@inlang/paraglide-js/dist/compiler/runtime/extract-locale-from-url.js

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import { assertIsLocale } from "./assert-is-locale.js";
import { isLocale } from "./is-locale.js";
import { baseLocale, TREE_SHAKE_DEFAULT_URL_PATTERN_USED, urlPatterns, } from "./variables.js";
/**
 * If extractLocaleFromUrl is called many times on the same page and the URL
 * hasn't changed, we don't need to recompute it every time which can get expensive.
 * We might use a LRU cache if needed, but for now storing only the last result is enough.
 * https://github.com/opral/monorepo/pull/3575#discussion_r2066731243
 */
/** @type {string|undefined} */
let cachedUrl;
/** @type {Locale|undefined} */
let cachedLocale;
/**
 * Extracts the locale from a given URL using native URLPattern.
 *
 * @param {URL|string} url - The full URL from which to extract the locale.
 * @returns {Locale|undefined} The extracted locale, or undefined if no locale is found.
 */
export function extractLocaleFromUrl(url) {
    const urlString = typeof url === "string" ? url : url.href;
    if (cachedUrl === urlString) {
        return cachedLocale;
    }
    let result;
    if (TREE_SHAKE_DEFAULT_URL_PATTERN_USED) {
        result = defaultUrlPatternExtractLocale(url);
    }
    else {
        const urlObj = typeof url === "string" ? new URL(url) : url;
        // Iterate over URL patterns
        for (const element of urlPatterns) {
            for (const [locale, localizedPattern] of element.localized) {
                const match = new URLPattern(localizedPattern, urlObj.href).exec(urlObj.href);
                if (!match) {
                    continue;
                }
                // Check if the locale is valid
                if (assertIsLocale(locale)) {
                    result = locale;
                    break;
                }
            }
            if (result)
                break;
        }
    }
    cachedUrl = urlString;
    cachedLocale = result;
    return result;
}
/**
 * https://github.com/opral/inlang-paraglide-js/issues/381
 *
 * @param {URL|string} url - The full URL from which to extract the locale.
 * @returns {Locale|undefined} The extracted locale, or undefined if no locale is found.
 */
function defaultUrlPatternExtractLocale(url) {
    const urlObj = new URL(url, "http://dummy.com");
    const pathSegments = urlObj.pathname.split("/").filter(Boolean);
    if (pathSegments.length > 0) {
        const potentialLocale = pathSegments[0];
        if (isLocale(potentialLocale)) {
            return potentialLocale;
        }
    }
    // everything else has to be the base locale
    return baseLocale;
}