ET-638 Share extension

Modules/InboxComposer/Sources/Composer/Extensions/FileManager+AttachmentHelpers.swift

@@ -37,7 +37,7 @@ extension FileManager {
     /**
      Moves the given `file` to `destinationFolder`. If a file with the same name exists, it creates a unique file name using `uniqueFileNameURL(in folder:,baseName:,fileExtension:)`
      */
-    func moveToUniqueURL(file: URL, to destinationFolder: URL) throws -> URL {
+    public func moveToUniqueURL(file: URL, to destinationFolder: URL) throws -> URL {
         let uniqueURL = uniqueFileNameURL(
             in: destinationFolder,
             baseName: file.deletingPathExtension().lastPathComponent,

Modules/InboxComposer/Sources/Composer/UIKitComponents/Models/MockDraft.swift

@@ -178,7 +178,10 @@ final class MockDraft: AppDraftProtocol, @unchecked Sendable {
         mockSender
     }
 
-    func setBody(body: String) -> VoidDraftSaveResult { .ok }
+    func setBody(body: String) -> VoidDraftSaveResult {
+        mockBody = body
+        return .ok
+    }
 
     func setSubject(subject: String) -> VoidDraftSaveResult {
         mockSubject = subject

Modules/InboxComposer/Sources/Composer/Views/Attachments/Jpeg.swift

@@ -15,6 +15,6 @@
 // You should have received a copy of the GNU General Public License
 // along with Proton Mail. If not, see https://www.gnu.org/licenses/.
 
-enum JPEG {
-    static let compressionQuality = 0.8
+public enum JPEG {
+    public static let compressionQuality = 0.8
 }

Modules/InboxCore/Sources/AppLogger.swift

@@ -140,6 +140,7 @@ extension AppLogger {
         case rustLibrary
         case search
         case send
+        case shareExtension
         case snooze
         case thirtySecondsBackgroundTask
         case userSessions

Modules/InboxCore/Sources/ProtonMailUniffi/ApiEnvId+PaymentAvailability.swift

@@ -1,3 +1,4 @@
+//
 // Copyright (c) 2025 Proton Technologies AG
 //
 // This file is part of Proton Mail.
@@ -20,7 +21,7 @@ import proton_app_uniffi
 
 extension ApiEnvId {
     /// Payments are not available for sandbox users in production environment.
-    var arePaymentsEnabled: Bool {
+    public var arePaymentsEnabled: Bool {
         return !(isAppInstalledThroughTestFlight && self == .prod)
     }
 

Modules/InboxTesting/Sources/MailSessionSpy.swift

@@ -21,6 +21,8 @@ public final class MailSessionSpy: MailSessionProtocol {
     public var onPrimaryAccountChanged: (@Sendable (String) -> Void)?
     public var appProtectionStub: AppProtection = .none
 
+    public var primaryUserSessionStub: MailUserSession?
+
     public var storedSessions: [StoredSessionStub] = [] {
         didSet {
             Task {
@@ -242,7 +244,7 @@ public final class MailSessionSpy: MailSessionProtocol {
     }
 
     public func toPrimaryUserSession() async -> MailSessionToPrimaryUserSessionResult {
-        fatalError(#function)
+        .ok(primaryUserSessionStub!)
     }
 
     public func toUserSession(ffiFlow: LoginFlow) async -> MailSessionToUserSessionResult {

Modules/ShareExtension/Sources/ApiEnvId+Current.swift

@@ -0,0 +1,31 @@
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import Foundation
+import proton_app_uniffi
+
+extension ApiEnvId {
+    static let current: Self = {
+        #if QA || DEBUG
+            if let dynamicDomain = UserDefaults.appGroup.string(forKey: "DYNAMIC_DOMAIN") {
+                return .init(dynamicDomain: dynamicDomain)
+            }
+        #endif
+
+        return .prod
+    }()
+}

Modules/ShareExtension/Sources/ShareViewController.swift

@@ -0,0 +1,64 @@
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import Combine
+import InboxCore
+import InboxCoreUI
+import SwiftUI
+import TestableShareExtension
+
+final class ShareViewController: UINavigationController {
+    private var cancellables = Set<AnyCancellable>()
+
+    override func beginRequest(with context: NSExtensionContext) {
+        super.beginRequest(with: context)
+
+        let model = ShareScreenModel(apiEnvId: .current, extensionContext: context)
+        showMainScreen(basedOn: model)
+        setUpBindings(observing: model)
+    }
+
+    override func viewDidLoad() {
+        DynamicFontSize.capSupportedSizeCategories()
+
+        super.viewDidLoad()
+
+        isNavigationBarHidden = true
+    }
+
+    private func showMainScreen(basedOn model: ShareScreenModel) {
+        let screen = ShareScreen(model: model)
+        let hostingController = UIHostingController(rootView: screen)
+        setViewControllers([hostingController], animated: false)
+    }
+
+    private func setUpBindings(observing model: ShareScreenModel) {
+        model.$alert.sink { [weak self] message in
+            guard let self else { return }
+
+            if presentedViewController != nil {
+                dismiss(animated: true)
+            }
+
+            if let message {
+                let alert = UIAlertController(title: message, message: nil, preferredStyle: .alert)
+                present(alert, animated: true)
+            }
+        }
+        .store(in: &cancellables)
+    }
+}

Modules/TestableShareExtension/Package.swift

@@ -0,0 +1,25 @@
+// swift-tools-version: 5.10
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import PackageDescription
+
+let package = Package(
+    name: "TestableShareExtension",
+    platforms: [.iOS(.v17), .macOS(.v14)],
+    products: [
+        .library(name: "TestableShareExtension", targets: ["TestableShareExtension"])
+    ],
+    dependencies: [
+        .package(path: "../InboxComposer"),
+        .package(path: "../InboxKeychain"),
+        .package(path: "../InboxSnapshotTesting"),
+        .package(path: "../InboxTesting"),
+    ],
+    targets: [
+        .target(name: "TestableShareExtension", dependencies: ["InboxComposer", "InboxKeychain"]),
+        .testTarget(
+            name: "ShareExtensionTests",
+            dependencies: ["InboxSnapshotTesting", "InboxTesting", "TestableShareExtension"]
+        ),
+    ]
+)

Modules/TestableShareExtension/Sources/Draft/DraftPrecomposer.swift

@@ -0,0 +1,94 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import InboxComposer
+import proton_app_uniffi
+import UIKit
+import UniformTypeIdentifiers
+
+enum DraftPrecomposer {
+    static func populate(draft: AppDraftProtocol, with sharedContent: SharedContent) async throws {
+        if let subject = sharedContent.subject {
+            try draft.setSubject(subject: subject).get()
+        }
+
+        if let inlineImageHTML = try await add(attachments: sharedContent.attachments, to: draft.attachmentList()) {
+            try draft.prependToBody(text: inlineImageHTML.content)
+        }
+
+        if let sharedBody = sharedContent.body {
+            try draft.prependToBody(text: sharedBody)
+        }
+    }
+
+    private static func add(attachments: [NSItemProvider], to attachmentList: AttachmentListProtocol) async throws -> InlineImageHTML? {
+        let uploadFolder: URL = URL(fileURLWithPath: attachmentList.attachmentUploadDirectory())
+
+        var cids: [String] = []
+
+        for attachment in attachments {
+            let url = try await saveFileRepresentation(of: attachment, intoDirectory: uploadFolder)
+            let path = url.path(percentEncoded: false)
+
+            if attachment.hasImageRepresentation {
+                if try url.isScreenshotInPlistFormat() {
+                    try await extractImageContent(of: attachment, into: url)
+                }
+
+                let cid = try await attachmentList.addInline(path: path, filenameOverride: nil).get()
+                cids.append(cid)
+            } else {
+                try await attachmentList.add(path: path, filenameOverride: nil).get()
+            }
+        }
+
+        return cids.isEmpty ? nil : InlineImageHTML(cids: cids)
+    }
+
+    private static func saveFileRepresentation(of attachment: NSItemProvider, intoDirectory persistentDirectory: URL) async throws -> URL {
+        try await attachment.performOnFileRepresentation { shortLivedURL in
+            try FileManager.default.moveToUniqueURL(file: shortLivedURL, to: persistentDirectory)
+        }
+    }
+
+    private static func extractImageContent(of attachment: NSItemProvider, into url: URL) async throws {
+        let image = try await attachment.loadItem(forTypeIdentifier: UTType.image.identifier) as? UIImage
+        try image?.jpegData(compressionQuality: JPEG.compressionQuality)?.write(to: url)
+    }
+}
+
+private extension AppDraftProtocol {
+    func prependToBody(text: String) throws {
+        let currentBody = body()
+        try setBody(body: text + currentBody).get()
+    }
+}
+
+private extension URL {
+    func isScreenshotInPlistFormat() throws -> Bool {
+        let plistFileSignature = "bplist00".data(using: .ascii)!
+        let handle = try FileHandle(forReadingFrom: self)
+
+        defer {
+            try? handle.close()
+        }
+
+        let fileSignature = try handle.read(upToCount: plistFileSignature.count)
+        return fileSignature == plistFileSignature
+    }
+}

Modules/TestableShareExtension/Sources/Draft/SharedItemsParser.swift

@@ -0,0 +1,50 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import Foundation
+import InboxCore
+import UniformTypeIdentifiers
+
+struct SharedContent {
+    let subject: String?
+    let body: String?
+    let attachments: [NSItemProvider]
+}
+
+enum SharedItemsParser {
+    static func parse(extensionItems: [NSExtensionItem]) async throws -> SharedContent {
+        for extensionItem in extensionItems {
+            guard let attachments = extensionItem.attachments else { continue }
+
+            let registeredTypeIdentifiers = attachments.flatMap(\.registeredTypeIdentifiers)
+            let isSharingSafariPage = registeredTypeIdentifiers == [UTType.url.identifier]
+            let isSharingTextFromSelection = registeredTypeIdentifiers == [UTType.plainText.identifier]
+
+            if isSharingSafariPage {
+                let link = try await attachments[0].loadString()
+                let body = "<a href=\"\(link)\">\(link)</a>"
+                return .init(subject: extensionItem.attributedContentText?.string, body: body, attachments: [])
+            } else if isSharingTextFromSelection {
+                return .init(subject: nil, body: extensionItem.attributedContentText?.string, attachments: [])
+            }
+        }
+
+        let allAttachments = extensionItems.compactMap(\.attachments).flatMap(\.self)
+        return .init(subject: nil, body: nil, attachments: allAttachments)
+    }
+}

Modules/TestableShareExtension/Sources/Payments/UpsellConfiguration.swift

@@ -0,0 +1,27 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import InboxIAP
+import proton_app_uniffi
+
+extension UpsellConfiguration {
+    /// The upsell screen should always show this particular plan.
+    static func mail(apiEnvId: ApiEnvId) -> Self {
+        .init(planName: "mail2022", arePaymentsEnabled: apiEnvId.arePaymentsEnabled)
+    }
+}

Modules/TestableShareExtension/Sources/UI/ErrorScreen.swift

@@ -0,0 +1,87 @@
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import InboxCore
+import InboxCoreUI
+import InboxDesignSystem
+import proton_app_uniffi
+import SwiftUI
+
+struct ErrorScreen: View {
+    @Environment(\.openURL) private var openURL
+
+    let error: Error
+    let dismissExtension: () -> Void
+
+    init(error: any Error, dismissExtension: @escaping () -> Void) {
+        self.error = error
+        self.dismissExtension = dismissExtension
+    }
+
+    var body: some View {
+        VStack(spacing: DS.Spacing.extraLarge) {
+            Spacer()
+
+            Text(errorMessage)
+                .multilineTextAlignment(.center)
+
+            Spacer()
+
+            if error.shouldPromptToSignIn {
+                Button(L10n.openApp.string) {
+                    openURL(URL(string: "\(Bundle.URLScheme.protonmail):")!)
+                    dismissExtension()
+                }
+            }
+
+            Button(CommonL10n.cancel.string) {
+                dismissExtension()
+            }
+        }
+        .buttonStyle(BigButtonStyle())
+        .padding(DS.Spacing.huge)
+        .padding(.vertical, DS.Spacing.extraLarge)
+        .background(DS.Color.BackgroundInverted.norm)
+    }
+
+    private var errorMessage: String {
+        if error.shouldPromptToSignIn {
+            L10n.needToSignIn.string
+        } else {
+            error.localizedDescription
+        }
+    }
+}
+
+private extension Error {
+    var shouldPromptToSignIn: Bool {
+        switch self as? UserSessionError {
+        case .reason(.userSessionNotInitialized):
+            true
+        default:
+            false
+        }
+    }
+}
+
+#Preview("with sign-in option") {
+    ErrorScreen(error: UserSessionError.reason(.userSessionNotInitialized), dismissExtension: {})
+}
+
+#Preview("without sign-in option") {
+    ErrorScreen(error: NSError(domain: "", code: 0), dismissExtension: {})
+}

Modules/TestableShareExtension/Sources/UI/ShareScreen/ShareScreen.swift

@@ -0,0 +1,74 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import InboxComposer
+import InboxCoreUI
+import proton_app_uniffi
+import SwiftUI
+
+public struct ShareScreen: View {
+    @ObservedObject private var model: ShareScreenModel
+    @StateObject private var toastStateStore = ToastStateStore(initialState: .initial)
+
+    public init(model: ShareScreenModel) {
+        self.model = model
+    }
+
+    public var body: some View {
+        switch model.state {
+        case .preparing:
+            Color.clear
+                .task {
+                    await model.prepare()
+                }
+        case .locked(let lockScreenType, let mailSession):
+            LockScreen(
+                state: .init(type: lockScreenType),
+                mailSession: mailSession as! LockScreen.MailSessionType,
+                dismissLock: {
+                    Task {
+                        await model.onAppUnlocked()
+                    }
+                }
+            )
+            .padding(.top)
+        case .composing(let draft, let dependencies, let upsellCoordinator):
+            ComposerScreen(
+                draft: draft,
+                draftOrigin: .new,
+                dependencies: dependencies,
+                isAddingAttachmentsEnabled: false,
+                onDismiss: { reason in
+                    model.onComposerDismissed(reason: reason)
+                }
+            )
+            .overlay {
+                ToastSceneView()
+            }
+            .environmentObject(toastStateStore)
+            .environmentObject(upsellCoordinator)
+        case .error(let error):
+            ErrorScreen(
+                error: error,
+                dismissExtension: {
+                    model.dismissShareExtension(error: error)
+                },
+            )
+        }
+    }
+}

Modules/TestableShareExtension/Sources/UI/ShareScreen/ShareScreenModel.swift

@@ -0,0 +1,168 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import InboxComposer
+import InboxCore
+import InboxCoreUI
+import InboxIAP
+import proton_app_uniffi
+import SwiftUI
+
+@MainActor
+public final class ShareScreenModel: ObservableObject {
+    typealias MakeNewDraft = (MailUserSession, DraftCreateMode) async throws -> AppDraftProtocol
+
+    enum ViewState {
+        case preparing
+        case composing(AppDraftProtocol, ComposerScreen.Dependencies, UpsellCoordinator)
+        case locked(LockScreenState.LockScreenType, MailSessionProtocol)
+        case error(Error)
+    }
+
+    @Published private(set) var state: ViewState = .preparing
+    @Published private(set) public var alert: String?
+
+    private let extensionContext: NSExtensionContext
+    private let makeNewDraft: MakeNewDraft
+    private let sessionHolder: SessionHolder
+    private let upsellConfiguration: UpsellConfiguration
+
+    public convenience init(apiEnvId: ApiEnvId, extensionContext: NSExtensionContext) {
+        self.init(
+            apiEnvId: apiEnvId,
+            extensionContext: extensionContext,
+            makeMailSession: { try createMailSession(params: $0, keyChain: $1, hvNotifier: $2, deviceInfoProvider: $3).get() },
+            makeNewDraft: { try await newDraft(session: $0, createMode: $1).get() }
+        )
+    }
+
+    init(
+        apiEnvId: ApiEnvId,
+        extensionContext: NSExtensionContext,
+        makeMailSession: @escaping SessionHolder.MakeMailSession,
+        makeNewDraft: @escaping MakeNewDraft
+    ) {
+        self.extensionContext = extensionContext
+        self.makeNewDraft = makeNewDraft
+        sessionHolder = .init(apiEnvId: apiEnvId, makeMailSession: makeMailSession)
+        upsellConfiguration = .mail(apiEnvId: apiEnvId)
+    }
+
+    func prepare() async {
+        do {
+            let mailSession = try sessionHolder.mailSession()
+            let appProtection = try await mailSession.appProtection().get()
+
+            if let lockScreenType = appProtection.lockScreenType {
+                state = .locked(lockScreenType, mailSession)
+            } else {
+                await onAppUnlocked()
+            }
+        } catch {
+            AppLogger.log(error: error, category: .shareExtension)
+            state = .error(error)
+        }
+    }
+
+    func onAppUnlocked() async {
+        do {
+            let userSession = try await sessionHolder.primaryUserSession()
+            let draft = try await prepareDraft(userSession: userSession)
+
+            let dependencies = ComposerScreen.Dependencies(
+                contactProvider: .productionInstance(session: userSession),
+                userSession: userSession
+            )
+
+            let upsellCoordinator = UpsellCoordinator(mailUserSession: userSession, configuration: upsellConfiguration)
+
+            state = .composing(draft, dependencies, upsellCoordinator)
+        } catch {
+            AppLogger.log(error: error, category: .shareExtension)
+            state = .error(error)
+        }
+    }
+
+    func onComposerDismissed(reason: ComposerDismissReason) {
+        switch reason {
+        case .dismissedManually, .draftDiscarded:
+            dismissShareExtension(error: NSError.userCancelled)
+        case .messageScheduled(let messageID), .messageSent(let messageID):
+            alert = L10n.Sending.sendingInProgress.string
+
+            Task {
+                do {
+                    try await waitUntilMessageSendingIsFinished(messageID: messageID)
+                    alert = L10n.Sending.messageSent.string
+                } catch {
+                    AppLogger.log(error: error, category: .shareExtension)
+                    alert = error.localizedDescription
+                }
+
+                try? await Task.sleep(for: .seconds(2))
+
+                dismissShareExtension(error: nil)
+            }
+        }
+    }
+
+    func dismissShareExtension(error: Error?) {
+        if let error {
+            AppLogger.log(message: "Sharing cancelled", category: .shareExtension)
+            extensionContext.cancelRequest(withError: error)
+        } else {
+            extensionContext.completeRequest(returningItems: nil) { expired in
+                if expired {
+                    AppLogger.log(message: "Sharing interrupted", category: .shareExtension, isError: true)
+                } else {
+                    AppLogger.log(message: "Sharing completed", category: .shareExtension)
+                }
+            }
+        }
+    }
+
+    private func prepareDraft(userSession: MailUserSession) async throws -> AppDraftProtocol {
+        let draft = try await makeNewDraft(userSession, .empty)
+
+        let inputItems = extensionContext.inputItems.map { $0 as! NSExtensionItem }
+        let sharedContent = try await SharedItemsParser.parse(extensionItems: inputItems)
+        try await DraftPrecomposer.populate(draft: draft, with: sharedContent)
+
+        return draft
+    }
+
+    private func waitUntilMessageSendingIsFinished(messageID: ID) async throws {
+        let userSession = try await sessionHolder.primaryUserSession()
+        let sendResultPublisher = SendResultPublisher(userSession: userSession)
+
+        for await sendResultInfo in sendResultPublisher.results.values where sendResultInfo.messageId == messageID {
+            switch sendResultInfo.type {
+            case .scheduling, .sending:
+                break
+            case .scheduled, .sent:
+                return
+            case .error(let error):
+                throw error
+            }
+        }
+    }
+}
+
+private extension NSError {
+    static let userCancelled = NSError(domain: Bundle.main.bundleIdentifier!, code: NSUserCancelledError)
+}

Modules/TestableShareExtension/Sources/Uniffi/SessionHolder.swift

@@ -0,0 +1,64 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import AccountChallenge
+import InboxCore
+import InboxKeychain
+import proton_app_uniffi
+
+/**
+ The purpose of this class is to guarantee that MailSession and the primary MailUserSession are:
+ - only created once
+ - retained for the entire lifetime of the Share extension
+ */
+final class SessionHolder {
+    typealias MakeMailSession = (MailSessionParams, OsKeyChain, ChallengeNotifier?, DeviceInfoProvider?) throws -> MailSessionProtocol
+
+    private let apiEnvId: ApiEnvId
+    private let makeMailSession: MakeMailSession
+
+    private var cachedMailSession: MailSessionProtocol?
+    private var cachedUserSession: MailUserSession?
+
+    init(apiEnvId: ApiEnvId, makeMailSession: @escaping MakeMailSession) {
+        self.apiEnvId = apiEnvId
+        self.makeMailSession = makeMailSession
+    }
+
+    func mailSession() throws -> MailSessionProtocol {
+        if let cachedMailSession {
+            return cachedMailSession
+        } else {
+            let apiConfig = ApiConfig(envId: apiEnvId)
+            let params = MailSessionParamsFactory.make(origin: .iosShareExt, apiConfig: apiConfig)
+            let newMailSession = try makeMailSession(params, KeychainSDKWrapper(), nil, ChallengePayloadProvider())
+            cachedMailSession = newMailSession
+            return newMailSession
+        }
+    }
+
+    func primaryUserSession() async throws -> MailUserSession {
+        if let cachedUserSession {
+            return cachedUserSession
+        } else {
+            let newUserSession = try await mailSession().toPrimaryUserSession().get()
+            cachedUserSession = newUserSession
+            return newUserSession
+        }
+    }
+}

Modules/TestableShareExtension/Sources/Utils/L10n.swift

@@ -0,0 +1,31 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import Foundation
+
+enum L10n {
+    enum Sending {
+        static let sendingInProgress = LocalizedStringResource("Sending...", bundle: .module, comment: "Alert shown while the message is being sent")
+
+        static let messageSent = LocalizedStringResource("Message sent!", bundle: .module, comment: "Alert shown after the message has been sent")
+    }
+
+    static let needToSignIn = LocalizedStringResource("You need to sign-in to Proton Mail to share content.", bundle: .module, comment: "Error message when attempting to use the Share extension without being logged in")
+
+    static let openApp = LocalizedStringResource("Open Proton Mail", bundle: .module, comment: "Button to open the main app from the Share extension")
+}

Modules/TestableShareExtension/Sources/Utils/NSItemProvider+Extensions.swift

@@ -0,0 +1,54 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import UIKit
+import UniformTypeIdentifiers
+
+extension NSItemProvider {
+    var hasImageRepresentation: Bool {
+        hasItemConformingToTypeIdentifier(UTType.image.identifier)
+    }
+
+    func loadString() async throws -> String {
+        try await withCheckedThrowingContinuation { continuation in
+            _ = loadObject(ofClass: String.self) { value, error in
+                if let error {
+                    continuation.resume(throwing: error)
+                } else {
+                    continuation.resume(returning: value!)
+                }
+            }
+        }
+    }
+
+    func performOnFileRepresentation<T>(block: @escaping (URL) throws -> T) async throws -> T {
+        try await withCheckedThrowingContinuation { continuation in
+            _ = loadFileRepresentation(for: .data) { shortLivedURL, _, error in
+                continuation.resume(
+                    with: .init {
+                        guard let shortLivedURL else {
+                            throw error!
+                        }
+
+                        return try block(shortLivedURL)
+                    }
+                )
+            }
+        }
+    }
+}

Modules/TestableShareExtension/Tests/Doubles/ExtensionContextSpy.swift

@@ -0,0 +1,35 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import Foundation
+
+final class ExtensionContextSpy: NSExtensionContext {
+    var stubbedExpirationFlag = false
+
+    private(set) var cancelRequestInvocations: [Error] = []
+    private(set) var completeRequestInvocations: [[Any]?] = []
+
+    override func cancelRequest(withError error: any Error) {
+        cancelRequestInvocations.append(error)
+    }
+
+    override func completeRequest(returningItems items: [Any]?, completionHandler: ((Bool) -> Void)? = nil) {
+        completeRequestInvocations.append(items)
+        completionHandler?(stubbedExpirationFlag)
+    }
+}

Modules/TestableShareExtension/Tests/Draft/DraftPrecomposerTests.swift

@@ -0,0 +1,164 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import Foundation
+import Testing
+import UIKit
+import UniformTypeIdentifiers
+
+@testable import InboxComposer
+@testable import TestableShareExtension
+
+final class DraftPrecomposerTests {
+    private let sut = DraftPrecomposer.self
+    private let draft = MockDraft.emptyMockDraft
+    private let fileManager = FileManager.default
+    private let testDir: URL
+    private let attachmentSourceDir: URL
+    private let attachmentUploadDir: URL
+
+    init() throws {
+        testDir = fileManager.temporaryDirectory.appending(path: UUID().uuidString, directoryHint: .isDirectory)
+        attachmentSourceDir = testDir.appending(path: "attachment_source", directoryHint: .isDirectory)
+        attachmentUploadDir = testDir.appending(path: "attachment_upload", directoryHint: .isDirectory)
+
+        for dir in [attachmentSourceDir, attachmentUploadDir] {
+            try fileManager.createDirectory(at: dir, withIntermediateDirectories: true)
+        }
+
+        draft.mockAttachmentList.attachmentUploadDirectoryURL = attachmentUploadDir
+    }
+
+    deinit {
+        try! fileManager.removeItem(at: testDir)
+    }
+
+    @Test
+    func populatingDraftWithoutAttachments() async throws {
+        let sharedContent = SharedContent(
+            subject: "A subject",
+            body: "Some body",
+            attachments: []
+        )
+
+        try await sut.populate(draft: draft, with: sharedContent)
+
+        #expect(draft.subject() == "A subject")
+        #expect(draft.body() == "Some body")
+        #expect(draft.mockAttachmentList.capturedAddCalls.count == 0)
+    }
+
+    @Test
+    func movesNonInlineAttachmentsToUploadDirectoryBeforeAdding() async throws {
+        let sourceURLs = (0..<3).map { index in
+            attachmentSourceDir.appending(path: "data-\(index).txt")
+        }
+
+        let sharedContent = SharedContent(
+            subject: nil,
+            body: nil,
+            attachments: try TestDataFactory.stubShortLivedData(in: sourceURLs)
+        )
+
+        try await sut.populate(draft: draft, with: sharedContent)
+
+        let expectedAttachmentPaths = sourceURLs.map {
+            attachmentUploadDir.appending(path: $0.lastPathComponent).path()
+        }
+
+        #expect(Set(draft.mockAttachmentList.capturedAddCalls.map(\.path)) == Set(expectedAttachmentPaths))
+
+        for path in expectedAttachmentPaths {
+            #expect(FileManager.default.fileExists(atPath: path))
+        }
+    }
+
+    @Test
+    func insertsInlineAttachmentReferencesInBody() async throws {
+        let sourceURLs = (0..<3).map { index in
+            attachmentSourceDir.appending(path: "image-\(index).png")
+        }
+
+        let sharedContent = SharedContent(
+            subject: nil,
+            body: "Some body",
+            attachments: try TestDataFactory.stubImages(in: sourceURLs)
+        )
+
+        try await sut.populate(draft: draft, with: sharedContent)
+
+        let expectedBody = """
+            Some body<img src="cid:12345" style="max-width: 100%;"><br><img src="cid:12345" style="max-width: 100%;"><br><img src="cid:12345" style="max-width: 100%;"><br>
+            """
+        #expect(draft.body() == expectedBody)
+
+        let expectedAttachmentPaths = sourceURLs.map {
+            attachmentUploadDir.appending(path: $0.lastPathComponent).path()
+        }
+
+        #expect(Set(draft.mockAttachmentList.capturedAddInlineCalls.map(\.path)) == Set(expectedAttachmentPaths))
+    }
+
+    @Test
+    func extractsImagesFromScreenshotPlists() async throws {
+        let sourceURLs = (0..<3).map { index in
+            attachmentSourceDir.appending(path: "image-\(index).png")
+        }
+
+        let sharedContent = SharedContent(
+            subject: nil,
+            body: "Some body",
+            attachments: try TestDataFactory.stubScreenshots(in: sourceURLs)
+        )
+
+        try await sut.populate(draft: draft, with: sharedContent)
+
+        let expectedBody = """
+            Some body<img src="cid:12345" style="max-width: 100%;"><br><img src="cid:12345" style="max-width: 100%;"><br><img src="cid:12345" style="max-width: 100%;"><br>
+            """
+        #expect(draft.body() == expectedBody)
+
+        let expectedAttachmentPaths = sourceURLs.map {
+            attachmentUploadDir.appending(path: $0.lastPathComponent)
+        }
+
+        #expect(expectedAttachmentPaths.count == 3)
+
+        for url in expectedAttachmentPaths {
+            let data = try Data(contentsOf: url)
+            #expect(UIImage(data: data) != nil)
+        }
+    }
+
+    @Test
+    func handlesAttachmentLoadingFailures() async throws {
+        let sharedContent = SharedContent(
+            subject: nil,
+            body: "Some body",
+            attachments: [TestDataFactory.stubError()]
+        )
+
+        await #expect(throws: NSError.self) {
+            try await self.sut.populate(draft: self.draft, with: sharedContent)
+        }
+
+        #expect(draft.body() == .empty)
+        #expect(draft.mockAttachmentList.capturedAddCalls.count == 0)
+        #expect(draft.mockAttachmentList.capturedAddInlineCalls.count == 0)
+    }
+}

Modules/TestableShareExtension/Tests/Draft/SharedItemsParserTests.swift

@@ -0,0 +1,108 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import Testing
+import UniformTypeIdentifiers
+
+@testable import TestableShareExtension
+
+final class SharedItemsParserTests {
+    private let sut = SharedItemsParser.self
+
+    @Test
+    func testSharingSeveralImagesFromPhotosApp() async throws {
+        let extensionItems = emulateSharingSeveralImagesFromPhotosApp(count: 5)
+
+        let sharedContent = try await sut.parse(extensionItems: extensionItems)
+
+        #expect(sharedContent.subject == nil)
+        #expect(sharedContent.body == nil)
+        #expect(sharedContent.attachments == extensionItems[0].attachments)
+    }
+
+    @Test
+    func testSharingSeveralImagesAndFilesFromFilesApp() async throws {
+        let extensionItems = emulateSharingSeveralImagesAndFilesFromFilesApp(imageCount: 3, fileCount: 2)
+
+        let sharedContent = try await sut.parse(extensionItems: extensionItems)
+
+        #expect(sharedContent.subject == nil)
+        #expect(sharedContent.body == nil)
+        #expect(sharedContent.attachments == extensionItems[0].attachments)
+    }
+
+    @Test
+    func testSharingSafariPage() async throws {
+        let extensionItems = emulateSharingSafariPage(
+            url: URL(string: "https://example.com")!,
+            pageTitle: "An example webpage"
+        )
+
+        let sharedContent = try await sut.parse(extensionItems: extensionItems)
+
+        #expect(sharedContent.subject == "An example webpage")
+        #expect(sharedContent.body == #"<a href="https://example.com">https://example.com</a>"#)
+        #expect(sharedContent.attachments == [])
+    }
+
+    @Test
+    func testSharingSelectedText() async throws {
+        let extensionItems = emulateSharing(selectedText: "Lorem ipsum")
+
+        let sharedContent = try await sut.parse(extensionItems: extensionItems)
+
+        #expect(sharedContent.subject == nil)
+        #expect(sharedContent.body == "Lorem ipsum")
+        #expect(sharedContent.attachments == [])
+    }
+
+    // MARK: realistic scenarios
+
+    private func emulateSharingSeveralImagesFromPhotosApp(count: UInt) -> [NSExtensionItem] {
+        let extensionItem = NSExtensionItem()
+        extensionItem.attachments = TestDataFactory.makeItemProviders(types: [.jpeg, .heic], count: count)
+        return [extensionItem]
+    }
+
+    private func emulateSharingSeveralImagesAndFilesFromFilesApp(imageCount: UInt, fileCount: UInt) -> [NSExtensionItem] {
+        let images = TestDataFactory.makeItemProviders(types: [.heic, .fileURL], count: imageCount)
+        let files = TestDataFactory.makeItemProviders(types: [.plainText, .fileURL], count: fileCount)
+
+        let extensionItem = NSExtensionItem()
+        extensionItem.attachments = images + files
+        return [extensionItem]
+    }
+
+    private func emulateSharingSafariPage(url: URL, pageTitle: String) -> [NSExtensionItem] {
+        let extensionItem = NSExtensionItem()
+        extensionItem.attributedContentText = .init(string: pageTitle)
+        extensionItem.attachments = [
+            .init(item: url as NSSecureCoding, typeIdentifier: UTType.url.identifier)
+        ]
+        return [extensionItem]
+    }
+
+    private func emulateSharing(selectedText: String) -> [NSExtensionItem] {
+        let extensionItem = NSExtensionItem()
+        extensionItem.attributedContentText = .init(string: selectedText)
+        extensionItem.attachments = [
+            .init(item: "this is irrelevant" as NSSecureCoding, typeIdentifier: UTType.plainText.identifier)
+        ]
+        return [extensionItem]
+    }
+}

Modules/TestableShareExtension/Tests/TestDataFactory.swift

@@ -0,0 +1,109 @@
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import Foundation
+import UIKit
+import UniformTypeIdentifiers
+
+enum TestDataFactory {
+    static func makeItemProviders(types: [UTType], count: UInt) -> [NSItemProvider] {
+        (0..<count).map { index in
+            let itemProvider = NSItemProvider()
+
+            for type in types {
+                let url = URL(fileURLWithPath: "attachments/\(index)-\(type.identifier)")
+
+                itemProvider.registerFileRepresentation(for: type) { completion in
+                    completion(url, true, nil)
+                    return nil
+                }
+            }
+
+            return itemProvider
+        }
+    }
+
+    static func stubShortLivedData(in urls: [URL]) throws -> [NSItemProvider] {
+        let data = Data("foo".utf8)
+
+        return try urls.map { url in
+            try data.write(to: url)
+
+            let itemProvider = NSItemProvider()
+
+            itemProvider.registerFileRepresentation(for: .data) { completion in
+                completion(url, false, nil)
+                try! FileManager.default.removeItem(at: url)
+                return nil
+            }
+
+            return itemProvider
+        }
+    }
+
+    static func stubImages(in urls: [URL]) throws -> [NSItemProvider] {
+        let image = UIImage(systemName: "checkmark")!
+
+        return try urls.map { url in
+            try image.pngData()!.write(to: url)
+
+            let itemProvider = NSItemProvider()
+
+            itemProvider.registerFileRepresentation(for: .image) { completion in
+                completion(url, true, nil)
+                return nil
+            }
+
+            return itemProvider
+        }
+    }
+
+    static func stubScreenshots(in urls: [URL]) throws -> [NSItemProvider] {
+        let image = UIImage(systemName: "checkmark")!
+
+        let plist: [String: Any] = ["foo": "bar"]
+        let plistData = try PropertyListSerialization.data(fromPropertyList: plist, format: .binary, options: 0)
+
+        return try urls.map { url in
+            try plistData.write(to: url)
+
+            let itemProvider = NSItemProvider()
+
+            itemProvider.registerFileRepresentation(for: .data) { completion in
+                completion(url, false, nil)
+                return nil
+            }
+
+            itemProvider.registerItem(forTypeIdentifier: UTType.image.identifier) { completion, _, _ in
+                completion!(image, nil)
+            }
+
+            return itemProvider
+        }
+    }
+
+    static func stubError() -> NSItemProvider {
+        let itemProvider = NSItemProvider()
+
+        itemProvider.registerFileRepresentation(for: .data) { completion in
+            completion(nil, false, TestError())
+            return nil
+        }
+
+        return itemProvider
+    }
+}

Modules/TestableShareExtension/Tests/TestError.swift

@@ -0,0 +1,23 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import Foundation
+
+struct TestError: LocalizedError, Equatable {
+    let errorDescription: String? = "Something failed."
+}

Modules/TestableShareExtension/Tests/UI/ErrorViewSnapshotTests.swift

@@ -0,0 +1,38 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import InboxSnapshotTesting
+import proton_app_uniffi
+import Testing
+
+@testable import TestableShareExtension
+
+@MainActor
+struct ErrorScreenSnapshotTests {
+    @Test
+    func withButtonToOpenApp() {
+        let sut = ErrorScreen(error: UserSessionError.reason(.userSessionNotInitialized), dismissExtension: {})
+        assertSnapshotsOnIPhoneX(of: sut)
+    }
+
+    @Test
+    func withoutButtonToOpenApp() {
+        let sut = ErrorScreen(error: TestError(), dismissExtension: {})
+        assertSnapshotsOnIPhoneX(of: sut)
+    }
+}

Modules/TestableShareExtension/Tests/UI/ShareScreen/ShareScreenModelTests.swift

@@ -0,0 +1,124 @@
+//
+// Copyright (c) 2025 Proton Technologies AG
+//
+// This file is part of Proton Mail.
+//
+// Proton Mail is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Proton Mail is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Proton Mail. If not, see https://www.gnu.org/licenses/.
+
+import InboxTesting
+import proton_app_uniffi
+import Testing
+
+@testable import InboxComposer
+@testable import TestableShareExtension
+
+@MainActor
+final class ShareScreenModelTests {
+    private let extensionContext = ExtensionContextSpy()
+    private let mailSession = MailSessionSpy()
+    private var stubbedMailSessionResult: Result<MailSessionProtocol, TestError>
+    private var stubbedNewDraftResult: Result<AppDraftProtocol, TestError>
+
+    private lazy var sut = ShareScreenModel(
+        apiEnvId: .atlas,
+        extensionContext: extensionContext,
+        makeMailSession: { [unowned self] _, _, _, _ in
+            try stubbedMailSessionResult.get()
+        },
+        makeNewDraft: { [unowned self] _, _ in
+            try stubbedNewDraftResult.get()
+        }
+    )
+
+    init() {
+        mailSession.primaryUserSessionStub = MailUserSessionSpy(id: "")
+        stubbedMailSessionResult = .success(mailSession)
+        stubbedNewDraftResult = .success(MockDraft.emptyMockDraft)
+    }
+
+    @Test(arguments: [AppProtection.biometrics, .pin])
+    func showsLockScreenIfAppProtectionIsSet(appProtection: AppProtection) async {
+        mailSession.appProtectionStub = appProtection
+
+        await sut.prepare()
+
+        switch sut.state {
+        case .locked(appProtection.lockScreenType, _):
+            break
+        default:
+            Issue.record("unexpected state: \(sut.state)")
+        }
+    }
+
+    @Test
+    func showsComposerIfAppProtectionIsNotSet() async {
+        mailSession.appProtectionStub = .none
+
+        await sut.prepare()
+
+        switch sut.state {
+        case .composing:
+            break
+        default:
+            Issue.record("unexpected state: \(sut.state)")
+        }
+    }
+
+    @Test
+    func showsErrorScreenIfInitialSetupFails() async throws {
+        stubbedMailSessionResult = .failure(TestError())
+
+        await sut.prepare()
+
+        switch sut.state {
+        case .error(_ as TestError):
+            break
+        default:
+            Issue.record("unexpected state: \(sut.state)")
+        }
+    }
+
+    @Test
+    func showsErrorScreenIfPreparingComposerScreenFails() async throws {
+        stubbedNewDraftResult = .failure(TestError())
+
+        await sut.prepare()
+
+        switch sut.state {
+        case .error(_ as TestError):
+            break
+        default:
+            Issue.record("unexpected state: \(sut.state)")
+        }
+    }
+
+    @Test
+    func dismissingWithErrorCancelsTheRequestOfTheContext() {
+        sut.dismissShareExtension(error: TestError())
+
+        #expect(extensionContext.cancelRequestInvocations.count == 1)
+        #expect(extensionContext.cancelRequestInvocations.first is TestError)
+        #expect(extensionContext.completeRequestInvocations.count == 0)
+    }
+
+    @Test(arguments: [true, false])
+    func dismissingWithoutErrorCompletesTheRequestOfTheContext(expirationFlag: Bool) {
+        extensionContext.stubbedExpirationFlag = expirationFlag
+
+        sut.dismissShareExtension(error: nil)
+
+        #expect(extensionContext.completeRequestInvocations.count == 1)
+        #expect(extensionContext.cancelRequestInvocations.count == 0)
+    }
+}

ShareExtension.entitlements

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>com.apple.security.application-groups</key>
+	<array>
+		<string>group.me.proton.mail</string>
+	</array>
+</dict>
+</plist>

TestPlans/AllUnitAndSnapshotTests.xctestplan

@@ -20,6 +20,13 @@
     "testTimeoutsEnabled" : true
   },
   "testTargets" : [
+    {
+      "target" : {
+        "containerPath" : "container:Modules\/InboxIAP",
+        "identifier" : "InboxIAPTests",
+        "name" : "InboxIAPTests"
+      }
+    },
     {
       "target" : {
         "containerPath" : "container:Modules\/InboxCoreUI",
@@ -29,9 +36,16 @@
     },
     {
       "target" : {
-        "containerPath" : "container:Modules\/InboxComposer",
-        "identifier" : "InboxComposerTests",
-        "name" : "InboxComposerTests"
+        "containerPath" : "container:Modules\/TestableShareExtension",
+        "identifier" : "ShareExtensionTests",
+        "name" : "ShareExtensionTests"
+      }
+    },
+    {
+      "target" : {
+        "containerPath" : "container:Modules\/TestableNotificationService",
+        "identifier" : "NotificationServiceTests",
+        "name" : "NotificationServiceTests"
       }
     },
     {
@@ -41,6 +55,13 @@
         "name" : "InboxRSVPTests"
       }
     },
+    {
+      "target" : {
+        "containerPath" : "container:Modules\/InboxComposer",
+        "identifier" : "InboxComposerTests",
+        "name" : "InboxComposerTests"
+      }
+    },
     {
       "target" : {
         "containerPath" : "container:Modules\/InboxKeychain",
@@ -55,20 +76,6 @@
         "name" : "ProtonMailTest"
       }
     },
-    {
-      "target" : {
-        "containerPath" : "container:Modules\/InboxIAP",
-        "identifier" : "InboxIAPTests",
-        "name" : "InboxIAPTests"
-      }
-    },
-    {
-      "target" : {
-        "containerPath" : "container:Modules\/TestableNotificationService",
-        "identifier" : "NotificationServiceTests",
-        "name" : "NotificationServiceTests"
-      }
-    },
     {
       "target" : {
         "containerPath" : "container:Modules\/InboxContacts",

fastlane/Fastfile

@@ -4,6 +4,7 @@ default_platform(:ios)
 
 APP_IDENTIFIER = "ch.protonmail.protonmail"
 NOTIFICATION_EXTENSION_IDENTIFIER = "ch.protonmail.protonmail.notifications"
+SHARE_EXTENSION_IDENTIFIER = "ch.protonmail.protonmail.Share"
 DEVELOPER_KEYCHAIN_NAME = "PROTONMAIL_IOS_CERTIFICATE_KEYCHAIN"
 DEVELOPER_KEYCHAIN_PASSWORD = "QrniqyS3LWTH3Ji"
 CERTIFICATE_PATH = "fastlane/Certificates.p12"
@@ -54,7 +55,8 @@ platform :ios do
   def get_xcode_profile
     ids = [
       APP_IDENTIFIER,
-      NOTIFICATION_EXTENSION_IDENTIFIER
+      NOTIFICATION_EXTENSION_IDENTIFIER,
+      SHARE_EXTENSION_IDENTIFIER
     ]
 
     ids.each do |id|

project.yml

@@ -74,6 +74,9 @@ packages:
   TestableNotificationService:
     path: Modules/TestableNotificationService
     group: Modules
+  TestableShareExtension:
+    path: Modules/TestableShareExtension
+    group: Modules
   TryCatch:
     path: Modules/TryCatch
     group: Modules
@@ -100,6 +103,33 @@ settings:
     QA:
       SWIFT_ACTIVE_COMPILATION_CONDITIONS: "QA"
 
+targetTemplates:
+  Extension:
+    type: app-extension
+    platform: iOS
+    scheme: {}
+    sources:
+      - path: Modules/${target_name}/Sources
+    settings:
+      base:
+        CODE_SIGN_IDENTITY: "iPhone Distribution: Proton AG (2SB5Z68H26)"
+        CODE_SIGN_ENTITLEMENTS: ${target_name}.entitlements
+        PRODUCT_BUNDLE_IDENTIFIER: ${bundle_identifier}
+        PROVISIONING_PROFILE_SPECIFIER: ${release_provisioning_profile}
+      configs:
+        Debug:
+          CODE_SIGN_IDENTITY: "Apple Development"
+          CODE_SIGN_STYLE: Automatic
+          PROVISIONING_PROFILE_SPECIFIER: ""
+    info:
+      path: Modules/${target_name}/Sources/SupportingFiles/Info.plist
+      properties:
+        CFBundleDisplayName: "$(BUNDLE_DISPLAY_NAME)"
+        CFBundleShortVersionString: "$(MARKETING_VERSION)"
+        NSExtension:
+          NSExtensionPointIdentifier: ${point_identifier}
+          NSExtensionPrincipalClass: $(PRODUCT_MODULE_NAME).${principal_class}
+
 targets:
   ProtonMail:
     type: application
@@ -179,6 +209,7 @@ targets:
           - AccountManager
           - AccountPassword
       - package: Scrypt
+      - target: ShareExtension
       - package: SwiftUIIntrospect
     preBuildScripts:
       - name: swift-format
@@ -227,31 +258,40 @@ targets:
     scheme: ProtonMailUITest
 
   NotificationService:
-    type: app-extension
-    platform: iOS
+    templates:
+      - Extension
+    templateAttributes:
+      bundle_identifier: ch.protonmail.protonmail.notifications
+      principal_class: NotificationService
+      point_identifier: com.apple.usernotifications.service
+      release_provisioning_profile: "Mail - Notification Service Distribution"
     dependencies:
       - package: TestableNotificationService
-    scheme: {}
-    sources:
-      - path: Modules/NotificationService/Sources
-    settings:
-      base:
-        CODE_SIGN_ENTITLEMENTS: "NotificationService.entitlements"
-        CODE_SIGN_IDENTITY: "iPhone Distribution: Proton AG (2SB5Z68H26)"
-        PRODUCT_BUNDLE_IDENTIFIER: "ch.protonmail.protonmail.notifications"
-        PROVISIONING_PROFILE_SPECIFIER: "Mail - Notification Service Distribution"
-      configs:
-        Debug:
-          CODE_SIGN_IDENTITY: "Apple Development"
-          CODE_SIGN_STYLE: Automatic
-          PROVISIONING_PROFILE_SPECIFIER: ""
+
+  ShareExtension:
+    templates:
+      - Extension
+    templateAttributes:
+      bundle_identifier: ch.protonmail.protonmail.Share
+      principal_class: ShareViewController
+      point_identifier: com.apple.share-services
+      release_provisioning_profile: "Protonmail share release"
+    dependencies:
+      - package: TestableShareExtension
     info:
-      path: Modules/NotificationService/Sources/SupportingFiles/Info.plist
       properties:
-        CFBundleDisplayName: "$(BUNDLE_DISPLAY_NAME)"
         NSExtension:
-          NSExtensionPointIdentifier: 'com.apple.usernotifications.service'
-          NSExtensionPrincipalClass: '$(PRODUCT_MODULE_NAME).NotificationService'
+          NSExtensionAttributes:
+            NSExtensionActivationRule: >
+              SUBQUERY (
+                extensionItems,
+                $extensionItem,
+                SUBQUERY (
+                    $extensionItem.attachments,
+                    $attachment,
+                    ANY $attachment.registeredTypeIdentifiers UTI-CONFORMS-TO "public.data"
+                ).@count > 0
+              ).@count > 0
 
 schemes:
   ProtonMailUITest: