homework_8

TinkoffChat/Core Layer/IdentifierGenerator.swift

@@ -0,0 +1,19 @@
+//
+// IdentifierGenerator.swift
+// TinkoffChat
+//
+// Created by Nikita Borodulin on 10/11/2017.
+// Copyright © 2017 com.nikitaborodulin. All rights reserved.
+//
+
+import Foundation
+
+protocol IIdentifierGenerator: class {
+ func generateIdentifier() -> String
+}
+
+class IdentifierGenerator: IIdentifierGenerator {
+ func generateIdentifier() -> String {
+ return ("\(arc4random_uniform(UINT32_MAX)) + \(Date.timeIntervalSinceReferenceDate) + \(arc4random_uniform(UINT32_MAX))".data(using: .utf8)?.base64EncodedString())!
+ }
+}

TinkoffChat/Core Layer/Multipeer Communicator/ICommunicator.swift

@@ -9,7 +9,7 @@
 import MultipeerConnectivity
 
 protocol ICommunicator: class {
- func sendMessage(text: String, to userID: String, completionHandler: ((_ success: Bool, _ error: Error?) -> Void)?)
+ func sendMessage(text: String, to userID: String) throws
  weak var delegate: ICommunicatorDelegate? { get set }
 }
 

TinkoffChat/Core Layer/Multipeer Communicator/MessageEncoder.swift

@@ -18,9 +18,15 @@ class MessageEncoder: IMessageEncoder {
  private static let messageIdKey = "messageId"
  private static let messageTextKey = "text"
 
+ private let identifierGenerator: IIdentifierGenerator
+
+ init(_ identifierGenerator: IIdentifierGenerator) {
+ self.identifierGenerator = identifierGenerator
+ }
+
  func prepareForSend(text: String) -> Data? {
  let message = [MessageEncoder.messageEventTypeKey: MessageEncoder.messageEventTypeDescription,
- MessageEncoder.messageIdKey: generateIdentifier(),
+ MessageEncoder.messageIdKey: identifierGenerator.generateIdentifier(),
  MessageEncoder.messageTextKey: text]
  do {
  let messageData = try JSONSerialization.data(withJSONObject: message, options: .prettyPrinted)
@@ -30,8 +36,4 @@ class MessageEncoder: IMessageEncoder {
  }
  return nil
  }
-
- private func generateIdentifier() -> String {
- return ("\(arc4random_uniform(UINT32_MAX)) + \(Date.timeIntervalSinceReferenceDate) + \(arc4random_uniform(UINT32_MAX))".data(using: .utf8)?.base64EncodedString())!
- }
 }

TinkoffChat/Core Layer/Multipeer Communicator/MultipeerCommunicator.swift

@@ -13,7 +13,6 @@ class MultipeerCommunicator: NSObject {
  enum MultipeerCommunicatorError: Error {
  case communicatorInternalError
  case communicatorMessageEncodingError
- case communicatorCantSend
  }
 
  weak var delegate: ICommunicatorDelegate?
@@ -27,6 +26,7 @@ class MultipeerCommunicator: NSObject {
 
  private var sessionsByPeerID = [MCPeerID: MCSession]()
  private var foundPeers = [MCPeerID: [String: String]?]()
+ private var connectedPeers = Set<MCPeerID>()
 
  init(_ messageHandler: IMessageHandler) {
  self.messageHandler = messageHandler
@@ -71,20 +71,17 @@ class MultipeerCommunicator: NSObject {
 // MARK: ICommunicator
 
 extension MultipeerCommunicator: ICommunicator {
- func sendMessage(text: String, to userID: String, completionHandler: ((_ success: Bool, _ error: Error?) -> Void)?) {
+ func sendMessage(text: String, to userID: String) throws {
  guard let peerID = getPeerIDFor(userID), let session = sessionsByPeerID[peerID] else {
- completionHandler?(false, MultipeerCommunicatorError.communicatorInternalError)
- return
+ throw MultipeerCommunicatorError.communicatorInternalError
  }
  guard let serializedMessage = messageHandler.prepareForSend(text: text) else {
- completionHandler?(false, MultipeerCommunicatorError.communicatorMessageEncodingError)
- return
+ throw MultipeerCommunicatorError.communicatorMessageEncodingError
  }
  do {
  try session.send(serializedMessage, toPeers: [peerID], with: .reliable)
- completionHandler?(true, nil)
  } catch {
- completionHandler?(false, error)
+ print("Failed to send message \(error)")
  }
  }
 }
@@ -97,13 +94,14 @@ extension MultipeerCommunicator: MCNearbyServiceBrowserDelegate {
  print("found peer \(peerID.displayName)")
  foundPeers[peerID] = info
  let session = getSessionFor(peerID) ?? createNewSession(for: peerID)
+
  browser.invitePeer(peerID, to: session, withContext: nil, timeout: MultipeerCommunicator.peerInvitationTimeout)
  print("invited peer \(peerID.displayName)")
  }
 
  func browser(_ browser: MCNearbyServiceBrowser, lostPeer peerID: MCPeerID) {
  print("lost \(peerID.displayName)")
- if sessionsByPeerID.removeValue(forKey: peerID) != nil {
+ if connectedPeers.remove(peerID) != nil {
  delegate?.didLoseUser(userID: peerID.displayName)
  }
  }
@@ -135,7 +133,11 @@ extension MultipeerCommunicator: MCSessionDelegate {
  print("Couldn't decode message from \(peerID.displayName)")
  return
  }
- delegate?.didReceiveMessage(text: message, fromUser: peerID.displayName, toUser: myPeerID.displayName)
+ if connectedPeers.contains(peerID) {
+ delegate?.didReceiveMessage(text: message, fromUser: peerID.displayName, toUser: myPeerID.displayName)
+ } else {
+ print("Received message from not connected peer ¯\\_(ツ)_/¯")
+ }
  }
 
  func session(_ session: MCSession, peer peerID: MCPeerID, didChange state: MCSessionState) {
@@ -145,12 +147,14 @@ extension MultipeerCommunicator: MCSessionDelegate {
  if let peerDiscoveryInfo = foundPeers[peerID] {
  print("connected with \(peerID.displayName)")
  delegate?.didFindUser(userID: peerID.displayName, userName: peerDiscoveryInfo?[discoveryInfoUserNameKey])
+ connectedPeers.insert(peerID)
  }
  case .notConnected:
  print("not connected with \(peerID.displayName)")
- if sessionsByPeerID.removeValue(forKey: peerID) != nil {
+ if connectedPeers.remove(peerID) != nil {
  delegate?.didLoseUser(userID: peerID.displayName)
  }
+ sessionsByPeerID.removeValue(forKey: peerID)
  foundPeers.removeValue(forKey: peerID)
  session.disconnect()
  case .connecting:

TinkoffChat/Core Layer/Storage/Core Data Profile Storage/CoreDataStack.swift → TinkoffChat/Core Layer/Storage/CoreDataStack.swift

@@ -43,10 +43,8 @@ class CoreDataStack: ICoreDataStack {
  }()
 
  func performSave(in context: NSManagedObjectContext, completionHandler: (() -> Void)?) {
- if context.hasChanges {
-// No need for a capture list in the block below. As soon as the block finishes executing, context releases it.
-// The block's retain count becomes zero and it is deallocated. When it deallocates, it releases 'self'.
- context.perform {
+ context.perform {
+ if context.hasChanges {
  do {
  try context.save()
  } catch {
@@ -57,9 +55,9 @@ class CoreDataStack: ICoreDataStack {
  } else {
  completionHandler?()
  }
+ } else {
+ completionHandler?()
  }
- } else {
- completionHandler?()
  }
  }
 
@@ -91,8 +89,7 @@ class CoreDataStack: ICoreDataStack {
  configurationName: nil,
  at: persistentStoreURL,
  options: nil)
- }
- catch {
+ } catch {
  fatalError("Unable to Load Persistent Store")
  }
  return persistentStoreCoordinator

TinkoffChat/Core Layer/Storage/Core Data Profile Storage/AppUser.swift → TinkoffChat/Core Layer/Storage/MO Extensions/AppUser.swift

@@ -14,21 +14,26 @@ extension AppUser {
  private static let appUserDefaultID = UIDevice.current.identifierForVendor!.uuidString
 
  static func findOrInsertAppUser(in context: NSManagedObjectContext) -> AppUser {
+ if let fetchedAppUser = fetchAppUser(in: context) {
+ return fetchedAppUser
+ } else {
+ let newAppUser = AppUser.insertAppUser(in: context)
+ return newAppUser
+ }
+ }
+
+ private static func fetchAppUser(in context: NSManagedObjectContext) -> AppUser? {
  guard let model = context.persistentStoreCoordinator?.managedObjectModel else {
  preconditionFailure("Model is not available in context")
-
  }
- var foundAppUser: AppUser?
-
  let fetchRequest = AppUser.fetchRequestAppUser(model: model)
  do {
  let results = try context.fetch(fetchRequest)
  assert(results.count < 2, "Multiple AppUsers found")
- foundAppUser = results.first
+ return results.first
  } catch {
- print("Failed to fetch AppUser \(error)")
+ fatalError("Failed to fetch AppUser: \(error)")
  }
- return foundAppUser ?? AppUser.insertAppUser(in: context)
  }
 
  private static func insertAppUser(in context: NSManagedObjectContext) -> AppUser {

TinkoffChat/Core Layer/Storage/MO Extensions/Conversation.swift

@@ -0,0 +1,50 @@
+//
+// Conversation.swift
+// TinkoffChat
+//
+// Created by Nikita Borodulin on 10/11/2017.
+// Copyright © 2017 com.nikitaborodulin. All rights reserved.
+//
+
+import CoreData
+
+extension Conversation {
+ private static let fetchRequestConversationByIDTemplateName = "ConversationByID"
+ private static let fetchRequestConversationByIDAttributeName = "conversationID"
+
+ static func findOrInsertConversationWith(id: String, in context: NSManagedObjectContext) -> Conversation {
+ if let fetchedConversation = fetchConversationWith(id: id, in: context) {
+ return fetchedConversation
+ } else {
+ let newConversation = Conversation.insertConversationWith(id: id, in: context)
+ return newConversation
+ }
+ }
+
+ private static func fetchConversationWith(id: String, in context: NSManagedObjectContext) -> Conversation? {
+ guard let model = context.persistentStoreCoordinator?.managedObjectModel else {
+ preconditionFailure("Model is not available in context")
+ }
+ let fetchRequest = Conversation.fetchRequestConversationBy(id: id, model: model)
+ do {
+ let results = try context.fetch(fetchRequest)
+ assert(results.count < 2, "Multiple Conversations found for id: \(id)")
+ return results.first
+ } catch {
+ fatalError("Failed to fetch User with id: \(id) \(error)")
+ }
+ }
+
+ private static func insertConversationWith(id: String, in context: NSManagedObjectContext) -> Conversation {
+ let newConversation = Conversation(context: context)
+ newConversation.conversationID = id
+ return newConversation
+ }
+
+ private static func fetchRequestConversationBy(id: String, model: NSManagedObjectModel) -> NSFetchRequest<Conversation> {
+ guard let fetchRequest = model.fetchRequestFromTemplate(withName: fetchRequestConversationByIDTemplateName, substitutionVariables: [fetchRequestConversationByIDAttributeName: id]) as? NSFetchRequest<Conversation> else {
+ preconditionFailure("No template with \(fetchRequestConversationByIDTemplateName) name")
+ }
+ return fetchRequest
+ }
+}

TinkoffChat/Core Layer/Storage/MO Extensions/Message.swift

@@ -0,0 +1,24 @@
+//
+// Message.swift
+// TinkoffChat
+//
+// Created by Nikita Borodulin on 12/11/2017.
+// Copyright © 2017 com.nikitaborodulin. All rights reserved.
+//
+
+import CoreData
+
+extension Message {
+ private static let fetchRequestMessageByIDTemplateName = "MessagesByConversationID"
+ private static let fetchRequestMessageByIDAttributeName = "id"
+
+ static func fetchRequestMessage(withConversationID conversationID: String, in context: NSManagedObjectContext) -> NSFetchRequest<Message> {
+ guard let model = context.persistentStoreCoordinator?.managedObjectModel else {
+ preconditionFailure("Model is not available in context")
+ }
+ guard let fetchRequest = model.fetchRequestFromTemplate(withName: fetchRequestMessageByIDTemplateName, substitutionVariables: [fetchRequestMessageByIDAttributeName: conversationID]) as? NSFetchRequest<Message> else {
+ preconditionFailure("No template with \(fetchRequestMessageByIDTemplateName) name")
+ }
+ return fetchRequest
+ }
+}

TinkoffChat/Core Layer/Storage/Core Data Profile Storage/User.swift → TinkoffChat/Core Layer/Storage/MO Extensions/User.swift

@@ -10,28 +10,29 @@ import CoreData
 
 extension User {
  private static let fetchRequestUserByIDTemplateName = "UserByID"
- private static let fetchRequestUserByIDAttributeName = "id"
+ private static let fetchRequestUserByIDAttributeName = "userID"
 
- static func findOrInsertUserWith(id: String, in context: NSManagedObjectContext) -> User? {
+ static func findOrInsertUserWith(id: String, in context: NSManagedObjectContext) -> User {
+ if let fetchedUser = fetchUserWith(id: id, in: context) {
+ return fetchedUser
+ } else {
+ let newUser = User.insertUserWith(id: id, in: context)
+ return newUser
+ }
+ }
+
+ private static func fetchUserWith(id: String, in context: NSManagedObjectContext) -> User? {
  guard let model = context.persistentStoreCoordinator?.managedObjectModel else {
- assertionFailure("Model is not available in context")
- return nil
+ preconditionFailure("Model is not available in context")
  }
- var user: User?
  let fetchRequest = User.fetchRequestUserBy(id: id, model: model)
  do {
  let results = try context.fetch(fetchRequest)
  assert(results.count < 2, "Multiple AppUsers found")
- if let foundUser = results.first {
- user = foundUser
- }
+ return results.first
  } catch {
- print("Failed to fetch User with id: \(id) \(error)")
+ fatalError("Failed to fetch User with id: \(id) \(error)")
  }
- if user == nil {
- user = User.insertUserWith(id: id, in: context)
- }
- return user
  }
 
  private static func insertUserWith(id: String, in context: NSManagedObjectContext) -> User {

TinkoffChat/Core Layer/Storage/Model.xcdatamodeld/Model.xcdatamodel/contents

@@ -3,20 +3,41 @@
  <entity name="AppUser" representedClassName="AppUser" syncable="YES" codeGenerationType="class">
  <relationship name="currentUser" maxCount="1" deletionRule="Nullify" destinationEntity="User" inverseName="appUser" inverseEntity="User" syncable="YES"/>
  </entity>
+ <entity name="Conversation" representedClassName="Conversation" syncable="YES" codeGenerationType="class">
+ <attribute name="conversationID" attributeType="String" syncable="YES"/>
+ <attribute name="isOnline" attributeType="Boolean" usesScalarValueType="YES" syncable="YES"/>
+ <attribute name="isUnread" attributeType="Boolean" defaultValueString="NO" usesScalarValueType="YES" syncable="YES"/>
+ <relationship name="lastMessage" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="Message" inverseName="lastMessageInConversation" inverseEntity="Message" syncable="YES"/>
+ <relationship name="messages" optional="YES" toMany="YES" deletionRule="Nullify" destinationEntity="Message" inverseName="conversation" inverseEntity="Message" syncable="YES"/>
+ <relationship name="participant" maxCount="1" deletionRule="Nullify" destinationEntity="User" inverseName="conversation" inverseEntity="User" syncable="YES"/>
+ </entity>
+ <entity name="Message" representedClassName="Message" syncable="YES" codeGenerationType="class">
+ <attribute name="date" attributeType="Date" usesScalarValueType="NO" syncable="YES"/>
+ <attribute name="isOutgoing" attributeType="Boolean" usesScalarValueType="YES" syncable="YES"/>
+ <attribute name="messageID" attributeType="String" syncable="YES"/>
+ <attribute name="text" optional="YES" attributeType="String" syncable="YES"/>
+ <relationship name="conversation" maxCount="1" deletionRule="Nullify" destinationEntity="Conversation" inverseName="messages" inverseEntity="Conversation" syncable="YES"/>
+ <relationship name="lastMessageInConversation" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="Conversation" inverseName="lastMessage" inverseEntity="Conversation" syncable="YES"/>
+ </entity>
  <entity name="User" representedClassName="User" syncable="YES" codeGenerationType="class">
  <attribute name="info" optional="YES" attributeType="String" syncable="YES"/>
+ <attribute name="isOnline" optional="YES" attributeType="Boolean" usesScalarValueType="YES" syncable="YES"/>
  <attribute name="name" optional="YES" attributeType="String" syncable="YES"/>
  <attribute name="profileImage" optional="YES" attributeType="Binary" syncable="YES"/>
  <attribute name="userID" attributeType="String" syncable="YES"/>
  <relationship name="appUser" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="AppUser" inverseName="currentUser" inverseEntity="AppUser" syncable="YES"/>
- <fetchIndex name="byUserID">
- <fetchIndexElement property="userID" type="Binary" order="ascending"/>
- </fetchIndex>
+ <relationship name="conversation" optional="YES" maxCount="1" deletionRule="Nullify" destinationEntity="Conversation" inverseName="participant" inverseEntity="Conversation" syncable="YES"/>
  </entity>
  <fetchRequest name="AppUser" entity="AppUser"/>
- <fetchRequest name="UserByID" entity="User" predicateString="userID == &quot;$id&quot;"/>
+ <fetchRequest name="ConversationByID" entity="Conversation" predicateString="conversationID == $conversationID"/>
+ <fetchRequest name="ConversationsByOnlineUserID" entity="Conversation" predicateString="participant.isOnline == 1 AND messages != nil"/>
+ <fetchRequest name="MessagesByConversationID" entity="Message" predicateString="conversation.conversationID == $id"/>
+ <fetchRequest name="OnlineUsers" entity="User" predicateString="isOnline == 1"/>
+ <fetchRequest name="UserByID" entity="User" predicateString="userID == $userID"/>
  <elements>
- <element name="AppUser" positionX="-63" positionY="-18" width="128" height="60"/>
- <element name="User" positionX="108" positionY="18" width="128" height="120"/>
+ <element name="AppUser" positionX="-72" positionY="39" width="128" height="60"/>
+ <element name="Conversation" positionX="-63" positionY="180" width="128" height="135"/>
+ <element name="Message" positionX="-243" positionY="176" width="128" height="133"/>
+ <element name="User" positionX="108" positionY="18" width="128" height="148"/>
  </elements>
 </model>