Changeset 3456920

Timestamp:

02/09/2026 10:07:53 AM (12 days ago)

Author:

gkanters

Message:

Update trunk for version 2.2.6

Location:

ai-translate/trunk

Files:

• README.md (modified) (3 diffs)
• ai-translate.php (modified) (19 diffs)
• includes/admin-page.php (modified) (6 diffs)
• includes/class-ai-cache-meta.php (modified) (4 diffs)
• includes/class-ai-cache.php (modified) (1 diff)
• includes/class-ai-ob.php (modified) (4 diffs)
• includes/class-ai-seo.php (modified) (1 diff)

ai-translate/trunk/README.md

@@ -4 +4 @@
 Requires at least: 5.0  
 Tested up to: 6.9  
-Stable tag: 2.2.5
+Stable tag: 2.2.6
 Requires PHP: 8.0
 License: GPLv2 or later  
@@ -185 +185 @@
 ## Changelog
 
-### 2.2.5
+### 2.2.6
 - Improve system prompt (role, what and how).
 - Improve website context generator (what is the website about).
@@ -191 +191 @@
 - All enabled and detectable languages added to Wordpress sitemap (/wp-sitemap.xml) 
 - Code base refactoring. Improve performance and security, thighening code.
+
 
 ### 2.2.4

ai-translate/trunk/ai-translate.php

@@ -6 +6 @@
  * Author: NetCare
  * Author URI: https://netcare.nl/
- * Version: 2.2.5
+ * Version: 2.2.6
  * Requires at least: 5.0
  * Tested up to: 6.9
@@ -729 +729 @@
     }
 
+    // RULE 0: Strip explicit ?lang= query parameter from URL → redirect to clean path-based URL
+    // The ?lang= parameter is only used internally by rewrite rules, never in actual visitor URLs.
+    // Examples: /es?lang=fr → /es/  |  /?lang=es → /es/  |  /?lang={default} → /
+    if (isset($_GET['lang']) && trim((string) $_GET['lang']) !== '') {
+        $cleanParams = $_GET;
+        unset($cleanParams['lang']);
+
+        $targetPath = $reqPath;
+        if ($langFromUrl === null) {
+            // No language in path yet — use the GET parameter to build the correct path
+            $getLang = strtolower(sanitize_key((string) $_GET['lang']));
+            if ($getLang !== '' && $defaultLang && strtolower($getLang) !== strtolower((string) $defaultLang)) {
+                $targetPath = '/' . $getLang . '/';
+            }
+        }
+
+        // Ensure trailing slash (except bare root)
+        if ($targetPath !== '/' && substr($targetPath, -1) !== '/') {
+            $targetPath .= '/';
+        }
+
+        $targetUrl = home_url($targetPath);
+        if (!empty($cleanParams)) {
+            $targetUrl = add_query_arg($cleanParams, $targetUrl);
+        }
+
+        nocache_headers();
+        wp_safe_redirect(esc_url_raw($targetUrl), 301);
+        exit;
+    }
+
     $cookieLang = isset($_COOKIE['ai_translate_lang']) ? strtolower(sanitize_key((string) $_COOKIE['ai_translate_lang'])) : '';
 
@@ -767 +798 @@
 
     // RULE 4: If cookie exists and on root, ensure language is set to default
-    // Skip this rule if there's a search parameter or explicit lang parameter (handled above)
-    $hasExplicitLang = isset($_GET['lang']) && trim((string) $_GET['lang']) !== '';
-    if ($reqPath === '/' && $cookieLang !== '' && !$hasSearchParam && !$hasExplicitLang) {
+    // Skip this rule if there's a search parameter (explicit ?lang= is already handled by RULE 0)
+    if ($reqPath === '/' && $cookieLang !== '' && !$hasSearchParam) {
         \AITranslate\AI_Lang::set_cookie((string) $defaultLang);
         // Set language and stop processing
@@ -1098 +1128 @@
 function cS(r){function n(t){return t?t.trim().replace(/\s+/g," "):""}var s=new Set();var ns=r.querySelectorAll?r.querySelectorAll("input,textarea,select,button,[title],[aria-label],img[alt],.initial-greeting,.chatbot-bot-text"):[];ns.forEach(function(el){if(el.closest?el.closest("[data-ai-trans-skip]"):el.hasAttribute("data-ai-trans-skip"))return;var ph=n(el.getAttribute("placeholder"));if(ph)s.add(ph);var tl=n(el.getAttribute("title"));if(tl)s.add(tl);var al=n(el.getAttribute("aria-label"));if(al)s.add(al);var at=n(el.getAttribute("alt"));if(at)s.add(at);var tg=(el.tagName||"").toLowerCase();if(tg==="input"){var tp=(el.getAttribute("type")||"").toLowerCase();if(tp==="submit"||tp==="button"||tp==="reset"){var v=n(el.getAttribute("value"));if(v)s.add(v);}}var tc=el.textContent;if((el.classList.contains("initial-greeting")||el.classList.contains("chatbot-bot-text"))&&tc){var tcn=n(tc);if(tcn)s.add(tcn);}});return Array.from(s);} 
  function aT(r,m){var ns=r.querySelectorAll?r.querySelectorAll("input,textarea,select,button,[title],[aria-label],img[alt],.initial-greeting,.chatbot-bot-text"):[];ns.forEach(function(el){if(el.closest?el.closest("[data-ai-trans-skip]"):el.hasAttribute("data-ai-trans-skip"))return;var ph=el.getAttribute("placeholder");if(ph){var pht=ph.trim();if(pht&&m[pht]!=null)el.setAttribute("placeholder",m[pht]);}var tl=el.getAttribute("title");if(tl){var tlt=tl.trim();if(tlt&&m[tlt]!=null)el.setAttribute("title",m[tlt]);}var al=el.getAttribute("aria-label");if(al){var alt=al.trim();if(alt&&m[alt]!=null)el.setAttribute("aria-label",m[alt]);}var at=el.getAttribute("alt");if(at){var att=at.trim();if(att&&m[att]!=null)el.setAttribute("alt",m[att]);}var tg=(el.tagName||"").toLowerCase();if(tg==="input"){var tp=(el.getAttribute("type")||"").toLowerCase();if(tp==="submit"||tp==="button"||tp==="reset"){var v=el.getAttribute("value");if(v){var vt=v.trim();if(vt&&m[vt]!=null)el.setAttribute("value",m[vt]);}}}var tc=el.textContent;if((el.classList.contains("initial-greeting")||el.classList.contains("chatbot-bot-text"))&&tc){var tct=tc.trim();if(tct&&m[tct]!=null)el.textContent=m[tct];}});} 
- function tA(r){if(tA.called)return;tA.called=true;var ss=cS(r);if(!ss.length){tA.called=false;return;}var x=new XMLHttpRequest();x.open("POST",AI_TA.u,true);x.setRequestHeader("Content-Type","application/json; charset=UTF-8");x.onreadystatechange=function(){if(x.readyState===4){tA.called=false;if(x.status===200){try{var resp=JSON.parse(x.responseText);if(resp&&resp.success&&resp.data&&resp.data.map){aT(r,resp.data.map);}}catch(e){}}}};x.send(JSON.stringify({nonce:AI_TA.n,lang:gL(),strings:ss}));}
+ function tA(r){if(tA.called)return;tA.called=true;var ua=(typeof navigator!=="undefined"&&navigator.userAgent)?navigator.userAgent:"";if(/googlebot|bingbot|yandexbot|baiduspider|duckduckbot|slurp|facebot|ia_archiver/i.test(ua)){tA.called=false;return;}var ss=cS(r);if(!ss.length){tA.called=false;return;}var x=new XMLHttpRequest();x.open("POST",AI_TA.u,true);x.setRequestHeader("Content-Type","application/json; charset=UTF-8");x.onreadystatechange=function(){if(x.readyState===4){tA.called=false;if(x.status===200){try{var resp=JSON.parse(x.responseText);if(resp&&resp.success&&resp.data&&resp.data.map){aT(r,resp.data.map);}}catch(e){}}}};x.send(JSON.stringify({nonce:AI_TA.n,lang:gL(),strings:ss}));}
 document.addEventListener("DOMContentLoaded",function(){var checkPage=function(){if(document.readyState==="complete"){setTimeout(function(){tA(document);},3000);}else{setTimeout(checkPage,100);}};checkPage();var moT=null,sel="input,textarea,select,button,[title],[aria-label],img[alt],.initial-greeting,.chatbot-bot-text";if(typeof MutationObserver!=="undefined"&&gL()){var mo=new MutationObserver(function(muts){for(var f=false,i=0;i<muts.length&&!f;i++){var a=muts[i].addedNodes;for(var j=0;j<a.length&&!f;j++){var n=a[j];if(n.nodeType===1){if(n.matches&&n.matches(sel))f=true;else if(n.querySelector&&n.querySelector(sel))f=true;}}}if(f){clearTimeout(moT);moT=setTimeout(function(){tA(document);},500);}});mo.observe(document.body||document.documentElement,{childList:true,subtree:true});}});
 })();</script>';
@@ -1173 +1203 @@
         'methods' => 'POST',
         'permission_callback' => function (\WP_REST_Request $request) {
+            // Bot check first: bots get empty response anyway, no need for referer/nonce
+            $ua = isset($_SERVER['HTTP_USER_AGENT']) ? (string) $_SERVER['HTTP_USER_AGENT'] : '';
+            $is_bot = $ua !== '' && preg_match('/googlebot|googleother|bingbot|yandexbot|baiduspider|duckduckbot|slurp|facebot|ia_archiver/i', $ua);
+            if ($is_bot) {
+                $request->set_param('_ai_tr_bot_no_nonce', 1);
+                return true;
+            }
+            // Referer check: must originate from this site
+            $referer = isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : '';
+            if ($referer === '' || strpos($referer, home_url()) !== 0) {
+                return new \WP_Error('rest_forbidden', 'Invalid referer', ['status' => 403]);
+            }
             $nonce = $request->get_header('X-WP-Nonce');
             if ($nonce && wp_verify_nonce($nonce, 'wp_rest')) {
@@ -1185 +1227 @@
         'args' => [],
         'callback' => function (\WP_REST_Request $request) {
+            $is_bot_request = (bool) $request->get_param('_ai_tr_bot_no_nonce');
             // Rate limiting: max 60 requests per minute per IP.
             // This endpoint is called by client-side JavaScript for UI attribute translation.
@@ -1192 +1235 @@
             $rate_key = 'ai_tr_rate_' . md5($ip);
             $rate_count = (int) get_transient($rate_key);
-            if ($rate_count >= 60) {
+            if ($rate_count >= 30) {
                 return new \WP_REST_Response(['error' => 'Rate limit exceeded'], 429);
             }
@@ -1201 +1244 @@
                 $arr = [];
             }
+            // Input limits: max 50 strings of max 150 chars each (UI attributes are short)
+            $arr = array_slice($arr, 0, 50);
+            $arr = array_filter($arr, function ($s) {
+                return is_string($s) && mb_strlen($s) <= 150;
+            });
             // Normalize texts: trim and collapse multiple whitespace to single space
             // Keep mapping between original and normalized for response
@@ -1230 +1278 @@
                 // Fallback: try to detect from Referer header if available (more reliable than current() for REST calls)
                 $referer = isset($_SERVER['HTTP_REFERER']) ? (string) $_SERVER['HTTP_REFERER'] : '';
+                // Normalize referrer: remove double slashes in path (e.g., /de// -> /de/)
+                if ($referer !== '') {
+                    $refererParsed = parse_url($referer);
+                    if (isset($refererParsed['path'])) {
+                        $refererParsed['path'] = preg_replace('#/+#', '/', $refererParsed['path']);
+                        $referer = '';
+                        if (isset($refererParsed['scheme'])) {
+                            $referer .= $refererParsed['scheme'] . '://';
+                        }
+                        if (isset($refererParsed['host'])) {
+                            $referer .= $refererParsed['host'];
+                            if (isset($refererParsed['port'])) {
+                                $referer .= ':' . $refererParsed['port'];
+                            }
+                        }
+                        $referer .= $refererParsed['path'];
+                        if (isset($refererParsed['query'])) {
+                            $referer .= '?' . $refererParsed['query'];
+                        }
+                        if (isset($refererParsed['fragment'])) {
+                            $referer .= '#' . $refererParsed['fragment'];
+                        }
+                    }
+                }
                 if ($referer !== '' && preg_match('#/([a-z]{2})(?:/|$)#i', parse_url($referer, PHP_URL_PATH) ?: '', $m)) {
                     $lang = strtolower($m[1]);
@@ -1258 +1330 @@
             // Batch-strings are UI attributes that should not be translated if stop_translations is enabled
             $stop_translations = isset($settings['stop_translations_except_cache_invalidation']) ? (bool) $settings['stop_translations_except_cache_invalidation'] : false;
-            
-            if ($stop_translations) {
-            }
+            // Bots get cached translations but no API calls (same as stop_translations)
+            $skip_api = $stop_translations || $is_bot_request;
             
             $map = [];
@@ -1315 +1386 @@
                     $cacheInvalid = false;
 
-                    // If stop_translations is enabled, always use cache (don't validate)
-                    if (!$stop_translations) {
+                    // If stop_translations is enabled or bot request, always use cache (don't validate)
+                    if (!$skip_api) {
                         // Validate cache: check if translation is exactly identical to source
                         // NOTE: Identical translations are now accepted as valid (text was already in target language)
@@ -1342 +1413 @@
                     }
 
-                    if ($cacheInvalid && !$stop_translations) {
+                    if ($cacheInvalid && !$skip_api) {
                         // Cache entry is invalid - delete it and re-translate
                         ai_translate_delete_attr_transient($attrCacheKey);
@@ -1357 +1428 @@
                 } else {
                     // Text not in cache
-                    if ($stop_translations) {
-                        // Stop translations enabled: use source text without API call
+                    if ($skip_api) {
+                        // Stop translations or bot: use source text without API call
                         $originalText = isset($textsOriginal[$normalized]) ? $textsOriginal[$normalized] : $normalized;
                         $map[$originalText] = $originalText;
@@ -1382 +1453 @@
             }
             if (!empty($toTranslate)) {
-                if ($stop_translations) {
-                    // Stop translations enabled: block API calls, use source texts
+                if ($skip_api) {
+                    // Stop translations or bot: block API calls, use source texts
                     // Use source texts for all segments that would have been translated
                     foreach ($toTranslate as $id => $origNormalized) {
@@ -1391 +1462 @@
                     // Clear $toTranslate to prevent API call
                     $toTranslate = [];
+                } else {
+                    // Validate that strings actually exist on the page (security: prevent abuse)
+                    $referer = isset($_SERVER['HTTP_REFERER']) ? (string) $_SERVER['HTTP_REFERER'] : '';
+                    // Normalize referrer: remove double slashes in path (e.g., /de// -> /de/)
+                    if ($referer !== '') {
+                        $refererParsed = parse_url($referer);
+                        if (isset($refererParsed['path'])) {
+                            $refererParsed['path'] = preg_replace('#/+#', '/', $refererParsed['path']);
+                            $referer = '';
+                            if (isset($refererParsed['scheme'])) {
+                                $referer .= $refererParsed['scheme'] . '://';
+                            }
+                            if (isset($refererParsed['host'])) {
+                                $referer .= $refererParsed['host'];
+                                if (isset($refererParsed['port'])) {
+                                    $referer .= ':' . $refererParsed['port'];
+                                }
+                            }
+                            $referer .= $refererParsed['path'];
+                            if (isset($refererParsed['query'])) {
+                                $referer .= '?' . $refererParsed['query'];
+                            }
+                            if (isset($refererParsed['fragment'])) {
+                                $referer .= '#' . $refererParsed['fragment'];
+                            }
+                        }
+                    }
+                    if ($referer !== '' && strpos($referer, home_url()) === 0) {
+                        // Get page HTML (cached using same expiration as translations)
+                        $page_cache_key = 'ai_tr_page_html_' . md5($referer);
+                        $page_html = get_transient($page_cache_key);
+                        if ($page_html === false) {
+                            // Fetch page HTML
+                            $response = wp_remote_get($referer, array(
+                                'timeout' => 5,
+                                'sslverify' => false,
+                                'headers' => array(
+                                    'User-Agent' => 'AI-Translate-Validator/1.0'
+                                )
+                            ));
+                            if (!is_wp_error($response) && wp_remote_retrieve_response_code($response) === 200) {
+                                $page_html = wp_remote_retrieve_body($response);
+                                // Cache using same expiration as translations
+                                $expiry_hours = isset($settings['cache_expiration']) ? (int) $settings['cache_expiration'] : (14 * 24);
+                                $expiry = max(1, $expiry_hours) * HOUR_IN_SECONDS;
+                                set_transient($page_cache_key, $page_html, $expiry);
+                            } else {
+                                // Security: if page HTML cannot be fetched, block translation to prevent abuse
+                                $toTranslate = [];
+                            }
+                        }
+                        // Validate each string exists on page (in attributes or content)
+                        if ($page_html !== '') {
+                            $validated = [];
+                            foreach ($toTranslate as $id => $text) {
+                                // Check if string exists in HTML (escape special regex chars)
+                                $text_escaped = preg_quote($text, '/');
+                                // Match in attributes (placeholder, title, aria-label, alt, value) or content
+                                if (preg_match('/' . $text_escaped . '/iu', $page_html)) {
+                                    $validated[$id] = $text;
+                                }
+                            }
+                            // Only allow translation of validated strings
+                            $toTranslate = $validated;
+                        } else {
+                            // Security: if page HTML is empty, block translation to prevent abuse
+                            $toTranslate = [];
+                        }
+                    } else {
+                        // Security: if referer is invalid or missing, block translation
+                        $toTranslate = [];
+                    }
                 }
             }
@@ -1639 +1782 @@
     // Check if path contains a post type prefix (e.g., service/slug)
     $slug_used_for_lookup = null;
+    $detected_post_type = null;
     if (strpos($rest, '/') !== false) {
         $parts = explode('/', $rest, 2);
         if (count($parts) === 2) {
             $potential_post_type = $parts[0];
-            $potential_slug = $parts[1];
+            $potential_slug = trim($parts[1], '/');
             $slug_used_for_lookup = $potential_slug;
 
             // Check if this is a registered post type
             if (post_type_exists($potential_post_type)) {
+                $detected_post_type = $potential_post_type;
+                // If slug is empty (only post type, e.g., /it/service/), redirect to language root
+                if ($potential_slug === '') {
+                    nocache_headers();
+                    wp_redirect(home_url('/' . $lang . '/'), 301);
+                    exit;
+                }
                 $post_id = \AITranslate\AI_Slugs::resolve_path_to_post($lang, $potential_slug);
                 if ($post_id) {
@@ -1659 +1810 @@
                 }
             }
+        }
+    } else {
+        // Single segment: check if it's a post type without slug (e.g., /it/service)
+        if (post_type_exists($rest)) {
+            $detected_post_type = $rest;
+            // Post type without slug, redirect to language root
+            nocache_headers();
+            wp_redirect(home_url('/' . $lang . '/'), 301);
+            exit;
         }
     }
@@ -1824 +1984 @@
         }
     }
+
+    // No resolution found for this language-prefixed URL.
+    // Remove the rewrite-generated pagename (e.g. "es/bestaat-niet") to prevent
+    // WordPress from falling back to the blog index instead of properly triggering a 404.
+    unset($wp->query_vars['pagename']);
+    $wp->query_vars['error'] = '404';
 });
 
@@ -2248 +2414 @@
         return;
     }
+
+    // Rate limiting: max 10 search queries per minute per IP (prevent abuse/cost attacks)
+    // Normal users rarely exceed 1-2 searches per minute; 5 is generous but prevents abuse
+    $ip = isset($_SERVER['REMOTE_ADDR']) ? sanitize_text_field($_SERVER['REMOTE_ADDR']) : 'unknown';
+    $rate_key = 'ai_tr_search_rate_' . md5($ip);
+    $rate_count = (int) get_transient($rate_key);
+    if ($rate_count >= 10) {
+        // Rate limit exceeded: skip translation, use original query
+        return;
+    }
+    set_transient($rate_key, $rate_count + 1, 60);
 
     $settings = get_option('ai_translate_settings', array());

ai-translate/trunk/includes/admin-page.php

@@ -129 +129 @@
     $post_id = intval($raw_post_id);
     
-    if ($post_id < 0) {
+    if ($post_id < -1) {
         wp_send_json_error(['message' => __('Invalid post ID.', 'ai-translate')]);
         return;
     }
     
-    // For homepage (post_id = 0), skip post verification
+    // For homepage (post_id = 0) and 404 page (post_id = -1), skip post verification
     if ($post_id > 0) {
         // Verify post exists and user has permission to access it
@@ -318 +318 @@
         $front_page_id = (int) get_option('page_on_front');
         return ($front_page_id > 0) ? ('post:' . $front_page_id) : ('path:' . md5('/'));
+    }
+    if ($post_id === -1) {
+        return 'path:' . md5('/404');
     }
     return 'post:' . $post_id;
@@ -416 +419 @@
         }
         
-        // Check if response looks like an error page (404, 403, etc.)
+        // Check if response looks like an error page (403, 500, etc.)
         $is_error_page = false;
-        if ($http_code === 200 && !empty($response_body)) {
-            // Check for common error indicators in HTML
+        if ($http_code === 200 && !empty($response_body) && $post_id !== -1) {
+            // Check for common error indicators in HTML (skip for 404 pages which are expected)
             if (stripos($response_body, '<title>404') !== false || 
                 stripos($response_body, 'page not found') !== false ||
@@ -428 +431 @@
         }
         
-        // Accept 200 as success (unless it's an error page)
-        if ($http_code === 200 && !$is_error_page) {
+        // Accept 200 as success (unless it's an error page), and 404 for 404 page warming
+        $is_success = ($http_code === 200 && !$is_error_page) || ($post_id === -1 && $http_code === 404);
+        if ($is_success) {
             // Wait a moment for async cache writes to complete
             usleep(500000); // 0.5 second
@@ -658 +662 @@
     $post_id = intval($raw_post_id);
     
-    if ($post_id < 0) {
+    if ($post_id < -1) {
         wp_send_json_error(['message' => __('Invalid post ID.', 'ai-translate')]);
         return;
     }
     
-    // For homepage (post_id = 0), skip post verification
+    // For homepage (post_id = 0) and 404 page (post_id = -1), skip post verification
     if ($post_id > 0) {
         // Verify post exists and user has permission to access it
@@ -692 +696 @@
     }
     
-    // Get post URL (homepage uses home_url)
+    // Get post URL (homepage uses home_url, 404 uses a non-existent path to trigger 404)
     if ($post_id === 0) {
         $post_url = home_url('/');
+    } elseif ($post_id === -1) {
+        // 404 page: use a non-existent path that will trigger a 404
+        $post_url = home_url('/ait-404-cache-warm/');
     } else {
         $post_url = get_permalink($post_id);

ai-translate/trunk/includes/class-ai-cache-meta.php

@@ -77 +77 @@
         $sql = "CREATE TABLE IF NOT EXISTS $table_name (
             id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
-            post_id BIGINT UNSIGNED NOT NULL,
+            post_id BIGINT NOT NULL,
             language_code VARCHAR(10) NOT NULL,
             cache_file VARCHAR(255) NOT NULL,
@@ -486 +486 @@
             array_unshift($results, $homepage_obj);
         }
+
+        // Add 404 page row (always show on first page, even if no cache yet - similar to homepage)
+        if ($offset === 0) {
+            $error404_cached = (int) $wpdb->get_var($wpdb->prepare(
+                "SELECT COUNT(DISTINCT language_code) FROM " . $table_name . " WHERE post_id = %d",
+                -1
+            ));
+            $error404_obj = new \stdClass();
+            $error404_obj->ID = -1;
+            $error404_obj->post_type = '404';
+            $error404_obj->post_title = __('404 Page', 'ai-translate');
+            $error404_obj->cached_languages = $error404_cached;
+            $error404_obj->total_languages = $total_languages;
+            $error404_obj->percentage = $total_languages > 0
+                ? round(($error404_cached / $total_languages) * 100)
+                : 0;
+            $error404_obj->url = home_url('/404');
+            $results[] = $error404_obj;
+        }
         
         // Add percentage and URL
@@ -649 +668 @@
                     
                     $post_id = (int) $row->post_id;
-                    $title = $post_id === 0 ? __('Homepage', 'ai-translate') : get_the_title($post_id);
+                    $title = $post_id === 0 ? __('Homepage', 'ai-translate') : ($post_id === -1 ? __('404 Page', 'ai-translate') : get_the_title($post_id));
                     if ($title === '') {
                         $title = sprintf(__('Post %d', 'ai-translate'), $post_id);
@@ -779 +798 @@
         if ($post_id === 0) {
             $path = '/';
+        } elseif ($post_id === -1) {
+            // 404 page - no real permalink
+            return home_url('/' . $lang . '/404/');
         } else {
             $permalink = get_permalink($post_id);

ai-translate/trunk/includes/class-ai-cache.php

@@ -134 +134 @@
                 $post_id = 0;
             }
+            // Check if route_id is the 404 page (path:md5(/404))
+            elseif ($route_id === ('path:' . md5('/404'))) {
+                // Use post_id = -1 for 404 page
+                $post_id = -1;
+            }
             
             if ($post_id !== null) {

ai-translate/trunk/includes/class-ai-ob.php

@@ -679 +679 @@
         }
         
+        // For 404 pages: use a single consistent route_id so all 404s share one cache entry per language
+        if (function_exists('is_404') && is_404()) {
+            return 'path:' . md5('/404');
+        }
+
         // CRITICAL: For warm cache requests and translated URLs, resolve the post ID from the URL FIRST
         // This is needed because WordPress query functions (is_singular, get_queried_object_id) 
@@ -878 +883 @@
     private function should_skip_content_type($html)
     {
-        // Skip 404 pages - multiple detection methods
+        // Skip 404 pages - but allow translation when a non-default language is active
+        // Users encountering a 404 in another language should see translated error messages
         if ($this->is_404_page($html)) {
-            return true;
+            $lang = AI_Lang::current();
+            if ($lang === null || !AI_Lang::should_translate($lang)) {
+                return true;
+            }
+            // Non-default language active: allow 404 through for translation
         }
 
@@ -907 +917 @@
     private function should_skip_page_structure()
     {
-        // Only translate singular posts/pages, with exceptions for search/homepage
+        // Only translate singular posts/pages, with exceptions for search/homepage/404
         if (function_exists('is_singular') && !is_singular()) {
             $is_search = function_exists('is_search') && is_search();
             $is_front_page = function_exists('is_front_page') && is_front_page();
-            if (!$is_search && !$is_front_page) {
+            $is_404 = function_exists('is_404') && is_404();
+            if (!$is_search && !$is_front_page && !$is_404) {
                 return true;
             }
@@ -1222 +1233 @@
             }
             if (function_exists('is_front_page') && is_front_page()) {
+                return true;
+            }
+            // Cache translated 404 pages - always same content, avoids repeated API calls
+            if (function_exists('is_404') && is_404()) {
                 return true;
             }

ai-translate/trunk/includes/class-ai-seo.php

@@ -745 +745 @@
         }
 
+        // 404 page: use a non-existent path to trigger a 404 response
+        if ((int) $post_id === -1) {
+            return home_url('/' . $lang . '/ait-404-cache-warm/');
+        }
+
         $translatedSlug = AI_Slugs::get_or_generate((int) $post_id, $lang);
         if ($translatedSlug !== null && $translatedSlug !== '') {