Settings: Switch to UIKit

App/Settings/GeneralSettingsViewController.swift

@@ -0,0 +1,195 @@
+//
+//  GeneralSettingsViewController.swift
+//  GeneralSettingsViewController
+//
+//  Created by James Magahern on 6/25/21.
+//
+
+import UIKit
+
+struct LabelContentConfiguration : UIContentConfiguration
+{
+    var text: String = ""
+    var insets: UIEdgeInsets = .zero
+    var textAlignment: NSTextAlignment = .natural
+        
+    func makeContentView() -> UIView & UIContentView {
+        let label = UILabel(frame: .zero)
+        let contentView = GenericContentView<UILabel, LabelContentConfiguration>(configuration: self, view: label) { config, label in
+            label.text = config.text
+            label.textAlignment = config.textAlignment
+        }
+        contentView.insets = UIEdgeInsets(top: 0, left: 10, bottom: 0, right: 10)
+        return contentView
+    }
+    
+    func updated(for state: UIConfigurationState) -> Self {
+        self
+    }
+}
+
+struct ButtonContentConfiguration : UIContentConfiguration
+{
+    var menu: UIMenu
+    
+    func makeContentView() -> UIView & UIContentView {
+        let button = UIButton(primaryAction: nil)
+        return GenericContentView<UIButton, ButtonContentConfiguration>(configuration: self, view: button) { config, button in
+            button.menu = menu
+            button.showsMenuAsPrimaryAction = true
+            if #available(macCatalyst 15.0, iOS 15.0, *) {
+                var buttonConfiguration = UIButton.Configuration.plain()
+                buttonConfiguration.titleAlignment = .trailing
+                
+                button.configuration = buttonConfiguration
+                button.changesSelectionAsPrimaryAction = true
+            }
+        }
+    }
+    
+    func updated(for state: UIConfigurationState) -> ButtonContentConfiguration {
+        self
+    }
+}
+
+class GeneralSettingsViewController: UIViewController
+{
+    enum Section: String, CaseIterable {
+        case searchEngine = "Search Engine"
+    }
+    
+    typealias Item = String
+    
+    static let SearchProviderPopupItem = "searchProvider.popup"
+    
+    let dataSource: UICollectionViewDiffableDataSource<Section, Item>
+    let collectionView: UICollectionView
+    
+    static func createLayout(forIdiom idiom: UIUserInterfaceIdiom) -> UICollectionViewLayout {
+        if idiom == .mac {
+            let itemSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1.0),
+                                                 heightDimension: .fractionalHeight(1.0))
+            let item = NSCollectionLayoutItem(layoutSize: itemSize)
+
+            let groupSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(0.60),
+                                                  heightDimension: .absolute(44))
+            
+            let group = NSCollectionLayoutGroup.horizontal(layoutSize: groupSize, subitem: item, count: 1)
+            group.edgeSpacing = NSCollectionLayoutEdgeSpacing(leading: .flexible(1.0), top: nil, trailing: nil, bottom: nil)
+            
+            let insets = NSDirectionalEdgeInsets(top: 24.0, leading: 64.0, bottom: 24.0, trailing: 64.0)
+            
+            let headerFooterSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(0.40),
+                                                          heightDimension: .estimated(44.0))
+            let sectionHeader = NSCollectionLayoutBoundarySupplementaryItem(
+                layoutSize: headerFooterSize,
+                elementKind: UICollectionView.elementKindSectionHeader,
+                alignment: .topLeading,
+                absoluteOffset: CGPoint(x: insets.leading, y: insets.top)
+            )
+            sectionHeader.extendsBoundary = false
+            sectionHeader.contentInsets = insets
+
+            let section = NSCollectionLayoutSection(group: group)
+            // section.interGroupSpacing = spacing
+            section.contentInsets = insets
+            section.supplementariesFollowContentInsets = true
+            section.boundarySupplementaryItems = [ sectionHeader ]
+
+            let layout = UICollectionViewCompositionalLayout(section: section)
+            return layout
+        } else {
+            var listConfiguration = UICollectionLayoutListConfiguration(appearance: .insetGrouped)
+            listConfiguration.headerMode = .supplementary
+            return UICollectionViewCompositionalLayout.list(using: listConfiguration)
+        }
+    }
+    
+    static func sectionHeaderConfiguration(forIdiom idiom: UIUserInterfaceIdiom, sectionName: String) -> UIContentConfiguration {
+        if idiom == .mac {
+            return LabelContentConfiguration(
+                text: sectionName + ": ",
+                insets: UIEdgeInsets(top: 0, left: 10.0, bottom: 0, right: 10.0),
+                textAlignment: .right
+            )
+        } else {
+            var config = UIListContentConfiguration.plainHeader()
+            config.text = sectionName
+            return config
+        }
+    }
+
+    #if targetEnvironment(macCatalyst)
+    static let staticIdiom = UIUserInterfaceIdiom.mac
+    #else
+    static let staticIdiom = UIUserInterfaceIdiom.pad
+    #endif
+    
+    init() {
+        let actionHandler = { (action: UIAction) in
+            let providerString = action.title
+            let provider = Settings.SearchProviderSetting(rawValue: providerString)!
+            Settings.shared.searchProvider = provider
+        }
+        
+        let itemCellRegistry = UICollectionView.CellRegistration<UICollectionViewCell, Item> { cell, indexPath, identifier in
+            if identifier == Self.SearchProviderPopupItem {
+                let menu = UIMenu(children: Settings.SearchProviderSetting.allCases.map { provider in
+                    let action = UIAction(title: provider.rawValue, handler: actionHandler)
+                    action.state = Settings.shared.searchProvider == provider ? .on : .off
+                    return action
+                })
+                
+                cell.contentConfiguration = ButtonContentConfiguration(menu: menu)
+                
+                #if !targetEnvironment(macCatalyst)
+                cell.backgroundConfiguration = UIBackgroundConfiguration.listGroupedCell()
+                #endif
+            }
+        }
+                
+        let sectionHeaderRegistry = UICollectionView.SupplementaryRegistration<UICollectionViewCell>(elementKind: UICollectionView.elementKindSectionHeader, handler: {
+        (cell, string, indexPath) in
+            let sectionName = Section.allCases[indexPath.section].rawValue
+            cell.contentConfiguration = Self.sectionHeaderConfiguration(forIdiom: Self.staticIdiom, sectionName: sectionName)
+        })
+        
+        let layout = Self.createLayout(forIdiom: Self.staticIdiom)
+        collectionView = UICollectionView(frame: .zero, collectionViewLayout: layout)
+        collectionView.backgroundColor = .systemGroupedBackground
+        
+        dataSource = UICollectionViewDiffableDataSource<Section, Item>(collectionView: collectionView) {
+        (collectionView, indexPath, identifier) in
+            return collectionView.dequeueConfiguredReusableCell(using: itemCellRegistry, for: indexPath, item: identifier)
+        }
+        
+        dataSource.supplementaryViewProvider = { collectionView, elementKind, indexPath in
+            return collectionView.dequeueConfiguredReusableSupplementary(using: sectionHeaderRegistry, for: indexPath)
+        }
+        
+        super.init(nibName: nil, bundle: nil)
+        
+        tabBarItem.title = "General"
+        tabBarItem.image = UIImage(systemName: "gear")
+    }
+    
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+    
+    override func loadView() {
+        self.view = collectionView
+    }
+    
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        
+        var snapshot = dataSource.snapshot()
+        snapshot.appendSections(Section.allCases)
+        // iOS
+        // snapshot.appendItems(Settings.SearchProviderSetting.allCases.map { $0.rawValue }, toSection: .searchEngine)
+        snapshot.appendItems([ Self.SearchProviderPopupItem ], toSection: .searchEngine)
+        dataSource.apply(snapshot, animatingDifferences: false)
+    }
+
+}