<?php
declare(strict_types=1);

namespace Esun\EmailPreview\Model;

use Magento\Email\Model\TemplateFactory;
use Magento\Framework\App\Area;
use Magento\Framework\App\Config\ScopeConfigInterface;
use Magento\Framework\DataObject;
use Magento\Framework\Exception\LocalizedException;
use Magento\Framework\Mail\Template\TransportBuilder;
use Magento\Payment\Helper\Data as PaymentHelper;
use Magento\Sales\Model\Order;
use Magento\Sales\Model\Order\Address\Renderer as AddressRenderer;
use Magento\Sales\Model\OrderFactory;
use Magento\Sales\Model\ResourceModel\Order\Creditmemo\CollectionFactory as CreditmemoCollectionFactory;
use Magento\Sales\Model\ResourceModel\Order\Invoice\CollectionFactory as InvoiceCollectionFactory;
use Magento\Sales\Model\ResourceModel\Order\Shipment\CollectionFactory as ShipmentCollectionFactory;
use Magento\Store\Model\ScopeInterface;
use Magento\Store\Model\StoreManagerInterface;

class PreviewService
{
    public function __construct(
        private readonly StoreManagerInterface $storeManager,
        private readonly ScopeConfigInterface $scopeConfig,
        private readonly TemplateFactory $templateFactory,
        private readonly TransportBuilder $transportBuilder,
        private readonly OrderFactory $orderFactory,
        private readonly ShipmentCollectionFactory $shipments,
        private readonly CreditmemoCollectionFactory $creditmemos,
        private readonly InvoiceCollectionFactory $invoices,
        private readonly AddressRenderer $addressRenderer,
        private readonly PaymentHelper $paymentHelper
    ) {}

    public function render(array $request): array
    {
        [$identifier, $variables, $storeId] = $this->prepare($request);
        $template = $this->templateFactory->create();
        $template->setDesignConfig(['area' => Area::AREA_FRONTEND, 'store' => $storeId]);
        $template->setId($identifier);
        $template->setVars($variables);
        $html = $template->processTemplate();
        return ['html' => $html, 'subject' => $template->getProcessedTemplateSubject($variables)];
    }

    public function send(array $request, string $recipient): void
    {
        if (!filter_var($recipient, FILTER_VALIDATE_EMAIL)) {
            throw new LocalizedException(__('Enter a valid test recipient email address.'));
        }
        [$identifier, $variables, $storeId] = $this->prepare($request);
        $this->transportBuilder
            ->setTemplateIdentifier($identifier)
            ->setTemplateOptions(['area' => Area::AREA_FRONTEND, 'store' => $storeId])
            ->setTemplateVars($variables)
            ->setFromByScope('general', $storeId)
            ->addTo($recipient)
            ->getTransport()->sendMessage();
    }

    private function prepare(array $request): array
    {
        $type = (string)($request['type'] ?? '');
        if (!isset(TemplateTypes::TYPES[$type])) {
            throw new LocalizedException(__('Select a supported email type.'));
        }
        $storeId = (int)($request['store_id'] ?? 0);
        $store = $this->storeManager->getStore($storeId);
        $definition = TemplateTypes::TYPES[$type];
        $identifier = '';
        $variables = [];

        if (in_array($type, ['order', 'order_update', 'invoice', 'invoice_update', 'shipment', 'shipment_update', 'creditmemo', 'creditmemo_update'], true)) {
            $order = $this->loadOrder((string)($request['increment_id'] ?? ''), $storeId);
            if ($identifier === '') {
                $default = $order->getCustomerIsGuest() && isset($definition['guest']) ? $definition['guest'] : $definition['template'];
                $configPath = $order->getCustomerIsGuest() ? str_replace('/template', '/guest_template', $definition['config']) : $definition['config'];
                $identifier = (string)($this->scopeConfig->getValue($configPath, ScopeInterface::SCOPE_STORE, $storeId) ?: $default);
            }
            $variables = $this->orderVariables($order);
            $variables['comment'] = 'This is a preview of the latest customer notification.';
            if (in_array($type, ['invoice', 'invoice_update'], true)) {
                $entity = $this->invoices->create()->setOrderFilter($order)->setOrder('entity_id', 'DESC');
                $number = trim((string)($request['entity_id'] ?? ''));
                if ($number !== '') { $entity->addFieldToFilter('increment_id', $number); }
                $invoice = $entity->getFirstItem();
                if (!$invoice->getId()) { throw new LocalizedException(__('No invoice was found for this order.')); }
                $variables += ['invoice' => $invoice, 'invoice_id' => $invoice->getId()];
            } elseif (in_array($type, ['shipment', 'shipment_update'], true)) {
                $entity = $this->shipments->create()->setOrderFilter($order)->setOrder('entity_id', 'DESC');
                $number = trim((string)($request['entity_id'] ?? ''));
                if ($number !== '') { $entity->addFieldToFilter('increment_id', $number); }
                $shipment = $entity->getFirstItem();
                if (!$shipment->getId()) { throw new LocalizedException(__('No shipment was found for this order.')); }
                $variables += ['shipment' => $shipment, 'shipment_id' => $shipment->getId(), 'comment' => ''];
            } elseif (in_array($type, ['creditmemo', 'creditmemo_update'], true)) {
                $entity = $this->creditmemos->create()->setOrderFilter($order)->setOrder('entity_id', 'DESC');
                $number = trim((string)($request['entity_id'] ?? ''));
                if ($number !== '') { $entity->addFieldToFilter('increment_id', $number); }
                $creditmemo = $entity->getFirstItem();
                if (!$creditmemo->getId()) { throw new LocalizedException(__('No credit memo was found for this order.')); }
                $variables += ['creditmemo' => $creditmemo, 'creditmemo_id' => $creditmemo->getId(), 'comment' => ''];
            }
        } else {
            if ($identifier === '') {
                $identifier = (string)($this->scopeConfig->getValue($definition['config'], ScopeInterface::SCOPE_STORE, $storeId) ?: $definition['template']);
            }
            $customer = new DataObject([
                'id' => 0, 'firstname' => 'Preview', 'lastname' => 'Customer',
                'name' => 'Preview Customer', 'email' => 'customer@example.com',
                'rp_token' => 'preview-only-token'
            ]);
            $customer->setData('confirmation', 'preview-confirmation-key');
            $variables = ['store' => $store, 'customer' => $customer, 'back_url' => ''];
        }
        return [$identifier, $variables + $this->storeVariables($storeId), $storeId];
    }

    private function loadOrder(string $incrementId, int $storeId): Order
    {
        if (trim($incrementId) === '') { throw new LocalizedException(__('Enter an order number for this email type.')); }
        $order = $this->orderFactory->create()->loadByIncrementId(trim($incrementId));
        if (!$order->getId() || (int)$order->getStoreId() !== $storeId) { throw new LocalizedException(__('The order was not found in the selected Store View.')); }
        return $order;
    }

    private function orderVariables(Order $order): array
    {
        return [
            'order' => $order, 'order_id' => $order->getId(), 'billing' => $order->getBillingAddress(),
            'payment_html' => $this->paymentHelper->getInfoBlockHtml($order->getPayment(), (int)$order->getStoreId()),
            'store' => $order->getStore(),
            'formattedShippingAddress' => $order->getIsVirtual() ? '' : $this->addressRenderer->format($order->getShippingAddress(), 'html'),
            'formattedBillingAddress' => $this->addressRenderer->format($order->getBillingAddress(), 'html'),
            'created_at_formatted' => $order->getCreatedAtFormatted(2),
            'order_data' => new DataObject(['customer_name' => $order->getCustomerName(), 'is_not_virtual' => $order->getIsNotVirtual(), 'email_customer_note' => $order->getEmailCustomerNote(), 'frontend_status_label' => $order->getFrontendStatusLabel()])
        ];
    }

    private function storeVariables(int $storeId): array
    {
        return [
            'store_email' => (string)$this->scopeConfig->getValue('trans_email/ident_general/email', ScopeInterface::SCOPE_STORE, $storeId),
            'store_phone' => (string)$this->scopeConfig->getValue('general/store_information/phone', ScopeInterface::SCOPE_STORE, $storeId),
            'store_hours' => (string)$this->scopeConfig->getValue('general/store_information/hours', ScopeInterface::SCOPE_STORE, $storeId),
        ];
    }
}