[AltStoreCore] Refactors core AltStore logic into AltStoreCore framework

AltStoreCore will contain all shared AltStore code between AltStore and any app extensions. Initially, it includes all AltStore model logic.

AltStoreCore/Patreon/PatreonAPI.swift

@@ -0,0 +1,419 @@
+//
+//  PatreonAPI.swift
+//  AltStore
+//
+//  Created by Riley Testut on 8/20/19.
+//  Copyright © 2019 Riley Testut. All rights reserved.
+//
+
+import Foundation
+import AuthenticationServices
+import CoreData
+
+private let clientID = "ZMx0EGUWe4TVWYXNZZwK_fbIK5jHFVWoUf1Qb-sqNXmT-YzAGwDPxxq7ak3_W5Q2"
+private let clientSecret = "1hktsZB89QyN69cB4R0tu55R4TCPQGXxvebYUUh7Y-5TLSnRswuxs6OUjdJ74IJt"
+
+private let campaignID = "2863968"
+
+extension PatreonAPI
+{
+    enum Error: LocalizedError
+    {
+        case unknown
+        case notAuthenticated
+        case invalidAccessToken
+        
+        var errorDescription: String? {
+            switch self
+            {
+            case .unknown: return NSLocalizedString("An unknown error occurred.", comment: "")
+            case .notAuthenticated: return NSLocalizedString("No connected Patreon account.", comment: "")
+            case .invalidAccessToken: return NSLocalizedString("Invalid access token.", comment: "")
+            }
+        }
+    }
+    
+    enum AuthorizationType
+    {
+        case none
+        case user
+        case creator
+    }
+    
+    enum AnyResponse: Decodable
+    {
+        case tier(TierResponse)
+        case benefit(BenefitResponse)
+        
+        enum CodingKeys: String, CodingKey
+        {
+            case type
+        }
+        
+        init(from decoder: Decoder) throws
+        {
+            let container = try decoder.container(keyedBy: CodingKeys.self)
+            
+            let type = try container.decode(String.self, forKey: .type)
+            switch type
+            {
+            case "tier":
+                let tier = try TierResponse(from: decoder)
+                self = .tier(tier)
+                
+            case "benefit":
+                let benefit = try BenefitResponse(from: decoder)
+                self = .benefit(benefit)
+                
+            default: throw DecodingError.dataCorruptedError(forKey: .type, in: container, debugDescription: "Unrecognized Patreon response type.")
+            }
+        }
+    }
+}
+
+public class PatreonAPI: NSObject
+{
+    public static let shared = PatreonAPI()
+    
+    public var isAuthenticated: Bool {
+        return Keychain.shared.patreonAccessToken != nil
+    }
+    
+    private var authenticationSession: ASWebAuthenticationSession?
+    
+    private let session = URLSession(configuration: .ephemeral)
+    private let baseURL = URL(string: "https://www.patreon.com/")!
+    
+    private override init()
+    {
+        super.init()
+    }
+}
+
+public extension PatreonAPI
+{
+    func authenticate(completion: @escaping (Result<PatreonAccount, Swift.Error>) -> Void)
+    {
+        var components = URLComponents(string: "/oauth2/authorize")!
+        components.queryItems = [URLQueryItem(name: "response_type", value: "code"),
+                                 URLQueryItem(name: "client_id", value: clientID),
+                                 URLQueryItem(name: "redirect_uri", value: "https://rileytestut.com/patreon/altstore")]
+        
+        let requestURL = components.url(relativeTo: self.baseURL)!
+        
+        self.authenticationSession = ASWebAuthenticationSession(url: requestURL, callbackURLScheme: "altstore") { (callbackURL, error) in
+            do
+            {
+                let callbackURL = try Result(callbackURL, error).get()
+                
+                guard
+                    let components = URLComponents(url: callbackURL, resolvingAgainstBaseURL: false),
+                    let codeQueryItem = components.queryItems?.first(where: { $0.name == "code" }),
+                    let code = codeQueryItem.value
+                else { throw Error.unknown }
+                
+                self.fetchAccessToken(oauthCode: code) { (result) in
+                    switch result
+                    {
+                    case .failure(let error): completion(.failure(error))
+                    case .success((let accessToken, let refreshToken)):
+                        Keychain.shared.patreonAccessToken = accessToken
+                        Keychain.shared.patreonRefreshToken = refreshToken
+                        
+                        self.fetchAccount(completion: completion)
+                    }
+                }
+            }
+            catch
+            {
+                completion(.failure(error))
+            }
+        }
+        
+        if #available(iOS 13.0, *)
+        {
+            self.authenticationSession?.presentationContextProvider = self
+        }
+        
+        self.authenticationSession?.start()
+    }
+    
+    func fetchAccount(completion: @escaping (Result<PatreonAccount, Swift.Error>) -> Void)
+    {
+        var components = URLComponents(string: "/api/oauth2/v2/identity")!
+        components.queryItems = [URLQueryItem(name: "include", value: "memberships"),
+                                 URLQueryItem(name: "fields[user]", value: "first_name,full_name"),
+                                 URLQueryItem(name: "fields[member]", value: "full_name,patron_status")]
+        
+        let requestURL = components.url(relativeTo: self.baseURL)!
+        let request = URLRequest(url: requestURL)
+        
+        self.send(request, authorizationType: .user) { (result: Result<AccountResponse, Swift.Error>) in
+            switch result
+            {
+            case .failure(Error.notAuthenticated):
+                self.signOut() { (result) in
+                    completion(.failure(Error.notAuthenticated))
+                }
+                
+            case .failure(let error): completion(.failure(error))
+            case .success(let response):
+                DatabaseManager.shared.persistentContainer.performBackgroundTask { (context) in
+                    let account = PatreonAccount(response: response, context: context)
+                    completion(.success(account))
+                }
+            }
+        }
+    }
+    
+    func fetchPatrons(completion: @escaping (Result<[Patron], Swift.Error>) -> Void)
+    {
+        var components = URLComponents(string: "/api/oauth2/v2/campaigns/\(campaignID)/members")!
+        components.queryItems = [URLQueryItem(name: "include", value: "currently_entitled_tiers,currently_entitled_tiers.benefits"),
+                                 URLQueryItem(name: "fields[tier]", value: "title"),
+                                 URLQueryItem(name: "fields[member]", value: "full_name,patron_status"),
+                                 URLQueryItem(name: "page[size]", value: "1000")]
+        
+        let requestURL = components.url(relativeTo: self.baseURL)!
+        
+        struct Response: Decodable
+        {
+            var data: [PatronResponse]
+            var included: [AnyResponse]
+            var links: [String: URL]?
+        }
+        
+        var allPatrons = [Patron]()
+        
+        func fetchPatrons(url: URL)
+        {
+            let request = URLRequest(url: url)
+            
+            self.send(request, authorizationType: .creator) { (result: Result<Response, Swift.Error>) in
+                switch result
+                {
+                case .failure(let error): completion(.failure(error))
+                case .success(let response):
+                    let tiers = response.included.compactMap { (response) -> Tier? in
+                        switch response
+                        {
+                        case .tier(let tierResponse): return Tier(response: tierResponse)
+                        case .benefit: return nil
+                        }
+                    }
+                    
+                    let tiersByIdentifier = Dictionary(tiers.map { ($0.identifier, $0) }, uniquingKeysWith: { (a, b) in return a })
+                    
+                    let patrons = response.data.map { (response) -> Patron in
+                        let patron = Patron(response: response)
+                        
+                        for tierID in response.relationships?.currently_entitled_tiers.data ?? []
+                        {
+                            guard let tier = tiersByIdentifier[tierID.id] else { continue }
+                            patron.benefits.formUnion(tier.benefits)
+                        }
+                        
+                        return patron
+                    }.filter { $0.benefits.contains(where: { $0.type == .credits }) }
+                    
+                    allPatrons.append(contentsOf: patrons)
+                    
+                    if let nextURL = response.links?["next"]
+                    {
+                        fetchPatrons(url: nextURL)
+                    }
+                    else
+                    {
+                        completion(.success(allPatrons))
+                    }
+                }
+            }
+        }
+        
+        fetchPatrons(url: requestURL)
+    }
+    
+    func signOut(completion: @escaping (Result<Void, Swift.Error>) -> Void)
+    {
+        DatabaseManager.shared.persistentContainer.performBackgroundTask { (context) in
+            do
+            {
+                let accounts = PatreonAccount.all(in: context, requestProperties: [\FetchRequest.returnsObjectsAsFaults: true])
+                accounts.forEach(context.delete(_:))
+                
+                self.deactivateBetaApps(in: context)
+                
+                try context.save()
+                
+                Keychain.shared.patreonAccessToken = nil
+                Keychain.shared.patreonRefreshToken = nil
+                
+                completion(.success(()))
+            }
+            catch
+            {
+                completion(.failure(error))
+            }
+        }
+    }
+    
+    func refreshPatreonAccount()
+    {
+        guard PatreonAPI.shared.isAuthenticated else { return }
+        
+        PatreonAPI.shared.fetchAccount { (result: Result<PatreonAccount, Swift.Error>) in
+            do
+            {
+                let account = try result.get()
+                
+                if let context = account.managedObjectContext, !account.isPatron
+                {
+                    // Deactivate all beta apps now that we're no longer a patron.
+                    self.deactivateBetaApps(in: context)
+                }
+                
+                try account.managedObjectContext?.save()
+            }
+            catch
+            {
+                print("Failed to fetch Patreon account.", error)
+            }
+        }
+    }
+}
+
+private extension PatreonAPI
+{
+    func fetchAccessToken(oauthCode: String, completion: @escaping (Result<(String, String), Swift.Error>) -> Void)
+    {
+        let encodedRedirectURI = ("https://rileytestut.com/patreon/altstore" as NSString).addingPercentEncoding(withAllowedCharacters: .alphanumerics)!
+        let encodedOauthCode = (oauthCode as NSString).addingPercentEncoding(withAllowedCharacters: .alphanumerics)!
+        
+        let body = "code=\(encodedOauthCode)&grant_type=authorization_code&client_id=\(clientID)&client_secret=\(clientSecret)&redirect_uri=\(encodedRedirectURI)"
+        
+        let requestURL = URL(string: "/api/oauth2/token", relativeTo: self.baseURL)!
+        
+        var request = URLRequest(url: requestURL)
+        request.httpMethod = "POST"
+        request.httpBody = body.data(using: .utf8)
+        request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
+        
+        struct Response: Decodable
+        {
+            var access_token: String
+            var refresh_token: String
+        }
+        
+        self.send(request, authorizationType: .none) { (result: Result<Response, Swift.Error>) in
+            switch result
+            {
+            case .failure(let error): completion(.failure(error))
+            case .success(let response): completion(.success((response.access_token, response.refresh_token)))
+            }
+        }
+    }
+    
+    func refreshAccessToken(completion: @escaping (Result<Void, Swift.Error>) -> Void)
+    {
+        guard let refreshToken = Keychain.shared.patreonRefreshToken else { return }
+        
+        var components = URLComponents(string: "/api/oauth2/token")!
+        components.queryItems = [URLQueryItem(name: "grant_type", value: "refresh_token"),
+                                 URLQueryItem(name: "refresh_token", value: refreshToken),
+                                 URLQueryItem(name: "client_id", value: clientID),
+                                 URLQueryItem(name: "client_secret", value: clientSecret)]
+        
+        let requestURL = components.url(relativeTo: self.baseURL)!
+        
+        var request = URLRequest(url: requestURL)
+        request.httpMethod = "POST"
+        
+        struct Response: Decodable
+        {
+            var access_token: String
+            var refresh_token: String
+        }
+        
+        self.send(request, authorizationType: .none) { (result: Result<Response, Swift.Error>) in
+            switch result
+            {
+            case .failure(let error): completion(.failure(error))
+            case .success(let response):
+                Keychain.shared.patreonAccessToken = response.access_token
+                Keychain.shared.patreonRefreshToken = response.refresh_token
+                
+                completion(.success(()))
+            }
+        }
+    }
+    
+    func send<ResponseType: Decodable>(_ request: URLRequest, authorizationType: AuthorizationType, completion: @escaping (Result<ResponseType, Swift.Error>) -> Void)
+    {
+        var request = request
+        
+        switch authorizationType
+        {
+        case .none: break
+        case .creator:
+            guard let creatorAccessToken = Keychain.shared.patreonCreatorAccessToken else { return completion(.failure(Error.invalidAccessToken)) }
+            request.setValue("Bearer " + creatorAccessToken, forHTTPHeaderField: "Authorization")
+            
+        case .user:
+            guard let accessToken = Keychain.shared.patreonAccessToken else { return completion(.failure(Error.notAuthenticated)) }
+            request.setValue("Bearer " + accessToken, forHTTPHeaderField: "Authorization")
+        }
+        
+        let task = self.session.dataTask(with: request) { (data, response, error) in
+            do
+            {
+                let data = try Result(data, error).get()
+                
+                if let response = response as? HTTPURLResponse, response.statusCode == 401
+                {
+                    switch authorizationType
+                    {
+                    case .creator: completion(.failure(Error.invalidAccessToken))
+                    case .none: completion(.failure(Error.notAuthenticated))
+                    case .user:
+                        self.refreshAccessToken() { (result) in
+                            switch result
+                            {
+                            case .failure(let error): completion(.failure(error))
+                            case .success: self.send(request, authorizationType: authorizationType, completion: completion)
+                            }
+                        }
+                    }
+                    
+                    return
+                }
+                
+                let response = try JSONDecoder().decode(ResponseType.self, from: data)
+                completion(.success(response))
+            }
+            catch let error
+            {
+                completion(.failure(error))
+            }
+        }
+        
+        task.resume()
+    }
+    
+    func deactivateBetaApps(in context: NSManagedObjectContext)
+    {
+        let predicate = NSPredicate(format: "%K != %@ AND %K != nil AND %K == YES",
+                                    #keyPath(InstalledApp.bundleIdentifier), StoreApp.altstoreAppID, #keyPath(InstalledApp.storeApp), #keyPath(InstalledApp.storeApp.isBeta))
+        
+        let installedApps = InstalledApp.all(satisfying: predicate, in: context)
+        installedApps.forEach { $0.isActive = false }
+    }
+}
+
+@available(iOS 13.0, *)
+extension PatreonAPI: ASWebAuthenticationPresentationContextProviding
+{
+    public func presentationAnchor(for session: ASWebAuthenticationSession) -> ASPresentationAnchor
+    {
+        return UIApplication.alt_shared?.keyWindow ?? UIWindow()
+    }
+}