Files
chill.social/themes/chill-theme/static/js/language-preference.js
2026-01-28 09:40:37 +01:00

333 lines
12 KiB
JavaScript

/**
* Language Preference Manager
* Stores user's language selection in localStorage and auto-redirects on subsequent visits
* Supports automatic language detection via VisitorAPI
*/
(function() {
'use strict';
// Configuration
const STORAGE_KEY = 'hugo_preferred_language';
const SESSION_KEY = 'language_redirected';
// Get VisitorAPI project ID from Hugo config (injected via template)
const VISITOR_API_PID = window.HUGO_VISITOR_API_PID || null;
/**
* Initialize the language preference system
*/
function init() {
// Check and redirect on page load (before DOM ready for faster redirect)
checkAndRedirect();
// Attach click handlers after DOM is ready
if (document.readyState === 'loading') {
document.addEventListener('DOMContentLoaded', attachLanguageSwitchers);
} else {
attachLanguageSwitchers();
}
}
/**
* Check if we should redirect to user's preferred language
*/
function checkAndRedirect() {
try {
const preferredLang = getStoredLanguage();
const currentLang = getCurrentLanguage();
console.log('Language preference check:', {
preferredLang: preferredLang || 'none',
currentLang: currentLang,
visitorApiConfigured: !!VISITOR_API_PID
});
// If user has a stored preference and it matches current language, we're good
if (preferredLang && preferredLang === currentLang) {
console.log('Language preference: Already on preferred language:', currentLang);
return;
}
// If user has a stored preference, use it
if (preferredLang && preferredLang !== currentLang && isValidLanguage(preferredLang)) {
console.log('Language preference: Redirecting to stored preference:', preferredLang);
redirectToLanguage(preferredLang);
return;
}
// If no stored preference and VisitorAPI is configured, call it every time
if (!preferredLang && VISITOR_API_PID) {
detectLanguageViaVisitorAPI();
} else if (!preferredLang) {
console.log('Language preference: No stored preference and VisitorAPI not configured');
}
} catch (e) {
// Silently fail if localStorage/sessionStorage is unavailable
console.warn('Language preference: Storage unavailable', e);
}
}
/**
* Detect user's language using VisitorAPI
*/
function detectLanguageViaVisitorAPI() {
console.log('VisitorAPI: Calling API to detect language...');
// VisitorAPI implementation
var VisitorAPI = function(projectId, successCallback, errorCallback) {
var xhr = new XMLHttpRequest();
xhr.onreadystatechange = function() {
if (xhr.readyState === XMLHttpRequest.DONE) {
try {
var response = JSON.parse(xhr.responseText);
if (response.status === 200) {
successCallback(response.data);
} else {
errorCallback(response.status, response.result);
}
} catch (e) {
errorCallback(0, 'Failed to parse response');
}
}
};
xhr.open("GET", "https://api.visitorapi.com/api/?pid=" + projectId);
xhr.send(null);
};
// Call VisitorAPI
VisitorAPI(
VISITOR_API_PID,
function(data) {
handleVisitorAPISuccess(data);
},
function(errorCode, errorMessage) {
console.warn('VisitorAPI error:', errorCode, errorMessage);
}
);
}
/**
* Handle successful VisitorAPI response
* @param {Object} data - VisitorAPI response data
*/
function handleVisitorAPISuccess(data) {
console.log('VisitorAPI: Received data:', data);
// Get languages from response (e.g., ["en", "eng"])
var languages = data.languages || [];
if (languages.length === 0) {
console.log('VisitorAPI: No languages detected in response');
return;
}
console.log('VisitorAPI: Detected languages:', languages);
// Get current language to check if already on preferred language
var currentLang = getCurrentLanguage();
console.log('VisitorAPI: Current language:', currentLang);
// Get all available Hugo language codes from the page
var availableHugoLangs = [];
var languageLinks = document.querySelectorAll('.language-switch-link');
for (var i = 0; i < languageLinks.length; i++) {
var hugoLang = languageLinks[i].getAttribute('data-lang');
if (hugoLang) {
availableHugoLangs.push(hugoLang.toLowerCase());
}
}
// Add current language to available languages if not already present
// This handles the case where default language (e.g., "en") might not have a visible switch link
if (currentLang && availableHugoLangs.indexOf(currentLang) === -1) {
availableHugoLangs.unshift(currentLang); // Add to beginning of array
console.log('VisitorAPI: Added current language to available languages:', currentLang);
}
console.log('VisitorAPI: Available Hugo languages:', availableHugoLangs);
// Try to match visitor's language to available Hugo languages
// Match using first 2 characters of language code (e.g., "en" matches "en", "zh" matches "zh-cn")
// IMPORTANT: Iterate through visitor's languages IN ORDER to respect preference
var detectedLang = null;
for (var i = 0; i < languages.length; i++) {
var visitorLang = languages[i].toLowerCase();
// Get first 2 characters of the visitor's language code
var langPrefix = visitorLang.substring(0, 2);
console.log('VisitorAPI: Checking visitor language:', visitorLang, '(prefix: ' + langPrefix + ')');
// Check if any available Hugo language matches this visitor language
for (var j = 0; j < availableHugoLangs.length; j++) {
var hugoLang = availableHugoLangs[j];
// Get first 2 characters of Hugo language code
var hugoPrefix = hugoLang.substring(0, 2);
// Match based on first 2 characters
if (langPrefix === hugoPrefix) {
detectedLang = hugoLang;
console.log('VisitorAPI: Matched language:', visitorLang, '(' + langPrefix + ') -> Hugo language:', hugoLang);
break;
}
}
// Break immediately when first match is found (respects visitor's language preference order)
if (detectedLang) {
break;
}
}
// If we detected a valid language and it's different from current, redirect
if (detectedLang) {
console.log('VisitorAPI: Detected lang:', detectedLang, 'Current lang:', currentLang);
if (detectedLang !== currentLang) {
console.log('VisitorAPI: Storing preference and redirecting to:', detectedLang);
// Store the detected language as preference
setStoredLanguage(detectedLang);
// Redirect to detected language
redirectToLanguage(detectedLang);
} else {
console.log('VisitorAPI: Already on detected language, no redirect needed');
// Store the preference even if we're already on the right language
setStoredLanguage(detectedLang);
}
} else {
console.log('VisitorAPI: No matching Hugo language found for detected languages');
}
}
/**
* Attach click event listeners to all language switch links
*/
function attachLanguageSwitchers() {
const links = document.querySelectorAll('.language-switch-link');
links.forEach(function(link) {
link.addEventListener('click', handleLanguageClick);
});
}
/**
* Handle click on language switch link
* @param {Event} e - Click event
*/
function handleLanguageClick(e) {
const lang = e.currentTarget.getAttribute('data-lang');
if (lang) {
try {
setStoredLanguage(lang);
console.log('Language preference: Stored user preference:', lang);
} catch (e) {
console.warn('Language preference: Could not save preference', e);
}
}
// Let the link navigate normally (don't prevent default)
}
/**
* Get the stored language preference from localStorage
* @returns {string|null} Language code or null
*/
function getStoredLanguage() {
try {
return localStorage.getItem(STORAGE_KEY);
} catch (e) {
return null;
}
}
/**
* Store the language preference in localStorage
* @param {string} lang - Language code to store
*/
function setStoredLanguage(lang) {
try {
localStorage.setItem(STORAGE_KEY, lang);
} catch (e) {
throw e;
}
}
/**
* Get the current language from the URL path
* @returns {string} Current language code (e.g., 'en', 'zh-cn')
*/
function getCurrentLanguage() {
const path = window.location.pathname;
// Match language code pattern: /en/ or /zh-cn/ at start of path
const match = path.match(/^\/([a-z]{2}(-[a-z]{2})?)\//i);
if (match) {
return match[1].toLowerCase();
}
// If no language in path, assume default language (root path)
// This handles cases like "/" which might be the default language
return getDefaultLanguage();
}
/**
* Get default language from HTML lang attribute or fallback
* @returns {string} Default language code
*/
function getDefaultLanguage() {
const htmlLang = document.documentElement.getAttribute('lang');
if (htmlLang) {
// Extract primary language code (e.g., 'en-US' -> 'en')
return htmlLang.split('-')[0].toLowerCase();
}
return 'en'; // Fallback
}
/**
* Check if a language code is valid by looking for available language links
* @param {string} lang - Language code to validate
* @returns {boolean} True if valid
*/
function isValidLanguage(lang) {
// Check if any language switch link exists for this language
const link = document.querySelector('.language-switch-link[data-lang="' + lang + '"]');
return link !== null;
}
/**
* Redirect to a specific language, preserving the current path
* @param {string} targetLang - Target language code
*/
function redirectToLanguage(targetLang) {
const currentPath = window.location.pathname;
const currentLang = getCurrentLanguage();
const search = window.location.search;
const hash = window.location.hash;
let newPath;
// Check if current path has a language prefix
if (currentPath.match(/^\/[a-z]{2}(-[a-z]{2})?\//i)) {
// Replace existing language: /en/about -> /zh-cn/about
newPath = currentPath.replace(
/^\/[a-z]{2}(-[a-z]{2})?\//i,
'/' + targetLang + '/'
);
} else {
// Add language prefix: /about -> /zh-cn/about
newPath = '/' + targetLang + currentPath;
}
// Perform redirect
window.location.href = newPath + search + hash;
}
// Initialize when script loads
init();
})();