Cestino: ripristino e svuota cestino nel servizio (#22)

CalenTask/Services/TrashService.swift

@@ -27,4 +27,35 @@ enum TrashService {
         context.saveOrLog()
         return purgeable.count
     }
+
+    /// Attività nel cestino (radici dei sottoalberi eliminati), le più recenti prima.
+    @MainActor
+    static func trashedRoots(in context: ModelContext) -> [TodoTask] {
+        let predicate = #Predicate<TodoTask> { $0.deletedAt != nil }
+        return context.fetchOrLog(FetchDescriptor<TodoTask>(predicate: predicate))
+            .filter { $0.parentTask?.deletedAt == nil }
+            .sorted { ($0.deletedAt ?? .distantPast) > ($1.deletedAt ?? .distantPast) }
+    }
+
+    /// Ripristina una task e tutto il suo sottoalbero eliminato.
+    @MainActor
+    static func restore(_ task: TodoTask) {
+        for child in task.subtasks where child.deletedAt != nil {
+            restore(child)
+        }
+        guard task.deletedAt != nil else { return }
+        task.deletedAt = nil
+        task.touch()
+    }
+
+    /// Elimina definitivamente tutto il cestino. Ritorna quante task ha rimosso.
+    @MainActor
+    @discardableResult
+    static func emptyTrash(in context: ModelContext) -> Int {
+        let predicate = #Predicate<TodoTask> { $0.deletedAt != nil }
+        let all = context.fetchOrLog(FetchDescriptor<TodoTask>(predicate: predicate))
+        all.forEach { context.delete($0) }
+        context.saveOrLog()
+        return all.count
+    }
 }

CalenTaskTests/TrashServiceTests.swift

@@ -35,4 +35,30 @@ struct TrashServiceTests {
         let titles = try context.fetch(FetchDescriptor<TodoTask>()).map(\.title).sorted()
         #expect(titles == ["Recente", "Viva"])
     }
+
+    @Test func restoreBringsBackSubtree() throws {
+        let context = try makeContext()
+        let author = UUID(), ws = UUID()
+        let parent = TodoTask(workspaceID: ws, title: "Padre", createdByID: author)
+        let child = TodoTask(workspaceID: ws, title: "Figlio", createdByID: author)
+        context.insert(parent); context.insert(child)
+        child.parentTask = parent
+        parent.softDeleteSubtree()
+        #expect(TrashService.trashedRoots(in: context).map(\.title) == ["Padre"])
+
+        TrashService.restore(parent)
+        #expect(parent.deletedAt == nil && child.deletedAt == nil)
+        #expect(TrashService.trashedRoots(in: context).isEmpty)
+    }
+
+    @Test func emptyTrashRemovesOnlyDeleted() throws {
+        let context = try makeContext()
+        let author = UUID(), ws = UUID()
+        let gone = TodoTask(workspaceID: ws, title: "Via", createdByID: author)
+        let live = TodoTask(workspaceID: ws, title: "Viva", createdByID: author)
+        context.insert(gone); context.insert(live)
+        gone.deletedAt = .now
+        #expect(TrashService.emptyTrash(in: context) == 1)
+        #expect(try context.fetch(FetchDescriptor<TodoTask>()).map(\.title) == ["Viva"])
+    }
 }