
    
    
    var statusBlock: RechargeManagerBlock!
    var purchID: String!
    // MARK: ======================================生命周期========================================
    
    class var share: RechargeManager {
        
        let obj = RechargeInstance
        obj.initAction()
        return obj
    }
    
    // MARK: 初始化
    @objc func initAction() {
        
        SKPaymentQueue.default().add(self)
        
    }
    
    // MARK: 开始内购
    func startPurchWithID(purchID: String, completeHandle: @escaping RechargeManagerBlock) {
        
        if SKPaymentQueue.canMakePayments() {
            
            self.purchID = purchID
            self.statusBlock = completeHandle
            let request = SKProductsRequest.init(productIdentifiers: [purchID])
            request.delegate = self
            request.start()
            
        } else {
            completeHandle(.NotAllow, nil)
        }
        
    }
    
    // MARK: 交易结束
    func completeTransaction(transaction: SKPaymentTransaction) {
        
        let productIdentifier = transaction.payment.productIdentifier
        
        if productIdentifier.count > 0 {
            
            // 向自己的服务器验证购买凭证
        }
        
        self.verifyPurchaseWithPaymentTransaction(transaction: transaction, isTestServer: false)
        
    }
    
    // MARK: 验证交易
    func verifyPurchaseWithPaymentTransaction(transaction: SKPaymentTransaction, isTestServer: Bool) {
        
        let recepitURL = Bundle.main.appStoreReceiptURL
        do {
            
            let receipt = try Data(contentsOf: recepitURL!)
            
            // 购买成功
            self.statusBlock(.Success, receipt)
            
            // 购买成功将交易凭证发送给服务端进行再次校验
            self.toServiceVerifyPurchaseWithPaymentTransaction(receipt: receipt, transaction: transaction, isTestServer: false)
            
        } catch {
            
            // 交易失败
            self.statusBlock(.Failed, nil)
        }
        
        
        
    }
    
    // MARK: 再次向服务器验证交易
    func toServiceVerifyPurchaseWithPaymentTransaction(receipt: Data, transaction: SKPaymentTransaction, isTestServer: Bool) {
        
        do {
            
            let requestContents = ["receipt-data" : receipt.base64EncodedString()]
            let requestData = try JSONSerialization.data(withJSONObject: requestContents, options: .prettyPrinted)
            
            let serverString = isTestServer ? "https://sandbox.itunes.apple.com/verifyReceipt" : "https://buy.itunes.apple.com/verifyReceipt"
            let storeURL = URL.init(string: serverString)
            var storeRequest = URLRequest.init(url: storeURL!)
            storeRequest.httpMethod = "POST"
            storeRequest.httpBody = requestData

            
            URLSession.shared.dataTask(with: storeRequest) { responseData, response, connectionError in
                
                if connectionError != nil {
                    
                    // 无法连接服务器,购买校验失败
                    self.statusBlock(.VerFailed, nil)
                    
                } else {
                    
                    do {
                        try JSONSerialization.jsonObject(with: responseData!, options: .mutableContainers)
                        let jsonResponse = try JSONSerialization.jsonObject(with: responseData!, options: .mutableContainers) as! [String : Any]
                        
                        // 先验证正式服务器,如果正式服务器返回21007再去苹果测试服务器验证,沙盒测试环境苹果用的是测试服务器
                        let status = String.init(format: "%@", jsonResponse["status"] as! CVarArg)
                        if status == "21007" {
                            
                            self.verifyPurchaseWithPaymentTransaction(transaction: transaction, isTestServer: true)
                        } else {
                            
                            self.statusBlock(.VerSuccess, nil)
                        }
                        
                    } catch {
                        
                        // 苹果服务器校验数据返回为空校验失败
                        self.statusBlock(.VerFailed, nil)
                    }
                    
                }
            }
            
            
        } catch {
            
            // 交易验证失败
            self.statusBlock(.VerFailed, nil)
        }
        
        
        
    }
    
    // MARK: 交易失败
    func failedTransaction(transaction: SKPaymentTransaction) {
        
        self.statusBlock(.Failed, nil)
        
        SKPaymentQueue.default().finishTransaction(transaction)
    }
    
    // MARK: ======================================代理方法========================================

    
    // MARK: 交易状态
    func paymentQueue(_ queue: SKPaymentQueue, updatedTransactions transactions: [SKPaymentTransaction]) {
        
        for transtion in transactions {
            
            if transtion.transactionState == .purchased {
                
                // 购买成功
                self.completeTransaction(transaction: transtion)
                
            } else if transtion.transactionState == .purchasing {
                
                // 正在购买
                
            } else if transtion.transactionState == .restored {
                
                // 恢复
                SKPaymentQueue.default().finishTransaction(transtion)
                
            } else if transtion.transactionState == .failed {
                
                // 购买失败
                self.failedTransaction(transaction: transtion)
                
            } else {
                
                
            }
            
        }
    }
    
    // MARK: 请求查看存在的产品
    func productsRequest(_ request: SKProductsRequest, didReceive response: SKProductsResponse) {
        
        let products = response.products
        if products.count == 0 {
            
            print("没有商品")
            return
        }
        
        var product: SKProduct?
        for item in products {
            
            if item.productIdentifier == self.purchID {
                product = item
                break
            }
        }
        
        if product != nil {
            
            print("产品信息:")
            print(product)
            
            let payment = SKPayment.init(product: product!)
            SKPaymentQueue.default().add(payment)
        }
    }
    
    
    
}

参考文章
https://www.jianshu.com/p/2247f3b36be3