smart_printer/smart_printer/PaywallView.swift

import Cocoa
import StoreKit

// MARK: - Plan Model

enum PaywallPlan: CaseIterable {
    case monthly
    case yearly
    case lifetime

    var productID: String {
        switch self {
        case .monthly: StoreProductID.monthly
        case .yearly: StoreProductID.yearly
        case .lifetime: StoreProductID.lifetime
        }
    }

    var title: String {
        switch self {
        case .monthly: "Monthly"
        case .yearly: "Yearly"
        case .lifetime: "Lifetime"
        }
    }

    var subtitle: String {
        switch self {
        case .monthly: "$4.99 / month, cancel anytime"
        case .yearly: "Eligible new subscribers get 7 days free, then $29.99 / year"
        case .lifetime: "$99.99 once, lifetime access"
        }
    }

    var price: String {
        switch self {
        case .monthly: "$4.99"
        case .yearly: "$29.99"
        case .lifetime: "$99.99"
        }
    }

    var ctaTitle: String {
        switch self {
        case .monthly: "Subscribe for $4.99 / Month"
        case .yearly: "Start 7-Day Free Trial"
        case .lifetime: "Buy Lifetime Access"
        }
    }

    func localizedPrice(from product: Product?) -> String {
        product?.displayPrice ?? price
    }

    func localizedSubtitle(from product: Product?) -> String {
        guard let product else { return subtitle }

        switch self {
        case .monthly:
            return "\(product.displayPrice) / month, cancel anytime"
        case .yearly:
            if product.subscription?.introductoryOffer != nil {
                return "Eligible new subscribers get 7 days free, then \(product.displayPrice) / year"
            }
            return "\(product.displayPrice) / year, cancel anytime"
        case .lifetime:
            return "\(product.displayPrice) once, lifetime access"
        }
    }

    func localizedCTATitle(from product: Product?) -> String {
        guard let product else { return ctaTitle }

        switch self {
        case .monthly:
            return "Subscribe for \(product.displayPrice) / Month"
        case .yearly:
            if product.subscription?.introductoryOffer != nil {
                return "Start 7-Day Free Trial"
            }
            return "Subscribe for \(product.displayPrice) / Year"
        case .lifetime:
            return "Buy Lifetime Access for \(product.displayPrice)"
        }
    }
}

// MARK: - StoreKit

enum StoreProductID {
    static let monthly = "MQL-DEV.smart-printer.premium.monthly"
    static let yearly = "MQL-DEV.smart-printer.premium.yearly"
    static let lifetime = "MQL-DEV.smart-printer.premium.lifetime"

    static let all: Set<String> = [monthly, yearly, lifetime]
}

enum StoreError: LocalizedError {
    case productNotFound
    case failedVerification

    var errorDescription: String? {
        switch self {
        case .productNotFound:
            "The selected plan is not available right now. Please try again later."
        case .failedVerification:
            "We couldn't verify your purchase. Please contact support."
        }
    }
}

@MainActor
final class StoreManager {
    static let shared = StoreManager()

    private(set) var products: [Product] = []
    private(set) var isPremium = false
    var isPro: Bool { isPremium }
    private(set) var isLoadingProducts = false
    private(set) var isPurchasing = false

    private var transactionListener: Task<Void, Never>?
    private var hasStarted = false

    private init() {}

    func start() {
        guard !hasStarted else { return }
        hasStarted = true

        transactionListener = Task { [weak self] in
            for await update in Transaction.updates {
                await self?.handleTransactionUpdate(update)
            }
        }

        Task {
            await loadProducts()
            await refreshPremiumStatus()
        }
    }

    func product(for plan: PaywallPlan) -> Product? {
        products.first { $0.id == plan.productID }
    }

    func loadProducts() async {
        isLoadingProducts = true
        postStoreStateDidChange()
        defer {
            isLoadingProducts = false
            postStoreStateDidChange()
        }

        do {
            products = try await Product.products(for: StoreProductID.all)
                .sorted { lhs, rhs in
                    productSortOrder(for: lhs.id) < productSortOrder(for: rhs.id)
                }
            NotificationCenter.default.post(name: .storeProductsDidUpdate, object: nil)
        } catch {
            NSLog("Failed to load products: \(error.localizedDescription)")
        }
    }

    @discardableResult
    func purchase(plan: PaywallPlan) async throws -> Bool {
        if products.isEmpty {
            await loadProducts()
        }

        guard let product = product(for: plan) else {
            throw StoreError.productNotFound
        }

        isPurchasing = true
        postStoreStateDidChange()
        defer {
            isPurchasing = false
            postStoreStateDidChange()
        }

        let result = try await product.purchase()

        switch result {
        case .success(let verification):
            let transaction = try checkVerified(verification)
            await transaction.finish()
            await refreshPremiumStatus()
            return isPremium
        case .userCancelled, .pending:
            return false
        @unknown default:
            return false
        }
    }

    @discardableResult
    func restorePurchases() async throws -> Bool {
        isPurchasing = true
        postStoreStateDidChange()
        defer {
            isPurchasing = false
            postStoreStateDidChange()
        }

        try await AppStore.sync()
        await refreshPremiumStatus()
        return isPremium
    }

    func showAlert(title: String, message: String, on window: NSWindow?) {
        let alert = NSAlert()
        alert.messageText = title
        alert.informativeText = message
        alert.alertStyle = .informational
        alert.addButton(withTitle: "OK")
        if let window {
            alert.beginSheetModal(for: window)
        } else {
            alert.runModal()
        }
    }

    func showManageSubscriptions() {
        guard let url = URL(string: "https://apps.apple.com/account/subscriptions") else { return }
        NSWorkspace.shared.open(url)
    }

    func showPurchaseError(_ error: Error, on window: NSWindow?) {
        if let storeError = error as? StoreError {
            showAlert(title: "Purchase Failed", message: storeError.localizedDescription, on: window)
            return
        }

        if let storeKitError = error as? StoreKitError, case .userCancelled = storeKitError {
            return
        }

        showAlert(title: "Purchase Failed", message: error.localizedDescription, on: window)
    }

    private func handleTransactionUpdate(_ update: VerificationResult<Transaction>) async {
        do {
            let transaction = try checkVerified(update)
            await transaction.finish()
            await refreshPremiumStatus()
        } catch {
            NSLog("Transaction verification failed: \(error.localizedDescription)")
        }
    }

    func refreshPremiumStatus() async {
        let hasPremium = await hasActivePremiumAccess()
        let didChange = hasPremium != isPremium
        isPremium = hasPremium

        if didChange {
            NotificationCenter.default.post(name: .premiumStatusDidChange, object: nil)
        }
        postStoreStateDidChange()
    }

    private func hasActivePremiumAccess() async -> Bool {
        if await hasEntitlementFromCurrentEntitlements() {
            return true
        }
        if await hasEntitlementFromLatestTransactions() {
            return true
        }
        if await hasEntitlementFromSubscriptionStatus() {
            return true
        }
        return false
    }

    private func hasEntitlementFromCurrentEntitlements() async -> Bool {
        for await result in Transaction.currentEntitlements {
            guard let transaction = try? checkVerified(result) else { continue }
            if isActivePremiumTransaction(transaction) {
                return true
            }
        }
        return false
    }

    private func hasEntitlementFromLatestTransactions() async -> Bool {
        for productID in StoreProductID.all {
            guard let result = await Transaction.latest(for: productID),
                  let transaction = try? checkVerified(result) else { continue }
            if isActivePremiumTransaction(transaction) {
                return true
            }
        }
        return false
    }

    private func hasEntitlementFromSubscriptionStatus() async -> Bool {
        for product in products where product.subscription != nil {
            guard StoreProductID.all.contains(product.id) else { continue }
            guard let statuses = try? await product.subscription?.status else { continue }
            for status in statuses {
                switch status.state {
                case .subscribed, .inGracePeriod, .inBillingRetryPeriod:
                    return true
                default:
                    continue
                }
            }
        }
        return false
    }

    private func isActivePremiumTransaction(_ transaction: Transaction) -> Bool {
        guard StoreProductID.all.contains(transaction.productID) else { return false }
        guard transaction.revocationDate == nil else { return false }
        if let expirationDate = transaction.expirationDate {
            return expirationDate > Date()
        }
        return true
    }

    private func checkVerified<T>(_ result: VerificationResult<T>) throws -> T {
        switch result {
        case .unverified:
            throw StoreError.failedVerification
        case .verified(let safe):
            return safe
        }
    }

    private func productSortOrder(for productID: String) -> Int {
        switch productID {
        case StoreProductID.monthly: 0
        case StoreProductID.yearly: 1
        case StoreProductID.lifetime: 2
        default: 99
        }
    }

    private func postStoreStateDidChange() {
        NotificationCenter.default.post(name: .storeStateDidChange, object: nil)
    }
}

extension Notification.Name {
    static let premiumStatusDidChange = Notification.Name("premiumStatusDidChange")
    static let storeProductsDidUpdate = Notification.Name("storeProductsDidUpdate")
    static let storeStateDidChange = Notification.Name("storeStateDidChange")
}

// MARK: - Left Panel

private final class PaywallLeftPanelView: NSView, AppearanceRefreshable {
    private let gradientLayer = CAGradientLayer()

    override init(frame frameRect: NSRect) {
        super.init(frame: frameRect)
        wantsLayer = true
        gradientLayer.startPoint = CGPoint(x: 0.5, y: 1)
        gradientLayer.endPoint = CGPoint(x: 0.5, y: 0)
        layer?.insertSublayer(gradientLayer, at: 0)
        refreshAppearance()
    }

    func refreshAppearance() {
        gradientLayer.colors = AppTheme.paywallLeftGradientColors.map(\.cgColor)
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) { nil }

    override func layout() {
        super.layout()
        gradientLayer.frame = bounds
        let mask = CAShapeLayer()
        mask.path = CGPath(
            roundedRect: bounds,
            cornerWidth: 20,
            cornerHeight: 20,
            transform: nil
        )
        layer?.mask = mask
    }
}

// MARK: - Badge

private final class PaywallBadgeView: NSView {
    init(text: String, iconName: String, background: NSColor, foreground: NSColor) {
        super.init(frame: .zero)
        translatesAutoresizingMaskIntoConstraints = false
        wantsLayer = true
        layer?.backgroundColor = background.cgColor
        layer?.cornerRadius = 10
        layer?.masksToBounds = true

        let icon = NSImageView()
        icon.translatesAutoresizingMaskIntoConstraints = false
        if let image = NSImage(systemSymbolName: iconName, accessibilityDescription: nil) {
            let config = NSImage.SymbolConfiguration(pointSize: 9, weight: .semibold)
            icon.image = image.withSymbolConfiguration(config)
        }
        icon.contentTintColor = foreground

        let label = NSTextField(labelWithString: text)
        label.font = AppTheme.semiboldFont(size: 10)
        label.textColor = foreground
        label.translatesAutoresizingMaskIntoConstraints = false

        addSubview(icon)
        addSubview(label)

        NSLayoutConstraint.activate([
            heightAnchor.constraint(equalToConstant: 20),

            icon.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 8),
            icon.centerYAnchor.constraint(equalTo: centerYAnchor),
            icon.widthAnchor.constraint(equalToConstant: 12),
            icon.heightAnchor.constraint(equalToConstant: 12),

            label.leadingAnchor.constraint(equalTo: icon.trailingAnchor, constant: 4),
            label.centerYAnchor.constraint(equalTo: centerYAnchor),
            label.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -8),
        ])
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) { nil }
}

// MARK: - Feature Row

private final class PaywallFeatureRow: NSView, AppearanceRefreshable {
    private let label: NSTextField

    init(text: String) {
        label = NSTextField.themeLabel(text, style: .primary, font: AppTheme.regularFont(size: 14))
        super.init(frame: .zero)
        translatesAutoresizingMaskIntoConstraints = false

        let checkContainer = NSView()
        checkContainer.translatesAutoresizingMaskIntoConstraints = false
        checkContainer.wantsLayer = true
        checkContainer.layer?.backgroundColor = AppTheme.green.cgColor
        checkContainer.layer?.cornerRadius = 10
        checkContainer.layer?.masksToBounds = true

        let checkIcon = NSImageView()
        checkIcon.translatesAutoresizingMaskIntoConstraints = false
        if let image = NSImage(systemSymbolName: "checkmark", accessibilityDescription: nil) {
            let config = NSImage.SymbolConfiguration(pointSize: 9, weight: .bold)
            checkIcon.image = image.withSymbolConfiguration(config)
        }
        checkIcon.contentTintColor = .white

        label.translatesAutoresizingMaskIntoConstraints = false

        addSubview(checkContainer)
        checkContainer.addSubview(checkIcon)
        addSubview(label)

        NSLayoutConstraint.activate([
            heightAnchor.constraint(equalToConstant: 28),

            checkContainer.leadingAnchor.constraint(equalTo: leadingAnchor),
            checkContainer.centerYAnchor.constraint(equalTo: centerYAnchor),
            checkContainer.widthAnchor.constraint(equalToConstant: 20),
            checkContainer.heightAnchor.constraint(equalToConstant: 20),

            checkIcon.centerXAnchor.constraint(equalTo: checkContainer.centerXAnchor),
            checkIcon.centerYAnchor.constraint(equalTo: checkContainer.centerYAnchor),
            checkIcon.widthAnchor.constraint(equalToConstant: 12),
            checkIcon.heightAnchor.constraint(equalToConstant: 12),

            label.leadingAnchor.constraint(equalTo: checkContainer.trailingAnchor, constant: 12),
            label.centerYAnchor.constraint(equalTo: centerYAnchor),
            label.trailingAnchor.constraint(equalTo: trailingAnchor),
        ])
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) { nil }

    func refreshAppearance() {
        label.refreshThemeLabelColor()
    }
}

// MARK: - Plan Card

private final class PaywallPlanCard: NSControl, AppearanceRefreshable {
    var onSelect: (() -> Void)?

    private let plan: PaywallPlan
    private let titleLabel = NSTextField(labelWithString: "")
    private let subtitleLabel = NSTextField(labelWithString: "")
    private let priceLabel = NSTextField(labelWithString: "")
    private var badgeView: PaywallBadgeView?
    private var hoverTracker: HoverTracker?
    private var isHovered = false

    var isChosen: Bool = false {
        didSet { updateAppearance() }
    }

    init(plan: PaywallPlan) {
        self.plan = plan
        super.init(frame: .zero)
        translatesAutoresizingMaskIntoConstraints = false
        wantsLayer = true
        layer?.cornerRadius = 12
        layer?.masksToBounds = false

        titleLabel.stringValue = plan.title
        titleLabel.font = AppTheme.semiboldFont(size: 15)
        titleLabel.translatesAutoresizingMaskIntoConstraints = false

        subtitleLabel.stringValue = plan.subtitle
        subtitleLabel.font = AppTheme.regularFont(size: 11)
        subtitleLabel.themeLabelStyle = .secondary
        subtitleLabel.textColor = AppTheme.textSecondary
        subtitleLabel.translatesAutoresizingMaskIntoConstraints = false

        priceLabel.stringValue = plan.price
        priceLabel.font = AppTheme.semiboldFont(size: 15)
        priceLabel.alignment = .right
        priceLabel.translatesAutoresizingMaskIntoConstraints = false

        addSubview(titleLabel)
        addSubview(subtitleLabel)
        addSubview(priceLabel)

        NSLayoutConstraint.activate([
            heightAnchor.constraint(equalToConstant: 86),

            titleLabel.leadingAnchor.constraint(equalTo: leadingAnchor, constant: 16),
            titleLabel.topAnchor.constraint(equalTo: topAnchor, constant: 24),

            subtitleLabel.leadingAnchor.constraint(equalTo: titleLabel.leadingAnchor),
            subtitleLabel.topAnchor.constraint(equalTo: titleLabel.bottomAnchor, constant: 3),
            subtitleLabel.trailingAnchor.constraint(lessThanOrEqualTo: priceLabel.leadingAnchor, constant: -12),

            priceLabel.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -16),
            priceLabel.centerYAnchor.constraint(equalTo: centerYAnchor),
        ])

        if plan == .yearly {
            let badge = PaywallBadgeView(
                text: "7 Days Free Trial",
                iconName: "calendar",
                background: AppTheme.paywallPink,
                foreground: AppTheme.paywallPinkText
            )
            badgeView = badge
            addSubview(badge)
            NSLayoutConstraint.activate([
                badge.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -12),
                badge.topAnchor.constraint(equalTo: topAnchor, constant: 8),
            ])
        } else if plan == .lifetime {
            let badge = PaywallBadgeView(
                text: "Best Value",
                iconName: "star.fill",
                background: AppTheme.paywallGold,
                foreground: AppTheme.paywallGoldText
            )
            badgeView = badge
            addSubview(badge)
            NSLayoutConstraint.activate([
                badge.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -12),
                badge.topAnchor.constraint(equalTo: topAnchor, constant: 8),
            ])
        }

        applyCardShadow()
        updateAppearance()

        hoverTracker = HoverTracker(view: self) { [weak self] hovering in
            self?.setHovered(hovering)
        }
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) { nil }

    func updateDisplay(product: Product?) {
        subtitleLabel.stringValue = plan.localizedSubtitle(from: product)
        priceLabel.stringValue = plan.localizedPrice(from: product)
    }

    func refreshAppearance() {
        updateAppearance()
        subtitleLabel.refreshThemeLabelColor()
        if isHovered {
            applyHoverLift(true)
        }
    }

    private func setHovered(_ hovering: Bool) {
        isHovered = hovering
        applyHoverLift(hovering)
        updateAppearance()
    }

    private func updateAppearance() {
        let titleColor = isChosen && plan == .yearly ? AppTheme.green : AppTheme.paywallAccent
        titleLabel.textColor = titleColor
        priceLabel.textColor = titleColor

        layer?.backgroundColor = AppTheme.paywallTrustBackground.cgColor

        if isChosen {
            layer?.borderWidth = 2
            layer?.borderColor = AppTheme.green.cgColor
        } else if isHovered {
            layer?.borderWidth = 2
            let hoverBorder = AppTheme.paywallBorder.blended(withFraction: 0.35, of: AppTheme.paywallAccent)
                ?? AppTheme.paywallBorder
            layer?.borderColor = hoverBorder.cgColor
        } else {
            layer?.borderWidth = 1.5
            layer?.borderColor = AppTheme.paywallBorder.cgColor
        }
    }

    override func mouseUp(with event: NSEvent) {
        guard bounds.contains(convert(event.locationInWindow, from: nil)) else { return }
        onSelect?()
    }

    override func resetCursorRects() {
        addCursorRect(bounds, cursor: .pointingHand)
    }
}

// MARK: - Footer Link

private final class PaywallFooterLink: NSButton, AppearanceRefreshable {
    private var hoverTracker: HoverTracker?
    private var isHovered = false

    init(title: String) {
        super.init(frame: .zero)
        updateTitle(title)
        isBordered = false
        bezelStyle = .inline
        font = AppTheme.regularFont(size: 11)
        translatesAutoresizingMaskIntoConstraints = false
        refreshAppearance()

        hoverTracker = HoverTracker(view: self) { [weak self] hovering in
            self?.isHovered = hovering
            self?.refreshAppearance()
        }
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) { nil }

    func updateTitle(_ title: String) {
        self.title = title
        invalidateIntrinsicContentSize()
        needsDisplay = true
    }

    func refreshAppearance() {
        contentTintColor = isHovered ? AppTheme.textPrimary : AppTheme.textSecondary
    }

    override func resetCursorRects() {
        addCursorRect(bounds, cursor: .pointingHand)
    }
}

// MARK: - Footer Trust Item

private final class PaywallTrustItemView: NSView, AppearanceRefreshable {
    private let iconContainer = NSView()
    private let icon = NSImageView()
    private let titleLabel: NSTextField
    private let subtitleLabel: NSTextField

    init(iconName: String, title: String, subtitle: String) {
        titleLabel = NSTextField.themeLabel(title, style: .primary, font: AppTheme.semiboldFont(size: 11))
        subtitleLabel = NSTextField.themeLabel(subtitle, style: .secondary, font: AppTheme.regularFont(size: 9))
        super.init(frame: .zero)
        translatesAutoresizingMaskIntoConstraints = false

        iconContainer.translatesAutoresizingMaskIntoConstraints = false
        iconContainer.wantsLayer = true
        iconContainer.layer?.cornerRadius = 10
        iconContainer.layer?.masksToBounds = true

        icon.translatesAutoresizingMaskIntoConstraints = false
        if let image = NSImage(systemSymbolName: iconName, accessibilityDescription: nil) {
            let config = NSImage.SymbolConfiguration(pointSize: 11, weight: .semibold)
            icon.image = image.withSymbolConfiguration(config)
        }

        titleLabel.lineBreakMode = .byTruncatingTail
        titleLabel.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
        titleLabel.translatesAutoresizingMaskIntoConstraints = false

        subtitleLabel.lineBreakMode = .byTruncatingTail
        subtitleLabel.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
        subtitleLabel.translatesAutoresizingMaskIntoConstraints = false

        addSubview(iconContainer)
        iconContainer.addSubview(icon)
        addSubview(titleLabel)
        addSubview(subtitleLabel)

        NSLayoutConstraint.activate([
            iconContainer.leadingAnchor.constraint(equalTo: leadingAnchor),
            iconContainer.topAnchor.constraint(equalTo: topAnchor),
            iconContainer.widthAnchor.constraint(equalToConstant: 20),
            iconContainer.heightAnchor.constraint(equalToConstant: 20),

            icon.centerXAnchor.constraint(equalTo: iconContainer.centerXAnchor),
            icon.centerYAnchor.constraint(equalTo: iconContainer.centerYAnchor),
            icon.widthAnchor.constraint(equalToConstant: 12),
            icon.heightAnchor.constraint(equalToConstant: 12),

            titleLabel.leadingAnchor.constraint(equalTo: iconContainer.trailingAnchor, constant: 8),
            titleLabel.topAnchor.constraint(equalTo: topAnchor, constant: 1),
            titleLabel.trailingAnchor.constraint(equalTo: trailingAnchor),

            subtitleLabel.leadingAnchor.constraint(equalTo: titleLabel.leadingAnchor),
            subtitleLabel.topAnchor.constraint(equalTo: titleLabel.bottomAnchor, constant: 2),
            subtitleLabel.trailingAnchor.constraint(equalTo: trailingAnchor),
            subtitleLabel.bottomAnchor.constraint(equalTo: bottomAnchor),
        ])

        setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
        setContentHuggingPriority(.defaultLow, for: .horizontal)
        refreshAppearance()
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) { nil }

    func refreshAppearance() {
        iconContainer.layer?.backgroundColor = AppTheme.paywallTrustIconBackground.cgColor
        icon.contentTintColor = AppTheme.paywallIconAccent
        titleLabel.refreshThemeLabelColor()
        subtitleLabel.refreshThemeLabelColor()
    }
}

// MARK: - Close Button

private final class PaywallCloseButton: NSButton, AppearanceRefreshable {
    private var hoverTracker: HoverTracker?
    private var isHovered = false

    init() {
        super.init(frame: .zero)
        isBordered = false
        bezelStyle = .inline
        translatesAutoresizingMaskIntoConstraints = false
        wantsLayer = true
        layer?.cornerRadius = 15
        layer?.borderWidth = 1.5
        if let image = NSImage(systemSymbolName: "xmark", accessibilityDescription: "Close") {
            let config = NSImage.SymbolConfiguration(pointSize: 12, weight: .semibold)
            self.image = image.withSymbolConfiguration(config)
        }
        refreshAppearance()

        hoverTracker = HoverTracker(view: self) { [weak self] hovering in
            self?.setHovered(hovering)
        }
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) { nil }

    func refreshAppearance() {
        updateAppearance()
    }

    private func setHovered(_ hovering: Bool) {
        isHovered = hovering
        animateHover {
            updateAppearance()
            layer?.transform = hovering
                ? CATransform3DMakeScale(1.06, 1.06, 1)
                : CATransform3DIdentity
        }
    }

    private func updateAppearance() {
        if isHovered {
            layer?.backgroundColor = AppTheme.elevatedBackground.cgColor
            layer?.borderColor = AppTheme.paywallAccent.withAlphaComponent(0.45).cgColor
            contentTintColor = AppTheme.textPrimary
        } else {
            layer?.backgroundColor = AppTheme.paywallTrustBackground.cgColor
            layer?.borderColor = AppTheme.paywallBorder.cgColor
            contentTintColor = AppTheme.textSecondary
        }
    }

    override func resetCursorRects() {
        addCursorRect(bounds, cursor: .pointingHand)
    }
}

// MARK: - CTA Button

private final class PaywallCTAButton: NSButton, AppearanceRefreshable {
    private var hoverTracker: HoverTracker?

    init() {
        super.init(frame: .zero)
        isBordered = false
        wantsLayer = true
        layer?.cornerRadius = 12
        font = AppTheme.semiboldFont(size: 15)
        translatesAutoresizingMaskIntoConstraints = false
        refreshAppearance()

        hoverTracker = HoverTracker(view: self) { [weak self] hovering in
            self?.setHovered(hovering)
        }
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) { nil }

    func refreshAppearance() {
        layer?.backgroundColor = AppTheme.paywallCTABackground.cgColor
        contentTintColor = AppTheme.paywallCTAForeground
    }

    private func setHovered(_ hovering: Bool) {
        let base = AppTheme.paywallCTABackground
        let color = hovering ? base.blended(withFraction: 0.12, of: .black) ?? base : base
        animateHover {
            layer?.backgroundColor = color.cgColor
            layer?.transform = hovering
                ? CATransform3DMakeScale(1.02, 1.02, 1)
                : CATransform3DIdentity
        }
    }

    override func resetCursorRects() {
        addCursorRect(bounds, cursor: .pointingHand)
    }
}

// MARK: - Main Paywall Card

final class PaywallView: NSView, AppearanceRefreshable {
    var onClose: (() -> Void)?
    var onPurchaseSucceeded: (() -> Void)?

    private var selectedPlan: PaywallPlan = .yearly
    private var planCards: [PaywallPlan: PaywallPlanCard] = [:]
    private let ctaButton = PaywallCTAButton()
    private let continueFreePlanLink = PaywallFooterLink(title: "Continue with free plan")
    private let manageSubscriptionLink = PaywallFooterLink(title: "Manage Subscription")
    private let premiumCloseButton = PaywallCloseButton()
    private var primaryFooterLinkCell: NSView?
    private var leftPanelTitle: NSTextField!
    private var rightTitle: NSTextField!
    private var rightSubtitle: NSTextField!
    private var trustStack: NSStackView!
    private var storeObservers: [NSObjectProtocol] = []

    init() {
        super.init(frame: .zero)
        translatesAutoresizingMaskIntoConstraints = false
        wantsLayer = true
        layer?.cornerRadius = 0
        setup()
        observeStoreUpdates()
        refreshProductDisplay()
        refreshAppearance()
    }

    deinit {
        storeObservers.forEach { NotificationCenter.default.removeObserver($0) }
    }

    private func observeStoreUpdates() {
        let center = NotificationCenter.default
        storeObservers = [
            center.addObserver(forName: .storeProductsDidUpdate, object: nil, queue: .main) { [weak self] _ in
                self?.refreshProductDisplay()
            },
            center.addObserver(forName: .storeStateDidChange, object: nil, queue: .main) { [weak self] _ in
                self?.refreshPurchaseState()
            },
            center.addObserver(forName: .premiumStatusDidChange, object: nil, queue: .main) { [weak self] _ in
                self?.refreshPurchaseState()
            },
        ]
    }

    private func refreshProductDisplay() {
        let store = StoreManager.shared
        for (plan, card) in planCards {
            card.updateDisplay(product: store.product(for: plan))
        }
        ctaButton.title = selectedPlan.localizedCTATitle(from: store.product(for: selectedPlan))
        refreshPurchaseState()
    }

    private func refreshPurchaseState() {
        let store = StoreManager.shared
        let isBusy = store.isPurchasing || store.isLoadingProducts
        ctaButton.isEnabled = !isBusy
        ctaButton.alphaValue = isBusy ? 0.65 : 1
        refreshPrimaryFooterLink()
    }

    private func refreshPrimaryFooterLink() {
        let isPro = StoreManager.shared.isPro
        continueFreePlanLink.isHidden = isPro
        manageSubscriptionLink.isHidden = !isPro
        premiumCloseButton.isHidden = !isPro
        primaryFooterLinkCell?.needsLayout = true
        primaryFooterLinkCell?.layoutSubtreeIfNeeded()
    }

    func refreshStoreState() {
        refreshProductDisplay()
    }

    func refreshAppearance() {
        layer?.backgroundColor = AppTheme.paywallBackground.cgColor
        leftPanelTitle?.refreshThemeLabelColor()
        rightTitle?.refreshThemeLabelColor()
        rightSubtitle?.refreshThemeLabelColor()
        trustStack?.layer?.backgroundColor = AppTheme.paywallTrustBackground.cgColor
        trustStack?.layer?.borderColor = AppTheme.paywallBorder.cgColor
        ctaButton.refreshAppearance()
        subviews.forEach { $0.refreshAppearanceRecursively() }
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) { nil }

    private func setup() {
        let leftPanel = makeLeftPanel()
        let rightPanel = makeRightPanel()

        premiumCloseButton.target = self
        premiumCloseButton.action = #selector(premiumCloseTapped)
        premiumCloseButton.isHidden = true

        addSubview(leftPanel)
        addSubview(rightPanel)
        addSubview(premiumCloseButton)

        NSLayoutConstraint.activate([
            leftPanel.leadingAnchor.constraint(equalTo: leadingAnchor),
            leftPanel.topAnchor.constraint(equalTo: topAnchor),
            leftPanel.bottomAnchor.constraint(equalTo: bottomAnchor),
            leftPanel.widthAnchor.constraint(equalToConstant: 320),

            rightPanel.leadingAnchor.constraint(equalTo: leftPanel.trailingAnchor),
            rightPanel.trailingAnchor.constraint(equalTo: trailingAnchor),
            rightPanel.topAnchor.constraint(equalTo: topAnchor),
            rightPanel.bottomAnchor.constraint(equalTo: bottomAnchor),

            premiumCloseButton.topAnchor.constraint(equalTo: topAnchor, constant: 16),
            premiumCloseButton.trailingAnchor.constraint(equalTo: trailingAnchor, constant: -16),
            premiumCloseButton.widthAnchor.constraint(equalToConstant: 30),
            premiumCloseButton.heightAnchor.constraint(equalToConstant: 30),
        ])
    }

    private func makeLeftPanel() -> NSView {
        let panel = PaywallLeftPanelView()
        panel.translatesAutoresizingMaskIntoConstraints = false

        let title = NSTextField.themeLabel(
            "Unlock Your Full\nPrinting Potential",
            style: .primary,
            font: AppTheme.semiboldFont(size: 22)
        )
        title.maximumNumberOfLines = 2
        title.translatesAutoresizingMaskIntoConstraints = false
        leftPanelTitle = title

        let featuresStack = NSStackView()
        featuresStack.orientation = .vertical
        featuresStack.spacing = 6
        featuresStack.alignment = .leading
        featuresStack.translatesAutoresizingMaskIntoConstraints = false

        let features = [
            "Unlimited high-quality scans",
            "Advanced OCR technology",
            "Direct cloud printing",
            "Ad-free experience",
            "Priority support",
            "Secure storage",
        ]
        for feature in features {
            featuresStack.addArrangedSubview(PaywallFeatureRow(text: feature))
        }

        panel.addSubview(title)
        panel.addSubview(featuresStack)

        NSLayoutConstraint.activate([
            title.leadingAnchor.constraint(equalTo: panel.leadingAnchor, constant: 28),
            title.trailingAnchor.constraint(equalTo: panel.trailingAnchor, constant: -20),
            title.topAnchor.constraint(equalTo: panel.topAnchor, constant: 48),

            featuresStack.leadingAnchor.constraint(equalTo: title.leadingAnchor),
            featuresStack.trailingAnchor.constraint(equalTo: panel.trailingAnchor, constant: -20),
            featuresStack.topAnchor.constraint(equalTo: title.bottomAnchor, constant: 28),
        ])

        return panel
    }

    private func makeRightPanel() -> NSView {
        let panel = NSView()
        panel.translatesAutoresizingMaskIntoConstraints = false

        let title = NSTextField.themeLabel("Go Premium", style: .primary, font: AppTheme.semiboldFont(size: 26))
        title.alignment = .center
        title.translatesAutoresizingMaskIntoConstraints = false
        rightTitle = title

        let subtitle = NSTextField.themeLabel(
            "Experience professional quality printing and scanning without limits.",
            style: .secondary,
            font: AppTheme.regularFont(size: 13)
        )
        subtitle.alignment = .center
        subtitle.maximumNumberOfLines = 2
        subtitle.translatesAutoresizingMaskIntoConstraints = false
        rightSubtitle = subtitle

        let plansStack = NSStackView()
        plansStack.orientation = .vertical
        plansStack.spacing = 12
        plansStack.translatesAutoresizingMaskIntoConstraints = false

        for plan in PaywallPlan.allCases {
            let card = PaywallPlanCard(plan: plan)
            card.isChosen = plan == selectedPlan
            card.onSelect = { [weak self] in self?.selectPlan(plan) }
            planCards[plan] = card
            plansStack.addArrangedSubview(card)
        }

        ctaButton.title = selectedPlan.localizedCTATitle(from: StoreManager.shared.product(for: selectedPlan))
        ctaButton.target = self
        ctaButton.action = #selector(purchaseTapped)
        ctaButton.translatesAutoresizingMaskIntoConstraints = false

        let trustRow = makeTrustRow()
        let footerLinks = makeFooterLinks()

        panel.addSubview(title)
        panel.addSubview(subtitle)
        panel.addSubview(plansStack)
        panel.addSubview(trustRow)
        panel.addSubview(ctaButton)
        panel.addSubview(footerLinks)

        NSLayoutConstraint.activate([
            title.leadingAnchor.constraint(equalTo: panel.leadingAnchor, constant: 28),
            title.topAnchor.constraint(equalTo: panel.topAnchor, constant: 40),
            title.trailingAnchor.constraint(equalTo: panel.trailingAnchor, constant: -28),

            subtitle.leadingAnchor.constraint(equalTo: title.leadingAnchor),
            subtitle.trailingAnchor.constraint(equalTo: panel.trailingAnchor, constant: -28),
            subtitle.topAnchor.constraint(equalTo: title.bottomAnchor, constant: 6),

            plansStack.leadingAnchor.constraint(equalTo: title.leadingAnchor),
            plansStack.trailingAnchor.constraint(equalTo: panel.trailingAnchor, constant: -28),
            plansStack.topAnchor.constraint(equalTo: subtitle.bottomAnchor, constant: 24),

            trustRow.leadingAnchor.constraint(equalTo: plansStack.leadingAnchor),
            trustRow.trailingAnchor.constraint(equalTo: plansStack.trailingAnchor),
            trustRow.topAnchor.constraint(equalTo: plansStack.bottomAnchor, constant: 18),

            ctaButton.leadingAnchor.constraint(equalTo: plansStack.leadingAnchor),
            ctaButton.trailingAnchor.constraint(equalTo: plansStack.trailingAnchor),
            ctaButton.topAnchor.constraint(equalTo: trustRow.bottomAnchor, constant: 16),
            ctaButton.heightAnchor.constraint(equalToConstant: 48),
            ctaButton.bottomAnchor.constraint(lessThanOrEqualTo: footerLinks.topAnchor, constant: -14),

            footerLinks.leadingAnchor.constraint(equalTo: panel.leadingAnchor, constant: 28),
            footerLinks.trailingAnchor.constraint(equalTo: panel.trailingAnchor, constant: -28),
            footerLinks.bottomAnchor.constraint(equalTo: panel.bottomAnchor, constant: -20),
        ])

        return panel
    }

    private func makeTrustRow() -> NSView {
        let securePayments = PaywallTrustItemView(
            iconName: "shield.fill",
            title: "Secure Payments",
            subtitle: "Your payment is 100% secure"
        )
        let cancelAnytime = PaywallTrustItemView(
            iconName: "arrow.counterclockwise",
            title: "Cancel Anytime",
            subtitle: "No commitment, cancel anytime."
        )
        let support = PaywallTrustItemView(
            iconName: "headphones",
            title: "24/7 Support",
            subtitle: "We're here to help you anytime."
        )
        let privacyFirst = PaywallTrustItemView(
            iconName: "lock.fill",
            title: "Privacy First",
            subtitle: "Your data is safe with us."
        )

        let trustStack = NSStackView(views: [securePayments, cancelAnytime, support, privacyFirst])
        trustStack.orientation = .horizontal
        trustStack.distribution = .fillEqually
        trustStack.spacing = 16
        trustStack.alignment = .top
        trustStack.translatesAutoresizingMaskIntoConstraints = false
        trustStack.wantsLayer = true
        trustStack.layer?.cornerRadius = 12
        trustStack.layer?.borderWidth = 1.5
        trustStack.layer?.masksToBounds = true
        trustStack.edgeInsets = NSEdgeInsets(top: 12, left: 14, bottom: 12, right: 14)
        trustStack.translatesAutoresizingMaskIntoConstraints = false
        self.trustStack = trustStack

        return trustStack
    }

    private func makeFooterLinks() -> NSView {
        let container = NSView()
        container.translatesAutoresizingMaskIntoConstraints = false

        continueFreePlanLink.target = self
        continueFreePlanLink.action = #selector(continueWithFreePlanTapped)
        manageSubscriptionLink.target = self
        manageSubscriptionLink.action = #selector(manageSubscriptionTapped)

        let primaryCell = makePrimaryFooterLinkCell()
        primaryFooterLinkCell = primaryCell
        refreshPrimaryFooterLink()

        let restoreLink = PaywallFooterLink(title: "Restore Purchase")
        restoreLink.target = self
        restoreLink.action = #selector(restoreTapped)

        let privacyLink = PaywallFooterLink(title: "Privacy Policy")
        let termsLink = PaywallFooterLink(title: "Terms of Service")
        let supportLink = PaywallFooterLink(title: "Support")

        let linkCells = [
            primaryCell,
            makeFooterLinkCell(link: restoreLink),
            makeFooterLinkCell(link: privacyLink),
            makeFooterLinkCell(link: termsLink),
            makeFooterLinkCell(link: supportLink),
        ]

        let linksStack = NSStackView(views: linkCells)
        linksStack.orientation = .horizontal
        linksStack.spacing = 0
        linksStack.alignment = .centerY
        linksStack.distribution = .fillEqually
        linksStack.translatesAutoresizingMaskIntoConstraints = false

        container.addSubview(linksStack)
        NSLayoutConstraint.activate([
            linksStack.leadingAnchor.constraint(equalTo: container.leadingAnchor),
            linksStack.trailingAnchor.constraint(equalTo: container.trailingAnchor),
            linksStack.topAnchor.constraint(equalTo: container.topAnchor),
            linksStack.bottomAnchor.constraint(equalTo: container.bottomAnchor),
        ])

        return container
    }

    private func makePrimaryFooterLinkCell() -> NSView {
        let cell = NSView()
        cell.translatesAutoresizingMaskIntoConstraints = false

        for link in [continueFreePlanLink, manageSubscriptionLink] {
            cell.addSubview(link)
            NSLayoutConstraint.activate([
                link.centerXAnchor.constraint(equalTo: cell.centerXAnchor),
                link.centerYAnchor.constraint(equalTo: cell.centerYAnchor),
                link.topAnchor.constraint(equalTo: cell.topAnchor),
                link.bottomAnchor.constraint(equalTo: cell.bottomAnchor),
            ])
        }

        return cell
    }

    private func makeFooterLinkCell(link: PaywallFooterLink) -> NSView {
        let cell = NSView()
        cell.translatesAutoresizingMaskIntoConstraints = false

        cell.addSubview(link)
        NSLayoutConstraint.activate([
            link.centerXAnchor.constraint(equalTo: cell.centerXAnchor),
            link.centerYAnchor.constraint(equalTo: cell.centerYAnchor),
            link.topAnchor.constraint(equalTo: cell.topAnchor),
            link.bottomAnchor.constraint(equalTo: cell.bottomAnchor),
        ])

        return cell
    }

    private func selectPlan(_ plan: PaywallPlan) {
        selectedPlan = plan
        for (key, card) in planCards {
            card.isChosen = key == plan
        }
        ctaButton.title = plan.localizedCTATitle(from: StoreManager.shared.product(for: plan))
    }

    @objc private func purchaseTapped() {
        Task { @MainActor in
            refreshPurchaseState()
            do {
                let succeeded = try await StoreManager.shared.purchase(plan: selectedPlan)
                refreshStoreState()
                if succeeded {
                    onPurchaseSucceeded?()
                }
            } catch {
                refreshPurchaseState()
                StoreManager.shared.showPurchaseError(error, on: window)
            }
        }
    }

    @objc private func restoreTapped() {
        Task { @MainActor in
            refreshPurchaseState()
            do {
                let restored = try await StoreManager.shared.restorePurchases()
                refreshStoreState()
                if restored {
                    onPurchaseSucceeded?()
                } else {
                    StoreManager.shared.showAlert(
                        title: "No Purchases Found",
                        message: "We couldn't find any previous purchases for this Apple ID.",
                        on: window
                    )
                }
            } catch {
                refreshPurchaseState()
                StoreManager.shared.showPurchaseError(error, on: window)
            }
        }
    }

    @objc private func continueWithFreePlanTapped() {
        onClose?()
    }

    @objc private func premiumCloseTapped() {
        onClose?()
    }

    @objc private func manageSubscriptionTapped() {
        StoreManager.shared.showManageSubscriptions()
    }
}

// MARK: - Overlay Presenter

final class PaywallOverlayView: NSView, AppearanceRefreshable {
    var onDismiss: (() -> Void)?

    private let paywallView: PaywallView
    private let blurView = NSVisualEffectView()
    private let backdrop = NSView()
    private let pattern = WavePatternView()

    init() {
        paywallView = PaywallView()
        super.init(frame: .zero)
        translatesAutoresizingMaskIntoConstraints = false
        setup()
        refreshAppearance()
    }

    func refreshAppearance() {
        backdrop.layer?.backgroundColor = AppTheme.paywallOverlayBackdrop.cgColor
        blurView.material = AppSettings.darkModeEnabled ? .hudWindow : .underWindowBackground
        pattern.refreshAppearance()
        paywallView.refreshAppearance()
    }

    func refreshStoreState() {
        paywallView.refreshStoreState()
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) { nil }

    private func setup() {
        blurView.translatesAutoresizingMaskIntoConstraints = false
        blurView.material = .underWindowBackground
        blurView.blendingMode = .withinWindow
        blurView.state = .active

        backdrop.translatesAutoresizingMaskIntoConstraints = false
        backdrop.wantsLayer = true
        backdrop.layer?.backgroundColor = NSColor(calibratedWhite: 0.15, alpha: 0.22).cgColor

        pattern.translatesAutoresizingMaskIntoConstraints = false
        pattern.alphaValue = 0.35

        paywallView.translatesAutoresizingMaskIntoConstraints = false
        paywallView.onClose = { [weak self] in self?.dismiss() }
        paywallView.onPurchaseSucceeded = { [weak self] in
            self?.paywallView.refreshStoreState()
        }

        addSubview(blurView)
        addSubview(backdrop)
        backdrop.addSubview(pattern)
        addSubview(paywallView)

        NSLayoutConstraint.activate([
            blurView.leadingAnchor.constraint(equalTo: leadingAnchor),
            blurView.trailingAnchor.constraint(equalTo: trailingAnchor),
            blurView.topAnchor.constraint(equalTo: topAnchor),
            blurView.bottomAnchor.constraint(equalTo: bottomAnchor),

            backdrop.leadingAnchor.constraint(equalTo: leadingAnchor),
            backdrop.trailingAnchor.constraint(equalTo: trailingAnchor),
            backdrop.topAnchor.constraint(equalTo: topAnchor),
            backdrop.bottomAnchor.constraint(equalTo: bottomAnchor),

            pattern.leadingAnchor.constraint(equalTo: backdrop.leadingAnchor),
            pattern.trailingAnchor.constraint(equalTo: backdrop.trailingAnchor),
            pattern.topAnchor.constraint(equalTo: backdrop.topAnchor),
            pattern.bottomAnchor.constraint(equalTo: backdrop.bottomAnchor),

            paywallView.leadingAnchor.constraint(equalTo: leadingAnchor),
            paywallView.trailingAnchor.constraint(equalTo: trailingAnchor),
            paywallView.topAnchor.constraint(equalTo: topAnchor),
            paywallView.bottomAnchor.constraint(equalTo: bottomAnchor),
        ])
    }

    func present(in parent: NSView) {
        guard superview == nil else { return }
        if let window = parent.window,
           let windowFrameView = window.contentView?.superview {
            windowFrameView.addSubview(self)
            NSLayoutConstraint.activate([
                leadingAnchor.constraint(equalTo: windowFrameView.leadingAnchor),
                trailingAnchor.constraint(equalTo: windowFrameView.trailingAnchor),
                topAnchor.constraint(equalTo: windowFrameView.topAnchor),
                bottomAnchor.constraint(equalTo: windowFrameView.bottomAnchor),
            ])
        } else {
            parent.addSubview(self)
            NSLayoutConstraint.activate([
                leadingAnchor.constraint(equalTo: parent.leadingAnchor),
                trailingAnchor.constraint(equalTo: parent.trailingAnchor),
                topAnchor.constraint(equalTo: parent.topAnchor),
                bottomAnchor.constraint(equalTo: parent.bottomAnchor),
            ])
        }
        alphaValue = 0
        Task { @MainActor in
            if StoreManager.shared.products.isEmpty {
                await StoreManager.shared.loadProducts()
            }
            await StoreManager.shared.refreshPremiumStatus()
            paywallView.refreshStoreState()
            alphaValue = 1
        }
    }

    func dismiss() {
        NSAnimationContext.runAnimationGroup({ context in
            context.duration = 0.15
            animator().alphaValue = 0
        }, completionHandler: { [weak self] in
            self?.removeFromSuperview()
            self?.onDismiss?()
        })
    }
}