Yep. AI rewrote the whole thing.

Downterm/CommandNotch/Models/WorkspaceRegistry.swift

@@ -0,0 +1,150 @@
+import SwiftUI
+
+@MainActor
+final class WorkspaceRegistry: ObservableObject {
+    static let shared = WorkspaceRegistry(store: UserDefaultsWorkspaceStore())
+
+    @Published private(set) var workspaceSummaries: [WorkspaceSummary]
+
+    private let store: any WorkspaceStoreType
+    private var controllers: [WorkspaceID: WorkspaceController] = [:]
+    private let controllerFactory: @MainActor (WorkspaceSummary) -> WorkspaceController
+
+    init(
+        initialWorkspaces: [WorkspaceSummary]? = nil,
+        store: (any WorkspaceStoreType)? = nil,
+        controllerFactory: @escaping @MainActor (WorkspaceSummary) -> WorkspaceController = { summary in
+            WorkspaceController(summary: summary)
+        }
+    ) {
+        let resolvedStore = store ?? UserDefaultsWorkspaceStore()
+        let resolvedWorkspaces = initialWorkspaces ?? resolvedStore.loadWorkspaceSummaries()
+
+        self.store = resolvedStore
+        self.controllerFactory = controllerFactory
+        self.workspaceSummaries = resolvedWorkspaces
+
+        for summary in resolvedWorkspaces {
+            controllers[summary.id] = controllerFactory(summary)
+        }
+
+        _ = ensureWorkspaceExists()
+    }
+
+    var defaultWorkspaceID: WorkspaceID {
+        ensureWorkspaceExists()
+    }
+
+    var defaultWorkspaceController: WorkspaceController {
+        let workspaceID = ensureWorkspaceExists()
+        guard let controller = controllers[workspaceID] else {
+            let summary = WorkspaceSummary(id: workspaceID, name: "Main")
+            let controller = controllerFactory(summary)
+            controllers[workspaceID] = controller
+            return controller
+        }
+        return controller
+    }
+
+    func allWorkspaceSummaries() -> [WorkspaceSummary] {
+        workspaceSummaries
+    }
+
+    func summary(for id: WorkspaceID) -> WorkspaceSummary? {
+        workspaceSummaries.first { $0.id == id }
+    }
+
+    func controller(for id: WorkspaceID) -> WorkspaceController? {
+        controllers[id]
+    }
+
+    func canDeleteWorkspace(id: WorkspaceID) -> Bool {
+        workspaceSummaries.count > 1 && workspaceSummaries.contains { $0.id == id }
+    }
+
+    func deletionFallbackWorkspaceID(
+        forDeleting id: WorkspaceID,
+        preferredFallback preferredFallbackID: WorkspaceID? = nil
+    ) -> WorkspaceID? {
+        let candidates = workspaceSummaries.filter { $0.id != id }
+
+        if let preferredFallbackID,
+           candidates.contains(where: { $0.id == preferredFallbackID }) {
+            return preferredFallbackID
+        }
+
+        return candidates.first?.id
+    }
+
+    @discardableResult
+    func ensureWorkspaceExists() -> WorkspaceID {
+        if let existing = workspaceSummaries.first {
+            return existing.id
+        }
+        return createWorkspace(named: "Main")
+    }
+
+    @discardableResult
+    func createWorkspace(named name: String? = nil) -> WorkspaceID {
+        let workspaceName = resolvedWorkspaceName(from: name)
+        let summary = WorkspaceSummary(name: workspaceName)
+        workspaceSummaries.append(summary)
+        controllers[summary.id] = controllerFactory(summary)
+        persistWorkspaceSummaries()
+        return summary.id
+    }
+
+    func renameWorkspace(id: WorkspaceID, to name: String) {
+        let trimmed = name.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !trimmed.isEmpty else { return }
+        guard let index = workspaceSummaries.firstIndex(where: { $0.id == id }) else { return }
+
+        workspaceSummaries[index].name = trimmed
+        controllers[id]?.rename(to: trimmed)
+        persistWorkspaceSummaries()
+    }
+
+    @discardableResult
+    func deleteWorkspace(id: WorkspaceID) -> Bool {
+        guard canDeleteWorkspace(id: id) else { return false }
+        workspaceSummaries.removeAll { $0.id == id }
+        controllers.removeValue(forKey: id)
+        _ = ensureWorkspaceExists()
+        persistWorkspaceSummaries()
+        return true
+    }
+
+    func updateAllWorkspacesFontSizes(_ size: CGFloat) {
+        for controller in controllers.values {
+            controller.updateAllFontSizes(size)
+        }
+    }
+
+    func updateAllWorkspacesThemes(_ theme: TerminalTheme) {
+        for controller in controllers.values {
+            controller.updateAllThemes(theme)
+        }
+    }
+
+    private func resolvedWorkspaceName(from proposedName: String?) -> String {
+        let trimmed = proposedName?.trimmingCharacters(in: .whitespacesAndNewlines) ?? ""
+        if !trimmed.isEmpty {
+            return trimmed
+        }
+
+        let existing = Set(workspaceSummaries.map(\.name))
+        if !existing.contains("Main") {
+            return "Main"
+        }
+
+        var index = 2
+        while existing.contains("Workspace \(index)") {
+            index += 1
+        }
+        return "Workspace \(index)"
+    }
+
+    private func persistWorkspaceSummaries() {
+        store.saveWorkspaceSummaries(workspaceSummaries)
+    }
+}