<?php
class ControllerExtensionModuleReverb extends Controller {

    // -------------------------------------------------------------------------
    // Webhook receiver
    // URL: index.php?route=extension/module/reverb/webhook
    // -------------------------------------------------------------------------

    public function webhook() {
        $raw = file_get_contents('php://input');

        // Validate Reverb signature if a secret is configured
        $secret = $this->config->get('module_reverb_webhook_secret');
        if ($secret) {
            $signature = $_SERVER['HTTP_REVERB_SIGNATURE'] ?? '';
            if (!hash_equals(hash_hmac('sha256', $raw, $secret), $signature)) {
                http_response_code(401);
                exit('Unauthorized');
            }
        }

        $payload = json_decode($raw, true);
        if (!$payload || empty($payload['event'])) {
            http_response_code(400);
            exit('Bad Request');
        }

        $this->load->model('extension/module/reverb');

        try {
            switch ($payload['event']) {
                case 'listing/update':
                    $this->handleListingUpdate($payload);
                    break;

                case 'order/create':
                    $this->handleOrderCreate($payload);
                    break;

                default:
                    // Unknown event — acknowledge silently
                    break;
            }
        } catch (Exception $e) {
            $this->model_extension_module_reverb->log(0, 'pull', 'error', 'Webhook error: ' . $e->getMessage());
            http_response_code(500);
            exit('Internal Error');
        }

        http_response_code(200);
        exit('OK');
    }

    // -------------------------------------------------------------------------
    // Cron endpoint — polls Reverb for updates (fallback when webhooks not used)
    // URL: index.php?route=extension/module/reverb/cron&cron_token=SECRET
    // -------------------------------------------------------------------------

    public function cron() {
        $cron_token = $this->config->get('module_reverb_cron_token');
        if ($cron_token && ($this->request->get['cron_token'] ?? '') !== $cron_token) {
            http_response_code(403);
            exit('Forbidden');
        }

        $this->load->model('extension/module/reverb');

        $direction = $this->config->get('module_reverb_sync_direction') ?? 'push';

        if ($direction === 'both') {
            $this->pollListingUpdates();
            $this->pollOrders();
        }

        // Push any products that haven't been synced yet
        $this->pushPendingProducts();

        exit('Done');
    }

    // -------------------------------------------------------------------------
    // Internal: listing update (Reverb → OpenCart)
    // -------------------------------------------------------------------------

    private function handleListingUpdate(array $payload) {
        $listing = $payload['listing'] ?? [];
        if (empty($listing['id'])) {
            return;
        }

        $listing_id = (string)$listing['id'];

        $query = $this->db->query("
            SELECT product_id FROM `" . DB_PREFIX . "reverb_product_map`
            WHERE reverb_listing_id = '" . $this->db->escape($listing_id) . "'
        ");

        if (!$query->num_rows) {
            return;
        }

        $product_id = (int)$query->row['product_id'];

        require_once(DIR_SYSTEM . 'library/reverb/ProductMapper.php');
        $updates = ProductMapper::fromReverb($listing);

        if (!empty($updates)) {
            $this->load->model('catalog/product');
            $this->model_catalog_product->editProduct($product_id, $updates);
            $this->model_extension_module_reverb->log($product_id, 'pull', 'success', 'Updated from Reverb listing ' . $listing_id);
        }
    }

    // -------------------------------------------------------------------------
    // Internal: new order (Reverb → OpenCart)
    // -------------------------------------------------------------------------

    private function handleOrderCreate(array $payload) {
        $reverb_order = $payload['order'] ?? [];
        if (empty($reverb_order['order_number'])) {
            return;
        }

        $order_number = $reverb_order['order_number'];

        // Check for duplicate — avoid creating the same order twice
        $check = $this->db->query("
            SELECT order_id FROM `" . DB_PREFIX . "order`
            WHERE comment LIKE '%" . $this->db->escape('Reverb Order #' . $order_number) . "%'
            LIMIT 1
        ");
        if ($check->num_rows) {
            return;
        }

        // Find the matching OC product by SKU or listing_id
        $listing_id = (string)($reverb_order['listing']['id'] ?? '');
        $oc_product = $this->findProductByListingId($listing_id);

        if (!$oc_product) {
            $sku = $reverb_order['listing']['sku'] ?? '';
            $oc_product = $sku ? $this->findProductBySku($sku) : null;
        }

        if (!$oc_product) {
            // Create a placeholder product entry so the order can still be recorded
            $oc_product = [
                'product_id' => 0,
                'name'       => $reverb_order['listing']['title'] ?? 'Reverb Product',
                'model'      => $reverb_order['listing']['sku'] ?? '',
                'price'      => $reverb_order['total']['amount'] ?? 0,
            ];
        }

        require_once(DIR_SYSTEM . 'library/reverb/OrderMapper.php');

        $store_info = [
            'store_id'       => $this->config->get('config_store_id') ?? 0,
            'store_name'     => $this->config->get('config_name') ?? '',
            'store_url'      => $this->config->get('config_url') ?? '',
            'language_id'    => $this->config->get('config_language_id') ?? 1,
            'currency_id'    => 1,
            'currency_code'  => $this->config->get('config_currency') ?? 'AUD',
            'currency_value' => 1,
        ];

        $order_data = OrderMapper::toOpenCart($reverb_order, $oc_product, $store_info);

        $this->load->model('checkout/order');
        $order_id = $this->model_checkout_order->addOrder($order_data);

        // Decrease OC stock for the matched product
        if ($oc_product['product_id']) {
            $this->db->query("
                UPDATE `" . DB_PREFIX . "product`
                SET quantity = GREATEST(0, quantity - " . (int)($reverb_order['quantity'] ?? 1) . ")
                WHERE product_id = '" . (int)$oc_product['product_id'] . "'
            ");
        }

        $this->model_extension_module_reverb->log(
            $oc_product['product_id'],
            'pull',
            'success',
            'Created OC order #' . $order_id . ' from Reverb order #' . $order_number
        );
    }

    // -------------------------------------------------------------------------
    // Internal: cron helpers
    // -------------------------------------------------------------------------

    private function pollListingUpdates() {
        try {
            require_once(DIR_SYSTEM . 'library/reverb/ReverbApi.php');
            $token = $this->config->get('module_reverb_api_token');
            if (!$token) return;

            $api      = new ReverbApi($token);
            $response = $api->getListings();
            $listings = $response['listings'] ?? [];

            foreach ($listings as $listing) {
                $this->handleListingUpdate(['listing' => $listing]);
            }
        } catch (Exception $e) {
            $this->model_extension_module_reverb->log(0, 'pull', 'error', 'Poll listings failed: ' . $e->getMessage());
        }
    }

    private function pollOrders() {
        try {
            require_once(DIR_SYSTEM . 'library/reverb/ReverbApi.php');
            $token = $this->config->get('module_reverb_api_token');
            if (!$token) return;

            $api      = new ReverbApi($token);
            $response = $api->getOrders();
            $orders   = $response['orders'] ?? [];

            foreach ($orders as $order) {
                $this->handleOrderCreate(['order' => $order]);
            }
        } catch (Exception $e) {
            $this->model_extension_module_reverb->log(0, 'pull', 'error', 'Poll orders failed: ' . $e->getMessage());
        }
    }

    private function pushPendingProducts() {
        $this->load->model('setting/setting');
        $allowed_categories = $this->config->get('module_reverb_sync_categories') ?? [];
        if (empty($allowed_categories)) return;

        $settings = [
            'api_token'              => $this->config->get('module_reverb_api_token'),
            'shipping_domestic'      => $this->config->get('module_reverb_shipping_domestic') ?? '0',
            'shipping_international' => $this->config->get('module_reverb_shipping_international') ?? '0',
            'currency'               => $this->config->get('config_currency') ?? 'AUD',
            'store_url'              => $this->config->get('config_url') ?? '',
        ];

        $products = $this->model_extension_module_reverb->getSyncEnabledProducts((array)$allowed_categories);

        foreach ($products as $product) {
            try {
                $this->model_extension_module_reverb->syncProductToReverb($product, $product, $settings);
                $this->model_extension_module_reverb->log($product['product_id'], 'push', 'success', 'Cron sync: ' . $product['name']);
            } catch (Exception $e) {
                $this->model_extension_module_reverb->log($product['product_id'], 'push', 'error', $e->getMessage());
            }
        }
    }

    // -------------------------------------------------------------------------
    // DB lookups
    // -------------------------------------------------------------------------

    private function findProductByListingId($listing_id) {
        if (!$listing_id) return null;
        $query = $this->db->query("
            SELECT p.product_id, pd.name, p.model, p.price
            FROM `" . DB_PREFIX . "reverb_product_map` r
            JOIN `" . DB_PREFIX . "product` p ON p.product_id = r.product_id
            JOIN `" . DB_PREFIX . "product_description` pd ON pd.product_id = p.product_id
                AND pd.language_id = '" . (int)$this->config->get('config_language_id') . "'
            WHERE r.reverb_listing_id = '" . $this->db->escape($listing_id) . "'
            LIMIT 1
        ");
        return $query->num_rows ? $query->row : null;
    }

    private function findProductBySku($sku) {
        if (!$sku) return null;
        $query = $this->db->query("
            SELECT p.product_id, pd.name, p.model, p.price
            FROM `" . DB_PREFIX . "product` p
            JOIN `" . DB_PREFIX . "product_description` pd ON pd.product_id = p.product_id
                AND pd.language_id = '" . (int)$this->config->get('config_language_id') . "'
            WHERE p.model = '" . $this->db->escape($sku) . "'
            LIMIT 1
        ");
        return $query->num_rows ? $query->row : null;
    }
}