1 files changed, 103 insertions, 0 deletions
diff --git a/macos/Sources/Features/Update/UpdateDriver.swift b/macos/Sources/Features/Update/UpdateDriver.swift
new file mode 100644
index 000000000..00f74e9ed
--- /dev/null
+++ b/macos/Sources/Features/Update/UpdateDriver.swift
@@ -0,0 +1,103 @@
+import Sparkle
+
+/// Implement the SPUUserDriver to modify our UpdateViewModel for custom presentation.
+class UpdateDriver: NSObject, SPUUserDriver {
+    let viewModel: UpdateViewModel
+    let retryHandler: () -> Void
+    
+    init(viewModel: UpdateViewModel, retryHandler: @escaping () -> Void) {
+        self.viewModel = viewModel
+        self.retryHandler = retryHandler
+        super.init()
+    }
+    
+    func show(_ request: SPUUpdatePermissionRequest, reply: @escaping @Sendable (SUUpdatePermissionResponse) -> Void) {
+        viewModel.state = .permissionRequest(.init(request: request, reply: reply))
+    }
+    
+    func showUserInitiatedUpdateCheck(cancellation: @escaping () -> Void) {
+        viewModel.state = .checking(.init(cancel: cancellation))
+    }
+    
+    func showUpdateFound(with appcastItem: SUAppcastItem, state: SPUUserUpdateState, reply: @escaping @Sendable (SPUUserUpdateChoice) -> Void) {
+        viewModel.state = .updateAvailable(.init(appcastItem: appcastItem, reply: reply))
+    }
+    
+    func showUpdateReleaseNotes(with downloadData: SPUDownloadData) {
+        // We don't do anything with the release notes here because Ghostty
+        // doesn't use the release notes feature of Sparkle currently.
+    }
+    
+    func showUpdateReleaseNotesFailedToDownloadWithError(_ error: any Error) {
+        // We don't do anything with release notes. See `showUpdateReleaseNotes`
+    }
+    
+    func showUpdateNotFoundWithError(_ error: any Error, acknowledgement: @escaping () -> Void) {
+        viewModel.state = .notFound
+        // TODO: Do we need to acknowledge?
+    }
+    
+    func showUpdaterError(_ error: any Error, acknowledgement: @escaping () -> Void) {
+        viewModel.state = .error(.init(error: error, retry: retryHandler))
+    }
+    
+    func showDownloadInitiated(cancellation: @escaping () -> Void) {
+        viewModel.state = .downloading(.init(
+            cancel: cancellation,
+            expectedLength: nil,
+            progress: 0))
+    }
+    
+    func showDownloadDidReceiveExpectedContentLength(_ expectedContentLength: UInt64) {
+        guard case let .downloading(downloading) = viewModel.state else {
+            return
+        }
+            
+        viewModel.state = .downloading(.init(
+            cancel: downloading.cancel,
+            expectedLength: expectedContentLength,
+            progress: 0))
+    }
+    
+    func showDownloadDidReceiveData(ofLength length: UInt64) {
+        guard case let .downloading(downloading) = viewModel.state else {
+            return
+        }
+        
+        viewModel.state = .downloading(.init(
+            cancel: downloading.cancel,
+            expectedLength: downloading.expectedLength,
+            progress: downloading.progress + length))
+    }
+    
+    func showDownloadDidStartExtractingUpdate() {
+        viewModel.state = .extracting(.init(progress: 0))
+    }
+    
+    func showExtractionReceivedProgress(_ progress: Double) {
+        viewModel.state = .extracting(.init(progress: progress))
+    }
+    
+    func showReady(toInstallAndRelaunch reply: @escaping @Sendable (SPUUserUpdateChoice) -> Void) {
+        viewModel.state = .readyToInstall(.init(reply: reply))
+    }
+    
+    func showInstallingUpdate(withApplicationTerminated applicationTerminated: Bool, retryTerminatingApplication: @escaping () -> Void) {
+        viewModel.state = .installing
+    }
+    
+    func showUpdateInstalledAndRelaunched(_ relaunched: Bool, acknowledgement: @escaping () -> Void) {
+        // We don't do anything here.
+        viewModel.state = .idle
+    }
+    
+    func showUpdateInFocus() {
+        // We don't currently implement this because our update state is
+        // shown in a terminal window. We may want to implement this at some
+        // point to handle the case that no windows are open, though.
+    }
+    
+    func dismissUpdateInstallation() {
+        viewModel.state = .idle
+    }
+}