<?php

namespace App\Services;

use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Storage;

class DisplayQrCodeService
{
    /**
     * @return array{path: string, url: string}|null
     */
    public function generateForUrl(?string $url): ?array
    {
        $normalizedUrl = $this->normalizeUrl($url);

        if ($normalizedUrl === '') {
            return null;
        }

        $path = 'display-qr-codes/'.sha1($normalizedUrl).'.png';
        $disk = Storage::disk('public');

        if (! $disk->exists($path)) {
            try {
                $response = Http::timeout(10)
                    ->retry(2, 300)
                    ->get($this->remoteQrUrl($normalizedUrl));

                if (! $response->successful() || $response->body() === '') {
                    return null;
                }

                $disk->put($path, $response->body());
            } catch (\Throwable) {
                return null;
            }
        }

        return [
            'path' => $path,
            'url' => asset('storage/'.$path),
        ];
    }

    public function normalizeUrl(?string $url): string
    {
        $url = trim((string) $url);

        if ($url === '') {
            return '';
        }

        if (str_starts_with($url, 'http://') || str_starts_with($url, 'https://')) {
            return $url;
        }

        return 'https://'.$url;
    }

    private function remoteQrUrl(string $url): string
    {
        return 'https://api.qrserver.com/v1/create-qr-code/?'.http_build_query([
            'size' => '300x300',
            'margin' => '8',
            'color' => '000000',
            'bgcolor' => 'ffffff',
            'data' => $url,
        ]);
    }
}