<?php

namespace App\Actions;

use App\Models\User;
use App\Models\WebhookEndpoint;
use Illuminate\Support\Facades\Gate;
use Illuminate\Support\Facades\Validator;
use Illuminate\Validation\ValidationException;

class ConfigureWebhookEndpointAction
{
    /**
     * @param  array<string, string|array<int, string>>  $headers
     */
    public function handle(
        ?User $user,
        WebhookEndpoint $endpoint,
        int $status,
        array $headers,
        string $body,
    ): WebhookEndpoint {
        Gate::forUser($user)->authorize('update', $endpoint);

        $maxResponseBodyBytes = (int) config('webhooks.max_response_body_bytes', 1024 * 1024);

        if (strlen($body) > $maxResponseBodyBytes) {
            throw ValidationException::withMessages([
                'response_body' => "The response body may not exceed {$maxResponseBodyBytes} bytes.",
            ]);
        }

        Validator::make([
            'status' => $status,
            'body' => $body,
        ], [
            'status' => ['integer', 'between:100,599'],
            'body' => ['string'],
        ])->validate();

        $this->validateHeaders($headers);

        $endpoint->forceFill([
            'response_status' => $status,
            'response_headers' => $headers,
            'response_body' => $body,
        ])->save();

        return $endpoint->refresh();
    }

    /**
     * @param  array<string, string|array<int, string>>  $headers
     */
    private function validateHeaders(array $headers): void
    {
        if (count($headers) > 50) {
            throw ValidationException::withMessages([
                'response_headers' => 'A maximum of 50 response headers is allowed.',
            ]);
        }

        foreach ($headers as $name => $value) {
            if (! is_string($name) || preg_match("/^[!#$%&'*+.^_`|~0-9A-Za-z-]+$/", $name) !== 1) {
                throw ValidationException::withMessages([
                    'response_headers' => 'Every response header name must be a valid HTTP header name.',
                ]);
            }

            $values = is_array($value) ? $value : [$value];

            foreach ($values as $headerValue) {
                if (! is_string($headerValue) || preg_match('/[\r\n]/', $headerValue) === 1 || strlen($headerValue) > 8192) {
                    throw ValidationException::withMessages([
                        'response_headers' => 'Response headers must not contain line breaks and may not exceed 8 KiB.',
                    ]);
                }
            }
        }
    }
}