feat(ios): extend swipe actions to milestones

ios/Sources/ContentScreens.swift

@@ -19,14 +19,109 @@ private extension UIViewController {
 }
 
 @MainActor
-final class IssuesViewController: RefreshingTableViewController {
-    private let context: AppContext
-    private let owner: String
-    private let repository: String
+private protocol IssueSwipeActionHost: AnyObject {
+    var context: AppContext { get }
+    var owner: String { get }
+    var repository: String { get }
+    var issueMutationTask: Task<Void, Never>? { get set }
+    func reloadIssuesAfterMutation()
+}
+
+private extension IssueSwipeActionHost where Self: UIViewController {
+    func issueSwipeActions(for row: IssueRow) -> UISwipeActionsConfiguration {
+        let close = row.state != "closed"
+        let stateAction = UIContextualAction(
+            style: .normal,
+            title: close ? "Close" : "Open"
+        ) { [weak self] _, _, completion in
+            self?.setIssue(row, closed: close, completion: completion) ?? completion(false)
+        }
+        stateAction.image = context.symbol(close ? "checkmark.circle" : "arrow.uturn.left.circle")
+        stateAction.backgroundColor = close ? .systemPurple : .systemGreen
+
+        let deleteAction = UIContextualAction(style: .destructive, title: "Delete") {
+            [weak self] _, _, completion in
+            self?.confirmDeleteIssue(row, completion: completion) ?? completion(false)
+        }
+        deleteAction.image = context.symbol("trash")
+
+        let configuration = UISwipeActionsConfiguration(actions: [stateAction, deleteAction])
+        configuration.performsFirstActionWithFullSwipe = true
+        return configuration
+    }
+
+    private func setIssue(
+        _ row: IssueRow,
+        closed: Bool,
+        completion: @escaping (Bool) -> Void
+    ) {
+        issueMutationTask?.cancel()
+        issueMutationTask = Task {
+            do {
+                try await context.core.setIssueClosed(
+                    owner: owner,
+                    repository: repository,
+                    number: row.number,
+                    closed: closed
+                )
+                guard !Task.isCancelled else {
+                    completion(false)
+                    return
+                }
+                completion(true)
+                reloadIssuesAfterMutation()
+            } catch {
+                completion(false)
+                if !Task.isCancelled { show(error: error) }
+            }
+        }
+    }
+
+    private func confirmDeleteIssue(_ row: IssueRow, completion: @escaping (Bool) -> Void) {
+        let alert = UIAlertController(
+            title: "Delete Issue #\(row.number)?",
+            message: "“\(row.title)” will be permanently deleted. This can’t be undone.",
+            preferredStyle: .alert
+        )
+        alert.addAction(UIAlertAction(title: "Cancel", style: .cancel) { _ in completion(false) })
+        alert.addAction(UIAlertAction(title: "Delete", style: .destructive) { [weak self] _ in
+            guard let self else {
+                completion(false)
+                return
+            }
+            self.issueMutationTask?.cancel()
+            self.issueMutationTask = Task {
+                do {
+                    try await self.context.core.deleteIssue(
+                        owner: self.owner,
+                        repository: self.repository,
+                        number: row.number
+                    )
+                    guard !Task.isCancelled else {
+                        completion(false)
+                        return
+                    }
+                    completion(true)
+                    self.reloadIssuesAfterMutation()
+                } catch {
+                    completion(false)
+                    if !Task.isCancelled { self.show(error: error) }
+                }
+            }
+        })
+        present(alert, animated: true)
+    }
+}
+
+@MainActor
+final class IssuesViewController: RefreshingTableViewController, IssueSwipeActionHost {
+    fileprivate let context: AppContext
+    fileprivate let owner: String
+    fileprivate let repository: String
     private var rows: [IssueRow] = []
     private var filterOptions: IssueFilterOptions?
     private var filterTask: Task<Void, Never>?
-    private var mutationTask: Task<Void, Never>?
+    fileprivate var issueMutationTask: Task<Void, Never>?
     private var currentPage: UInt32 = 0
     private lazy var filterButton = UIBarButtonItem(
         image: context.symbol("line.3.horizontal.decrease.circle")
@@ -45,7 +140,7 @@ final class IssuesViewController: RefreshingTableViewController {
 
     deinit {
         filterTask?.cancel()
-        mutationTask?.cancel()
+        issueMutationTask?.cancel()
     }
 
     override func viewDidLoad() {
@@ -151,88 +246,11 @@ final class IssuesViewController: RefreshingTableViewController {
         _ tableView: UITableView,
         trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath
     ) -> UISwipeActionsConfiguration? {
-        let row = rows[indexPath.row]
-        let close = row.state != "closed"
-        let stateAction = UIContextualAction(
-            style: .normal,
-            title: close ? "Close" : "Open"
-        ) { [weak self] _, _, completion in
-            self?.setIssue(row, closed: close, completion: completion) ?? completion(false)
-        }
-        stateAction.image = context.symbol(close ? "checkmark.circle" : "arrow.uturn.left.circle")
-        stateAction.backgroundColor = close ? .systemPurple : .systemGreen
-
-        let deleteAction = UIContextualAction(style: .destructive, title: "Delete") {
-            [weak self] _, _, completion in
-            self?.confirmDelete(row, completion: completion) ?? completion(false)
-        }
-        deleteAction.image = context.symbol("trash")
-
-        let configuration = UISwipeActionsConfiguration(actions: [stateAction, deleteAction])
-        configuration.performsFirstActionWithFullSwipe = true
-        return configuration
+        issueSwipeActions(for: rows[indexPath.row])
     }
 
-    private func setIssue(
-        _ row: IssueRow,
-        closed: Bool,
-        completion: @escaping (Bool) -> Void
-    ) {
-        mutationTask?.cancel()
-        mutationTask = Task {
-            do {
-                try await context.core.setIssueClosed(
-                    owner: owner,
-                    repository: repository,
-                    number: row.number,
-                    closed: closed
-                )
-                guard !Task.isCancelled else {
-                    completion(false)
-                    return
-                }
-                completion(true)
-                loadIssues(refreshing: false)
-            } catch {
-                completion(false)
-                if !Task.isCancelled { show(error: error) }
-            }
-        }
-    }
-
-    private func confirmDelete(_ row: IssueRow, completion: @escaping (Bool) -> Void) {
-        let alert = UIAlertController(
-            title: "Delete Issue #\(row.number)?",
-            message: "“\(row.title)” will be permanently deleted. This can’t be undone.",
-            preferredStyle: .alert
-        )
-        alert.addAction(UIAlertAction(title: "Cancel", style: .cancel) { _ in completion(false) })
-        alert.addAction(UIAlertAction(title: "Delete", style: .destructive) { [weak self] _ in
-            guard let self else {
-                completion(false)
-                return
-            }
-            self.mutationTask?.cancel()
-            self.mutationTask = Task {
-                do {
-                    try await self.context.core.deleteIssue(
-                        owner: self.owner,
-                        repository: self.repository,
-                        number: row.number
-                    )
-                    guard !Task.isCancelled else {
-                        completion(false)
-                        return
-                    }
-                    completion(true)
-                    self.loadIssues(refreshing: false)
-                } catch {
-                    completion(false)
-                    if !Task.isCancelled { self.show(error: error) }
-                }
-            }
-        })
-        present(alert, animated: true)
+    fileprivate func reloadIssuesAfterMutation() {
+        loadIssues(refreshing: false)
     }
 
     private func updateFilterMenu() {
@@ -539,6 +557,7 @@ final class MilestonesViewController: RefreshingTableViewController {
     private let owner: String
     private let repository: String
     private var rows: [MilestoneRow] = []
+    private var mutationTask: Task<Void, Never>?
     private var currentPage: UInt32 = 0
 
     init(context: AppContext, owner: String, repository: String) {
@@ -552,6 +571,8 @@ final class MilestonesViewController: RefreshingTableViewController {
     @available(*, unavailable)
     required init?(coder: NSCoder) { fatalError("init(coder:) is not supported") }
 
+    deinit { mutationTask?.cancel() }
+
     override func viewDidLoad() {
         super.viewDidLoad()
         tableView.register(MilestoneCell.self, forCellReuseIdentifier: "milestone")
@@ -648,15 +669,114 @@ final class MilestonesViewController: RefreshingTableViewController {
             animated: true
         )
     }
+
+    override func tableView(
+        _ tableView: UITableView,
+        trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath
+    ) -> UISwipeActionsConfiguration? {
+        let row = rows[indexPath.row]
+        let close = row.state != "closed"
+        let stateAction = UIContextualAction(
+            style: .normal,
+            title: close ? "Close" : "Open"
+        ) { [weak self] _, _, completion in
+            self?.setMilestone(row, closed: close, completion: completion) ?? completion(false)
+        }
+        stateAction.image = context.symbol(close ? "checkmark.circle" : "arrow.uturn.left.circle")
+        stateAction.backgroundColor = close ? .systemPurple : .systemGreen
+
+        let deleteAction = UIContextualAction(style: .destructive, title: "Delete") {
+            [weak self] _, _, completion in
+            self?.confirmDelete(row, completion: completion) ?? completion(false)
+        }
+        deleteAction.image = context.symbol("trash")
+
+        let configuration = UISwipeActionsConfiguration(actions: [stateAction, deleteAction])
+        configuration.performsFirstActionWithFullSwipe = true
+        return configuration
+    }
+
+    private func setMilestone(
+        _ row: MilestoneRow,
+        closed: Bool,
+        completion: @escaping (Bool) -> Void
+    ) {
+        mutationTask?.cancel()
+        mutationTask = Task {
+            do {
+                try await context.core.setMilestoneClosed(
+                    owner: owner,
+                    repository: repository,
+                    id: row.id,
+                    closed: closed
+                )
+                guard !Task.isCancelled else {
+                    completion(false)
+                    return
+                }
+                completion(true)
+                loadContent(refreshing: false)
+            } catch {
+                completion(false)
+                if !Task.isCancelled { show(error: error) }
+            }
+        }
+    }
+
+    private func confirmDelete(_ row: MilestoneRow, completion: @escaping (Bool) -> Void) {
+        guard !row.hasIssues else {
+            let alert = UIAlertController(
+                title: "Milestone Can’t Be Deleted",
+                message: "Remove all assigned issues and pull requests first.",
+                preferredStyle: .alert
+            )
+            alert.addAction(UIAlertAction(title: "OK", style: .default) { _ in completion(false) })
+            present(alert, animated: true)
+            return
+        }
+        let alert = UIAlertController(
+            title: "Delete \(row.title)?",
+            message: "This milestone will be permanently deleted. This can’t be undone.",
+            preferredStyle: .alert
+        )
+        alert.addAction(UIAlertAction(title: "Cancel", style: .cancel) { _ in completion(false) })
+        alert.addAction(UIAlertAction(title: "Delete", style: .destructive) { [weak self] _ in
+            guard let self else {
+                completion(false)
+                return
+            }
+            self.mutationTask?.cancel()
+            self.mutationTask = Task {
+                do {
+                    try await self.context.core.deleteMilestone(
+                        owner: self.owner,
+                        repository: self.repository,
+                        id: row.id
+                    )
+                    guard !Task.isCancelled else {
+                        completion(false)
+                        return
+                    }
+                    completion(true)
+                    self.loadContent(refreshing: false)
+                } catch {
+                    completion(false)
+                    if !Task.isCancelled { self.show(error: error) }
+                }
+            }
+        })
+        present(alert, animated: true)
+    }
 }
 
 @MainActor
-final class MilestoneViewController: RefreshingTableViewController {
-    private let context: AppContext
-    private let owner: String
-    private let repository: String
+final class MilestoneViewController: RefreshingTableViewController, IssueSwipeActionHost {
+    fileprivate let context: AppContext
+    fileprivate let owner: String
+    fileprivate let repository: String
     private let id: Int64
     private var page: MilestonePage?
+    fileprivate var issueMutationTask: Task<Void, Never>?
     private var currentPage: UInt32 = 0
 
     init(context: AppContext, owner: String, repository: String, id: Int64) {
@@ -671,6 +791,8 @@ final class MilestoneViewController: RefreshingTableViewController {
     @available(*, unavailable)
     required init?(coder: NSCoder) { fatalError("init(coder:) is not supported") }
 
+    deinit { issueMutationTask?.cancel() }
+
     override func viewDidLoad() {
         super.viewDidLoad()
         tableView.register(MilestoneCell.self, forCellReuseIdentifier: "milestone")
@@ -820,6 +942,18 @@ final class MilestoneViewController: RefreshingTableViewController {
             )
         }
     }
+
+    override func tableView(
+        _ tableView: UITableView,
+        trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath
+    ) -> UISwipeActionsConfiguration? {
+        guard indexPath.section == 1, let issue = page?.issues[indexPath.row] else { return nil }
+        return issueSwipeActions(for: issue)
+    }
+
+    fileprivate func reloadIssuesAfterMutation() {
+        loadContent(refreshing: false)
+    }
 }
 
 final class MilestoneCell: UITableViewCell {