<?php

declare(strict_types=1);

namespace app\common\middleware;

use Webman\MiddlewareInterface;
use Webman\Http\Request;
use Webman\Http\Response;

/**
 * 加载控制器语言包中间件（Webman 迁移版，等价 ThinkPHP LoadLangPack）
 * 根据当前路由加载对应控制器的语言包到 Translator
 */
class LoadLangPack implements MiddlewareInterface
{
    public function process(Request $request, callable $handler): Response
    {
        $path = trim($request->path(), '/');
        if (str_starts_with($path, 'api/') || str_starts_with($path, 'admin/')) {
            $this->loadLang($request);
        }
        return $handler($request);
    }

    protected function loadLang(Request $request): void
    {
        // 优先从请求头 think-lang 获取前端选择的语言（与前端 axios 发送的 header 对应）
        $headerLang = $request->header('think-lang');
        $allowLangList = config('lang.allow_lang_list', ['zh-cn', 'en']);
        if ($headerLang && in_array(str_replace('_', '-', strtolower($headerLang)), $allowLangList)) {
            $langSet = str_replace('_', '-', strtolower($headerLang));
        } else {
            $langSet = config('lang.default_lang', config('translation.locale', 'zh-cn'));
            $langSet = str_replace('_', '-', strtolower($langSet));
        }

        // 设置当前请求的翻译语言，使 __() 和 trans() 使用正确的语言
        if (function_exists('locale')) {
            locale($langSet);
        }

        $path = trim($request->path(), '/');
        $parts = explode('/', $path);
        $app = $parts[0] ?? 'api';

        $appLangDir = base_path() . DIRECTORY_SEPARATOR . 'app' . DIRECTORY_SEPARATOR . $app . DIRECTORY_SEPARATOR . 'lang' . DIRECTORY_SEPARATOR;

        if (!class_exists(\support\Translation::class)) {
            return;
        }

        $translator = \support\Translation::instance();

        // 1. 加载根级语言包（zh-cn.php / en.php），供 common 翻译使用
        $rootLangFile = $appLangDir . $langSet . '.php';
        if (is_file($rootLangFile)) {
            $translator->addResource('phpfile', $rootLangFile, $langSet, 'messages');
        }

        // 2. 加载控制器专用语言包（如 zh-cn/auth/group.php），供 get_route_remark 等使用
        $controllerPath = get_controller_path($request);
        if ($controllerPath) {
            $controllerPathForFile = str_replace('.', '/', $controllerPath);
            $controllerPathForFile = implode('/', array_map(function ($p) {
                return strtolower(preg_replace('/([a-z])([A-Z])/', '$1_$2', $p));
            }, explode('/', $controllerPathForFile)));
            $controllerLangFile = $appLangDir . $langSet . DIRECTORY_SEPARATOR . str_replace('/', DIRECTORY_SEPARATOR, $controllerPathForFile) . '.php';
            if (is_file($controllerLangFile)) {
                $translator->addResource('phpfile', $controllerLangFile, $langSet, $controllerPath);
            }
        }
    }
}