import SwiftUI
#if canImport(UIKit)
import UIKit
#elseif canImport(AppKit)
import AppKit
#endif

struct CheckoutView: View {
    @Binding var appState: AppState

    @State var storeInfo: StoreInfoResult? = nil
    @State var errorMessage: String? = nil
    @State var deliveryType: CheckoutDeliveryType = .delivery
    @State var paymentMethod: CheckoutPaymentMethod = .pix
    @State var useInAppPayment = true
    @State var discountValue: Double = 0
    @State var baseDeliveryFee: Double? = nil
    @State var selectedCustomerAddress: CustomerAddress? = nil
    @State var addressValidationMessage: String? = nil
    @State var addressValidationBlocked = false
    @State var isValidatingAddress = false
    @State var showAddressNotServedAlert = false
    @State var isRestoringAddress = false
    @State var lastAcceptedAddressState: AddressState? = nil
    @State var isSubmittingOrder = false
    @State var pixPaymentContext: PixPaymentContext? = nil
    @State var cardPaymentContext: CardPaymentContext? = nil
    @State var orderTrackingContext: OrderTrackingContext? = nil
    @State var savedCards: [SavedCard] = []
    @State var showCardSelectionSheet = false

    var paymentConfig: StorePaymentMethodsInfo? { storeInfo?.paymentMethods }

    var availableDeliveryTypes: [CheckoutDeliveryType] {
        let deliveryEnabled = paymentConfig?.paymentOnDelivery ?? true
        let pickupEnabled = paymentConfig?.paymentOnPickup ?? true
        var values: [CheckoutDeliveryType] = []
        if deliveryEnabled { values.append(.delivery) }
        if pickupEnabled { values.append(.pickup) }
        return values.isEmpty ? [.delivery, .pickup] : values
    }

    var availableInAppPaymentMethods: [CheckoutPaymentMethod] {
        [.pix, .creditCard]
    }

    var availableStoreMachineMethods: [CheckoutPaymentMethod] {
        var methods: [CheckoutPaymentMethod] = []
        if paymentConfig?.acceptCash == true { methods.append(.money) }
        if paymentConfig?.hasAnyCreditCard == true { methods.append(.creditCard) }
        if paymentConfig?.hasAnyDebitCard == true { methods.append(.debitCard) }
        if paymentConfig?.hasAnyVoucher == true { methods.append(.voucher) }
        return methods
    }

    var isDeliveryMode: Bool {
        deliveryType == .delivery
    }

    private var deliveryToggle: Binding<Bool> {
        Binding(
            get: { isDeliveryMode },
            set: { isOn in
                let next: CheckoutDeliveryType = isOn ? .delivery : .pickup
                if availableDeliveryTypes.contains(next) {
                    deliveryType = next
                }
            }
        )
    }

    private var subtotalValue: Double {
        appState.cart.items.reduce(0) { $0 + (Double($1.quantity) * $1.unitPrice) }
    }

    private var deliveryFeeValue: Double {
        isDeliveryMode ? (baseDeliveryFee ?? 0) : 0
    }

    var totalValue: Double {
        max(0, subtotalValue + deliveryFeeValue - discountValue)
    }

    private var sectionTitleColor: Color {
        AppColors.textMuted
    }

    var canConfirmPayment: Bool {
        if isDeliveryMode {
            if addressValidationBlocked { return false }
            if baseDeliveryFee == nil { return false }
            if isValidatingAddress { return false }
        }
        if useInAppPayment == false && availableStoreMachineMethods.isEmpty { return false }
        return true
    }

    var body: some View {
        ScrollView(showsIndicators: false) {
            VStack(alignment: .leading, spacing: 18) {
                deliveryTypeSection
                addressSection
                orderSummarySection
                paymentSection

                if let errorMessage, errorMessage.isEmpty == false {
                    Text(errorMessage)
                        .font(.caption)
                        .foregroundStyle(Color.red)
                }

                if let addressValidationMessage, addressValidationMessage.isEmpty == false {
                    Text(addressValidationMessage)
                        .font(.caption)
                        .foregroundStyle(addressValidationBlocked ? Color.red : AppColors.primary)
                }
            }
            .padding(.horizontal, 20)
            .padding(.top, 16)
            .padding(.bottom, 10)
        }
        .background(AppColors.backgroundLight)
        .navigationTitle("Finalizar Pedido")
        .appInlineNavigationTitle()
        .appBottomSafeAreaInset {
            bottomBar
        }
        .task {
            await loadStoreInfoIfNeeded()
            await refreshSelectedCustomerAddress()
            normalizeSelectedOptions()
            await validateDeliveryAddressIfNeeded()
        }
        .onChange(of: checkoutAddressWatchKey) { _, _ in
            if isRestoringAddress { return }
            Task {
                await refreshSelectedCustomerAddress()
                await validateDeliveryAddressIfNeeded()
            }
        }
        .onChange(of: deliveryType) { _, _ in
            Task {
                await validateDeliveryAddressIfNeeded()
            }
        }
        .alert("Seu endereço não é atendido por esta loja.\nDeseja trocar mesmo assim?", isPresented: $showAddressNotServedAlert) {
            Button("Não", role: .cancel) {
                restoreLastAcceptedAddress()
            }
            Button("Sim", role: .destructive) {
                appState.cart.clear()
                addressValidationBlocked = false
                addressValidationMessage = nil
            }
        }
        .navigationDestination(item: $pixPaymentContext) { context in
            PaymentPixView(
                context: context,
                appState: $appState,
                onPaymentConfirmed: {
                    appState.cart.clear()
                    SessionStateStore.clearPendingCartOrder()
                }
            ) {
                appState.cart.clear()
                SessionStateStore.clearPendingCartOrder()
                orderTrackingContext = OrderTrackingContext(orderId: context.orderId, shortId: context.shortId)
            }
        }
        .navigationDestination(item: $cardPaymentContext) { context in
            PaymentCardView(
                context: context,
                appState: $appState,
                onOrderCreated: { orderId, shortId in
                    appState.cart.clear()
                    SessionStateStore.clearPendingCartOrder()
                    orderTrackingContext = OrderTrackingContext(orderId: orderId, shortId: shortId)
                }
            )
        }
        .sheet(isPresented: $showCardSelectionSheet) {
            let cardContext = CardPaymentContext.build(
                storeId: appState.cart.storeId ?? "",
                total: totalValue,
                deliveryType: deliveryType.rawValue,
                profile: appState.profile,
                address: selectedCustomerAddress,
                items: appState.cart.toOrderItemsPayload()
            )
            CardSelectionSheet(
                savedCards: savedCards,
                cardContext: cardContext,
                appState: $appState,
                onSavedCardConfirmed: { cardId in
                    showCardSelectionSheet = false
                    Task {
                        guard let storeId = appState.cart.storeId else { return }
                        await confirmOrderWithSavedCard(cardId: cardId, storeId: storeId)
                    }
                },
                onOrderCreated: { orderId, shortId in
                    showCardSelectionSheet = false
                    appState.cart.clear()
                    SessionStateStore.clearPendingCartOrder()
                    orderTrackingContext = OrderTrackingContext(orderId: orderId, shortId: shortId)
                }
            )
        }
        .task(id: paymentMethod) {
            if paymentMethod == .creditCard && useInAppPayment {
                await loadSavedCards()
            }
        }
        .navigationDestination(item: $orderTrackingContext) { context in
            OrderTrackingView(orderId: context.orderId, initialShortId: context.shortId)
        }
    }

    private var deliveryTypeSection: some View {
        VStack(alignment: .leading, spacing: 10) {
            Text("TIPO DE ENTREGA")
                .font(AppTypography.overline)
                .foregroundStyle(sectionTitleColor)

            HStack(spacing: 10) {
                VStack(alignment: .leading, spacing: 2) {
                    Text(isDeliveryMode ? "Entrega" : "Retirada")
                        .font(AppTypography.heading3)
                        .foregroundStyle(AppColors.textPrimary)
                }
                Spacer()
                Toggle("", isOn: deliveryToggle)
                    .labelsHidden()
                    .tint(AppColors.primary)
                    .disabled(availableDeliveryTypes.count <= 1)
            }
            .padding(14)
            .background(AppColors.surface)
            .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
        }
    }

    private var addressSection: some View {
        VStack(alignment: .leading, spacing: 10) {
            Text(addressSectionTitle)
                .font(AppTypography.overline)
                .foregroundStyle(sectionTitleColor)

            HStack(spacing: 12) {
                Circle()
                    .fill(AppColors.brandSoft)
                    .frame(width: 44, height: 44)
                    .overlay(
                        Image(systemName: "mappin.and.ellipse")
                            .foregroundStyle(AppColors.primary)
                    )

                VStack(alignment: .leading, spacing: 4) {
                    Text(isDeliveryMode ? "Casa" : (appState.cart.storeName ?? "Loja"))
                        .font(AppTypography.heading3)
                        .foregroundStyle(AppColors.textPrimary)
                    Text(isDeliveryMode ? customerAddressLabel : storeAddressLabel)
                        .font(AppTypography.body)
                        .foregroundStyle(AppColors.textMuted)
                }

                Spacer()

                if isDeliveryMode {
                    Button("Alterar") {
                        appState.activeModal = .addressPicker
                    }
                    .font(AppTypography.heading3)
                    .foregroundStyle(AppColors.primary)
                    .buttonStyle(.plain)
                }
            }
            .padding(14)
            .background(AppColors.surface)
            .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
        }
    }

    private var orderSummarySection: some View {
        VStack(alignment: .leading, spacing: 10) {
            Text("RESUMO DO PEDIDO")
                .font(AppTypography.overline)
                .foregroundStyle(sectionTitleColor)

            VStack(alignment: .leading, spacing: 12) {
                ForEach(appState.cart.items) { item in
                    HStack(alignment: .center, spacing: 10) {
                        Text("\(item.quantity)x")
                            .font(AppTypography.heading3)
                            .foregroundStyle(AppColors.textMuted)
                            .padding(.horizontal, 10)
                            .padding(.vertical, 6)
                            .background(AppColors.backgroundLight)
                            .clipShape(RoundedRectangle(cornerRadius: 8, style: .continuous))

                        VStack(alignment: .leading, spacing: 2) {
                            Text(item.name)
                                .font(AppTypography.heading3)
                                .foregroundStyle(AppColors.textPrimary)
                            if let details = item.details, details.isEmpty == false {
                                Text(details)
                                    .font(.caption)
                                    .foregroundStyle(AppColors.textMuted)
                                    .lineLimit(1)
                            }
                        }
                        Spacer()
                        Text(formatCurrency(Double(item.quantity) * item.unitPrice))
                            .font(AppTypography.heading3)
                            .foregroundStyle(AppColors.textPrimary)
                    }
                }

                Divider()
                    .padding(.vertical, 4)

                summaryRow("Subtotal", formatCurrency(subtotalValue))
                summaryRow("Taxa de entrega", deliveryFeeLabel)
                summaryRow("Desconto", "-\(formatCurrency(discountValue))", valueColor: Color.green)
            }
            .padding(14)
            .background(AppColors.surface)
            .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
        }
    }

    private var paymentSection: some View {
        VStack(alignment: .leading, spacing: 10) {
            Text("MÉTODO DE PAGAMENTO")
                .font(AppTypography.overline)
                .foregroundStyle(sectionTitleColor)

            VStack(alignment: .leading, spacing: 0) {
                // Toggle row
                HStack(spacing: 12) {
                    VStack(alignment: .leading, spacing: 2) {
                        Text(useInAppPayment ? "Pagar Pelo App" : "Pagar Na Maquininha")
                            .font(AppTypography.heading3)
                            .foregroundStyle(AppColors.textPrimary)
                        Text(useInAppPayment ? "Mais rápido e seguro" : "Na entrega/retirada com a loja")
                            .font(.caption)
                            .foregroundStyle(AppColors.textMuted)
                    }
                    Spacer()
                    Toggle("", isOn: Binding(
                        get: { useInAppPayment },
                        set: { newValue in
                            withAnimation(.easeInOut(duration: 0.2)) {
                                useInAppPayment = newValue
                                if newValue {
                                    if availableInAppPaymentMethods.contains(paymentMethod) == false {
                                        paymentMethod = .pix
                                    }
                                } else {
                                    guard availableStoreMachineMethods.isEmpty == false else {
                                        useInAppPayment = true
                                        return
                                    }
                                    if availableStoreMachineMethods.contains(paymentMethod) == false,
                                       let first = availableStoreMachineMethods.first {
                                        paymentMethod = first
                                    }
                                }
                            }
                        }
                    ))
                    .labelsHidden()
                    .tint(AppColors.primary)
                }
                .padding(14)

                Divider()
                    .padding(.horizontal, 14)

                // Methods list
                if useInAppPayment {
                    ForEach(availableInAppPaymentMethods, id: \.rawValue) { method in
                        paymentRow(method, isInAppGroup: true)
                        if method != availableInAppPaymentMethods.last {
                            Divider().padding(.horizontal, 14)
                        }
                    }
                } else {
                    if availableStoreMachineMethods.isEmpty {
                        Text("Loja não informou métodos presenciais.")
                            .font(AppTypography.body)
                            .foregroundStyle(AppColors.textMuted)
                            .padding(14)
                    } else {
                        ForEach(availableStoreMachineMethods, id: \.rawValue) { method in
                            paymentRow(method, isInAppGroup: false)
                            if method != availableStoreMachineMethods.last {
                                Divider().padding(.horizontal, 14)
                            }
                        }
                    }
                }
            }
            .background(AppColors.surface)
            .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
        }
    }

    private func paymentRow(_ method: CheckoutPaymentMethod, isInAppGroup: Bool) -> some View {
        let subtitle = paymentSubtitle(for: method, isInAppGroup: isInAppGroup)
        return Button {
            paymentMethod = method
        } label: {
            HStack(spacing: 12) {
                RoundedRectangle(cornerRadius: 10, style: .continuous)
                    .fill(AppColors.backgroundLight)
                    .frame(width: 54, height: 54)
                    .overlay(
                        Image(systemName: method.iconName)
                            .font(.system(size: 20, weight: .semibold))
                            .foregroundStyle(method == .pix ? Color.green : AppColors.textPrimary)
                    )

                VStack(alignment: .leading, spacing: 3) {
                    Text(method.label)
                        .font(AppTypography.heading3)
                        .foregroundStyle(AppColors.textPrimary)
                    if let subtitle {
                        Text(subtitle)
                            .font(.caption)
                            .foregroundStyle(AppColors.textMuted)
                    }
                }
                Spacer()

                Circle()
                    .stroke(paymentMethod == method ? AppColors.tertiary : AppColors.textMuted.opacity(0.45), lineWidth: 2)
                    .frame(width: 24, height: 24)
                    .background(
                        Circle()
                            .fill(paymentMethod == method ? AppColors.tertiary : Color.clear)
                    )
            }
            .padding(14)
        }
        .buttonStyle(.plain)
    }

    private func paymentSubtitle(for method: CheckoutPaymentMethod, isInAppGroup: Bool) -> String? {
        if isInAppGroup == false {
            if method == .pix {
                return "Pagamento presencial (QR da loja)"
            }
            return nil
        }
        return method.subtitle
    }


    private var bottomBar: some View {
        VStack(spacing: 12) {
            HStack {
                Text("Total a pagar")
                    .font(AppTypography.heading3)
                    .foregroundStyle(AppColors.textMuted)
                Spacer()
                Text(formatCurrency(totalValue))
                    .font(AppTypography.heading1)
                    .foregroundStyle(AppColors.textPrimary)
            }

            Button {
                Task { await handleConfirmPaymentTap() }
            } label: {
                HStack(spacing: 10) {
                    Text("Confirmar e Pagar")
                        .font(AppTypography.heading2)
                    Image(systemName: "checkmark")
                        .font(.system(size: 18, weight: .bold))
                }
                .foregroundStyle(AppColors.textInverse)
                .frame(maxWidth: .infinity, minHeight: 54)
                .background(AppColors.primary)
                .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
            }
            .buttonStyle(.plain)
            .disabled(canConfirmPayment == false || isValidatingAddress || isSubmittingOrder)
            .opacity((canConfirmPayment && isValidatingAddress == false && isSubmittingOrder == false) ? 1 : 0.65)
        }
        .padding(.horizontal, 20)
        .padding(.top, 10)
        .padding(.bottom, UIDevice.bottomNotch + 40)
        .background(AppColors.surface.opacity(0.98))
    }

    private func summaryRow(_ title: String, _ value: String, valueColor: Color? = nil) -> some View {
        HStack {
            Text(title)
                .font(AppTypography.body)
                .foregroundStyle(AppColors.textMuted)
            Spacer()
            Text(value)
                .font(AppTypography.heading3)
                .foregroundStyle(valueColor ?? AppColors.textMuted)
        }
    }

    private var customerAddressLabel: String {
        if let address = selectedCustomerAddress {
            let street = (address.address ?? "").trimmingCharacters(in: .whitespacesAndNewlines)
            let number = (address.number ?? "").trimmingCharacters(in: .whitespacesAndNewlines)
            let neighborhood = (address.neighborhood ?? "").trimmingCharacters(in: .whitespacesAndNewlines)
            let city = (address.city ?? "").trimmingCharacters(in: .whitespacesAndNewlines)
            let state = (address.state ?? "").trimmingCharacters(in: .whitespacesAndNewlines)
            let firstLine = [street, number].filter { $0.isEmpty == false }.joined(separator: ", ")
            let secondLine = [neighborhood, city, state].filter { $0.isEmpty == false }.joined(separator: " - ")
            let joined = [firstLine, secondLine].filter { $0.isEmpty == false }.joined(separator: "\n")
            if joined.isEmpty == false { return joined }
        }

        let value = appState.address.display.trimmingCharacters(in: .whitespacesAndNewlines)
        return value.isEmpty ? "Defina seu endereço" : value
    }

    private var addressSectionTitle: String {
        if isDeliveryMode {
            return "ENDEREÇO DE ENTREGA"
        }
        let storeName = (appState.cart.storeName ?? "LOJA")
            .trimmingCharacters(in: .whitespacesAndNewlines)
            .uppercased()
        return "ENDEREÇO DE \(storeName)"
    }

    private var storeAddressLabel: String {
        guard let address = storeInfo?.address else { return "Endereço da loja indisponível" }
        let street = (address.street ?? "").trimmingCharacters(in: .whitespacesAndNewlines)
        let number = (address.number ?? "").trimmingCharacters(in: .whitespacesAndNewlines)
        let neighborhood = (address.neighborhood ?? "").trimmingCharacters(in: .whitespacesAndNewlines)
        let city = (address.city ?? "").trimmingCharacters(in: .whitespacesAndNewlines)
        let state = (address.state ?? "").trimmingCharacters(in: .whitespacesAndNewlines)
        let firstLine = [street, number].filter { $0.isEmpty == false }.joined(separator: ", ")
        let secondLine = [neighborhood, city, state].filter { $0.isEmpty == false }.joined(separator: " - ")
        let joined = [firstLine, secondLine].filter { $0.isEmpty == false }.joined(separator: "\n")
        return joined.isEmpty ? "Endereço da loja indisponível" : joined
    }

    private var deliveryFeeLabel: String {
        if isDeliveryMode == false {
            return formatCurrency(0)
        }
        if let baseDeliveryFee {
            return formatCurrency(baseDeliveryFee)
        }
        return "Calculando..."
    }

}

struct PixPaymentContext: Identifiable, Hashable {
    let id: String
    let orderId: String
    let shortId: String?
    let storeId: String
    let copyPaste: String
    let qrCodeImageBase64: String?
    let expirationDate: String?
    // Para troca de pagamento
    let total: Double
    let profileName: String
    let profileEmail: String
    let profilePhone: String
    let addressZip: String?
    let addressNumber: String?
    let deliveryType: String
    let itemsJSON: String
}

struct OrderTrackingContext: Identifiable, Hashable {
    var id: String { orderId }
    let orderId: String
    let shortId: String?
}

struct CardPaymentContext: Identifiable, Hashable {
    let id: String
    let storeId: String
    let total: Double
    let deliveryType: String
    let profileName: String
    let profileEmail: String
    let profilePhone: String
    let addressStreet: String?
    let addressNumber: String?
    let addressNeighborhood: String?
    let addressCity: String?
    let addressState: String?
    let addressZip: String?
    let addressComplement: String?
    let itemsJSON: String

    static func build(storeId: String, total: Double, deliveryType: String, profile: ProfileState, address: CustomerAddress?, items: [CreateOrderItemPayload]) -> CardPaymentContext {
        let itemsData = (try? JSONEncoder().encode(items)).flatMap { String(data: $0, encoding: .utf8) } ?? "[]"
        return CardPaymentContext(
            id: UUID().uuidString,
            storeId: storeId,
            total: total,
            deliveryType: deliveryType,
            profileName: profile.name,
            profileEmail: profile.email,
            profilePhone: profile.phone,
            addressStreet: address?.address,
            addressNumber: address?.number,
            addressNeighborhood: address?.neighborhood,
            addressCity: address?.city,
            addressState: address?.state,
            addressZip: address?.zipCode,
            addressComplement: address?.complement,
            itemsJSON: itemsData
        )
    }

    var addressPayload: CreateOrderAddressPayload? {
        guard let street = addressStreet, street.isEmpty == false,
              let number = addressNumber, number.isEmpty == false,
              let neighborhood = addressNeighborhood, neighborhood.isEmpty == false else { return nil }
        return CreateOrderAddressPayload(street: street, number: number, neighborhood: neighborhood, city: addressCity, state: addressState, zip: addressZip, complement: addressComplement)
    }

    var orderItems: [CreateOrderItemPayload] {
        guard let data = itemsJSON.data(using: .utf8),
              let decoded = try? JSONDecoder().decode([CreateOrderItemPayload].self, from: data) else { return [] }
        return decoded
    }
}

struct PaymentPixView: View {
    let context: PixPaymentContext
    @Binding var appState: AppState
    var onPaymentConfirmed: (() -> Void)? = nil
    var onOpenTracking: (() -> Void)? = nil
    @Environment(\.dismiss) var dismiss
    @State var tracker = OrderRealtimeTracker()
    @State var latestOrder: PublicOrderResult? = nil
    @State var hasOpenedTracking = false
    @State var hasShownPixExpiredSnackbar = false
    @State var currentTime = Date()
    @State var showChangePaymentSheet = false
    @State var savedCards: [SavedCard] = []
    @State var currentContext: PixPaymentContext

    init(context: PixPaymentContext, appState: Binding<AppState>, onPaymentConfirmed: (() -> Void)? = nil, onOpenTracking: (() -> Void)? = nil) {
        self.context = context
        self._appState = appState
        self.onPaymentConfirmed = onPaymentConfirmed
        self.onOpenTracking = onOpenTracking
        _currentContext = State(initialValue: context)
    }

    private var qrImageSource: String? {
        guard let raw = currentContext.qrCodeImageBase64?.trimmingCharacters(in: .whitespacesAndNewlines),
              raw.isEmpty == false else { return nil }
        if raw.lowercased().hasPrefix("data:image") { return raw }
        return "data:image/png;base64,\(raw)"
    }

    var body: some View {
        ScrollView(showsIndicators: false) {
            VStack(spacing: 14) {
                RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous)
                    .fill(AppColors.surface)
                    .overlay(
                        VStack(spacing: 10) {
                            Text("Escaneie o QR Code abaixo ou copie o código para pagar no seu aplicativo do banco.")
                                .font(AppTypography.body)
                                .foregroundStyle(AppColors.textMuted)
                                .multilineTextAlignment(.center)
                                .padding(.horizontal, 12)
                                .padding(.top, 14)

                            AsyncStoreImage(imageURL: qrImageSource)
                                .frame(width: 220, height: 220)
                                .clipShape(RoundedRectangle(cornerRadius: 16, style: .continuous))
                                .overlay(
                                    RoundedRectangle(cornerRadius: 16, style: .continuous)
                                        .stroke(AppColors.tertiary.opacity(0.35), lineWidth: 2)
                                )

                            Text("AGUARDANDO PAGAMENTO")
                                .font(AppTypography.heading3)
                                .foregroundStyle(AppColors.textPrimary)
                                .padding(.horizontal, 20)
                                .padding(.vertical, 8)
                                .background(AppColors.brandSoft)
                                .clipShape(Capsule())
                        }
                    )
                    .frame(maxWidth: .infinity, minHeight: 380)

                Text("Código PIX")
                    .font(AppTypography.heading3)
                    .foregroundStyle(AppColors.textPrimary)
                
                RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous)
                    .fill(AppColors.surface)
                    .frame(height: 20)
                    .overlay(
                        VStack(spacing: 8) {
                            Text(currentContext.copyPaste)
                                .font(.system(size: 12, weight: .medium, design: .monospaced))
                                .foregroundStyle(AppColors.textMuted)
                                .lineLimit(0)
                                .multilineTextAlignment(.center)
                                .padding(.horizontal, 10)

                        }
                        .padding(.vertical, 14)
                    )

                if let expirationDate = currentContext.expirationDate, expirationDate.isEmpty == false {
                    Text(expirationLabel)
                        .font(.caption)
                        .foregroundStyle(isPixExpired ? Color.red : AppColors.textMuted)
                }

                HStack(spacing: 10) {
                    PrimaryButton(title: "Copiar Código PIX") {
                        if isPixExpired {
                            showPixExpiredSnackbar()
                            return
                        }
                        copyToClipboard(currentContext.copyPaste)
                        SnackbarCenter.shared.show(title: "Código PIX copiado.", style: .success, icon: "doc.on.doc.fill", duration: 2.0)
                    }
                    .disabled(isPixExpired)
                    .opacity(isPixExpired ? 0.5 : 1.0)

                    Button {
                        Task { await loadSavedCards() }
                        showChangePaymentSheet = true
                    } label: {
                        HStack(spacing: 6) {
                            Text("Trocar")
                                .font(AppTypography.heading3)
                            Image(systemName: "chevron.down")
                                .font(.system(size: 12, weight: .semibold))
                        }
                        .foregroundStyle(AppColors.textPrimary)
                        .frame(height: 54)
                        .padding(.horizontal, 16)
                        .background(AppColors.surface)
                        .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
                    }
                    .buttonStyle(.plain)
                }
                .padding(.top, 10)
            }
            .padding(20)
        }
        .background(AppColors.backgroundLight)
        .navigationTitle("Pagamento via PIX")
        .appInlineNavigationTitle()
        .sheet(isPresented: $showChangePaymentSheet) {
            ChangePaymentSheet(
                pixContext: currentContext,
                savedCards: savedCards,
                appState: $appState,
                onChanged: { newContext in
                    showChangePaymentSheet = false
                    if let newContext {
                        currentContext = newContext
                        tracker.stop()
                        tracker.start(orderId: newContext.orderId, jwt: DefaultTokenStore().jwt)
                    }
                },
                onConfirmed: {
                    showChangePaymentSheet = false
                    onPaymentConfirmed?()
                    openTrackingOnce()
                }
            )
        }
        .task {
            tracker.onOrderUpdated = { updated in
                latestOrder = updated
                if updated.isPaymentConfirmed {
                    onPaymentConfirmed?()
                    openTrackingOnce()
                }
            }
            tracker.start(orderId: currentContext.orderId, jwt: DefaultTokenStore().jwt)
        }
        .task {
            while Task.isCancelled == false {
                currentTime = Date()
                if isPixExpired {
                    showPixExpiredSnackbar()
                    return
                }
                try? await Task.sleep(nanoseconds: 1_000_000_000)
            }
        }
        .onDisappear {
            tracker.stop()
        }
    }

    private func openTrackingOnce() {
        guard hasOpenedTracking == false else { return }
        hasOpenedTracking = true
        onOpenTracking?()
    }

    private func copyToClipboard(_ value: String) {
        appWriteClipboardText(value)
    }

    @MainActor
    private func loadSavedCards() async {
        guard savedCards.isEmpty else { return }
        if let cards = try? await ApiService().listCards().result {
            savedCards = cards
        }
    }

    private var parsedExpirationDate: Date? {
        let raw = (currentContext.expirationDate ?? "").trimmingCharacters(in: .whitespacesAndNewlines)
        guard raw.isEmpty == false else { return nil }

        let iso = ISO8601DateFormatter()
        iso.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
        if let date = iso.date(from: raw) { return date }
        iso.formatOptions = [.withInternetDateTime]
        if let date = iso.date(from: raw) { return date }

        let formatter = DateFormatter()
        formatter.locale = Locale(identifier: "pt_BR")
        let formats = [
            "yyyy-MM-dd HH:mm:ss",
            "yyyy-MM-dd'T'HH:mm:ss",
            "yyyy-MM-dd'T'HH:mm:ss.SSSZ",
            "dd/MM/yyyy HH:mm:ss",
            "dd/MM/yyyy HH:mm"
        ]
        for format in formats {
            formatter.dateFormat = format
            if let date = formatter.date(from: raw) {
                return date
            }
        }

        return nil
    }

    private var isPixExpired: Bool {
        guard let parsedExpirationDate else { return false }
        return currentTime >= parsedExpirationDate
    }

    private var expirationLabel: String {
        guard let parsedExpirationDate else {
            return "Expira em: --"
        }
        if isPixExpired {
            return "Expirado"
        }

        let remaining = max(0, Int(parsedExpirationDate.timeIntervalSince(currentTime)))
        let day = 24 * 60 * 60
        let hour = 60 * 60

        if remaining >= day {
            let days = remaining / day
            return "Expira em: \(days) dia(s)"
        }
        if remaining >= hour {
            let hours = remaining / hour
            return "Expira em: \(hours) hora(s)"
        }
        if remaining >= 60 {
            let minutes = remaining / 60
            return "Expira em: \(minutes) min"
        }
        return "Vai expirar em \(remaining) segundos"
    }

    private func showPixExpiredSnackbar() {
        guard hasShownPixExpiredSnackbar == false else { return }
        hasShownPixExpiredSnackbar = true
        SnackbarCenter.shared.show(
            title: "PIX expirou. Gere um novo pedido para continuar.",
            style: .warning,
            icon: "clock.badge.xmark.fill",
            duration: 4.0
        )
    }
}

// MARK: - CardSelectionSheet

struct CardSelectionSheet: View {
    let savedCards: [SavedCard]
    let cardContext: CardPaymentContext
    @Binding var appState: AppState
    let onSavedCardConfirmed: (String) -> Void
    let onOrderCreated: (String, String?) -> Void

    @Environment(\.dismiss) var dismiss
    @State var selectedCardId: String?
    @State var isSubmitting = false
    @State var showNewCardSheet = false

    init(savedCards: [SavedCard], cardContext: CardPaymentContext, appState: Binding<AppState>, onSavedCardConfirmed: @escaping (String) -> Void, onOrderCreated: @escaping (String, String?) -> Void) {
        self.savedCards = savedCards
        self.cardContext = cardContext
        self._appState = appState
        self.onSavedCardConfirmed = onSavedCardConfirmed
        self.onOrderCreated = onOrderCreated
        _selectedCardId = State(initialValue: savedCards.first(where: { $0.isDefault })?.id ?? savedCards.first?.id)
    }

    var body: some View {
        VStack(spacing: 0) {
            // Header
            HStack {
                Text("Selecionar Cartão")
                    .font(AppTypography.heading2)
                    .foregroundStyle(AppColors.textPrimary)
                Spacer()
                Button {
                    dismiss()
                } label: {
                    Image(systemName: "xmark")
                        .font(.system(size: 12, weight: .bold))
                        .foregroundStyle(AppColors.textMuted)
                        .frame(width: 30, height: 30)
                        .background(AppColors.surface)
                        .clipShape(Circle())
                }
                .buttonStyle(.plain)
            }
            .padding(.horizontal, 20)
            .padding(.top, 20)
            .padding(.bottom, 16)

            ScrollView(showsIndicators: false) {
                VStack(alignment: .leading, spacing: 16) {
                    if savedCards.isEmpty == false {
                        VStack(alignment: .leading, spacing: 0) {
                            ForEach(savedCards) { card in
                                savedCardRow(card)
                                if card.id != savedCards.last?.id {
                                    Divider().padding(.horizontal, 14)
                                }
                            }
                        }
                        .background(AppColors.surface)
                        .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))

                        if let selectedCardId {
                            PrimaryButton(title: isSubmitting ? "Processando..." : "Pagar \(formatCurrency(cardContext.total))") {
                                guard isSubmitting == false else { return }
                                onSavedCardConfirmed(selectedCardId)
                            }
                            .disabled(isSubmitting)
                        }

                        Text("ou")
                            .font(AppTypography.caption)
                            .foregroundStyle(AppColors.textMuted)
                            .frame(maxWidth: .infinity, alignment: .center)
                    }

                    Button {
                        showNewCardSheet = true
                    } label: {
                        HStack(spacing: 10) {
                            Image(systemName: "plus.circle.fill")
                                .font(.system(size: 18))
                                .foregroundStyle(AppColors.primary)
                            Text("Adicionar novo cartão")
                                .font(AppTypography.heading3)
                                .foregroundStyle(AppColors.primary)
                            Spacer()
                        }
                        .padding(14)
                        .background(AppColors.surface)
                        .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
                    }
                    .buttonStyle(.plain)
                }
                .padding(.horizontal, 20)
                .padding(.bottom, 32)
            }
        }
        .background(AppColors.backgroundLight)
        .sheet(isPresented: $showNewCardSheet) {
            PaymentCardView(
                context: cardContext,
                appState: $appState,
                onOrderCreated: { orderId, shortId in
                    showNewCardSheet = false
                    onOrderCreated(orderId, shortId)
                }
            )
        }
    }

    private func savedCardRow(_ card: SavedCard) -> some View {
        Button {
            selectedCardId = card.id
        } label: {
            HStack(spacing: 12) {
                Image(systemName: "creditcard.fill")
                    .font(.system(size: 20))
                    .foregroundStyle(AppColors.textPrimary)
                    .frame(width: 44, height: 44)
                    .background(AppColors.backgroundLight)
                    .clipShape(RoundedRectangle(cornerRadius: 10, style: .continuous))

                VStack(alignment: .leading, spacing: 3) {
                    Text(card.displayLabel)
                        .font(AppTypography.heading3)
                        .foregroundStyle(AppColors.textPrimary)
                    Text("Vence \(card.expiryLabel)")
                        .font(.caption)
                        .foregroundStyle(AppColors.textMuted)
                }
                Spacer()
                Circle()
                    .stroke(selectedCardId == card.id ? AppColors.tertiary : AppColors.textMuted.opacity(0.45), lineWidth: 2)
                    .frame(width: 22, height: 22)
                    .background(Circle().fill(selectedCardId == card.id ? AppColors.tertiary : Color.clear))
            }
            .padding(14)
        }
        .buttonStyle(.plain)
    }

    private func formatCurrency(_ value: Double) -> String {
        String(format: "R$ %.2f", value).replacingOccurrences(of: ".", with: ",")
    }
}

// MARK: - PaymentCardView

struct PaymentCardView: View {
    let context: CardPaymentContext
    @Binding var appState: AppState
    let onOrderCreated: (String, String?) -> Void

    @Environment(\.dismiss) var dismiss
    @State var holderName: String
    @State var cardNumber = ""
    @State var expiry = ""
    @State var cvv = ""
    @State var cpf: String
    @State var saveCard = false
    @State var nickname = ""
    @State var isSubmitting = false

    init(context: CardPaymentContext, appState: Binding<AppState>, onOrderCreated: @escaping (String, String?) -> Void) {
        self.context = context
        self._appState = appState
        self.onOrderCreated = onOrderCreated
        _holderName = State(initialValue: context.profileName)
        _cpf = State(initialValue: appState.wrappedValue.profile.cpf)
    }

    var canSubmit: Bool {
        holderName.trimmingCharacters(in: .whitespaces).isEmpty == false &&
        cardNumber.filter(\.isNumber).count >= 13 &&
        expiry.filter(\.isNumber).count == 6 &&
        cvv.filter(\.isNumber).count >= 3 &&
        cpf.filter(\.isNumber).count == 11
    }

    var body: some View {
        VStack(spacing: 0) {
            HStack {
                Text("Novo Cartão")
                    .font(AppTypography.heading2)
                    .foregroundStyle(AppColors.textPrimary)
                Spacer()
                Button {
                    dismiss()
                } label: {
                    Image(systemName: "xmark")
                        .font(.system(size: 12, weight: .bold))
                        .foregroundStyle(AppColors.textMuted)
                        .frame(width: 30, height: 30)
                        .background(AppColors.surface)
                        .clipShape(Circle())
                }
                .buttonStyle(.plain)
            }
            .padding(.horizontal, 20)
            .padding(.top, 20)
            .padding(.bottom, 16)

        ScrollView(showsIndicators: false) {
            VStack(alignment: .leading, spacing: 16) {
                // Total
                HStack {
                    VStack(alignment: .leading, spacing: 2) {
                        Text("Total do Pedido")
                            .font(AppTypography.caption)
                            .foregroundStyle(AppColors.textMuted)
                        Text(formatCurrency(context.total))
                            .font(AppTypography.heading2)
                            .foregroundStyle(AppColors.textPrimary)
                    }
                    Spacer()
                }
                .padding(14)
                .background(AppColors.surface)
                .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))

                // Dados do cartão
                VStack(alignment: .leading, spacing: 0) {
                    sectionHeader("DADOS DO CARTÃO")
                    VStack(spacing: 10) {
                        labeledField("Número do Cartão", placeholder: "0000 0000 0000 0000", text: $cardNumber)
                            .keyboardType(.numberPad)
                            .onChange(of: cardNumber) { _, v in
                                let d = String(v.filter(\.isNumber).prefix(16))
                                let masked = stride(from: 0, to: d.count, by: 4)
                                    .map { i -> String in
                                        let start = d.index(d.startIndex, offsetBy: i)
                                        let end = d.index(start, offsetBy: min(4, d.count - i))
                                        return String(d[start..<end])
                                    }.joined(separator: " ")
                                if masked != v { cardNumber = masked }
                            }

                        labeledField("Nome no Cartão", placeholder: "Como impresso no cartão", text: $holderName)

                        HStack(spacing: 10) {
                            labeledField("Validade", placeholder: "MM/AAAA", text: $expiry)
                                .keyboardType(.numberPad)
                                .onChange(of: expiry) { _, v in
                                    let d = String(v.filter(\.isNumber).prefix(6))
                                    let masked: String
                                    if d.count <= 2 { masked = d }
                                    else { masked = "\(d.prefix(2))/\(d.dropFirst(2))" }
                                    if masked != v { expiry = masked }
                                }

                            labeledField("CVV", placeholder: "•••", text: $cvv)
                                .keyboardType(.numberPad)
                                .onChange(of: cvv) { _, v in
                                    let d = String(v.filter(\.isNumber).prefix(4))
                                    if d != v { cvv = d }
                                }
                        }

                        labeledField("CPF do Titular", placeholder: "000.000.000-00", text: $cpf)
                            .keyboardType(.numberPad)
                            .onChange(of: cpf) { _, v in
                                let d = String(v.filter(\.isNumber).prefix(11))
                                let masked: String
                                if d.count <= 3 { masked = d }
                                else if d.count <= 6 { masked = "\(d.prefix(3)).\(d.dropFirst(3))" }
                                else if d.count <= 9 { masked = "\(d.prefix(3)).\(d.dropFirst(3).prefix(3)).\(d.dropFirst(6))" }
                                else { masked = "\(d.prefix(3)).\(d.dropFirst(3).prefix(3)).\(d.dropFirst(6).prefix(3))-\(d.dropFirst(9))" }
                                if masked != v { cpf = masked }
                            }
                    }
                    .padding(14)
                }
                .background(AppColors.surface)
                .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))

                // Salvar cartão
                VStack(spacing: 0) {
                    HStack {
                        VStack(alignment: .leading, spacing: 2) {
                            Text("Salvar cartão")
                                .font(AppTypography.heading3)
                                .foregroundStyle(AppColors.textPrimary)
                            Text("Pague mais rápido nas próximas compras")
                                .font(.caption)
                                .foregroundStyle(AppColors.textMuted)
                        }
                        Spacer()
                        Toggle("", isOn: $saveCard)
                            .labelsHidden()
                            .tint(AppColors.primary)
                    }
                    .padding(14)

                    if saveCard {
                        Divider().padding(.horizontal, 14)
                        labeledField("Apelido do cartão (opcional)", placeholder: "Ex: Meu Visa", text: $nickname)
                            .padding(14)
                    }
                }
                .background(AppColors.surface)
                .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
                .animation(.easeInOut(duration: 0.2), value: saveCard)

                PrimaryButton(title: isSubmitting ? "Processando..." : "Confirmar e Pagar") {
                    guard canSubmit, isSubmitting == false else { return }
                    Task { await submitOrder() }
                }
                .disabled(canSubmit == false || isSubmitting)
            }
            .padding(20)
        }
        .background(AppColors.backgroundLight)
        } // VStack
        .background(AppColors.backgroundLight)
    }

    @MainActor
    private func submitOrder() async {
        isSubmitting = true
        defer { isSubmitting = false }

        let cleanCpf = cpf.filter(\.isNumber)
        let cleanCardNumber = cardNumber.filter(\.isNumber)
        let expiryParts = expiry.filter(\.isNumber)
        let expiryMonth = String(expiryParts.prefix(2))
        let expiryYear: String
        let yearPart = String(expiryParts.dropFirst(2))
        expiryYear = yearPart.count == 2 ? "20\(yearPart)" : yearPart

        let rawPhone = context.profilePhone.filter(\.isNumber)
        let phoneWithDdi = rawPhone.hasPrefix("55") ? rawPhone : "55\(rawPhone)"

        let holderInfo = SaveCardHolderInfoPayload(
            name: context.profileName,
            email: context.profileEmail,
            cpfCnpj: cleanCpf,
            postalCode: (context.addressZip ?? "").filter(\.isNumber),
            addressNumber: context.addressNumber ?? "",
            phone: phoneWithDdi
        )

        let creditCardPayload = CreditCardOrderPayload(
            holderName: holderName,
            number: cleanCardNumber,
            expiryMonth: expiryMonth,
            expiryYear: expiryYear,
            ccv: cvv
        )

        let payload = CreateOrderPayload(
            customer: CreateOrderCustomerPayload(name: context.profileName, phone: context.profilePhone, email: context.profileEmail, asaasId: nil),
            items: context.orderItems,
            total: context.total,
            paymentMethod: CheckoutPaymentMethod.creditCard.rawValue,
            deliveryType: context.deliveryType,
            address: context.addressPayload,
            savedCardId: nil,
            clientCpfCnpj: cleanCpf,
            creditCard: creditCardPayload,
            creditCardHolderInfo: holderInfo
        )

        do {
            // Save CPF locally for future use
            if cleanCpf.count == 11 {
                appState.profile.cpf = cleanCpf
                Task<Void, Never> {
                    do { _ = try await ApiService().updateProfileCpf(cpf: cleanCpf) } catch {}
                }
            }

            // Optionally save card
            if saveCard {
                let savePayload = SaveCardPayload(
                    creditCard: SaveCardCreditCardPayload(holderName: holderName, number: cleanCardNumber, expiryMonth: expiryMonth, expiryYear: expiryYear, ccv: cvv),
                    creditCardHolderInfo: holderInfo,
                    nickname: nickname.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty ? nil : nickname,
                    isDefault: false
                )
                Task<Void, Never> {
                    do { _ = try await ApiService().saveCard(payload: savePayload) } catch {}
                }
            }

            let response = try await ApiService().createOrder(storeId: context.storeId, payload: payload)
            if response.error {
                SnackbarCenter.shared.show(title: response.message ?? "Pagamento recusado.", style: .error, icon: "xmark.octagon.fill", duration: 3.5)
                return
            }
            guard let result = response.result else { return }
            let orderId = result.id ?? UUID().uuidString
            onOrderCreated(orderId, result.shortId)
        } catch let error as NetworkError {
            let message: String
            if case .httpError(_, let serverMessage) = error, let serverMessage, serverMessage.isEmpty == false {
                message = serverMessage
            } else {
                message = error.errorDescription ?? "Não foi possível processar o pagamento."
            }
            SnackbarCenter.shared.show(title: message, style: .error, icon: "xmark.octagon.fill", duration: 5.0)
        } catch {
            SnackbarCenter.shared.show(title: "Não foi possível processar o pagamento.", style: .error, icon: "xmark.octagon.fill", duration: 3.0)
        }
    }

    private func sectionHeader(_ text: String) -> some View {
        Text(text)
            .font(AppTypography.overline)
            .foregroundStyle(AppColors.textMuted)
            .padding(.horizontal, 14)
            .padding(.top, 12)
            .padding(.bottom, 4)
    }

    private func labeledField(_ label: String, placeholder: String, text: Binding<String>) -> some View {
        VStack(alignment: .leading, spacing: 6) {
            Text(label)
                .font(AppTypography.caption)
                .foregroundStyle(AppColors.textMuted)
            TextField(placeholder, text: text)
                .appNoAutoCap()
                .padding(.horizontal, 12)
                .frame(height: 46)
                .background(AppColors.backgroundLight)
                .clipShape(RoundedRectangle(cornerRadius: 10, style: .continuous))
        }
    }

    private func formatCurrency(_ value: Double) -> String {
        String(format: "R$ %.2f", value).replacingOccurrences(of: ".", with: ",")
    }
}

// MARK: - ChangePaymentSheet

struct ChangePaymentSheet: View {
    let pixContext: PixPaymentContext
    let savedCards: [SavedCard]
    @Binding var appState: AppState
    let onChanged: (PixPaymentContext?) -> Void
    let onConfirmed: () -> Void

    @Environment(\.dismiss) var dismiss
    @State var isSubmitting = false
    @State var showCardSheet = false

    var body: some View {
        VStack(spacing: 0) {
            HStack {
                Text("Trocar Pagamento")
                    .font(AppTypography.heading2)
                    .foregroundStyle(AppColors.textPrimary)
                Spacer()
                Button { dismiss() } label: {
                    Image(systemName: "xmark")
                        .font(.system(size: 12, weight: .bold))
                        .foregroundStyle(AppColors.textMuted)
                        .frame(width: 30, height: 30)
                        .background(AppColors.surface)
                        .clipShape(Circle())
                }
                .buttonStyle(.plain)
            }
            .padding(.horizontal, 20)
            .padding(.top, 20)
            .padding(.bottom, 16)

            ScrollView(showsIndicators: false) {
                VStack(spacing: 12) {
                    optionRow(icon: "qrcode", title: "Novo QR Code PIX", subtitle: "Gera um novo código PIX") {
                        Task { await changeToMethod("PIX") }
                    }
                    optionRow(icon: "creditcard.fill", title: "Cartão de Crédito", subtitle: "Débito imediato no cartão") {
                        showCardSheet = true
                    }
                    optionRow(icon: "banknote.fill", title: "Pagar na Entrega", subtitle: "Pague ao receber o pedido") {
                        Task { await changeToMethod("CASH") }
                    }
                }
                .padding(.horizontal, 20)
                .padding(.bottom, 32)
            }
        }
        .background(AppColors.backgroundLight)
        .sheet(isPresented: $showCardSheet) {
            let items = (try? JSONDecoder().decode([CreateOrderItemPayload].self, from: pixContext.itemsJSON.data(using: .utf8) ?? Data())) ?? []
            let cardCtx = CardPaymentContext.build(storeId: pixContext.storeId, total: pixContext.total, deliveryType: pixContext.deliveryType, profile: appState.profile, address: nil, items: items)
            ChangePaymentCardSheet(pixContext: pixContext, cardContext: cardCtx, savedCards: savedCards, appState: $appState) { _, _ in
                showCardSheet = false
                onConfirmed()
            }
        }
    }

    private func optionRow(icon: String, title: String, subtitle: String, action: @escaping () -> Void) -> some View {
        Button(action: action) {
            HStack(spacing: 14) {
                Image(systemName: icon).font(.system(size: 20)).foregroundStyle(AppColors.primary)
                    .frame(width: 44, height: 44).background(AppColors.brandSoft)
                    .clipShape(RoundedRectangle(cornerRadius: 10, style: .continuous))
                VStack(alignment: .leading, spacing: 3) {
                    Text(title).font(AppTypography.heading3).foregroundStyle(AppColors.textPrimary)
                    Text(subtitle).font(.caption).foregroundStyle(AppColors.textMuted)
                }
                Spacer()
                if isSubmitting { ProgressView().scaleEffect(0.8) }
                else { Image(systemName: "chevron.right").font(.system(size: 12, weight: .semibold)).foregroundStyle(AppColors.textMuted) }
            }
            .padding(14).background(AppColors.surface)
            .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
        }
        .buttonStyle(.plain).disabled(isSubmitting)
    }

    @MainActor
    private func changeToMethod(_ method: String) async {
        isSubmitting = true
        defer { isSubmitting = false }
        let payload = ChangePaymentMethodPayload(paymentMethod: method, clientCpfCnpj: nil, creditCard: nil, creditCardHolderInfo: nil, savedCardId: nil)
        do {
            let response = try await ApiService().changePaymentMethod(storeId: pixContext.storeId, orderId: pixContext.orderId, payload: payload)
            if response.error {
                SnackbarCenter.shared.show(title: response.message ?? "Não foi possível trocar o pagamento.", style: .error, icon: "xmark.octagon.fill", duration: 3.5)
                return
            }
            guard let result = response.result else { return }
            if method == "CASH" {
                SnackbarCenter.shared.show(title: "Pagamento alterado. Pague ao receber.", style: .success, icon: "checkmark.circle.fill", duration: 3.0)
                onConfirmed(); return
            }
            let pix = result.payment?.pix ?? result.paymentPayload
            if let copyPaste = pix?.copyPaste, copyPaste.isEmpty == false {
                let newCtx = PixPaymentContext(id: UUID().uuidString, orderId: pixContext.orderId, shortId: pixContext.shortId, storeId: pixContext.storeId, copyPaste: copyPaste, qrCodeImageBase64: pix?.qrCodeImage, expirationDate: pix?.expirationDate, total: pixContext.total, profileName: pixContext.profileName, profileEmail: pixContext.profileEmail, profilePhone: pixContext.profilePhone, addressZip: pixContext.addressZip, addressNumber: pixContext.addressNumber, deliveryType: pixContext.deliveryType, itemsJSON: pixContext.itemsJSON)
                SnackbarCenter.shared.show(title: "Novo QR Code gerado.", style: .success, icon: "qrcode", duration: 2.5)
                onChanged(newCtx)
            }
        } catch let error as NetworkError {
            let msg: String
            if case .httpError(_, let m) = error, let m, m.isEmpty == false { msg = m } else { msg = error.errorDescription ?? "Erro ao trocar pagamento." }
            SnackbarCenter.shared.show(title: msg, style: .error, icon: "xmark.octagon.fill", duration: 4.0)
        } catch {
            SnackbarCenter.shared.show(title: "Erro ao trocar pagamento.", style: .error, icon: "xmark.octagon.fill", duration: 3.0)
        }
    }
}

// MARK: - ChangePaymentCardSheet

struct ChangePaymentCardSheet: View {
    let pixContext: PixPaymentContext
    let cardContext: CardPaymentContext
    let savedCards: [SavedCard]
    @Binding var appState: AppState
    let onConfirmed: (String, String?) -> Void

    @Environment(\.dismiss) var dismiss
    @State var selectedCardId: String?
    @State var showNewCardForm = false
    @State var isSubmitting = false

    init(pixContext: PixPaymentContext, cardContext: CardPaymentContext, savedCards: [SavedCard], appState: Binding<AppState>, onConfirmed: @escaping (String, String?) -> Void) {
        self.pixContext = pixContext; self.cardContext = cardContext; self.savedCards = savedCards
        self._appState = appState; self.onConfirmed = onConfirmed
        _selectedCardId = State(initialValue: savedCards.first(where: { $0.isDefault })?.id ?? savedCards.first?.id)
    }

    var body: some View {
        VStack(spacing: 0) {
            HStack {
                Text("Cartão de Crédito").font(AppTypography.heading2).foregroundStyle(AppColors.textPrimary)
                Spacer()
                Button { dismiss() } label: {
                    Image(systemName: "xmark").font(.system(size: 12, weight: .bold)).foregroundStyle(AppColors.textMuted)
                        .frame(width: 30, height: 30).background(AppColors.surface).clipShape(Circle())
                }.buttonStyle(.plain)
            }
            .padding(.horizontal, 20).padding(.top, 20).padding(.bottom, 16)

            ScrollView(showsIndicators: false) {
                VStack(spacing: 16) {
                    if savedCards.isEmpty == false {
                        VStack(spacing: 0) {
                            ForEach(savedCards) { card in
                                Button { selectedCardId = card.id } label: {
                                    HStack(spacing: 12) {
                                        Image(systemName: "creditcard.fill").font(.system(size: 18)).foregroundStyle(AppColors.textPrimary)
                                            .frame(width: 44, height: 44).background(AppColors.backgroundLight)
                                            .clipShape(RoundedRectangle(cornerRadius: 10, style: .continuous))
                                        VStack(alignment: .leading, spacing: 3) {
                                            Text(card.displayLabel).font(AppTypography.heading3).foregroundStyle(AppColors.textPrimary)
                                            Text("Vence \(card.expiryLabel)").font(.caption).foregroundStyle(AppColors.textMuted)
                                        }
                                        Spacer()
                                        Circle().stroke(selectedCardId == card.id ? AppColors.tertiary : AppColors.textMuted.opacity(0.45), lineWidth: 2)
                                            .frame(width: 22, height: 22).background(Circle().fill(selectedCardId == card.id ? AppColors.tertiary : Color.clear))
                                    }.padding(14)
                                }.buttonStyle(.plain)
                                if card.id != savedCards.last?.id { Divider().padding(.horizontal, 14) }
                            }
                        }
                        .background(AppColors.surface)
                        .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))

                        if let selectedCardId {
                            PrimaryButton(title: isSubmitting ? "Processando..." : "Pagar com este Cartão") {
                                guard isSubmitting == false else { return }
                                Task { await changeToSavedCard(cardId: selectedCardId) }
                            }.disabled(isSubmitting)
                        }
                        Text("ou").font(AppTypography.caption).foregroundStyle(AppColors.textMuted).frame(maxWidth: .infinity, alignment: .center)
                    }
                    Button { showNewCardForm = true } label: {
                        HStack(spacing: 10) {
                            Image(systemName: "plus.circle.fill").font(.system(size: 18)).foregroundStyle(AppColors.primary)
                            Text("Novo cartão").font(AppTypography.heading3).foregroundStyle(AppColors.primary)
                            Spacer()
                        }
                        .padding(14).background(AppColors.surface)
                        .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))
                    }.buttonStyle(.plain)
                }
                .padding(.horizontal, 20).padding(.bottom, 32)
            }
        }
        .background(AppColors.backgroundLight)
        .sheet(isPresented: $showNewCardForm) {
            ChangePaymentNewCardView(pixContext: pixContext, appState: $appState) { orderId, shortId in
                showNewCardForm = false; onConfirmed(orderId, shortId)
            }
        }
    }

    @MainActor
    private func changeToSavedCard(cardId: String) async {
        isSubmitting = true; defer { isSubmitting = false }
        let payload = ChangePaymentMethodPayload(paymentMethod: "CREDIT_CARD", clientCpfCnpj: nil, creditCard: nil, creditCardHolderInfo: nil, savedCardId: cardId)
        do {
            let response = try await ApiService().changePaymentMethod(storeId: pixContext.storeId, orderId: pixContext.orderId, payload: payload)
            if response.error { SnackbarCenter.shared.show(title: response.message ?? "Pagamento recusado.", style: .error, icon: "xmark.octagon.fill", duration: 3.5); return }
            onConfirmed(pixContext.orderId, pixContext.shortId)
        } catch let error as NetworkError {
            let msg: String
            if case .httpError(_, let m) = error, let m, m.isEmpty == false { msg = m } else { msg = "Pagamento recusado." }
            SnackbarCenter.shared.show(title: msg, style: .error, icon: "xmark.octagon.fill", duration: 4.0)
        } catch { SnackbarCenter.shared.show(title: "Erro ao processar.", style: .error, icon: "xmark.octagon.fill", duration: 3.0) }
    }
}

// MARK: - ChangePaymentNewCardView

struct ChangePaymentNewCardView: View {
    let pixContext: PixPaymentContext
    @Binding var appState: AppState
    let onConfirmed: (String, String?) -> Void

    @Environment(\.dismiss) var dismiss
    @State var holderName: String
    @State var cardNumber = ""
    @State var expiry = ""
    @State var cvv = ""
    @State var cpf: String
    @State var saveCard = false
    @State var nickname = ""
    @State var isSubmitting = false

    init(pixContext: PixPaymentContext, appState: Binding<AppState>, onConfirmed: @escaping (String, String?) -> Void) {
        self.pixContext = pixContext; self._appState = appState; self.onConfirmed = onConfirmed
        _holderName = State(initialValue: appState.wrappedValue.profile.name)
        _cpf = State(initialValue: appState.wrappedValue.profile.cpf)
    }

    var canSubmit: Bool {
        holderName.trimmingCharacters(in: .whitespaces).isEmpty == false &&
        cardNumber.filter(\.isNumber).count >= 13 &&
        expiry.filter(\.isNumber).count == 6 &&
        cvv.filter(\.isNumber).count >= 3 &&
        cpf.filter(\.isNumber).count == 11
    }

    var body: some View {
        VStack(spacing: 0) {
            HStack {
                Text("Novo Cartão").font(AppTypography.heading2).foregroundStyle(AppColors.textPrimary)
                Spacer()
                Button { dismiss() } label: {
                    Image(systemName: "xmark").font(.system(size: 12, weight: .bold)).foregroundStyle(AppColors.textMuted)
                        .frame(width: 30, height: 30).background(AppColors.surface).clipShape(Circle())
                }.buttonStyle(.plain)
            }
            .padding(.horizontal, 20).padding(.top, 20).padding(.bottom, 16)

            ScrollView(showsIndicators: false) {
                VStack(spacing: 16) {
                    VStack(spacing: 10) {
                        cardField("Número do Cartão", placeholder: "0000 0000 0000 0000", text: $cardNumber).keyboardType(.numberPad)
                            .onChange(of: cardNumber) { _, v in
                                let d = String(v.filter(\.isNumber).prefix(16))
                                let m = stride(from: 0, to: d.count, by: 4).map { i -> String in let s = d.index(d.startIndex, offsetBy: i); let e = d.index(s, offsetBy: min(4, d.count - i)); return String(d[s..<e]) }.joined(separator: " ")
                                if m != v { cardNumber = m }
                            }
                        cardField("Nome no Cartão", placeholder: "Como impresso no cartão", text: $holderName)
                        HStack(spacing: 10) {
                            cardField("Validade", placeholder: "MM/AAAA", text: $expiry).keyboardType(.numberPad)
                                .onChange(of: expiry) { _, v in let d = String(v.filter(\.isNumber).prefix(6)); let m = d.count <= 2 ? d : "\(d.prefix(2))/\(d.dropFirst(2))"; if m != v { expiry = m } }
                            cardField("CVV", placeholder: "•••", text: $cvv).keyboardType(.numberPad)
                                .onChange(of: cvv) { _, v in let d = String(v.filter(\.isNumber).prefix(4)); if d != v { cvv = d } }
                        }
                        cardField("CPF do Titular", placeholder: "000.000.000-00", text: $cpf).keyboardType(.numberPad)
                            .onChange(of: cpf) { _, v in
                                let d = String(v.filter(\.isNumber).prefix(11))
                                let m: String
                                if d.count <= 3 { m = d } else if d.count <= 6 { m = "\(d.prefix(3)).\(d.dropFirst(3))" }
                                else if d.count <= 9 { m = "\(d.prefix(3)).\(d.dropFirst(3).prefix(3)).\(d.dropFirst(6))" }
                                else { m = "\(d.prefix(3)).\(d.dropFirst(3).prefix(3)).\(d.dropFirst(6).prefix(3))-\(d.dropFirst(9))" }
                                if m != v { cpf = m }
                            }
                    }
                    .padding(14).background(AppColors.surface)
                    .clipShape(RoundedRectangle(cornerRadius: AppLayout.radiusLG, style: .continuous))

                    PrimaryButton(title: isSubmitting ? "Processando..." : "Confirmar e Pagar") {
                        guard canSubmit, isSubmitting == false else { return }
                        Task { await submit() }
                    }.disabled(canSubmit == false || isSubmitting)
                }
                .padding(20)
            }
        }
        .background(AppColors.backgroundLight)
    }

    @MainActor
    private func submit() async {
        isSubmitting = true; defer { isSubmitting = false }
        let cleanCpf = cpf.filter(\.isNumber)
        let cleanNumber = cardNumber.filter(\.isNumber)
        let expiryDigits = expiry.filter(\.isNumber)
        let expiryMonth = String(expiryDigits.prefix(2))
        let yearPart = String(expiryDigits.dropFirst(2))
        let expiryYear = yearPart.count == 2 ? "20\(yearPart)" : yearPart
        let rawPhone = pixContext.profilePhone.filter(\.isNumber)
        let phone = rawPhone.hasPrefix("55") ? rawPhone : "55\(rawPhone)"

        let holderInfo = SaveCardHolderInfoPayload(name: pixContext.profileName.isEmpty ? holderName : pixContext.profileName, email: pixContext.profileEmail, cpfCnpj: cleanCpf, postalCode: (pixContext.addressZip ?? "").filter(\.isNumber), addressNumber: pixContext.addressNumber ?? "", phone: phone)
        let card = CreditCardOrderPayload(holderName: holderName, number: cleanNumber, expiryMonth: expiryMonth, expiryYear: expiryYear, ccv: cvv)
        let payload = ChangePaymentMethodPayload(paymentMethod: "CREDIT_CARD", clientCpfCnpj: cleanCpf, creditCard: card, creditCardHolderInfo: holderInfo, savedCardId: nil)

        if cleanCpf.count == 11 {
            appState.profile.cpf = cleanCpf
            Task<Void, Never> { do { _ = try await ApiService().updateProfileCpf(cpf: cleanCpf) } catch {} }
        }
        if saveCard {
            let sp = SaveCardPayload(creditCard: SaveCardCreditCardPayload(holderName: holderName, number: cleanNumber, expiryMonth: expiryMonth, expiryYear: expiryYear, ccv: cvv), creditCardHolderInfo: holderInfo, nickname: nickname.trimmingCharacters(in: .whitespaces).isEmpty ? nil : nickname, isDefault: false)
            Task<Void, Never> { do { _ = try await ApiService().saveCard(payload: sp) } catch {} }
        }

        do {
            let response = try await ApiService().changePaymentMethod(storeId: pixContext.storeId, orderId: pixContext.orderId, payload: payload)
            if response.error { SnackbarCenter.shared.show(title: response.message ?? "Pagamento recusado.", style: .error, icon: "xmark.octagon.fill", duration: 4.0); return }
            onConfirmed(pixContext.orderId, pixContext.shortId)
        } catch let error as NetworkError {
            let msg: String
            if case .httpError(_, let m) = error, let m, m.isEmpty == false { msg = m } else { msg = error.errorDescription ?? "Erro ao processar." }
            SnackbarCenter.shared.show(title: msg, style: .error, icon: "xmark.octagon.fill", duration: 5.0)
        } catch { SnackbarCenter.shared.show(title: "Erro ao processar pagamento.", style: .error, icon: "xmark.octagon.fill", duration: 3.0) }
    }

    private func cardField(_ label: String, placeholder: String, text: Binding<String>) -> some View {
        VStack(alignment: .leading, spacing: 6) {
            Text(label).font(AppTypography.caption).foregroundStyle(AppColors.textMuted)
            TextField(placeholder, text: text).appNoAutoCap()
                .padding(.horizontal, 12).frame(height: 46).background(AppColors.backgroundLight)
                .clipShape(RoundedRectangle(cornerRadius: 10, style: .continuous))
        }
    }
}