Automatically redirects URLs to their preferred language equivalents
// ==UserScript==
// @name GoLocale
// @namespace https://github.com/tonioriol
// @version 0.4.0
// @description Automatically redirects URLs to their preferred language equivalents
// @author Toni Oriol
// @match *://*/*
// @grant GM.getValue
// @grant GM.setValue
// @license AGPL-3.0-or-later
// ==/UserScript==
// Configuration groups
const LANGUAGE_CONFIG = {
targetLang: "ca",
altLang: "va"
};
const DETECTION_CONFIG = {
urlParams: ["lang", "ln", "hl"]
};
// Utility functions
const getBaseDomain = (hostname) => {
const parts = hostname.split('.');
if (parts.length >= 3 && parts[0].length >= 2 && parts[0].length <= 3) {
const possibleLangCode = parts[0].toLowerCase();
if (/^[a-z]{2,3}$/.test(possibleLangCode)) {
return parts.slice(1).join('.');
}
}
return hostname;
};
const getStorageKey = (domain, type) => `golocale_${type}_${getBaseDomain(domain)}`;
const notify = (message, buttonText, callback) => {
document.getElementById('golocale-notify')?.remove();
const notification = document.createElement('div');
notification.id = 'golocale-notify';
notification.innerHTML = `
<div
style="position: fixed; top: 10px; right: 10px; z-index: 999999; padding: 12px 12px 12px 32px; background: #333; color: white; border-radius: 4px; font: 14px sans-serif; ${!buttonText ? 'cursor: pointer;' : ''}"
${!buttonText ? 'onclick="this.parentElement.remove()"' : ''}>
<button
style="position: absolute; left: 8px; top: 50%; transform: translateY(-50%); width: 16px; height: 16px; background: #666; color: white; border: none; border-radius: 0; cursor: pointer; font-size: 14px; display: flex; align-items: center; justify-content: center;"
onclick="this.parentElement.parentElement.remove()">
×
</button>
<span>${message}</span>
${buttonText ? `
<button
class="golocale-action-btn"
style="margin-left: 8px; padding: 4px 8px; background: #666; color: white; border: none; border-radius: 3px; cursor: pointer;">
${buttonText}
</button>
` : ''}
</div>
`;
// Add event listener for action button
if (buttonText && callback) {
const actionBtn = notification.querySelector('.golocale-action-btn');
actionBtn.onclick = () => {
notification.remove();
callback();
};
}
document.body.appendChild(notification);
setTimeout(() => notification.remove?.(), 30000);
};
const isTargetLanguage = (html) => {
const targetLangs = [LANGUAGE_CONFIG.targetLang, LANGUAGE_CONFIG.altLang].filter(Boolean);
console.log("[GoLocale] Checking if page is in target languages:", targetLangs);
// Check HTML lang attribute first
const langAttr = html.match(/<html[^>]*lang=["']([^"']*)/i);
const lang = langAttr?.[1]?.toLowerCase();
console.log("[GoLocale] HTML lang attribute found:", lang);
const langCode = lang?.split("-")[0];
if (targetLangs.includes(lang) || targetLangs.includes(langCode)) {
console.log("[GoLocale] Page is already in target language (HTML attribute)");
return true;
}
if (lang && !targetLangs.includes(langCode)) {
console.log("[GoLocale] HTML lang attribute indicates different language, not using franc detection");
return false;
}
// Use franc detection as fallback
const detectedLang = francDetect(html);
console.log("[GoLocale] Franc detected language code:", detectedLang);
const mappedLang = iso6393To1[detectedLang];
console.log("[GoLocale] Mapped to 2-letter code:", mappedLang);
if (targetLangs.includes(mappedLang)) {
console.log("[GoLocale] Page is in target language (detected by franc)");
return true;
}
console.log("[GoLocale] Page is NOT in target language");
return false;
};
const fetchAndCheckLanguage = async (url) => {
console.log("[GoLocale] Testing URL candidate:", url);
try {
const response = await fetch(url);
console.log("[GoLocale] Response status:", response.status);
if (response.status >= 400) {
console.log("[GoLocale] URL failed with status >= 400");
return false;
}
const html = await response.text();
console.log("[GoLocale] Fetched HTML length:", html.length);
const result = isTargetLanguage(html);
console.log("[GoLocale] URL candidate result:", result);
return result;
} catch (error) {
console.error("[GoLocale] Error fetching URL:", url, error);
// Try no-cors fallback
console.log("[GoLocale] Trying no-cors fallback");
try {
const noCorsResponse = await fetch(url, { mode: "no-cors" });
console.log("[GoLocale] No-cors response type:", noCorsResponse.type);
if (noCorsResponse.type === "opaque") {
console.log("[GoLocale] No-cors succeeded, assuming URL is valid");
return true;
}
} catch (noCorsError) {
console.error("[GoLocale] No-cors fallback also failed:", noCorsError);
}
return false;
}
};
// URL generation strategies
const replaceLanguageCodes = (url, targetLang) => {
const currentLangMap = typeof window !== 'undefined' ? window.langMap : global.langMap;
const target = currentLangMap.get(targetLang);
if (!target) {
console.log("[GoLocale] Language not in ISO map, using pattern replacement for:", targetLang);
return url.replace(/\/([a-z]{2,3})\//g, (match, langCode) => {
return currentLangMap.has(langCode.toLowerCase()) ? `/${targetLang}/` : match;
});
}
return url.replace(/(?<!\.)\b([a-z]{2,3})\b/gi, (match) => {
const found = currentLangMap.get(match.toLowerCase());
return found
? found.iso6391 === match.toLowerCase()
? target.iso6391 || match
: found.iso6392B === match.toLowerCase()
? target.iso6392B || match
: found.iso6392T === match.toLowerCase()
? target.iso6392T || match
: match
: match;
});
};
const injectPath = (url, targetLang) => {
const u = new URL(url);
u.pathname = `/${targetLang}${u.pathname}`;
return u.toString();
};
const replaceSubdomain = (url, targetLang) => {
const u = new URL(url);
const hostParts = u.hostname.split(".");
const currentLangMap = typeof window !== 'undefined' ? window.langMap : global.langMap;
if (hostParts.length >= 2 && currentLangMap.has(hostParts[0].toLowerCase())) {
console.log("[GoLocale] Replacing subdomain language code:", hostParts[0], "with", targetLang);
hostParts[0] = targetLang;
u.hostname = hostParts.join(".");
return u.toString();
}
return null;
};
const injectSubdomain = (url, targetLang) => {
const u = new URL(url);
u.hostname = `${targetLang}.${u.hostname}`;
return u.toString();
};
const injectParams = (url, targetLang) => {
return DETECTION_CONFIG.urlParams.map((param) => {
const u = new URL(url);
u.searchParams.set(param, targetLang);
return u.toString();
});
};
const generateUrlCandidates = (url) => {
console.log("[GoLocale] Generating URL candidates for:", url);
const candidates = [];
const targetLangs = [LANGUAGE_CONFIG.targetLang, LANGUAGE_CONFIG.altLang].filter(Boolean);
for (const targetLang of targetLangs) {
console.log("[GoLocale] Generating candidates for language:", targetLang);
// Strategy 1: Replace existing language codes
candidates.push(replaceLanguageCodes(url, targetLang));
// Strategy 2: Replace subdomain language codes
const replacedSubdomainUrl = replaceSubdomain(url, targetLang);
if (replacedSubdomainUrl) {
candidates.push(replacedSubdomainUrl);
}
// Strategy 3: Path injection
candidates.push(injectPath(url, targetLang));
// Strategy 4: Subdomain injection
candidates.push(injectSubdomain(url, targetLang));
// Strategy 5: URL parameter injection
candidates.push(...injectParams(url, targetLang));
}
console.log("[GoLocale] Total candidates generated:", candidates.length);
return candidates;
};
const handleNotification = async () => {
if (await GM.getValue("notify", false)) {
await GM.setValue("notify", false);
notify("GoLocale Redirected", "Stop", async () => {
await GM.setValue(getStorageKey(location.hostname, 'user_disabled'), true);
console.log("[GoLocale] User disabled redirects for domain:", getBaseDomain(location.hostname));
});
}
};
const tryRedirect = async () => {
const url = location.href;
console.log("[GoLocale] Starting redirect attempt for:", url);
// Check if user has disabled redirects for this domain
const userDisabledKey = getStorageKey(location.hostname, 'user_disabled');
const userDisabled = await GM.getValue(userDisabledKey, false);
if (userDisabled) {
console.log("[GoLocale] Skipping - user disabled redirects for this domain");
setTimeout(() => {
if (!document.querySelector('[data-golocale]')) {
notify("Redirects Disabled", "Enable", async () => {
await GM.setValue(userDisabledKey, false);
console.log("[GoLocale] Re-enabled redirects for domain:", getBaseDomain(location.hostname));
notify("Redirects enabled!");
});
}
}, 1000);
return;
}
// Check if current page is already in target language
console.log("[GoLocale] Checking current page language...");
const currentPageHtml = document.documentElement.outerHTML;
if (isTargetLanguage(currentPageHtml)) {
console.log("[GoLocale] Current page is already in target language, no redirect needed");
return;
}
const candidates = generateUrlCandidates(url);
const filteredCandidates = candidates.filter((c) => c !== url);
console.log("[GoLocale] Filtered candidates (excluding original URL):", filteredCandidates);
// Test each candidate URL
for (let i = 0; i < filteredCandidates.length; i++) {
const candidate = filteredCandidates[i];
console.log(`[GoLocale] Testing candidate ${i + 1}/${filteredCandidates.length}:`, candidate);
if (await fetchAndCheckLanguage(candidate)) {
console.log("[GoLocale] Found working candidate! Redirecting to:", candidate);
await GM.setValue("notify", true);
console.log("[GoLocale] Notification flag set");
location.href = candidate;
return;
}
}
console.log("[GoLocale] No suitable candidates found, staying on current page");
};
// Main execution
(async () => {
console.log("[GoLocale] Script starting...");
if (typeof window === "undefined" || window !== window.top) {
console.log("[GoLocale] Skipping - not in top-level window");
return;
}
// Dynamic imports
console.log("[GoLocale] Loading language detection libraries...");
const { franc: francDetect } = await import("https://cdn.jsdelivr.net/npm/[email protected]/+esm");
const { iso6393: iso6393Data, iso6393To1 } = await import("https://cdn.jsdelivr.net/npm/[email protected]/+esm");
console.log("[GoLocale] Libraries loaded successfully");
// Create language map for O(1) lookups
window.langMap = new Map(
iso6393Data.flatMap((lang) =>
[lang.iso6391, lang.iso6392B, lang.iso6392T]
.filter(Boolean)
.map((code) => [code.toLowerCase(), lang])
)
);
console.log("[GoLocale] Adding load event listener for notifications");
window.addEventListener("load", async () => {
await handleNotification();
console.log("[GoLocale] Starting redirect process...");
await tryRedirect();
console.log("[GoLocale] Redirect process completed");
});
})();
// Export functions for testing using CommonJS
if (typeof module !== 'undefined' && module.exports) {
module.exports = {
replaceLanguageCodes,
injectPath,
injectSubdomain,
injectParams,
isTargetLanguage
};
}