iOS subscriptions and paywalls.
Stupidly simple.

Button("Subscribe for \(product.displayPrice)") {
    Task {
        do {
            let info = try await Payo.purchase("pro_monthly")
            print("Purchased! Expires: \(info.expirationDate ?? .now)")
        } catch let error as PayoError {
            switch error {
            case .userCancelled:
                break // user tapped Cancel — do nothing
            case .purchasePending:
                showAlert("Purchase pending approval.")
            default:
                showAlert("Error: \(error.localizedDescription)")
            }
        }
    }
}

// Default — blur + lock overlay
GroupBox("Premium Analytics") {
    AnalyticsChart()
}
.requiresAccess()

// Custom message and icon
GroupBox("Pro Features") {
    ProDashboard()
}
.requiresAccess("Pro Feature", icon: "star.fill")

// Fully custom overlay
GroupBox("Premium") {
    AnalyticsChart()
}
.requiresAccess {
    VStack {
        Image(systemName: "crown.fill")
            .font(.title)
        Text("Upgrade to Pro")
            .font(.headline)
    }
}

// Full-screen paywall — overlay is fully interactive
TabView {
    HomeView()
    SettingsView()
}
.requiresAccess {
    MyPaywallView() // buttons, links, etc. all work
}

// Gate behind a specific product ID (for multi-tier apps)
GroupBox("Premium Features") {
    PremiumDashboard()
}
.requiresAccess(group: "premium_monthly")

// Gate behind a tier (recommended for multi-tier)
GroupBox("Pro Features") {
    ProDashboard()
}
.requiresTier("pro")

struct ContentView: View {
    @ObservedObject var billing = Payo.state

    var body: some View {
        if billing.hasAccess {
            ProFeatureView()
        } else {
            PaywallView()
        }
    }
}

struct PaywallView: View {
    @State private var products: [ProductInfo] = []

    var body: some View {
        VStack(spacing: 16) {
            ForEach(products, id: \.id) { product in
                Button {
                    Task { try? await Payo.purchase(product.id) }
                } label: {
                    HStack {
                        VStack(alignment: .leading) {
                            Text(product.displayName).font(.headline)
                            Text(product.description).font(.caption)
                        }
                        Spacer()
                        Text(product.displayPrice)
                            .font(.headline)
                    }
                    .padding()
                    .background(.ultraThinMaterial)
                    .cornerRadius(12)
                }
            }
        }
        .task {
            products = await Payo.allProductInfo()
        }
    }
}

struct PaywallView: View {
    @State private var products: [ProductInfo] = []
    @State private var introEligible = false

    var body: some View {
        VStack {
            if introEligible, let offer = products.first?.introOffer {
                Text("Start your free \(offer.periodValue)-day trial!")
                    .font(.headline)
                    .foregroundStyle(.green)
            }

            ForEach(products, id: \.id) { product in
                Button(product.displayName) {
                    Task { try? await Payo.purchase(product.id) }
                }
            }
        }
        .task {
            products = await Payo.allProductInfo()
            introEligible = await Payo.isEligibleForIntroOffer()
        }
    }
}

Button("Restore Purchases") {
    Task {
        do {
            try await Payo.restorePurchases()
            // Access is automatically updated
        } catch {
            showAlert("Restore failed: \(error.localizedDescription)")
        }
    }
}

Button("Manage Subscription") {
    Task {
        try? await Payo.showManageSubscriptions()
    }
}

Button("Request Refund") {
    Task {
        let status = try? await Payo.beginRefundRequest("pro_monthly")
        if status == .success {
            // Apple is reviewing the request
        }
    }
}

struct FeatureView: View {
    var body: some View {
        VStack {
            // Gate features behind a tier
            // "pro" maps to pro_monthly + pro_annual in your dashboard
            if Payo.hasAccess("pro") {
                ProFeaturesView()
            }

            if Payo.hasAccess("premium") {
                PremiumFeaturesView()
            }

            if !Payo.hasAccess {
                PaywallView()
            }
        }
    }
}

// Or use the one-liner view modifier
GroupBox("Pro Analytics") {
    AnalyticsChart()
}
.requiresTier("pro")

struct SettingsView: View {
    @ObservedObject var billing = Payo.state
    @State private var subInfo: SubscriptionInfo?

    var body: some View {
        List {
            // Current plan (reactive)
            Section("Current Plan") {
                if let id = billing.activeProductIDs.first {
                    Text("Plan: \(id)")
                } else {
                    Text("No active subscription")
                }
            }

            // Subscription details
            if let info = subInfo {
                Section("Subscription Details") {
                    if let exp = info.expirationDate {
                        if info.willAutoRenew {
                            Text("Renews \(exp.formatted())")
                        } else {
                            Text("Ends \(exp.formatted())")
                                .foregroundStyle(.orange)
                        }
                    }

                    // Billing issue banner
                    if info.state == .inGracePeriod || info.state == .inBillingRetry {
                        Label("Payment issue — update your card", systemImage: "exclamationmark.triangle.fill")
                            .foregroundStyle(.red)
                    }
                }
            }

            // Actions
            Section {
                Button("Manage Subscription") {
                    Task { try? await Payo.showManageSubscriptions() }
                }
                Button("Restore Purchases") {
                    Task { try? await Payo.restorePurchases() }
                }
            }
        }
        .task {
            subInfo = await Payo.subscriptionInfo()
        }
    }
}

Button("Log Out") {
    Task {
        await Payo.reset()
        // Automatically re-initializes from Payo.plist
    }
}