<?php

namespace App\Services\Import;

use App\Models\PosProduct;
use Illuminate\Support\Facades\DB;
use RuntimeException;

class MerchantCatalogImportService
{
    /**
     * @return array{imported: int, updated: int, storefronts: int}
     */
    public function import(string $ownerRef): array
    {
        if (! config('pos.merchant_import_enabled', true)) {
            throw new RuntimeException('Merchant catalog import is not configured.');
        }

        $connection = config('database.connections.merchant.database') ? 'merchant' : null;
        if ($connection === null || ! $this->connectionReady($connection)) {
            throw new RuntimeException('Merchant database connection is not available.');
        }

        $storefronts = DB::connection($connection)
            ->table('qr_codes')
            ->join('users', 'users.id', '=', 'qr_codes.user_id')
            ->where('users.public_id', $ownerRef)
            ->where('qr_codes.is_active', true)
            ->whereIn('qr_codes.type', ['shop', 'menu'])
            ->select('qr_codes.id', 'qr_codes.payload', 'qr_codes.label')
            ->get();

        if ($storefronts->isEmpty()) {
            throw new RuntimeException('No active Merchant storefronts found for this account.');
        }

        $imported = 0;
        $updated = 0;

        foreach ($storefronts as $storefront) {
            $payload = json_decode((string) $storefront->payload, true);
            $content = is_array($payload) ? (array) ($payload['content'] ?? []) : [];
            $sections = (array) ($content['sections'] ?? []);

            foreach ($sections as $section) {
                foreach ((array) ($section['items'] ?? []) as $item) {
                    $name = trim((string) ($item['name'] ?? ''));
                    $priceGhs = (float) ($item['price'] ?? 0);
                    if ($name === '' || $priceGhs <= 0) {
                        continue;
                    }

                    $priceMinor = (int) round($priceGhs * 100);
                    $sku = 'm'.$storefront->id.'-'.substr(md5($name), 0, 8);

                    $existing = PosProduct::owned($ownerRef)->where('sku', $sku)->first();
                    $attrs = [
                        'name' => $name,
                        'sku' => $sku,
                        'price_minor' => $priceMinor,
                        'currency' => config('pos.default_currency', 'GHS'),
                        'is_active' => true,
                    ];

                    if ($existing) {
                        $existing->update($attrs);
                        $updated++;
                    } else {
                        PosProduct::create([...$attrs, 'owner_ref' => $ownerRef]);
                        $imported++;
                    }
                }
            }
        }

        if ($imported === 0 && $updated === 0) {
            throw new RuntimeException('No catalog items found in Merchant storefronts.');
        }

        return [
            'imported' => $imported,
            'updated' => $updated,
            'storefronts' => $storefronts->count(),
        ];
    }

    private function connectionReady(string $connection): bool
    {
        try {
            DB::connection($connection)->getPdo();

            return true;
        } catch (\Throwable) {
            return false;
        }
    }
}