fix: update followState when view will appear

Mastodon/Diffiable/Item/SelectedAccountItem.swift

@@ -5,8 +5,8 @@
 //  Created by sxiaojian on 2021/4/22.
 //
 
-import Foundation
 import CoreData
+import Foundation
 
 enum SelectedAccountItem {
     case accountObjectID(accountObjectID: NSManagedObjectID)

Mastodon/Diffiable/Section/SelectedAccountSection.swift

@@ -26,7 +26,7 @@ extension SelectedAccountSection {
             case .accountObjectID(let objectID):
                 let user = managedObjectContext.object(with: objectID) as! MastodonUser
                 cell.config(with: user)
-            case .placeHolder( _):
+            case .placeHolder:
                 cell.configAsPlaceHolder()
             }
             return cell

Mastodon/Scene/SuggestionAccount/CollectionViewCell/SuggestionAccountCollectionViewCell.swift

@@ -5,9 +5,9 @@
 //  Created by sxiaojian on 2021/4/22.
 //
 
+import CoreDataStack
 import Foundation
 import UIKit
-import CoreDataStack
 
 class SuggestionAccountCollectionViewCell: UICollectionViewCell {
     let imageView: UIImageView = {
@@ -18,11 +18,12 @@ class SuggestionAccountCollectionViewCell: UICollectionViewCell {
         imageView.image = UIImage.placeholder(color: .systemFill)
         return imageView
     }()
-    
+
     func configAsPlaceHolder() {
         imageView.tintColor = Asset.Colors.Label.tertiary.color
         imageView.image = UIImage.placeholder(color: .systemFill)
     }
+
     func config(with mastodonUser: MastodonUser) {
         imageView.af.setImage(
             withURL: URL(string: mastodonUser.avatar)!,
@@ -30,15 +31,16 @@ class SuggestionAccountCollectionViewCell: UICollectionViewCell {
             imageTransition: .crossDissolve(0.2)
         )
     }
+
     override func prepareForReuse() {
         super.prepareForReuse()
     }
-    
+
     override init(frame: CGRect) {
         super.init(frame: .zero)
         configure()
     }
-    
+
     required init?(coder: NSCoder) {
         super.init(coder: coder)
         configure()
@@ -46,7 +48,6 @@ class SuggestionAccountCollectionViewCell: UICollectionViewCell {
 }
 
 extension SuggestionAccountCollectionViewCell {
-    
     private func configure() {
         contentView.addSubview(imageView)
         imageView.translatesAutoresizingMaskIntoConstraints = false

Mastodon/Scene/SuggestionAccount/SuggestionAccountViewController.swift

@@ -90,7 +90,7 @@ extension SuggestionAccountViewController {
         )
 
         viewModel.collectionDiffableDataSource = SelectedAccountSection.collectionViewDiffableDataSource(for: selectedCollectionView, managedObjectContext: context.managedObjectContext)
-    
+
         viewModel.accounts
             .receive(on: DispatchQueue.main)
             .sink { [weak self] accounts in
@@ -103,7 +103,9 @@ extension SuggestionAccountViewController {
     override func viewWillAppear(_ animated: Bool) {
         super.viewWillAppear(animated)
         tableView.deselectRow(with: transitionCoordinator, animated: animated)
+        viewModel.checkAccountsFollowState()
     }
+
     override func viewWillLayoutSubviews() {
         super.viewWillLayoutSubviews()
         let avatarImageViewHeight: Double = 56
@@ -111,6 +113,7 @@ extension SuggestionAccountViewController {
         viewModel.headerPlaceholderCount = avatarImageViewCount
         viewModel.applySelectedCollectionViewDataSource(accounts: [])
     }
+
     func setupHeader(accounts: [NSManagedObjectID]) {
         if accounts.isEmpty {
             return
@@ -138,15 +141,14 @@ extension SuggestionAccountViewController {
 }
 
 extension SuggestionAccountViewController: UICollectionViewDelegateFlowLayout {
-
     func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat {
-        return 15
+        15
     }
 
     func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
-        return CGSize(width: 56, height: 56)
+        CGSize(width: 56, height: 56)
     }
-    
+
     func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
         guard let diffableDataSource = viewModel.collectionDiffableDataSource else { return }
         guard let item = diffableDataSource.itemIdentifier(for: indexPath) else { return }
@@ -195,7 +197,7 @@ extension SuggestionAccountViewController: SuggestionAccountTableViewCellDelegat
                     cell.button.isSelected = selected
                     self.viewModel.selectedAccountsDidChange.send()
                 }
-            }, receiveValue: { relationShip in
+            }, receiveValue: { _ in
             })
             .store(in: &disposeBag)
     }

Mastodon/Scene/SuggestionAccount/SuggestionAccountViewModel.swift

@@ -23,6 +23,7 @@ final class SuggestionAccountViewModel: NSObject {
     // input
     let context: AppContext
     
+    let currentMastodonUser = CurrentValueSubject<MastodonUser?, Never>(nil)
     weak var delegate: SuggestionAccountViewModelDelegate?
     // output
     let accounts = CurrentValueSubject<[NSManagedObjectID], Never>([])
@@ -60,11 +61,23 @@ final class SuggestionAccountViewModel: NSObject {
         
         selectedAccountsDidChange
             .sink { [weak self] _ in
-                if let selectedAccout = self?.selectedAccounts {
+                guard let self = self else { return }
-                    self?.applySelectedCollectionViewDataSource(accounts: selectedAccout)
+                self.applyTableViewDataSource(accounts: self.accounts.value)
-                }
+                self.applySelectedCollectionViewDataSource(accounts: self.selectedAccounts)
             }
             .store(in: &disposeBag)
+        
+        context.authenticationService.activeMastodonAuthentication
+            .sink { [weak self] activeMastodonAuthentication in
+                guard let self = self else { return }
+                guard let activeMastodonAuthentication = activeMastodonAuthentication else {
+                    self.currentMastodonUser.value = nil
+                    return
+                }
+                self.currentMastodonUser.value = activeMastodonAuthentication.user
+            }
+            .store(in: &disposeBag)
+        
         if accounts == nil || (accounts ?? []).isEmpty {
             guard let activeMastodonAuthenticationBox = context.authenticationService.activeMastodonAuthenticationBox.value else { return }
 
@@ -174,4 +187,17 @@ final class SuggestionAccountViewModel: NSObject {
             needFeedback: false
         )
     }
+    
+    func checkAccountsFollowState() {
+        guard let currentMastodonUser = currentMastodonUser.value else {
+            return
+        }
+        let users = accounts.value.compactMap { context.managedObjectContext.object(with: $0) as? MastodonUser }
+        let followingUsers = users.filter { user -> Bool in
+            let isFollowing = user.followingBy.flatMap { $0.contains(currentMastodonUser) } ?? false
+            return isFollowing
+        }.map(\.objectID)
+        selectedAccounts = followingUsers
+        selectedAccountsDidChange.send()
+    }
 }

Mastodon/Scene/SuggestionAccount/TableViewCell/SuggestionAccountTableViewCell.swift

@@ -101,14 +101,14 @@ extension SuggestionAccountTableViewCell {
             containerStackView.topAnchor.constraint(equalTo: contentView.topAnchor),
             containerStackView.leadingAnchor.constraint(equalTo: contentView.leadingAnchor),
             containerStackView.trailingAnchor.constraint(equalTo: contentView.trailingAnchor),
-            containerStackView.bottomAnchor.constraint(equalTo: contentView.bottomAnchor)
+            containerStackView.bottomAnchor.constraint(equalTo: contentView.bottomAnchor),
         ])
         
         _imageView.translatesAutoresizingMaskIntoConstraints = false
         containerStackView.addArrangedSubview(_imageView)
         NSLayoutConstraint.activate([
             _imageView.widthAnchor.constraint(equalToConstant: 42).priority(.required - 1),
-            _imageView.heightAnchor.constraint(equalToConstant: 42).priority(.required - 1)
+            _imageView.heightAnchor.constraint(equalToConstant: 42).priority(.required - 1),
         ])
         
         let textStackView = UIStackView()
@@ -178,7 +178,6 @@ extension SuggestionAccountTableViewCell {
                 self?.button.isHidden = !isHidden
             }
             .store(in: &disposeBag)
-
     }
     
     func startAnimating() {