Implement drag and drop feed arrangement.

NetNewsWire.xcodeproj/project.pbxproj

@@ -90,6 +90,9 @@
 		515D4FC123257A3200EE1167 /* FolderTreeControllerDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 849A97A11ED9F180007D329B /* FolderTreeControllerDelegate.swift */; };
 		515D4FCA23257CB500EE1167 /* Node-Extensions.swift in Sources */ = {isa = PBXBuildFile; fileRef = 849A97971ED9EFAA007D329B /* Node-Extensions.swift */; };
 		515D4FCC2325815A00EE1167 /* SafariExt.js in Resources */ = {isa = PBXBuildFile; fileRef = 515D4FCB2325815A00EE1167 /* SafariExt.js */; };
+		51627A6723861DA3007B3B4B /* MasterFeedViewController+Drag.swift in Sources */ = {isa = PBXBuildFile; fileRef = 51627A6623861DA3007B3B4B /* MasterFeedViewController+Drag.swift */; };
+		51627A6923861DED007B3B4B /* MasterFeedViewController+Drop.swift in Sources */ = {isa = PBXBuildFile; fileRef = 51627A6823861DED007B3B4B /* MasterFeedViewController+Drop.swift */; };
+		51627A6B238629D8007B3B4B /* MasterFeedDataSource.swift in Sources */ = {isa = PBXBuildFile; fileRef = 51627A6A238629D8007B3B4B /* MasterFeedDataSource.swift */; };
 		516A093723609A3600EAE89B /* SettingsAccountTableViewCell.xib in Resources */ = {isa = PBXBuildFile; fileRef = 516A091D23609A3600EAE89B /* SettingsAccountTableViewCell.xib */; };
 		516A09392360A2AE00EAE89B /* SettingsAccountTableViewCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = 516A09382360A2AE00EAE89B /* SettingsAccountTableViewCell.swift */; };
 		516A093B2360A4A000EAE89B /* SettingsTableViewCell.xib in Resources */ = {isa = PBXBuildFile; fileRef = 516A093A2360A4A000EAE89B /* SettingsTableViewCell.xib */; };
@@ -212,7 +215,6 @@
 		51C452AF2265108300C03939 /* ArticleArray.swift in Sources */ = {isa = PBXBuildFile; fileRef = 84F204DF1FAACBB30076E152 /* ArticleArray.swift */; };
 		51C452B42265141B00C03939 /* WebKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 51C452B32265141B00C03939 /* WebKit.framework */; };
 		51C452B82265178500C03939 /* styleSheet.css in Resources */ = {isa = PBXBuildFile; fileRef = 51C452B72265178500C03939 /* styleSheet.css */; };
-		51CC9B3E231720B2000E842F /* MasterFeedDataSource.swift in Sources */ = {isa = PBXBuildFile; fileRef = 51CC9B3D231720B2000E842F /* MasterFeedDataSource.swift */; };
 		51CE1C0923621EDA005548FC /* RefreshProgressView.xib in Resources */ = {isa = PBXBuildFile; fileRef = 51CE1C0823621EDA005548FC /* RefreshProgressView.xib */; };
 		51CE1C0B23622007005548FC /* RefreshProgressView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 51CE1C0A23622006005548FC /* RefreshProgressView.swift */; };
 		51CE1C712367721A005548FC /* testURLsOfCurrentArticle.applescript in Sources */ = {isa = PBXBuildFile; fileRef = 84F9EADB213660A100CF2DE4 /* testURLsOfCurrentArticle.applescript */; };
@@ -1266,6 +1268,9 @@
 		515D4FCB2325815A00EE1167 /* SafariExt.js */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.javascript; path = SafariExt.js; sourceTree = "<group>"; };
 		515D4FCD2325909200EE1167 /* NetNewsWire_iOS_ShareExtension.entitlements */ = {isa = PBXFileReference; lastKnownFileType = text.plist.entitlements; path = NetNewsWire_iOS_ShareExtension.entitlements; sourceTree = "<group>"; };
 		515D4FCE2325B3D000EE1167 /* NetNewsWire_iOSshareextension_target.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; path = NetNewsWire_iOSshareextension_target.xcconfig; sourceTree = "<group>"; };
+		51627A6623861DA3007B3B4B /* MasterFeedViewController+Drag.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "MasterFeedViewController+Drag.swift"; sourceTree = "<group>"; };
+		51627A6823861DED007B3B4B /* MasterFeedViewController+Drop.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "MasterFeedViewController+Drop.swift"; sourceTree = "<group>"; };
+		51627A6A238629D8007B3B4B /* MasterFeedDataSource.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = MasterFeedDataSource.swift; sourceTree = "<group>"; };
 		516A091D23609A3600EAE89B /* SettingsAccountTableViewCell.xib */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = file.xib; path = SettingsAccountTableViewCell.xib; sourceTree = "<group>"; };
 		516A09382360A2AE00EAE89B /* SettingsAccountTableViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SettingsAccountTableViewCell.swift; sourceTree = "<group>"; };
 		516A093A2360A4A000EAE89B /* SettingsTableViewCell.xib */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = file.xib; path = SettingsTableViewCell.xib; sourceTree = "<group>"; };
@@ -1326,7 +1331,6 @@
 		51C4528B2265095F00C03939 /* AddFolderViewController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = AddFolderViewController.swift; sourceTree = "<group>"; };
 		51C452B32265141B00C03939 /* WebKit.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = WebKit.framework; path = Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS12.2.sdk/System/Library/Frameworks/WebKit.framework; sourceTree = DEVELOPER_DIR; };
 		51C452B72265178500C03939 /* styleSheet.css */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.css; path = styleSheet.css; sourceTree = "<group>"; };
-		51CC9B3D231720B2000E842F /* MasterFeedDataSource.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MasterFeedDataSource.swift; sourceTree = "<group>"; };
 		51CE1C0823621EDA005548FC /* RefreshProgressView.xib */ = {isa = PBXFileReference; lastKnownFileType = file.xib; path = RefreshProgressView.xib; sourceTree = "<group>"; };
 		51CE1C0A23622006005548FC /* RefreshProgressView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RefreshProgressView.swift; sourceTree = "<group>"; };
 		51D6A5BB23199C85001C27D8 /* MasterTimelineDataSource.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MasterTimelineDataSource.swift; sourceTree = "<group>"; };
@@ -1875,7 +1879,9 @@
 			isa = PBXGroup;
 			children = (
 				51C45264226508F600C03939 /* MasterFeedViewController.swift */,
-				51CC9B3D231720B2000E842F /* MasterFeedDataSource.swift */,
+				51627A6A238629D8007B3B4B /* MasterFeedDataSource.swift */,
+				51627A6623861DA3007B3B4B /* MasterFeedViewController+Drag.swift */,
+				51627A6823861DED007B3B4B /* MasterFeedViewController+Drop.swift */,
 				51CE1C0A23622006005548FC /* RefreshProgressView.swift */,
 				51CE1C0823621EDA005548FC /* RefreshProgressView.xib */,
 				51C45260226508F600C03939 /* Cell */,
@@ -3976,6 +3982,7 @@
 				51F85BF722749FA100C787DC /* UIFont-Extensions.swift in Sources */,
 				51C452AF2265108300C03939 /* ArticleArray.swift in Sources */,
 				51C4528E2265099C00C03939 /* SmartFeedsController.swift in Sources */,
+				51627A6B238629D8007B3B4B /* MasterFeedDataSource.swift in Sources */,
 				51102165233A7D6C0007A5F7 /* ArticleExtractorButton.swift in Sources */,
 				5141E7392373C18B0013FF27 /* WebFeedInspectorViewController.swift in Sources */,
 				5108F6D42375EEEF001ABC45 /* TimelinePreviewTableViewController.swift in Sources */,
@@ -4001,6 +4008,7 @@
 				51934CCE2310792F006127BE /* ActivityManager.swift in Sources */,
 				5108F6B72375E612001ABC45 /* CacheCleaner.swift in Sources */,
 				518651DA235621840078E021 /* ImageTransition.swift in Sources */,
+				51627A6923861DED007B3B4B /* MasterFeedViewController+Drop.swift in Sources */,
 				514219372352510100E07E2C /* ImageScrollView.swift in Sources */,
 				516AE9B32371C372007DEEAA /* MasterFeedTableViewSectionHeaderLayout.swift in Sources */,
 				51C4529B22650A1000C03939 /* FaviconDownloader.swift in Sources */,
@@ -4012,12 +4020,12 @@
 				51C4529F22650A1900C03939 /* AuthorAvatarDownloader.swift in Sources */,
 				5108F6D22375EED2001ABC45 /* TimelineCustomizerViewController.swift in Sources */,
 				519E743D22C663F900A78E47 /* SceneDelegate.swift in Sources */,
-				51CC9B3E231720B2000E842F /* MasterFeedDataSource.swift in Sources */,
 				FFD43E412340F488009E5CA3 /* UndoAvailableAlertController.swift in Sources */,
 				51C452A322650A1E00C03939 /* HTMLMetadataDownloader.swift in Sources */,
 				51C4528D2265095F00C03939 /* AddFolderViewController.swift in Sources */,
 				51C452782265091600C03939 /* MasterTimelineCellData.swift in Sources */,
 				5148F4552336DB7000F8CD8B /* MasterTimelineTitleView.swift in Sources */,
+				51627A6723861DA3007B3B4B /* MasterFeedViewController+Drag.swift in Sources */,
 				51FFF0C4235EE8E5002762AA /* VibrantButton.swift in Sources */,
 				513228FC233037630033D4ED /* Reachability.swift in Sources */,
 				51C45259226508D300C03939 /* AppDefaults.swift in Sources */,

iOS/MasterFeed/MasterFeedDataSource.swift

@@ -14,12 +14,10 @@ import Account
 class MasterFeedDataSource: UITableViewDiffableDataSource<Node, Node> {
 
 	private var coordinator: SceneCoordinator!
-	private var errorHandler: ((Error) -> ())!
 	
-	init(coordinator: SceneCoordinator, errorHandler: @escaping (Error) -> (), tableView: UITableView, cellProvider: @escaping UITableViewDiffableDataSource<Node, Node>.CellProvider) {
+	init(coordinator: SceneCoordinator, tableView: UITableView, cellProvider: @escaping UITableViewDiffableDataSource<Node, Node>.CellProvider) {
 		super.init(tableView: tableView, cellProvider: cellProvider)
 		self.coordinator = coordinator
-		self.errorHandler = errorHandler
 		self.defaultRowAnimation = .middle
 	}
 	
@@ -30,140 +28,4 @@ class MasterFeedDataSource: UITableViewDiffableDataSource<Node, Node> {
 		return true
 	}
 	
-	override func tableView(_ tableView: UITableView, canMoveRowAt indexPath: IndexPath) -> Bool {
-		guard let node = itemIdentifier(for: indexPath) else {
-			return false
-		}
-		return node.representedObject is WebFeed
-	}
-	
-	override func tableView(_ tableView: UITableView, moveRowAt sourceIndexPath: IndexPath, to destinationIndexPath: IndexPath) {
-
-		guard let sourceNode = itemIdentifier(for: sourceIndexPath), let webFeed = sourceNode.representedObject as? WebFeed else {
-			return
-		}
-
-		// Based on the drop we have to determine a node to start looking for a parent container.
-		let destNode: Node = {
-			if destinationIndexPath.row == 0 {
-				return coordinator.rootNode.childAtIndex(destinationIndexPath.section)!
-			} else {
-				let movementAdjustment = sourceIndexPath > destinationIndexPath ? 1 : 0
-				let adjustedDestIndexPath = IndexPath(row: destinationIndexPath.row - movementAdjustment, section: destinationIndexPath.section)
-				return itemIdentifier(for: adjustedDestIndexPath)!
-			}
-		}()
-
-		// Now we start looking for the parent container
-		let destParentNode: Node? = {
-			if destNode.representedObject is Container {
-				return destNode
-			} else {
-				if destNode.parent?.representedObject is Container {
-					return destNode.parent!
-				} else {
-					return nil
-				}
-			}
-		}()
-		
-		// Move the Web Feed
-		guard let source = sourceNode.parent?.representedObject as? Container, let destination = destParentNode?.representedObject as? Container else {
-			return
-		}
-		
-		if sameAccount(sourceNode, destParentNode!) {
-			moveWebFeedInAccount(feed: webFeed, sourceContainer: source, destinationContainer: destination)
-		} else {
-			moveWebFeedBetweenAccounts(feed: webFeed, sourceContainer: source, destinationContainer: destination)
-		}
-
-	}
-	
-	private func sameAccount(_ node: Node, _ parentNode: Node) -> Bool {
-		if let accountID = nodeAccountID(node), let parentAccountID = nodeAccountID(parentNode) {
-			if accountID == parentAccountID {
-				return true
-			}
-		}
-		return false
-	}
-	
-	private func nodeAccount(_ node: Node) -> Account? {
-		if let account = node.representedObject as? Account {
-			return account
-		} else if let folder = node.representedObject as? Folder {
-			return folder.account
-		} else if let webFeed = node.representedObject as? WebFeed {
-			return webFeed.account
-		} else {
-			return nil
-		}
-
-	}
-
-	private func nodeAccountID(_ node: Node) -> String? {
-		return nodeAccount(node)?.accountID
-	}
-
-	func moveWebFeedInAccount(feed: WebFeed, sourceContainer: Container, destinationContainer: Container) {
-		BatchUpdate.shared.start()
-		sourceContainer.account?.moveWebFeed(feed, from: sourceContainer, to: destinationContainer) { result in
-			BatchUpdate.shared.end()
-			switch result {
-			case .success:
-				break
-			case .failure(let error):
-				self.errorHandler(error)
-			}
-		}
-	}
-	
-	func moveWebFeedBetweenAccounts(feed: WebFeed, sourceContainer: Container, destinationContainer: Container) {
-		
-		if let existingFeed = destinationContainer.account?.existingWebFeed(withURL: feed.url) {
-			
-			BatchUpdate.shared.start()
-			destinationContainer.account?.addWebFeed(existingFeed, to: destinationContainer) { result in
-				switch result {
-				case .success:
-					sourceContainer.account?.removeWebFeed(feed, from: sourceContainer) { result in
-						BatchUpdate.shared.end()
-						switch result {
-						case .success:
-							break
-						case .failure(let error):
-							self.errorHandler(error)
-						}
-					}
-				case .failure(let error):
-					BatchUpdate.shared.end()
-					self.errorHandler(error)
-				}
-			}
-			
-		} else {
-			
-			BatchUpdate.shared.start()
-			destinationContainer.account?.createWebFeed(url: feed.url, name: feed.editedName, container: destinationContainer) { result in
-				switch result {
-				case .success:
-					sourceContainer.account?.removeWebFeed(feed, from: sourceContainer) { result in
-						BatchUpdate.shared.end()
-						switch result {
-						case .success:
-							break
-						case .failure(let error):
-							self.errorHandler(error)
-						}
-					}
-				case .failure(let error):
-					BatchUpdate.shared.end()
-					self.errorHandler(error)
-				}
-			}
-			
-		}
-	}
-
 }

iOS/MasterFeed/MasterFeedViewController+Drag.swift

@@ -0,0 +1,33 @@
+//
+//  MasterFeedViewController+Drag.swift
+//  NetNewsWire-iOS
+//
+//  Created by Maurice Parker on 11/20/19.
+//  Copyright © 2019 Ranchero Software. All rights reserved.
+//
+
+import UIKit
+import MobileCoreServices
+import Account
+
+extension MasterFeedViewController: UITableViewDragDelegate {
+	
+	func tableView(_ tableView: UITableView, itemsForBeginning session: UIDragSession, at indexPath: IndexPath) -> [UIDragItem] {
+		guard let node = dataSource.itemIdentifier(for: indexPath), let webFeed = node.representedObject as? WebFeed else {
+			return [UIDragItem]()
+		}
+		
+		let data = webFeed.url.data(using: .utf8)
+		let itemProvider = NSItemProvider()
+		  
+		itemProvider.registerDataRepresentation(forTypeIdentifier: kUTTypeURL as String, visibility: .all) { completion in
+			completion(data, nil)
+			return nil
+		}
+		
+		let dragItem = UIDragItem(itemProvider: itemProvider)
+		dragItem.localObject = node
+		return [dragItem]
+	}
+	
+}

iOS/MasterFeed/MasterFeedViewController.swift

@@ -17,7 +17,7 @@ class MasterFeedViewController: UITableViewController, UndoableCommandRunner {
 	private var refreshProgressView: RefreshProgressView?
 	private var addNewItemButton: UIBarButtonItem!
 	
-	private lazy var dataSource = makeDataSource()
+	lazy var dataSource = makeDataSource()
 	var undoableCommands = [UndoableCommand]()
 	weak var coordinator: SceneCoordinator!
 	
@@ -38,8 +38,6 @@ class MasterFeedViewController: UITableViewController, UndoableCommandRunner {
 			navigationController?.navigationBar.prefersLargeTitles = true
 		}
 		
-		navigationItem.rightBarButtonItem = editButtonItem
-
 		// Set the bar button item so that it doesn't show on the timeline view
 		navigationItem.backBarButtonItem = UIBarButtonItem(title: "", style: .plain, target: nil, action: nil)
 
@@ -51,6 +49,9 @@ class MasterFeedViewController: UITableViewController, UndoableCommandRunner {
 		
 		tableView.register(MasterFeedTableViewSectionHeader.self, forHeaderFooterViewReuseIdentifier: "SectionHeader")
 		tableView.dataSource = dataSource
+		tableView.dragDelegate = self
+		tableView.dropDelegate = self
+		tableView.dragInteractionEnabled = true
 		resetEstimatedRowHeight()
 		tableView.separatorStyle = .none
 
@@ -630,7 +631,7 @@ private extension MasterFeedViewController {
 	}
 
     func makeDataSource() -> UITableViewDiffableDataSource<Node, Node> {
-		return MasterFeedDataSource(coordinator: coordinator, errorHandler: ErrorHandler.present(self), tableView: tableView, cellProvider: { [weak self] tableView, indexPath, node in
+		return MasterFeedDataSource(coordinator: coordinator, tableView: tableView, cellProvider: { [weak self] tableView, indexPath, node in
 			let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! MasterFeedTableViewCell
 			self?.configure(cell, node)
 			return cell