<?php

declare(strict_types=1);

namespace Uwil\LaravelAdminSecure;

use Dxw\CIDR\IPv4Range;
use Dxw\CIDR\IPv6Range;
use Illuminate\Support\Facades\Cache;
use Symfony\Component\OptionsResolver\OptionsResolver;
use Uwil\LaravelAdminSecure\Exceptions\AdminSecureException;

/**
 * Configuration
 */
final class Options
{
    /** @var array<string, mixed> The configuration options. */
    private $options;

    /** @var \Symfony\Component\OptionsResolver\OptionsResolver The options resolver. */
    private $resolver;

    /** @var string The cache key where to store config cidr list. */
    private static string $cache_config_key = 'uwil_ip_cidr_config_list';

    /**
     * Class constructor.
     *
     * @param  array<string, mixed>  $options  The configuration options.
     */
    public function __construct(array $options = [])
    {
        $this->resolver = new OptionsResolver();

        $this->configureOptions($this->resolver);

        $this->options = $this->resolver->resolve($options);
    }

    /**
     * Get cidr list.
     *
     * @return array<\Dxw\CIDR\IPv4Range|\Dxw\CIDR\IPv6Range>
     */
    public function getCidrList(): array
    {
        return $this->options['cidrList'];
    }

    /**
     * Get cidr project allowed list.
     *
     * @return array<\Dxw\CIDR\IPv4Range|\Dxw\CIDR\IPv6Range>
     */
    public function getCidrAllowedList(): array
    {
        return $this->options['cidrProjectAllowedList'];
    }

    /**
     * Configures the options of the client.
     *
     * @param  \Symfony\Component\OptionsResolver\OptionsResolver  $resolver  The resolver for the options.
     */
    private function configureOptions(OptionsResolver $resolver): void
    {
        $resolver->setDefaults([
            'cidrList'               => [],
            'cidrProjectAllowedList' => [],
        ]);

        $resolver->setNormalizer('cidrList', $this->normalizeCidrList(...));
        $resolver->setNormalizer('cidrProjectAllowedList', $this->normalizeCidrProjectList(...));
    }

    /**
     * Normalise Cidr list for cidrList option.
     *
     * @return array<\Dxw\CIDR\IPv4Range|\Dxw\CIDR\IPv6Range>
     *
     * @phpcs:disable Generic.CodeAnalysis.UnusedFunctionParameter.FoundBeforeLastUsed
     */
    private function normalizeCidrList(
        \Symfony\Component\OptionsResolver\Options $options,
        ?string $value
    ): array {
        // phpcs:enable
        return $this->doNormalizeCidrList($value, 'cidrList');
    }

    /**
     * Normalise Cidr list for cidrProjectAllowedList option.
     *
     * @return array<\Dxw\CIDR\IPv4Range|\Dxw\CIDR\IPv6Range>
     *
     * @phpcs:disable Generic.CodeAnalysis.UnusedFunctionParameter.FoundBeforeLastUsed
     */
    private function normalizeCidrProjectList(
        \Symfony\Component\OptionsResolver\Options $options,
        ?string $value
    ): array {
        // phpcs:enable
        return $this->doNormalizeCidrList($value, 'cidrProjectAllowedList');
    }

    /**
     * Normalize CIDR list with specific cache key.
     *
     * @return array<\Dxw\CIDR\IPv4Range|\Dxw\CIDR\IPv6Range>
     */
    private function doNormalizeCidrList(?string $value, string $optionName): array
    {
        $cacheConfigKey                = self::$cache_config_key . '_' . $optionName;
        $allowed_cidr_config_list      = collect(explode(',', strval($value)))->filter();
        $allowed_cidr_config_list_hash = \md5($allowed_cidr_config_list->implode(','));

        /** @var array{list: array<\Dxw\CIDR\IPv4Range|\Dxw\CIDR\IPv6Range>, hash: string}|null $cached */
        $cached = Cache::get($cacheConfigKey);

        // Flush cache if config hash changed
        if ($cached === null || $cached['hash'] !== $allowed_cidr_config_list_hash) {
            Cache::forget($cacheConfigKey);

            /** @var array<\Dxw\CIDR\IPv4Range|\Dxw\CIDR\IPv6Range> $allowed_cidr_list */
            $allowed_cidr_list = $allowed_cidr_config_list
                ->map(function (string $cidr) {
                    $ip_range = ! IPv4Range::Make($cidr)->isErr() ? IPv4Range::Make($cidr) : IPv6Range::Make($cidr);
                    if ($ip_range->isErr()) {
                        throw new AdminSecureException(\trans(
                            'CIDR LIST not valid (ipv4 or ipv6 cidr) :cidr',
                            ['cidr' => $cidr]
                        ));
                    }

                    return $ip_range->unwrap();
                })->all();

            Cache::forever($cacheConfigKey, [
                'list' => $allowed_cidr_list,
                'hash' => $allowed_cidr_config_list_hash,
            ]);

            return $allowed_cidr_list;
        }

        return $cached['list'];
    }
}