<?php
/**
 * 后台模块：菜单注册、表单保存与资源加载。
 *
 * 五个页面：
 * - 翻译设置（顶级）：源语言、AI 服务配置、翻译指令
 * - 语言管理：目标语言的增删与每语言的替换规则
 * - 页面翻译：按页面查看/编辑原文与译文 JSON，可调 AI 翻译
 * - 译文数据：按记录浏览全库译文，可改可删
 * - 使用说明：翻译范围与「不要翻译」标记的说明（纯静态视图）
 *
 * @package Aipogeo_Context_Translate
 */

defined( 'ABSPATH' ) || exit;

/**
 * Class APGT_Admin
 */
class APGT_Admin {

	/** 翻译设置页 slug（同时是顶级菜单 slug）。 */
	const PAGE_SLUG = 'aipogeo-context-translate';

	/** 语言管理页 slug。 */
	const PAGE_LANGUAGES = 'apgt-languages';

	/** 页面翻译页 slug。 */
	const PAGE_TRANSLATE = 'apgt-pages';

	/** 译文数据页 slug。 */
	const PAGE_DATA = 'apgt-data';

	/** 使用说明页 slug。 */
	const PAGE_HELP = 'apgt-help';

	/** 翻译指令的最大长度（字符）。默认指令不到 2000 字，留足余量即可。 */
	const MAX_PROMPT_LENGTH = 20000;

	/** 单条替换规则里搜索串/替换串的最大长度（字符）。 */
	const MAX_RULE_LENGTH = 2000;

	/**
	 * 各页面的 hook suffix，供 admin_enqueue_scripts 精确匹配。
	 *
	 * 子菜单的 hook 由父菜单标题派生，中文标题下不可预测，所以记住注册时的返回值。
	 *
	 * @var array slug => hook suffix
	 */
	private $hooks = array();

	/**
	 * 注册后台钩子。
	 *
	 * @return void
	 */
	public function init() {
		add_action( 'admin_menu', array( $this, 'register_menu' ) );
		add_action( 'admin_enqueue_scripts', array( $this, 'enqueue_assets' ) );
		add_filter( 'plugin_action_links_' . APGT_PLUGIN_BASENAME, array( $this, 'add_action_links' ) );
		add_action( 'admin_init', array( $this, 'handle_connect_callback' ) );

		$ajax = new APGT_Ajax();
		$ajax->init();
	}

	/**
	 * 侧边栏菜单图标。
	 *
	 * 传 data URI 时 WordPress 把 SVG 当 background-image 用，颜色只能由 SVG 自己带，
	 * 所以文件里填的是后台默认图标灰，选中和悬停的提亮交给 menu_icon_style()。
	 *
	 * @return string data URI，图标文件缺失时退回 dashicon。
	 */
	private static function menu_icon() {
		$file = APGT_PLUGIN_DIR . 'assets/images/menu-icon.svg';
		if ( ! is_readable( $file ) ) {
			return 'dashicons-translation';
		}

		// 读的是插件自己目录下的静态文件，不涉及远程请求，用不着 WP_Filesystem。
		$svg = file_get_contents( $file ); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents

		return false === $svg || '' === $svg
			? 'dashicons-translation'
			: 'data:image/svg+xml;base64,' . base64_encode( $svg );
	}

	/**
	 * 菜单图标在选中和悬停时提亮。
	 *
	 * 背景图不像 dashicons 那样能被 WordPress 自动着色，只能自己补一条 filter。
	 * 菜单在所有后台页面都在，所以这段不能放进只在插件页加载的 admin.css；
	 * 挂成没有 src 的句柄再补内联样式，核心自己挂纯内联样式也是这个写法。
	 *
	 * @return void
	 */
	private function enqueue_menu_icon_style() {
		$selector = '#adminmenu #toplevel_page_' . self::PAGE_SLUG;
		$css      = sprintf(
			'%1$s:hover .wp-menu-image.svg,%1$s.current .wp-menu-image.svg,' .
			'%1$s.wp-has-current-submenu .wp-menu-image.svg{filter:brightness(1.8)}',
			$selector
		);

		wp_register_style( 'apgt-menu-icon', false, array(), APGT_VERSION );
		wp_enqueue_style( 'apgt-menu-icon' );
		wp_add_inline_style( 'apgt-menu-icon', $css );
	}

	/**
	 * 注册后台菜单。
	 *
	 * @return void
	 */
	public function register_menu() {
		$this->hooks[ self::PAGE_SLUG ] = add_menu_page(
			__( 'Aipogeo Context Translate', 'aipogeo-context-translate' ),
			__( 'Aipogeo Context Translate', 'aipogeo-context-translate' ),
			'manage_options',
			self::PAGE_SLUG,
			array( $this, 'render_settings' ),
			self::menu_icon(),
			76
		);

		add_submenu_page(
			self::PAGE_SLUG,
			__( 'Translation Settings', 'aipogeo-context-translate' ),
			__( 'Translation Settings', 'aipogeo-context-translate' ),
			'manage_options',
			self::PAGE_SLUG,
			array( $this, 'render_settings' )
		);

		$this->hooks[ self::PAGE_LANGUAGES ] = add_submenu_page(
			self::PAGE_SLUG,
			__( 'Languages', 'aipogeo-context-translate' ),
			__( 'Languages', 'aipogeo-context-translate' ),
			'manage_options',
			self::PAGE_LANGUAGES,
			array( $this, 'render_languages' )
		);

		$this->hooks[ self::PAGE_TRANSLATE ] = add_submenu_page(
			self::PAGE_SLUG,
			__( 'Translate Pages', 'aipogeo-context-translate' ),
			__( 'Translate Pages', 'aipogeo-context-translate' ),
			'manage_options',
			self::PAGE_TRANSLATE,
			array( $this, 'render_translate' )
		);

		$this->hooks[ self::PAGE_DATA ] = add_submenu_page(
			self::PAGE_SLUG,
			__( 'Translation Data', 'aipogeo-context-translate' ),
			__( 'Translation Data', 'aipogeo-context-translate' ),
			'manage_options',
			self::PAGE_DATA,
			array( $this, 'render_data' )
		);

		$this->hooks[ self::PAGE_HELP ] = add_submenu_page(
			self::PAGE_SLUG,
			__( 'Help', 'aipogeo-context-translate' ),
			__( 'Help', 'aipogeo-context-translate' ),
			'manage_options',
			self::PAGE_HELP,
			array( $this, 'render_help' )
		);

		// 表单保存要在页面输出之前跑（需要 redirect），挂在各页的 load 钩子上。
		add_action( 'load-' . $this->hooks[ self::PAGE_SLUG ], array( $this, 'handle_settings_save' ) );
		add_action( 'load-' . $this->hooks[ self::PAGE_LANGUAGES ], array( $this, 'handle_languages_save' ) );
	}

	/**
	 * 加载后台资源（仅本插件页面）。
	 *
	 * @param string $hook_suffix 当前后台页面标识。
	 * @return void
	 */
	public function enqueue_assets( $hook_suffix ) {
		// 菜单和 worker 在后台任意页面都在，所以先于「是不是插件页」判断。
		$this->enqueue_menu_icon_style();
		$this->enqueue_worker();

		$slug = array_search( $hook_suffix, $this->hooks, true );
		if ( false === $slug ) {
			return;
		}

		// 页面下拉有几百项、语言下拉有一百多项，都用 Choices 提供搜索过滤。
		$need_choices = in_array( $slug, array( self::PAGE_TRANSLATE, self::PAGE_SLUG, self::PAGE_LANGUAGES ), true );
		$choices      = APGT_PLUGIN_URL . 'assets/vendor/choices/';
		$style_deps   = array();
		if ( $need_choices ) {
			wp_enqueue_style( 'apgt-choices', $choices . 'choices.min.css', array(), '10.2.0' );
			$style_deps[] = 'apgt-choices';
		}

		// 插件样式排在 Choices 之后：改 Choices 外观的那些选择器不少与它自带的
		// 特异性相同（它给下拉写的是 .choices__list[aria-expanded]，也是两级），
		// 同分时谁后加载谁说了算，声明依赖才能稳定压住。
		wp_enqueue_style( 'apgt-admin', APGT_PLUGIN_URL . 'assets/css/admin.css', $style_deps, self::asset_version( 'assets/css/admin.css' ) );

		// 翻译设置页要编辑指令、页面翻译页要编辑 JSON，都用 Ace。
		$need_ace = in_array( $slug, array( self::PAGE_SLUG, self::PAGE_TRANSLATE ), true );
		if ( $need_ace ) {
			$ace = APGT_PLUGIN_URL . 'assets/vendor/ace/';
			wp_enqueue_script( 'apgt-ace', $ace . 'ace.js', array(), APGT_VERSION, true );
			wp_enqueue_script( 'apgt-ace-mode-json', $ace . 'mode-json.js', array( 'apgt-ace' ), APGT_VERSION, true );
			wp_enqueue_script( 'apgt-ace-mode-text', $ace . 'mode-text.js', array( 'apgt-ace' ), APGT_VERSION, true );
			wp_enqueue_script( 'apgt-ace-theme', $ace . 'theme-github.js', array( 'apgt-ace' ), APGT_VERSION, true );
			wp_enqueue_script( 'apgt-ace-searchbox', $ace . 'ext-searchbox.js', array( 'apgt-ace' ), APGT_VERSION, true );
		}

		$deps = array( 'jquery' );
		if ( $need_ace ) {
			$deps[] = 'apgt-ace';
		}

		if ( $need_choices ) {
			wp_enqueue_script( 'apgt-choices', $choices . 'choices.min.js', array(), '10.2.0', true );
			$deps[] = 'apgt-choices';
		}
		wp_enqueue_script( 'apgt-admin', APGT_PLUGIN_URL . 'assets/js/admin.js', $deps, self::asset_version( 'assets/js/admin.js' ), true );

		wp_localize_script(
			'apgt-admin',
			'apgtAdmin',
			array(
				'ajaxUrl'   => admin_url( 'admin-ajax.php' ),
				'nonce'     => wp_create_nonce( APGT_Ajax::NONCE ),
				'aceBase'   => APGT_PLUGIN_URL . 'assets/vendor/ace/',
				'page'      => $slug,
				'batchConcurrency' => max( 1, min( 5, (int) APGT_Settings::get_settings()['batch_concurrency'] ) ),
				// 模型名 / 协议标识 => 内置接口地址，设置页据此联动「接口地址」输入框。
				'models'    => self::PAGE_SLUG === $slug ? APGT_Translator::builtin_models() : array(),
				'protocols' => self::PAGE_SLUG === $slug ? APGT_Translator::protocol_endpoints() : array(),
				'i18n'      => array(
					'loading'      => __( 'Loading…', 'aipogeo-context-translate' ),
					'translating'  => __( 'Submitting to AI…', 'aipogeo-context-translate' ),
					/* translators: 1: number of AI requests completed, 2: seconds elapsed */
					'jobRunning'   => __( 'AI translation running in the background: %1$s AI requests completed, %2$s seconds elapsed', 'aipogeo-context-translate' ),
					'saving'       => __( 'Saving…', 'aipogeo-context-translate' ),
					'pickPage'     => __( 'Select a language and a page first', 'aipogeo-context-translate' ),
					'badJson'      => __( 'The translation JSON is malformed. Fix it before continuing.', 'aipogeo-context-translate' ),
					'requestFail'  => __( 'Request failed. Check the browser console or debug.log.', 'aipogeo-context-translate' ),
					/* translators: 1: total items, 2: translated items */
					'stats'        => __( '%1$s items, %2$s translated', 'aipogeo-context-translate' ),
					'searchPage'   => __( 'Filter by title or URL…', 'aipogeo-context-translate' ),
					'noResults'    => __( 'No matching pages', 'aipogeo-context-translate' ),
					'noChoices'    => __( 'No pages available', 'aipogeo-context-translate' ),
					'searchLang'   => __( 'Type a language name or code to filter…', 'aipogeo-context-translate' ),
					'noLangs'      => __( 'No matching languages', 'aipogeo-context-translate' ),
					'noLangChoice' => __( 'No languages available', 'aipogeo-context-translate' ),
					'confirmAll'   => __( 'This will translate every pending page, several at a time, starting with the language selected above and then moving on to the remaining target languages. It may use a large amount of AI credit. Start now?', 'aipogeo-context-translate' ),
					'batchPrep'    => __( 'Counting pending pages…', 'aipogeo-context-translate' ),
					/* translators: 1: pending pages, 2: translated pages, 3: total pages */
					'batchStat'    => __( '%1$s pending / %2$s translated (%3$s in total, all target languages)', 'aipogeo-context-translate' ),
					/* translators: 1: target language, 2: title of the page being translated */
					'batchDoing'   => __( '%1$s · Translating: %2$s', 'aipogeo-context-translate' ),
					/* translators: %1$s: target language */
					'batchSwitching' => __( 'Moving on to %1$s…', 'aipogeo-context-translate' ),
					/* translators: 1: pages succeeded, 2: pages failed */
					'batchDone'    => __( 'All done: %1$s pages succeeded, %2$s failed', 'aipogeo-context-translate' ),
					/* translators: 1: pages done, 2: pages failed, 3: pages left unprocessed */
					'batchStopped' => __( 'Stopped: %1$s pages done, %2$s failed, %3$s left unprocessed', 'aipogeo-context-translate' ),
					/* translators: %1$s: seconds until translation resumes */
					'batchThrottled' => __( 'The server asked us to slow down (rate limit). Resuming in %1$s seconds…', 'aipogeo-context-translate' ),
					'batchNothing' => __( 'No pending pages in any target language', 'aipogeo-context-translate' ),
					'stop'         => __( 'Stop', 'aipogeo-context-translate' ),
					'stopping'     => __( 'Stopping…', 'aipogeo-context-translate' ),
					'viewSource'   => __( 'Open the source page in a new window', 'aipogeo-context-translate' ),
					'viewTrans'    => __( 'Open the translated page in a new window', 'aipogeo-context-translate' ),
					'ruleLike'     => __( 'Word match', 'aipogeo-context-translate' ),
					'ruleExact'    => __( 'Exact match', 'aipogeo-context-translate' ),
					'ruleRegex'    => __( 'Regex replace', 'aipogeo-context-translate' ),
					'ruleDelete'   => __( 'Delete', 'aipogeo-context-translate' ),
					/* translators: %1$s: number of rules */
					'ruleCount'    => __( '%1$s rules', 'aipogeo-context-translate' ),
					'regexOk'      => __( 'Valid regex', 'aipogeo-context-translate' ),
					'regexBad'     => __( 'This regex does not compile. Please fix it.', 'aipogeo-context-translate' ),
					'regexChecking' => __( 'Checking regex…', 'aipogeo-context-translate' ),
					/* translators: %1$s: number of regex rules that do not compile */
					'regexInvalid' => __( '%1$s regex rules do not compile. Fix them before saving.', 'aipogeo-context-translate' ),
					/* translators: %1$s: list of missing variable names */
					'promptMissing' => __( "The translation prompt is missing required variables: %1\$s\n\nWithout them the AI never receives the languages or the source data, so the result is guaranteed to be wrong. Add them and save again.\n(Saving a completely empty prompt restores the default one.)", 'aipogeo-context-translate' ),
					'confirmPromptReset' => __( 'This replaces the editor content with the plugin\'s current default prompt and discards your edits. Continue?', 'aipogeo-context-translate' ),
					'dataSaving'   => __( 'Saving…', 'aipogeo-context-translate' ),
					'dataSaved'    => __( 'Saved', 'aipogeo-context-translate' ),
					'dataDeleting' => __( 'Deleting…', 'aipogeo-context-translate' ),
					'confirmDelRow' => __( 'Delete this translation record?', 'aipogeo-context-translate' ),
					/* translators: %1$s: number of translation records that match the current filter */
					'confirmDelAll' => __( "This permanently deletes all %1\$s translation records matching the current filter.\n\nContinue?", 'aipogeo-context-translate' ),
					'needFilter'   => __( 'Set at least one filter first, otherwise the entire table would be wiped', 'aipogeo-context-translate' ),
					'keyShow'      => __( 'Show', 'aipogeo-context-translate' ),
					'keyHide'      => __( 'Hide', 'aipogeo-context-translate' ),
					'aceMissing'   => __( 'The Ace editor failed to load. Check that assets/vendor/ace is complete.', 'aipogeo-context-translate' ),
					/* translators: separator between variable names in a list; Chinese uses the ideographic comma here */
					'listSep'      => _x( ', ', 'list separator', 'aipogeo-context-translate' ),
				),
			)
		);

		$this->enqueue_settings_script( $slug );
	}

	/**
	 * 翻译设置页专用脚本：订阅面板的激活 / 刷新 / 解绑。
	 *
	 * 订阅那块面板只有这一页有，脚本也就只在这一页加载；文案经 localize
	 * 送进去，页面本身不带任何内联脚本。
	 *
	 * @param string $slug 当前插件页 slug。
	 * @return void
	 */
	private function enqueue_settings_script( $slug ) {
		if ( self::PAGE_SLUG !== $slug ) {
			return;
		}

		// 切换器自定义 CSS 用核心自带的代码编辑器（CodeMirror + CSSLint）。
		// 用户在个人资料里关了语法高亮时返回 false，编辑框就是普通 textarea。
		$css_editor = wp_enqueue_code_editor( array( 'type' => 'text/css' ) );
		$deps       = array( 'apgt-admin' );
		if ( false !== $css_editor ) {
			$deps[] = 'code-editor';
		}

		wp_enqueue_script(
			'apgt-settings',
			APGT_PLUGIN_URL . 'assets/js/settings.js',
			$deps,
			self::asset_version( 'assets/js/settings.js' ),
			true
		);

		wp_localize_script(
			'apgt-settings',
			'apgtSettings',
			array(
				'cssEditor' => $css_editor,
				'i18n'      => array(
					'cssMarkup'      => __( 'HTML tags are not allowed in the switcher CSS. Remove every "<" character and save again.', 'aipogeo-context-translate' ),
					'confirmCssReset' => __( 'This replaces the editor content with the plugin\'s default switcher styles and discards your edits. Continue?', 'aipogeo-context-translate' ),
					'stateGrace'     => __( 'Grace period', 'aipogeo-context-translate' ),
					'stateActive'    => __( 'Active', 'aipogeo-context-translate' ),
					'stateUnusable'  => __( 'Unavailable', 'aipogeo-context-translate' ),
					'quotaUnlimited' => __( 'Unlimited', 'aipogeo-context-translate' ),
					'quotaUnit'      => __( 'tokens', 'aipogeo-context-translate' ),
					'boundYes'       => __( 'Activated', 'aipogeo-context-translate' ),
					'boundNo'        => __( 'Not activated', 'aipogeo-context-translate' ),
					'working'        => __( 'Working…', 'aipogeo-context-translate' ),
					'failed'         => __( 'That did not work', 'aipogeo-context-translate' ),
					'done'           => __( 'Done', 'aipogeo-context-translate' ),
					'requestFail'    => __( 'The request failed. Please try again shortly.', 'aipogeo-context-translate' ),
					'confirmRelease' => __( 'Releasing this site stops it translating through this subscription. Continue?', 'aipogeo-context-translate' ),
				),
			)
		);
	}

	/**
	 * 自有资源的缓存版本号：取文件修改时间。
	 *
	 * 只用插件版本号做 ver 的话，开发期改了 JS 而版本没动，浏览器会一直
	 * 用缓存的旧脚本，新接口配旧脚本什么怪相都可能出现。vendor 资源不动，
	 * 仍按库版本号标。
	 *
	 * @param string $rel 相对插件根目录的路径。
	 * @return string
	 */
	private static function asset_version( $rel ) {
		$mtime = filemtime( APGT_PLUGIN_DIR . $rel );
		return $mtime ? (string) $mtime : APGT_VERSION;
	}

	/**
	 * 后台自动翻译 worker：登录后台的管理员浏览器定时来领任务。
	 *
	 * 挂在所有后台页面上，只要开关开着就跑；服务端有锁，多人同时开着后台
	 * 也只有一个进程真正在翻译。
	 *
	 * @return void
	 */
	private function enqueue_worker() {
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}

		// 只在「管理员在后台时」这种方式下由浏览器驱动；计划任务方式由 WP-Cron 自己跑。
		if ( APGT_Cron::MODE_BROWSER !== APGT_Cron::mode() ) {
			return;
		}
		$settings = APGT_Settings::get_settings();

		wp_enqueue_script(
			'apgt-worker',
			APGT_PLUGIN_URL . 'assets/js/worker.js',
			array( 'jquery' ),
			self::asset_version( 'assets/js/worker.js' ),
			true
		);

		wp_localize_script(
			'apgt-worker',
			'apgtWorker',
			array(
				'ajaxUrl'  => admin_url( 'admin-ajax.php' ),
				'nonce'    => wp_create_nonce( APGT_Ajax::NONCE ),
				'interval' => max( 15, (int) $settings['worker_interval'] ),
			)
		);
	}

	/**
	 * 保存「翻译设置」表单。
	 *
	 * @return void
	 */
	/**
	 * 处理订阅服务的连接回调。
	 *
	 * 用户在服务站点点了「授权」后会被送回设置页，地址里带一次性 code。
	 * 这里把 code 换成密钥存好，再把 code 从地址栏抹掉重定向一次 ——
	 * 免得用户刷新页面时拿着已作废的 code 再换一遍、看到一条莫名的报错。
	 *
	 * @return void
	 */
	public function handle_connect_callback() {
		// phpcs:ignore WordPress.Security.NonceVerification.Recommended -- 校验用 state，见 handle_callback()
		if ( ! isset( $_GET['code'] ) || ! isset( $_GET['page'] ) ) {
			return;
		}
		// phpcs:ignore WordPress.Security.NonceVerification.Recommended
		if ( self::PAGE_SLUG !== sanitize_key( wp_unslash( $_GET['page'] ) ) ) {
			return;
		}
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}

		$res = APGT_Service::handle_callback();
		if ( null === $res ) {
			return;
		}

		set_transient( 'apgt_connect_notice', $res, 60 );
		wp_safe_redirect( remove_query_arg( array( 'code', 'state' ) ) );
		exit;
	}

	public function handle_settings_save() {
		if ( ! isset( $_POST['apgt_save_settings'] ) ) {
			return;
		}
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_die( esc_html__( 'Insufficient permissions', 'aipogeo-context-translate' ) );
		}
		check_admin_referer( 'apgt_settings' );

		$settings                     = APGT_Settings::get_settings();
		$settings['default_language'] = isset( $_POST['default_language'] )
			? sanitize_text_field( wp_unslash( $_POST['default_language'] ) )
			: '';
		$settings['is_trans_url']     = empty( $_POST['is_trans_url'] ) ? 0 : 1;
		$auto_worker                  = isset( $_POST['auto_worker'] ) ? (int) $_POST['auto_worker'] : 0;
		$settings['auto_worker']      = in_array( $auto_worker, array( APGT_Cron::MODE_BROWSER, APGT_Cron::MODE_CRON ), true ) ? $auto_worker : APGT_Cron::MODE_OFF;
		$settings['worker_interval']  = isset( $_POST['worker_interval'] )
			? max( 15, (int) $_POST['worker_interval'] )
			: 60;
		$settings['batch_concurrency'] = isset( $_POST['batch_concurrency'] )
			? max( 1, min( 5, (int) $_POST['batch_concurrency'] ) )
			: 2;
		$settings['realtime_trans']   = empty( $_POST['realtime_trans'] ) ? 0 : 1;
		$settings['realtime_ratio']   = isset( $_POST['realtime_ratio'] )
			? max( 0, min( 100, (int) $_POST['realtime_ratio'] ) )
			: 100;
		$settings['show_hreflang']    = empty( $_POST['show_hreflang'] ) ? 0 : 1;
		$settings['show_switcher']    = empty( $_POST['show_switcher'] ) ? 0 : 1;
		$settings['show_flag']        = empty( $_POST['show_flag'] ) ? 0 : 1;
		$settings['menu_container']   = isset( $_POST['menu_container'] )
			// 只留 id 里合法的字符，用户可能连 # 一起粘进来。
			? preg_replace( '/[^A-Za-z0-9_\-:.]/', '', sanitize_text_field( wp_unslash( $_POST['menu_container'] ) ) )
			: '';

		if ( isset( $_POST['switcher_style'] ) ) {
			$style                      = sanitize_key( wp_unslash( $_POST['switcher_style'] ) );
			$settings['switcher_style'] = in_array( $style, APGT_Settings::SWITCHER_STYLES, true ) ? $style : 'default';
		}

		// 抓取用 IP：填错了不能就这么存进去——写死一个连不通的地址，
		// 比不填还糟，页面从此一个也抓不到。存空并回一条提示。
		$fetch_ip             = isset( $_POST['fetch_ip'] )
			? trim( sanitize_text_field( wp_unslash( $_POST['fetch_ip'] ) ) )
			: '';
		$bad_ip               = '' !== $fetch_ip && ! rest_is_ip_address( $fetch_ip );
		$settings['fetch_ip'] = $bad_ip ? '' : $fetch_ip;

		APGT_Settings::save_settings( $settings );
		// 开关计划任务不必等下一个请求。
		APGT_Cron::sync();

		$ai = APGT_Settings::get_ai();
		foreach ( array( 'model', 'api_key', 'proxy' ) as $key ) {
			if ( isset( $_POST[ $key ] ) ) {
				$ai[ $key ] = sanitize_text_field( wp_unslash( $_POST[ $key ] ) );
			}
		}
		if ( isset( $_POST['provider'] ) ) {
			$provider       = sanitize_key( wp_unslash( $_POST['provider'] ) );
			$ai['provider'] = in_array( $provider, array( 'core', 'plugin', 'service' ), true ) ? $provider : '';
		}
		// 订阅服务：密钥按原样存（它是随机串，任何"清理"都可能改坏字符）；
		// 服务地址去掉尾斜杠，免得后面拼接出双斜杠。
		if ( isset( $_POST['license_key'] ) ) {
			$ai['license_key'] = sanitize_text_field( wp_unslash( $_POST['license_key'] ) );
		}
		if ( isset( $_POST['service_url'] ) ) {
			// 先 esc_url_raw 再收拾尾巴：清理必须紧跟着 unslash，中间夹别的调用
			// 静态检查会认成「未清理就用了」。
			$service_url       = esc_url_raw( wp_unslash( $_POST['service_url'] ) );
			$ai['service_url'] = untrailingslashit( trim( $service_url ) );
		}
		if ( isset( $_POST['protocol'] ) ) {
			// 只认库里有的协议标识，留空表示由模型名自动识别。
			$protocol       = sanitize_key( wp_unslash( $_POST['protocol'] ) );
			$ai['protocol'] = array_key_exists( $protocol, APGT_Translator::protocols() ) ? $protocol : '';
		}
		if ( isset( $_POST['api_url'] ) ) {
			// trim() 必须在 sanitize_url() 之前：后者只 ltrim，尾部空格会被转成 %20，
			// 用户从文档里连空格一起粘贴时，接口地址就废了。
			// phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- 去空格后紧接着 sanitize_url()。
			$api_url = sanitize_url( trim( wp_unslash( $_POST['api_url'] ) ) );
			// 填的就是默认地址时存空，这样以后库里换了地址能自动跟上。
			$ai['api_url'] = $api_url === APGT_Translator::default_endpoint( $ai ) ? '' : $api_url;
		}
		foreach ( array( 'max_tokens', 'timeout' ) as $key ) {
			if ( isset( $_POST[ $key ] ) ) {
				$ai[ $key ] = max( 0, (int) $_POST[ $key ] );
			}
		}
		APGT_Settings::save_ai( $ai );

		$args = array(
			'page'    => self::PAGE_SLUG,
			'updated' => 1,
		);
		if ( $bad_ip ) {
			$args['bad_ip'] = 1;
		}

		// 切换器自定义样式：只存数据库、只经 wp_add_inline_style() 输出，不写任何文件。
		// 不能走 sanitize_textarea_field()，它会把 CSS 里的 > 选择器之类削掉；
		// 这里只统一换行、去掉控制字符，能不能用由 switcher_css_error() 把关。
		if ( isset( $_POST['switcher_css'] ) ) {
			// phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- 下一行即为清理。
			$css   = apgt_sanitize_css( wp_unslash( $_POST['switcher_css'] ) );
			// 与默认样式一字不差就不存：编辑框本来就预填默认样式，没改过的
			// 用户不该因此被记成「有自定义样式」，默认样式以后更新也跟得上。
			if ( trim( APGT_Settings::default_switcher_css() ) === $css ) {
				$css = '';
			}
			$error = APGT_Settings::switcher_css_error( $css );
			if ( '' === $error ) {
				APGT_Settings::save_switcher_css( $css );
			} else {
				// 其余设置照常保存，只把这段样式挡下。
				unset( $args['updated'] );
				$args['notice'] = 'css_' . $error;
			}
		}

		if ( isset( $_POST['prompt'] ) ) {
			// 指令是多行自由文本，里面既有 JSON 示例也可能提到 HTML 标签，
			// 交给 sanitize_textarea_field() 会被 strip_tags 削掉一截，
			// 所以走本插件按这类内容收紧的清理，见 apgt_sanitize_translatable_text()。
			// phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- 下一行即为清理。
			$prompt = apgt_sanitize_translatable_text( wp_unslash( $_POST['prompt'] ), self::MAX_PROMPT_LENGTH );

			if ( '' === $prompt ) {
				// 空指令等于没法翻译，回落到默认，别把插件置于不可用状态。
				APGT_Settings::save_prompt( APGT_Settings::default_prompt() );
				$args['notice'] = 'prompt_reset';
			} else {
				$missing = APGT_Prompt::missing_vars( $prompt );
				if ( $missing ) {
					// 少了变量，AI 收到的指令里就没有语言或待译数据，翻译必然是错的。
					// 其余设置照常保存，只把指令挡下。
					unset( $args['updated'] );
					$args['notice']  = 'prompt_missing';
					$args['missing'] = implode( ',', $missing );
				} else {
					APGT_Settings::save_prompt( $prompt );
				}
			}
		}

		if ( isset( $_POST['url_prompt'] ) ) {
			// 同上，见 $_POST['prompt'] 处的说明。
			// phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized -- 下一行即为清理。
			$url_prompt = apgt_sanitize_translatable_text( wp_unslash( $_POST['url_prompt'] ), self::MAX_PROMPT_LENGTH );

			if ( '' === $url_prompt ) {
				APGT_Settings::save_url_prompt( APGT_Settings::default_url_prompt() );
				$args['notice'] = 'url_prompt_reset';
			} else {
				$missing = APGT_Prompt::missing_vars( $url_prompt );
				if ( $missing ) {
					unset( $args['updated'] );
					$args['notice']  = 'url_prompt_missing';
					$args['missing'] = implode( ',', $missing );
				} else {
					APGT_Settings::save_url_prompt( $url_prompt );
				}
			}
		}

		wp_safe_redirect( add_query_arg( $args, admin_url( 'admin.php' ) ) );
		exit;
	}

	/**
	 * 保存「语言管理」表单（添加/删除/更新目标语言）。
	 *
	 * @return void
	 */
	public function handle_languages_save() {
		if ( ! isset( $_POST['apgt_languages_action'] ) ) {
			return;
		}
		if ( ! current_user_can( 'manage_options' ) ) {
			wp_die( esc_html__( 'Insufficient permissions', 'aipogeo-context-translate' ) );
		}
		check_admin_referer( 'apgt_languages' );

		$action   = sanitize_text_field( wp_unslash( $_POST['apgt_languages_action'] ) );
		$settings = APGT_Settings::get_settings();
		$langs    = is_array( $settings['languages'] ) ? $settings['languages'] : array();
		$meta     = APGT_Settings::language_meta();
		$notice   = 'saved';

		if ( 'add' === $action ) {
			$iso = isset( $_POST['new_language'] ) ? sanitize_text_field( wp_unslash( $_POST['new_language'] ) ) : '';
			if ( '' === $iso || ! isset( $meta[ $iso ] ) ) {
				$notice = 'bad_language';
			} elseif ( isset( $langs[ $iso ] ) ) {
				$notice = 'exists';
			} elseif ( $iso === $settings['default_language'] ) {
				$notice = 'same_as_source';
			} else {
				$row           = APGT_Settings::default_language_row( $iso );
				$row['sort']   = count( $langs ) + 1;
				$langs[ $iso ] = $row;
				$notice        = 'added';
			}
		} elseif ( 'delete' === $action ) {
			$iso = isset( $_POST['iso'] ) ? sanitize_text_field( wp_unslash( $_POST['iso'] ) ) : '';
			if ( isset( $langs[ $iso ] ) ) {
				unset( $langs[ $iso ] );
				$notice = 'deleted';
			}
		} elseif ( 'update' === $action ) {
			// phpcs:ignore WordPress.Security.ValidatedSanitizedInput -- 逐字段单独 sanitize。
			$rows = isset( $_POST['lang'] ) && is_array( $_POST['lang'] ) ? wp_unslash( $_POST['lang'] ) : array();
			foreach ( $rows as $iso => $row ) {
				$iso = sanitize_text_field( $iso );
				if ( ! isset( $langs[ $iso ] ) ) {
					continue;
				}
				$langs[ $iso ]['dir']           = isset( $row['dir'] ) ? sanitize_title( $row['dir'] ) : $iso;
				$langs[ $iso ]['hreflang_name'] = isset( $row['hreflang_name'] ) ? sanitize_text_field( $row['hreflang_name'] ) : $iso;
				$langs[ $iso ]['hreflang_area'] = isset( $row['hreflang_area'] ) ? sanitize_text_field( $row['hreflang_area'] ) : '';
				$langs[ $iso ]['sort']          = isset( $row['sort'] ) ? (int) $row['sort'] : 0;
				$langs[ $iso ]['mode']          = isset( $row['mode'] ) && in_array( $row['mode'], array( '0', '1', '2' ), true )
					? $row['mode']
					: '0';

				if ( '' === $langs[ $iso ]['dir'] ) {
					$langs[ $iso ]['dir'] = $iso;
				}

				// 替换规则由弹窗编辑后以 JSON 提交，解析或正则校验失败就保留原值并提示。
				if ( isset( $row['text_replace'] ) ) {
					$rule_error = '';
					$parsed     = self::parse_text_replace( $row['text_replace'], $rule_error );
					if ( '' !== $rule_error ) {
						$notice = $rule_error;
					} else {
						$langs[ $iso ]['text_replace'] = $parsed;
					}
				}
			}
		}

		$settings['languages'] = $langs;
		APGT_Settings::save_settings( $settings );

		wp_safe_redirect(
			add_query_arg(
				array(
					'page'   => self::PAGE_LANGUAGES,
					'notice' => $notice,
				),
				admin_url( 'admin.php' )
			)
		);
		exit;
	}

	/**
	 * 判断一段字符串能不能当正则用。
	 *
	 * 与 website-dev 的 /apis/strings/validate_regex 同一判据：拿空串试跑一次，
	 * 编译失败时 preg_match 返回 false。
	 *
	 * @param string $pattern 正则（需自带分隔符）。
	 * @return bool
	 */
	public static function is_valid_regex( $pattern ) {
		$pattern = (string) $pattern;
		if ( '' === trim( $pattern ) ) {
			return false;
		}
		return false !== @preg_match( $pattern, '' ); // phpcs:ignore WordPress.PHP.NoSilencedErrors
	}

	/**
	 * 解析替换规则 JSON。
	 *
	 * @param string $json  规则 JSON（数组，每项含 type/search/replace）。
	 * @param string $error 出参：'bad_json' / 'bad_regex'，无误时为空串。
	 * @return array 解析出的规则；出错时返回空数组，调用方应保留原值。
	 */
	private static function parse_text_replace( $json, &$error = '' ) {
		$error = '';
		$json  = trim( (string) $json );
		if ( '' === $json ) {
			return array();
		}

		$data = json_decode( $json, true );
		if ( ! is_array( $data ) ) {
			$error = 'bad_json';
			return array();
		}

		$out = array();
		foreach ( $data as $item ) {
			if ( ! is_array( $item ) || ! isset( $item['search'] ) || '' === (string) $item['search'] ) {
				continue;
			}
			$type   = isset( $item['type'] ) ? sanitize_key( (string) $item['type'] ) : 'like_replace';
			$type   = in_array( $type, array( 'replace', 'like_replace', 'preg_replace' ), true ) ? $type : 'like_replace';
			// 规则要逐字匹配译文，同样不能过标签过滤器，理由见 apgt_sanitize_translatable_text()。
			$search = apgt_sanitize_translatable_text( $item['search'], self::MAX_RULE_LENGTH );
			if ( '' === $search ) {
				continue;
			}

			// 正则写错时 preg_replace 会静默失败，这条规则就永远不起作用了，
			// 不如在保存这一步就拦住。
			if ( 'preg_replace' === $type && ! self::is_valid_regex( $search ) ) {
				$error = 'bad_regex';
				return array();
			}

			$out[] = array(
				'type'    => $type,
				'search'  => $search,
				'replace' => isset( $item['replace'] )
					? apgt_sanitize_translatable_text( $item['replace'], self::MAX_RULE_LENGTH )
					: '',
			);
		}
		return $out;
	}

	/**
	 * 在插件列表页添加「设置」链接。
	 *
	 * @param array $links 原有链接。
	 * @return array
	 */
	public function add_action_links( $links ) {
		$settings_link = sprintf(
			'<a href="%s">%s</a>',
			esc_url( admin_url( 'admin.php?page=' . self::PAGE_SLUG ) ),
			esc_html__( 'Settings', 'aipogeo-context-translate' )
		);

		array_unshift( $links, $settings_link );

		return $links;
	}

	/**
	 * 渲染翻译设置页。
	 *
	 * @return void
	 */
	public function render_settings() {
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}
		require APGT_PLUGIN_DIR . 'admin/views/settings-page.php';
	}

	/**
	 * 渲染语言管理页。
	 *
	 * @return void
	 */
	public function render_languages() {
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}
		require APGT_PLUGIN_DIR . 'admin/views/languages-page.php';
	}

	/**
	 * 渲染页面翻译页。
	 *
	 * @return void
	 */
	public function render_translate() {
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}
		require APGT_PLUGIN_DIR . 'admin/views/translate-page.php';
	}

	/**
	 * 渲染译文数据页。
	 *
	 * @return void
	 */
	public function render_data() {
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}
		require APGT_PLUGIN_DIR . 'admin/views/data-page.php';
	}

	/**
	 * 渲染使用说明页。
	 *
	 * @return void
	 */
	public function render_help() {
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}
		require APGT_PLUGIN_DIR . 'admin/views/help-page.php';
	}

	/**
	 * 输出插件各页面的顶部导航（当前页高亮）。
	 *
	 * @param string $current 当前页 slug。
	 * @return void
	 */
	public static function render_nav( $current ) {
		$tabs = array(
			self::PAGE_SLUG      => __( 'Translation Settings', 'aipogeo-context-translate' ),
			self::PAGE_LANGUAGES => __( 'Languages', 'aipogeo-context-translate' ),
			self::PAGE_TRANSLATE => __( 'Translate Pages', 'aipogeo-context-translate' ),
			self::PAGE_DATA      => __( 'Translation Data', 'aipogeo-context-translate' ),
			self::PAGE_HELP      => __( 'Help', 'aipogeo-context-translate' ),
		);
		echo '<nav class="nav-tab-wrapper apgt-nav">';
		foreach ( $tabs as $slug => $label ) {
			printf(
				'<a href="%s" class="nav-tab%s">%s</a>',
				esc_url( admin_url( 'admin.php?page=' . $slug ) ),
				$slug === $current ? ' nav-tab-active' : '',
				esc_html( $label )
			);
		}
		echo '</nav>';
	}
}