<?php

declare(strict_types=1);

namespace App\Http\Middleware;

use App\Lib\Helpers\ToolboxHelper;
use Illuminate\Http\Request;
use Illuminate\Http\UploadedFile;
use Mews\Purifier\Purifier;
use Symfony\Component\HttpFoundation\Response;

class HtmlSanitizer
{
    public function __construct(
        private readonly Purifier $purifierService
    ) {
    }

    /**
     * Handle an incoming request.
     *
     * @param  \Closure(\Illuminate\Http\Request):(\Illuminate\Http\Response)  $next
     * @param  string  ...$params  List of input names that should be sanitized with rich sanitization (allowing some HTML)
     */
    public function handle(Request $request, \Closure $next, string ...$params): Response
    {
        $inputs = $request->all();

        \array_walk($inputs, function (null | string | array | UploadedFile &$input, string $name) use ($params): void {
            $this->cleanInput($input, $name, null, $params);
        });
        $request->merge($inputs);

        return $next($request);
    }

    /**
     * @param  null|string|array<string,mixed>|\Illuminate\Http\UploadedFile  $input
     * @param  string[]  $params
     */
    private function cleanInput(
        null | string | array | UploadedFile &$input,
        string $name,
        ?string $rootName,
        array $params
    ): void {
        if (is_array($input)) {
            array_walk_recursive(
                $input,
                function (null | string | array | UploadedFile &$nestedInput, string $nestedName) use ($name, $params): void {
                    $this->cleanInput($nestedInput, $nestedName, $name, $params);
                }
            );
        }

        if (! is_string($input)) {
            return;
        }

        if ($this->shouldApplyRichSanitization($name, $rootName, $params)) {
            $this->sanitizeRichInput($input);

            return;
        }

        $input = strip_tags($input);
    }

    /**
     * @param  array<int,string|string[]>  $params
     */
    private function shouldApplyRichSanitization(string $name, ?string $rootName, array $params): bool
    {
        return in_array($name, $params) || in_array($rootName ?? $name, $params);
    }

    private function sanitizeRichInput(string &$input): void
    {
        $isJson = \json_decode($input, true);
        if ($isJson && is_array($isJson)) {
            \array_walk_recursive($isJson, function (string | array &$item): void {
                if (\is_string($item)) {
                    $item = $this->purifyString($item);
                }
            });

            $input = json_encode($isJson, \JSON_THROW_ON_ERROR) ?: throw new \UnexpectedValueException('Failed to encode JSON after sanitization.');

            return;
        }

        $input = $this->purifyString($input);
    }

    private function purifyString(string $input): string
    {
        $cleaned = $this->purifierService->clean($input);

        if (! is_string($cleaned)) {
            throw new \UnexpectedValueException('Purifier should return a string when input is a string.');
        }

        return ToolboxHelper::stripCkEditorSchemesOnMediaInputs($cleaned);
    }
}