<?php

namespace App\Http\Controllers\Checkout;

use App\Http\Controllers\Controller;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\Validator;
use Illuminate\Validation\Rule;
use Illuminate\View\View;
use Lunar\Exceptions\Carts\CartException;
use Lunar\Exceptions\FingerprintMismatchException;
use Lunar\Facades\CartSession;
use Lunar\Models\Cart;
use Lunar\Models\Country;
use Lunar\Models\Order;
use Lunar\Models\State;
use Modules\Core\Cart\Services\CartService;
use Modules\Core\Checkout\Exceptions\InvalidShippingOptionException;
use Modules\Core\Checkout\Exceptions\TermsNotAcceptedException;
use Modules\Core\Checkout\Exceptions\UnknownPaymentTypeException;
use Modules\Core\Checkout\Services\CheckoutService;
use Modules\Core\Customer\Services\CustomerAccountService;
use Modules\Core\Payment\Enums\PaymentResultStatus;
use Modules\Core\Payment\Models\PaymentMethod;

/**
 * The checkout page — one page, sections (contact / billing / shipping /
 * shipping method), reviewed against boboko-core's CheckoutService. Stops
 * short of payment for this slice (see project memory).
 *
 * The address form and the shipping-method radios **autosave** — no submit
 * buttons. `saveAddress()` / `selectShippingOption()` are called by
 * bbk-checkout-form (debounced fetch) and return a JSON envelope of
 * server-rendered fragments (shipping options + order summary) plus any
 * field errors, rather than redirecting. Address validation is deliberately
 * lenient — nothing is rejected mid-typing; required-field enforcement is the
 * job of the (not-yet-built) "Continue to payment" gate.
 *
 * Guests type their email; the login tab links to the storefront's own
 * `login` route and back. Logged in: the email is the account's (forced in
 * saveAddress()), the first visit prefills addresses from the account
 * (prefillFromAccount()), and Lunar's Login listener has already attached the
 * cart, so the placed order lands in the account's history.
 *
 * Single-country store: STORE_COUNTRY_ISO3 fixes the country to Greece (hidden
 * field, forced server-side). Set it to null for the full country picker (the
 * portable path for a multi-country boboko store).
 */
class CheckoutController extends Controller
{
    private const STORE_COUNTRY_ISO3 = 'GRC';

    public function __construct(
        private readonly CartService $cart,
        private readonly CheckoutService $checkout,
        private readonly CustomerAccountService $account,
    ) {}

    public function show(string $locale): View
    {
        $cart = $this->cart->current();
        $lines = $cart ? $this->cart->activeLines($cart) : collect();
        $storeCountry = $this->storeCountry();

        $shippingOptions = collect();

        // Captured before prefillFromAccount(), which may recreate the address
        // row (dropping its shipping_option) — same reason as in saveAddress().
        $previousOption = $cart?->shippingAddress?->shipping_option;

        if ($cart && Auth::check()) {
            $cart = $this->prefillFromAccount($cart);

            // Nothing chosen on this cart yet: carry over the account's standing
            // opt-in (an explicit earlier choice, recorded with its own
            // timestamp/policy version). Never opts anyone in by default.
            if (! array_key_exists('recovery_consent', $cart->meta?->toArray() ?? [])
                && data_get($this->account->customer(Auth::user()), 'meta.recovery_consent')) {
                $cart = $this->checkout->setRecoveryConsent(true);
            }
        }

        if ($cart?->shippingAddress) {
            $shippingOptions = $this->syncShipping($cart, $previousOption);

            // Cart's CachesProperties::refresh() explicitly nulls total/
            // subTotal/shippingTotal/etc. back to their defaults — every
            // Lunar call site pairs it with recalculate() for exactly that
            // reason. Bare refresh() here was leaving $cart->total null on
            // reload, which fed a 0 amount straight into the Stripe Element.
            $cart->refresh()->recalculate();
        }

        $paymentMethods = $this->checkout->getPaymentMethods();

        // Nothing checked yet (fresh cart), or the shopper's earlier pick is
        // no longer offered (method disabled/removed since) — auto-select
        // the first one, same as a manual click would, so the payment
        // section (and the Stripe Element mounting under it) isn't sitting
        // inert behind an unchecked radio. A still-valid previous choice is
        // left alone.
        $firstMethod = $paymentMethods->first();

        if ($cart && $firstMethod && ! $paymentMethods->contains('type', data_get($cart, 'meta.payment_method'))) {
            $cart = $this->checkout->selectPaymentMethod($firstMethod->type);
        }

        return view('checkout::page', [
            'cart' => $cart,
            'lines' => $lines,
            'billingAddress' => $cart?->billingAddress,
            'shippingAddress' => $cart?->shippingAddress,
            'shippingOptions' => $shippingOptions,
            'paymentMethods' => $paymentMethods,
            'shipToBilling' => (bool) data_get($cart, 'meta.ship_to_billing', true),
            'wantsInvoice' => (bool) data_get($cart, 'meta.wants_invoice', false),
            'storeCountry' => $storeCountry,
            'countries' => $storeCountry
                ? collect()
                : Country::orderBy('name')->get(['id', 'name']),
            'regions' => $storeCountry
                ? State::where('country_id', $storeCountry->id)->orderBy('name')->get(['id', 'name'])
                : collect(),
        ]);
    }

    public function saveAddress(string $locale, Request $request): JsonResponse
    {
        $storeCountry = $this->storeCountry();
        $sameAsBilling = $request->boolean('same_as_billing');

        // Only the fields shipping rates resolve against — if none of these
        // changed (shopper edited their name, phone, email, …) there's no point
        // re-quoting shipping or re-rendering the summary.
        $addressBefore = $this->cart->current()?->shippingAddress;
        $rateKeyBefore = $addressBefore?->only(['postcode', 'state', 'country_id']);

        // setShippingAddress() below always deletes + recreates this row (see
        // syncShipping()'s docblock) — capture what was selected NOW, before
        // it's gone, so it can be carried forward onto the fresh row.
        $previousOption = $addressBefore?->shipping_option;

        $stateRule = $storeCountry
            ? ['nullable', 'string', Rule::exists((new State)->getTable(), 'name')->where('country_id', $storeCountry->id)]
            : ['nullable', 'string', 'max:255'];
        $countryRule = $storeCountry
            ? ['nullable']
            : ['nullable', 'integer', 'exists:'.(new Country)->getTable().',id'];

        // Lenient — only format checks. Anything that fails is simply left out
        // of what gets persisted, and reported back for inline display.
        $validator = Validator::make($request->all(), [
            'contact_email' => ['nullable', 'email'],

            'billing_first_name' => ['nullable', 'string', 'max:255'],
            'billing_last_name' => ['nullable', 'string', 'max:255'],
            'billing_company_name' => ['nullable', 'string', 'max:255'],
            'billing_tax_identifier' => ['nullable', 'string', 'max:255'],
            'billing_line_one' => ['nullable', 'string', 'max:255'],
            'billing_city' => ['nullable', 'string', 'max:255'],
            'billing_state' => $stateRule,
            'billing_postcode' => ['nullable', 'string', 'max:20'],
            'billing_country_id' => $countryRule,
            'billing_contact_phone' => ['nullable', 'string', 'max:50'],

            'shipping_first_name' => ['nullable', 'string', 'max:255'],
            'shipping_last_name' => ['nullable', 'string', 'max:255'],
            'shipping_line_one' => ['nullable', 'string', 'max:255'],
            'shipping_city' => ['nullable', 'string', 'max:255'],
            'shipping_state' => $stateRule,
            'shipping_postcode' => ['nullable', 'string', 'max:20'],
            'shipping_country_id' => $countryRule,
            'shipping_contact_phone' => ['nullable', 'string', 'max:50'],
            'shipping_delivery_instructions' => ['nullable', 'string', 'max:1000'],
        ]);

        $errors = $validator->errors()->toArray();
        $data = $validator->valid();

        // Logged in: the order email is always the account's. It isn't a field
        // on the page then, and a submitted value isn't trusted.
        if ($user = Auth::user()) {
            $data['contact_email'] = $user->email;
        }

        $billingCountryId = $storeCountry?->id ?? ($data['billing_country_id'] ?? null);
        $shippingCountryId = $storeCountry?->id ?? ($data['shipping_country_id'] ?? $billingCountryId);

        // Company/ΑΦΜ only count when "I want an invoice" is ticked; the fields
        // stay in the DOM (just hidden) when it isn't, so ignore what they send.
        $wantsInvoice = $request->boolean('wants_invoice');

        $billing = [
            'first_name' => $data['billing_first_name'] ?? null,
            'last_name' => $data['billing_last_name'] ?? null,
            'company_name' => $wantsInvoice ? ($data['billing_company_name'] ?? null) : null,
            'tax_identifier' => $wantsInvoice ? ($data['billing_tax_identifier'] ?? null) : null,
            'line_one' => $data['billing_line_one'] ?? null,
            'city' => $data['billing_city'] ?? null,
            'state' => $data['billing_state'] ?? null,
            'postcode' => $data['billing_postcode'] ?? null,
            'country_id' => $billingCountryId,
            'contact_email' => $data['contact_email'] ?? null,
            'contact_phone' => $data['billing_contact_phone'] ?? null,
        ];

        $shipping = $sameAsBilling
            ? [
                ...array_diff_key($billing, ['company_name' => 1, 'tax_identifier' => 1]),
                'delivery_instructions' => $data['shipping_delivery_instructions'] ?? null,
            ]
            : [
                'first_name' => $data['shipping_first_name'] ?? null,
                'last_name' => $data['shipping_last_name'] ?? null,
                'line_one' => $data['shipping_line_one'] ?? null,
                'city' => $data['shipping_city'] ?? null,
                'state' => $data['shipping_state'] ?? null,
                'postcode' => $data['shipping_postcode'] ?? null,
                'country_id' => $shippingCountryId,
                'contact_email' => $data['contact_email'] ?? null,
                'contact_phone' => $data['shipping_contact_phone'] ?? null,
                'delivery_instructions' => $data['shipping_delivery_instructions'] ?? null,
            ];

        $this->checkout->setBillingAddress($billing);
        $cart = $this->checkout->setShippingAddress($shipping);

        $cart->meta = [
            ...($cart->meta?->toArray() ?? []),
            'ship_to_billing' => $sameAsBilling,
            'wants_invoice' => $wantsInvoice,
        ];
        $cart->save();

        // Abandoned-cart-recovery opt-in — boboko-core owns the record (bool +
        // timestamp + policy version on Cart::meta, RecoveryConsentSet event).
        // Deliberately its own scope, not merged with any future newsletter opt-in.
        $this->checkout->setRecoveryConsent($request->boolean('recovery_consent'));

        if (Auth::check()) {
            $this->account->setRecoveryConsent(Auth::user(), $request->boolean('recovery_consent'));
        }

        $rateKeyAfter = $cart->shippingAddress?->only(['postcode', 'state', 'country_id']);
        $rateChanged = $rateKeyAfter != $rateKeyBefore;

        // setShippingAddress() above always deletes and recreates the
        // CartAddress row (Lunar's AddAddress action), which drops whatever
        // shipping_option was previously selected — regardless of whether the
        // rate-determining fields actually changed. So this always has to run
        // to restore/re-validate it, even on a save that only touched e.g. the
        // phone number. Only the fragment RE-RENDER is skippable when nothing
        // rate-relevant moved — the re-select itself is not optional.
        $options = $this->syncShipping($cart, $previousOption);

        if (! $rateChanged) {
            return $this->fragments($cart, null, $errors);
        }

        return $this->fragments($cart, $options, $errors);
    }

    public function selectShippingOption(string $locale, Request $request): JsonResponse
    {
        $identifier = (string) $request->input('shipping_option');

        try {
            $this->checkout->selectShippingOption($identifier);
        } catch (InvalidShippingOptionException) {
            // Re-render with whatever is currently valid; no hard error surfaced.
        }

        $cart = $this->cart->current();
        $options = $cart?->shippingAddress
            ? $this->checkout->getShippingOptions()
            : collect();

        return $this->fragments($cart, $options);
    }

    /**
     * Autosave-select a payment method (radio change). Persists it via
     * CheckoutService (which also records it on Cart::meta and re-snapshots
     * the fingerprint) so ApplyCashOnDeliveryFee etc. show in the summary.
     */
    public function selectPaymentMethod(string $locale, Request $request): JsonResponse
    {
        $type = (string) $request->input('payment_type');

        try {
            $this->checkout->selectPaymentMethod($type);
        } catch (UnknownPaymentTypeException) {
            // Radio value out of sync with what's offered — ignore, the summary
            // just won't reflect a method fee. place-order re-checks properly.
        }

        return response()->json([
            'summaryHtml' => view('checkout::partials.cart-body')->render(),
        ]);
    }

    /**
     * The real submit — the hard gate. Re-selects the payment method (fresh
     * fingerprint), then hands off to CheckoutService::initiatePayment(), which
     * creates the draft order, records terms acceptance, and charges the driver.
     * Returns JSON the bbk-payment controller routes on:
     *   { redirect }                       — placed, go to confirmation
     *   { status: 'pending', clientSecret }— 3-D Secure; client does handleNextAction then polls
     *   { status: 'failed', message }      — declined
     *   { status: 'invalid'|'stale', ... } — cart incomplete / changed since selection
     */
    public function placeOrder(string $locale, Request $request): JsonResponse
    {
        if (! $request->boolean('terms_accepted')) {
            return response()->json(['error' => __('checkout.page.terms_required')], 422);
        }

        try {
            $this->checkout->selectPaymentMethod((string) $request->input('payment_type'));
        } catch (UnknownPaymentTypeException) {
            return response()->json(['error' => __('checkout.page.choose_payment_method')], 422);
        }

        $cart = $this->cart->current();

        // Captured now, before initiatePayment() can place the order — Lunar's
        // CartSessionManager::fetchOrCreate() silently swaps the session onto a
        // BRAND NEW empty cart the moment the current one hasCompletedOrders()
        // (i.e. has an order with placed_at set), which happens synchronously
        // for an immediately-captured payment. Any later $this->cart->current()
        // call in this same flow (here, or in a subsequent orderStatus() poll
        // once the 3-D Secure webhook sets placed_at) would then resolve to
        // that fresh, order-less cart instead of the one that was just placed.
        // Storing the real cart id ourselves, under our own session key,
        // sidesteps CartSession entirely for the rest of the placement flow.
        session(['checkout.cart_id' => $cart?->id]);

        // Lunar's own ValidateCartForOrderCreation (order_create validator)
        // never checks for this — an empty cart with a valid billing address
        // sails straight through it and would place a real, zero-line order.
        // The disabled "place order" button is only the client-side half of
        // this fix; this is the half that actually matters.
        if ($cart === null || $this->cart->activeLines($cart)->isEmpty()) {
            return response()->json([
                'status' => 'invalid',
                'message' => __('checkout.page.cart_empty'),
            ], 422);
        }

        // Lenient autosave never requires these; this is the gate.
        if (data_get($cart, 'meta.wants_invoice')
            && (blank($cart->billingAddress?->company_name) || blank($cart->billingAddress?->tax_identifier))) {
            return response()->json([
                'status' => 'invalid',
                'message' => __('checkout.page.invoice_required'),
            ], 422);
        }

        // Same check Lunar's own ValidateCartForOrderCreation runs inside
        // initiatePayment() (a product unpublished/deleted after it was
        // added to the cart) — checked here first so the shopper is told
        // which product is the problem, rather than falling into the
        // catch-all "complete your billing/shipping details" message below,
        // which is what actually happened and is generic to every
        // CartException reason, misleading when the real cause is a line,
        // not an address.
        $unavailableLines = $this->cart->activeLines($cart)->filter(
            fn ($line) => ! $line->purchasable || ! $line->purchasable->isPurchasable(),
        );

        if ($unavailableLines->isNotEmpty()) {
            $names = $unavailableLines
                ->map(fn ($line) => $line->purchasable?->product?->translateAttribute('name') ?? $line->purchasable?->getIdentifier())
                ->filter()
                ->implode(', ');

            return response()->json([
                'status' => 'invalid',
                'message' => __('checkout.page.cart_line_unavailable', ['name' => $names]),
            ], 422);
        }

        // The one incomplete-cart case worth a specific message + pointing the
        // shopper at the right section: a region resolving 2+ methods needs an
        // explicit pick (no auto-select), easy to miss since nothing else on
        // the page demands it. Everything else CartException catches below.
        if ($cart?->shippingAddress && ! $cart->shippingAddress->shipping_option) {
            return response()->json([
                'status' => 'invalid',
                'message' => __('checkout.page.shipping_method_required'),
                'field' => 'shipping_option',
            ], 422);
        }

        $fingerprint = (string) ($cart?->meta['checkout_fingerprint'] ?? '');

        $data = $request->filled('payment_method')
            ? ['payment_method' => (string) $request->input('payment_method')]
            : [];

        try {
            $result = $this->checkout->initiatePayment(
                $fingerprint,
                termsAccepted: true,
                policyVersion: (string) config('legal.terms_version'),
                data: $data,
            );
        } catch (FingerprintMismatchException) {
            return response()->json(['status' => 'stale', 'message' => __('checkout.page.payment_cart_changed')], 409);
        } catch (CartException $e) {
            return response()->json([
                'status' => 'invalid',
                'message' => __('checkout.page.payment_incomplete_details'),
                'errors' => collect($e->errors()->toArray())->map(fn ($m) => is_array($m) ? ($m[0] ?? null) : $m)->all(),
            ], 422);
        } catch (TermsNotAcceptedException) {
            return response()->json(['error' => __('checkout.page.terms_required')], 422);
        }

        // Pending with no continuation (cash-on-delivery, or any other
        // deferred/offline method) means CheckoutService::initiatePayment()
        // already created the placed order — money just hasn't changed
        // hands yet. Only a Pending WITH a continuation (Stripe's client
        // secret) means the shopper still has something to do before the
        // order exists as far as the storefront is concerned.
        return match (true) {
            $result->status === PaymentResultStatus::Succeeded => $this->orderPlacedResponse($locale),
            $result->status === PaymentResultStatus::Pending && $result->continuation === null => $this->orderPlacedResponse($locale),
            $result->status === PaymentResultStatus::Pending => response()->json([
                'status' => 'pending',
                'clientSecret' => $result->continuation?->value,
            ]),
            default => response()->json([
                'status' => 'failed',
                'message' => $result->failureReason ?: __('checkout.page.payment_failed'),
                'retriable' => $result->retriable,
            ], 422),
        };
    }

    /**
     * Poll target for the 3-D Secure path: has the webhook placed the order yet?
     * boboko-core's StripeWebhookController -> handleCallback -> PaymentCaptured
     * -> ApplyResolvedPaymentStatus sets placed_at.
     */
    public function orderStatus(string $locale): JsonResponse
    {
        $order = $this->placedOrder();

        if (! $order) {
            return response()->json(['placed' => false]);
        }

        session(['checkout.order_id' => $order->id]);
        CartSession::forget();

        return response()->json(['placed' => true, 'redirect' => route('checkout.confirmation', $locale)]);
    }

    public function confirmation(string $locale): View|RedirectResponse
    {
        $orderId = session('checkout.order_id');

        $order = $orderId
            ? Order::with(['lines.purchasable.product', 'shippingAddress', 'billingAddress'])->find($orderId)
            : null;

        if (! $order) {
            return redirect()->route('products', $locale);
        }

        // Looked up by type rather than a stored relation — the method may since
        // have been disabled/deleted, but the order still needs to show what was
        // actually used at the time.
        $paymentMethodName = PaymentMethod::where('type', $order->meta['payment_method'] ?? null)
            ->first()
            ?->translate('name');

        return view('checkout::confirmation', [
            'order' => $order,
            'paymentMethodName' => $paymentMethodName,
        ]);
    }

    private function orderPlacedResponse(string $locale): JsonResponse
    {
        if ($order = $this->placedOrder()) {
            session(['checkout.order_id' => $order->id]);
        }

        CartSession::forget();

        return response()->json(['redirect' => route('checkout.confirmation', $locale)]);
    }

    private function placedOrder(): ?Order
    {
        $cartId = session('checkout.cart_id');

        if ($cartId === null) {
            return null;
        }

        return Order::where('cart_id', $cartId)
            ->whereNotNull('placed_at')
            ->latest('placed_at')
            ->first();
    }

    /**
     * Re-resolve shipping options for the cart's current address and keep the
     * selection sane: auto-select when exactly one resolves, or carry a
     * previous pick forward when it's still among the resolved options.
     *
     * $previousOption must be captured by the CALLER before setShippingAddress()
     * runs — Lunar's AddAddress action always deletes and recreates the
     * CartAddress row on every save (see saveAddress()), so by the time this
     * runs, $address->shipping_option is unconditionally null regardless of
     * what was selected a moment ago. There is nothing meaningful left to read
     * off $address itself; $previousOption is the only source of truth for
     * "what was chosen before this save wiped the row." show() passes the
     * address's own (not-just-wiped) current value, since nothing recreated
     * anything in that path.
     *
     * Always (re-)applies the resolved target via selectShippingOption() rather
     * than comparing against the (always-blank, post-recreation) current value
     * — the fresh row needs the write regardless of whether the decision
     * "which option" actually changed.
     *
     * @return Collection<int, \Lunar\DataTypes\ShippingOption>
     */
    private function syncShipping(Cart $cart, ?string $previousOption): Collection
    {
        if (! $cart->shippingAddress) {
            return collect();
        }

        $options = $this->checkout->getShippingOptions();

        $target = match (true) {
            $options->count() === 1 => $options->first()->identifier,
            $previousOption !== null && $options->contains(fn ($option) => $option->identifier === $previousOption) => $previousOption,
            default => null,
        };

        if ($target !== null) {
            try {
                $this->checkout->selectShippingOption($target);
            } catch (InvalidShippingOptionException) {
                // $target came from $options itself — shouldn't happen, stay defensive
            }
        }

        return $options;
    }

    /**
     * $options === null means "nothing money-relevant changed" — acknowledge the
     * save (and any field errors) without re-rendering the shipping options or
     * the order summary, so a plain name/phone edit is a cheap round-trip.
     */
    private function fragments(?Cart $cart, ?Collection $options, array $errors = []): JsonResponse
    {
        return response()->json([
            'errors' => collect($errors)
                ->map(fn ($messages) => is_array($messages) ? ($messages[0] ?? null) : $messages)
                ->all(),
            'shippingOptionsHtml' => $options === null ? null : view('checkout::partials.shipping-options', [
                'shippingAddress' => $cart?->shippingAddress,
                'shippingOptions' => $options,
            ])->render(),
            // Composer (CheckoutModuleServiceProvider) fills $cart / $lines.
            'summaryHtml' => $options === null ? null : view('checkout::partials.cart-body')->render(),
        ]);
    }

    /**
     * Logged-in shopper: fills any BLANK cart address field from the account
     * (name, saved default address, phone, email), on every checkout load, so
     * an account filled in after checkout started still shows up. Never
     * overwrites anything already in the cart.
     *
     * Company/ΑΦΜ (and ticking "I want an invoice") only on the first pass
     * (meta.account_prefilled): someone who then clears them or unticks the
     * box for this order shouldn't get them back on the next reload.
     *
     * Writes only when something actually changes, so a normal reload costs
     * nothing extra.
     */
    private function prefillFromAccount(Cart $cart): Cart
    {
        $user = Auth::user();
        $customer = $this->account->customer($user);
        $addresses = collect($this->account->addresses($user));
        $saved = $addresses->firstWhere('shipping_default', true) ?? $addresses->first();
        $firstPass = ! data_get($cart, 'meta.account_prefilled');

        $fromAccount = array_filter([
            'first_name' => $customer?->first_name ?: $saved?->first_name,
            'last_name' => $customer?->last_name ?: $saved?->last_name,
            'line_one' => $saved?->line_one,
            'city' => $saved?->city,
            'state' => $saved?->state,
            'postcode' => $saved?->postcode,
            'country_id' => $this->storeCountry()?->id ?? $saved?->country_id,
            'contact_email' => $user->email,
            'contact_phone' => $saved?->contact_phone,
        ], 'filled');

        $invoice = $firstPass
            ? array_filter([
                'company_name' => $customer?->company_name,
                'tax_identifier' => $customer?->tax_identifier,
            ], 'filled')
            : [];

        $fields = ['first_name', 'last_name', 'company_name', 'tax_identifier', 'line_one', 'city',
            'state', 'postcode', 'country_id', 'contact_email', 'contact_phone'];

        $fillBlanks = function (?array $current, array $values) {
            $current ??= [];

            foreach ($values as $key => $value) {
                if (blank($current[$key] ?? null)) {
                    $current[$key] = $value;
                }
            }

            return $current;
        };

        $billingBefore = $cart->billingAddress?->only($fields);
        $billing = $fillBlanks($billingBefore, [...$fromAccount, ...$invoice]);

        // Shipping has no company/ΑΦΜ (same shape saveAddress() writes).
        $shipToBilling = (bool) data_get($cart, 'meta.ship_to_billing', true);
        $shippingFields = [...array_diff($fields, ['company_name', 'tax_identifier']), 'delivery_instructions'];

        $shippingBefore = $cart->shippingAddress?->only($shippingFields);
        $shipping = $shipToBilling
            ? [
                ...array_diff_key($billing, ['company_name' => 1, 'tax_identifier' => 1]),
                'delivery_instructions' => $shippingBefore['delivery_instructions'] ?? null,
            ]
            : $fillBlanks($shippingBefore, $fromAccount);

        if ($billing != ($billingBefore ?? []) || $shipping != ($shippingBefore ?? [])) {
            $this->checkout->setBillingAddress($billing);
            $cart = $this->checkout->setShippingAddress($shipping);
        }

        if ($firstPass) {
            $cart->meta = [
                ...($cart->meta?->toArray() ?? []),
                'account_prefilled' => true,
                'wants_invoice' => (bool) data_get($cart, 'meta.wants_invoice') || $invoice !== [],
            ];
            $cart->save();
        }

        return $cart;
    }

    private function storeCountry(): ?Country
    {
        if (self::STORE_COUNTRY_ISO3 === null) {
            return null;
        }

        return Country::where('iso3', self::STORE_COUNTRY_ISO3)->first();
    }
}