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694/**
* next/router shim
*
* Provides useRouter() hook and Router singleton for Pages Router.
* Backed by the browser History API. Supports client-side navigation
* by fetching new page data and re-rendering the React root.
*/
import { useState, useEffect, useCallback, useMemo } from "react";
import { isValidModulePath } from "../client/validate-module-path.js";
/** basePath from next.config.js, injected by the plugin at build time */
const __basePath: string = process.env.__NEXT_ROUTER_BASEPATH ?? "";
/** Prepend basePath to a path for browser URLs / fetches */
function withBasePath(p: string): string {
if (!__basePath) return p;
return __basePath + p;
}
/** Strip basePath prefix from a browser pathname */
function stripBasePath(p: string): string {
if (!__basePath) return p;
if (p.startsWith(__basePath)) return p.slice(__basePath.length) || "/";
return p;
}
type BeforePopStateCallback = (state: { url: string; as: string; options: { shallow: boolean } }) => boolean;
interface NextRouter {
/** Current pathname */
pathname: string;
/** Current route pattern (e.g., "/posts/[id]") */
route: string;
/** Query parameters */
query: Record<string, string | string[]>;
/** Full URL including query string */
asPath: string;
/** Base path */
basePath: string;
/** Current locale */
locale?: string;
/** Available locales */
locales?: string[];
/** Default locale */
defaultLocale?: string;
/** Whether the router is ready */
isReady: boolean;
/** Whether this is a preview */
isPreview: boolean;
/** Whether this is a fallback page */
isFallback: boolean;
/** Navigate to a new URL */
push(url: string | UrlObject, as?: string, options?: TransitionOptions): Promise<boolean>;
/** Replace current URL */
replace(url: string | UrlObject, as?: string, options?: TransitionOptions): Promise<boolean>;
/** Go back */
back(): void;
/** Reload the page */
reload(): void;
/** Prefetch a page (injects <link rel="prefetch">) */
prefetch(url: string): Promise<void>;
/** Register a callback to run before popstate navigation */
beforePopState(cb: BeforePopStateCallback): void;
/** Listen for route changes */
events: RouterEvents;
}
interface UrlObject {
pathname?: string;
query?: Record<string, string>;
}
interface TransitionOptions {
shallow?: boolean;
scroll?: boolean;
locale?: string;
}
// Route event handler types (used by consumers via router.events)
type _RouteChangeHandler = (url: string) => void;
type _RouteErrorHandler = (err: Error, url: string) => void;
interface RouterEvents {
on(event: string, handler: (...args: unknown[]) => void): void;
off(event: string, handler: (...args: unknown[]) => void): void;
emit(event: string, ...args: unknown[]): void;
}
function createRouterEvents(): RouterEvents {
const listeners = new Map<string, Set<(...args: unknown[]) => void>>();
return {
on(event: string, handler: (...args: unknown[]) => void) {
if (!listeners.has(event)) listeners.set(event, new Set());
listeners.get(event)!.add(handler);
},
off(event: string, handler: (...args: unknown[]) => void) {
listeners.get(event)?.delete(handler);
},
emit(event: string, ...args: unknown[]) {
listeners.get(event)?.forEach((handler) => handler(...args));
},
};
}
// Singleton events instance
const routerEvents = createRouterEvents();
function resolveUrl(url: string | UrlObject): string {
if (typeof url === "string") return url;
let result = url.pathname ?? "/";
if (url.query) {
const params = new URLSearchParams(url.query);
result += `?${params.toString()}`;
}
return result;
}
/**
* Apply locale prefix to a URL for client-side navigation.
* Same logic as Link's applyLocaleToHref but reads from window globals.
*/
export function applyNavigationLocale(url: string, locale?: string): string {
if (!locale || typeof window === "undefined") return url;
const defaultLocale = (window as any).__VINEXT_DEFAULT_LOCALE__;
// Default locale doesn't get a prefix
if (locale === defaultLocale) return url;
// Don't double-prefix
if (url.startsWith(`/${locale}/`) || url === `/${locale}`) return url;
return `/${locale}${url.startsWith("/") ? url : `/${url}`}`;
}
/** Check if a URL is external */
export function isExternalUrl(url: string): boolean {
return url.startsWith("http://") || url.startsWith("https://") || url.startsWith("//");
}
/** Check if a href is only a hash change relative to the current URL */
export function isHashOnlyChange(href: string): boolean {
if (href.startsWith("#")) return true;
if (typeof window === "undefined") return false;
try {
const current = new URL(window.location.href);
const next = new URL(href, window.location.href);
return current.pathname === next.pathname && current.search === next.search && next.hash !== "";
} catch {
return false;
}
}
/** Scroll to hash target element, or top if no hash */
function scrollToHash(hash: string): void {
if (!hash || hash === "#") {
window.scrollTo(0, 0);
return;
}
const el = document.getElementById(hash.slice(1));
if (el) el.scrollIntoView({ behavior: "auto" });
}
/** Save current scroll position into history state for back/forward restoration */
function saveScrollPosition(): void {
const state = window.history.state ?? {};
window.history.replaceState(
{ ...state, __vinext_scrollX: window.scrollX, __vinext_scrollY: window.scrollY },
"",
);
}
/** Restore scroll position from history state */
function restoreScrollPosition(state: unknown): void {
if (state && typeof state === "object" && "__vinext_scrollY" in state) {
const { __vinext_scrollX: x, __vinext_scrollY: y } = state as {
__vinext_scrollX: number;
__vinext_scrollY: number;
};
requestAnimationFrame(() => window.scrollTo(x, y));
}
}
/**
* SSR context - set by the dev server before rendering each page.
*/
interface SSRContext {
pathname: string;
query: Record<string, string | string[]>;
asPath: string;
locale?: string;
locales?: string[];
defaultLocale?: string;
}
// ---------------------------------------------------------------------------
// Server-side SSR state uses a registration pattern so this module can be
// bundled for the browser. The ALS-backed implementation lives in
// router-state.ts (server-only) and registers itself on import.
// ---------------------------------------------------------------------------
let _ssrContext: SSRContext | null = null;
let _getSSRContext = (): SSRContext | null => _ssrContext;
let _setSSRContextImpl = (ctx: SSRContext | null): void => { _ssrContext = ctx; };
/**
* Register ALS-backed state accessors. Called by router-state.ts on import.
* @internal
*/
export function _registerRouterStateAccessors(accessors: {
getSSRContext: () => SSRContext | null;
setSSRContext: (ctx: SSRContext | null) => void;
}): void {
_getSSRContext = accessors.getSSRContext;
_setSSRContextImpl = accessors.setSSRContext;
}
export function setSSRContext(ctx: SSRContext | null): void {
_setSSRContextImpl(ctx);
}
/**
* Extract param names from a Next.js route pattern.
* E.g., "/posts/[id]" → ["id"], "/docs/[...slug]" → ["slug"],
* "/shop/[[...path]]" → ["path"], "/blog/[year]/[month]" → ["year", "month"]
* Also handles internal format: "/posts/:id" → ["id"], "/docs/:slug+" → ["slug"]
*/
function extractRouteParamNames(pattern: string): string[] {
const names: string[] = [];
// Match Next.js bracket format: [id], [...slug], [[...slug]]
const bracketMatches = pattern.matchAll(/\[{1,2}(?:\.\.\.)?([\w-]+)\]{1,2}/g);
for (const m of bracketMatches) {
names.push(m[1]);
}
if (names.length > 0) return names;
// Fallback: match internal :param format
const colonMatches = pattern.matchAll(/:([\w-]+)[+*]?/g);
for (const m of colonMatches) {
names.push(m[1]);
}
return names;
}
function getPathnameAndQuery(): {
pathname: string;
query: Record<string, string>;
asPath: string;
} {
if (typeof window === "undefined") {
const _ssrCtx = _getSSRContext();
if (_ssrCtx) {
const query: Record<string, string> = {};
for (const [key, value] of Object.entries(_ssrCtx.query)) {
query[key] = Array.isArray(value) ? value.join(",") : value;
}
return { pathname: _ssrCtx.pathname, query, asPath: _ssrCtx.asPath };
}
return { pathname: "/", query: {}, asPath: "/" };
}
const pathname = stripBasePath(window.location.pathname);
const query: Record<string, string> = {};
// Include dynamic route params from __NEXT_DATA__ (e.g., { id: "42" } from /posts/[id]).
// Only include keys that are part of the route pattern (not stale query params).
const nextData = (window as any).__NEXT_DATA__;
if (nextData && nextData.query && nextData.page) {
const routeParamNames = extractRouteParamNames(nextData.page);
for (const key of routeParamNames) {
const value = nextData.query[key];
if (typeof value === "string") {
query[key] = value;
} else if (Array.isArray(value)) {
query[key] = value.join(",");
}
}
}
// URL search params always reflect the current URL
const params = new URLSearchParams(window.location.search);
for (const [key, value] of params) {
query[key] = value;
}
const asPath = pathname + window.location.search;
return { pathname, query, asPath };
}
/**
* Perform client-side navigation: fetch the target page's HTML,
* extract __NEXT_DATA__, and re-render the React root.
*/
let _navInProgress = false;
async function navigateClient(url: string): Promise<void> {
if (typeof window === "undefined") return;
const win = window as any;
const root = win.__VINEXT_ROOT__;
if (!root) {
// No React root yet — fall back to hard navigation
window.location.href = url;
return;
}
// Prevent re-entrant navigation (e.g., double popstate events)
if (_navInProgress) return;
_navInProgress = true;
try {
// Fetch the target page's SSR HTML
const res = await fetch(url, { headers: { Accept: "text/html" } });
if (!res.ok) {
window.location.href = url;
return;
}
const html = await res.text();
// Extract __NEXT_DATA__ from the HTML
const match = html.match(/<script>window\.__NEXT_DATA__\s*=\s*(.*?)<\/script>/);
if (!match) {
window.location.href = url;
return;
}
const nextData = JSON.parse(match[1]);
const { pageProps } = nextData.props;
win.__NEXT_DATA__ = nextData;
// Get the page module URL from __NEXT_DATA__.__vinext (preferred),
// or fall back to parsing the hydration script
let pageModuleUrl: string | undefined =
nextData.__vinext?.pageModuleUrl;
if (!pageModuleUrl) {
// Legacy fallback: try to find the module URL in the inline script
const moduleMatch = html.match(/import\("([^"]+)"\);\s*\n\s*const PageComponent/);
const altMatch = html.match(/await import\("([^"]+pages\/[^"]+)"\)/);
pageModuleUrl = moduleMatch?.[1] ?? altMatch?.[1] ?? undefined;
}
if (!pageModuleUrl) {
window.location.href = url;
return;
}
// Validate the module URL before importing — defense-in-depth against
// unexpected __NEXT_DATA__ or malformed HTML responses
if (!isValidModulePath(pageModuleUrl)) {
console.error("[vinext] Blocked import of invalid page module path:", pageModuleUrl);
window.location.href = url;
return;
}
// Dynamically import the new page module
const pageModule = await import(/* @vite-ignore */ pageModuleUrl);
const PageComponent = pageModule.default;
if (!PageComponent) {
window.location.href = url;
return;
}
// Import React for createElement
const React = (await import("react")).default;
// Re-render with the new page, loading _app if needed
let AppComponent = win.__VINEXT_APP__;
const appModuleUrl: string | undefined =
nextData.__vinext?.appModuleUrl;
if (!AppComponent && appModuleUrl) {
if (!isValidModulePath(appModuleUrl)) {
console.error("[vinext] Blocked import of invalid app module path:", appModuleUrl);
} else {
try {
const appModule = await import(/* @vite-ignore */ appModuleUrl);
AppComponent = appModule.default;
win.__VINEXT_APP__ = AppComponent;
} catch {
// _app not available — continue without it
}
}
}
let element;
if (AppComponent) {
element = React.createElement(AppComponent, {
Component: PageComponent,
pageProps,
});
} else {
element = React.createElement(PageComponent, pageProps);
}
root.render(element);
} catch (err) {
console.error("[vinext] Client navigation failed:", err);
routerEvents.emit("routeChangeError", err, url);
window.location.href = url;
} finally {
_navInProgress = false;
}
}
/**
* useRouter hook - Pages Router compatible.
*/
export function useRouter(): NextRouter {
const [{ pathname, query, asPath }, setState] = useState(getPathnameAndQuery);
useEffect(() => {
const onPopState = (e: PopStateEvent) => {
setState(getPathnameAndQuery());
// Re-render with the new page on back/forward navigation
navigateClient(window.location.pathname + window.location.search).then(() => {
restoreScrollPosition(e.state);
});
};
window.addEventListener("popstate", onPopState);
return () => window.removeEventListener("popstate", onPopState);
}, []);
// Listen for custom navigation events from Link component
useEffect(() => {
const onNavigate = ((_e: CustomEvent) => {
setState(getPathnameAndQuery());
}) as EventListener;
window.addEventListener("vinext:navigate", onNavigate);
return () => window.removeEventListener("vinext:navigate", onNavigate);
}, []);
const push = useCallback(
async (url: string | UrlObject, _as?: string, options?: TransitionOptions): Promise<boolean> => {
const resolved = applyNavigationLocale(resolveUrl(url), options?.locale);
// External URLs — delegate to browser
if (isExternalUrl(resolved)) {
window.location.assign(resolved);
return true;
}
// Hash-only change — no page fetch needed
if (isHashOnlyChange(resolved)) {
const hash = resolved.includes("#") ? resolved.slice(resolved.indexOf("#")) : "";
window.history.pushState({}, "", resolved.startsWith("#") ? resolved : withBasePath(resolved));
scrollToHash(hash);
setState(getPathnameAndQuery());
window.dispatchEvent(new CustomEvent("vinext:navigate"));
return true;
}
saveScrollPosition();
const full = withBasePath(resolved);
routerEvents.emit("routeChangeStart", resolved);
window.history.pushState({}, "", full);
if (!options?.shallow) {
await navigateClient(full);
}
setState(getPathnameAndQuery());
routerEvents.emit("routeChangeComplete", resolved);
// Scroll: handle hash target, else scroll to top unless scroll:false
const hash = resolved.includes("#") ? resolved.slice(resolved.indexOf("#")) : "";
if (hash) {
scrollToHash(hash);
} else if (options?.scroll !== false) {
window.scrollTo(0, 0);
}
window.dispatchEvent(new CustomEvent("vinext:navigate"));
return true;
},
[],
);
const replace = useCallback(
async (url: string | UrlObject, _as?: string, options?: TransitionOptions): Promise<boolean> => {
const resolved = applyNavigationLocale(resolveUrl(url), options?.locale);
// External URLs — delegate to browser
if (isExternalUrl(resolved)) {
window.location.replace(resolved);
return true;
}
// Hash-only change — no page fetch needed
if (isHashOnlyChange(resolved)) {
const hash = resolved.includes("#") ? resolved.slice(resolved.indexOf("#")) : "";
window.history.replaceState({}, "", resolved.startsWith("#") ? resolved : withBasePath(resolved));
scrollToHash(hash);
setState(getPathnameAndQuery());
window.dispatchEvent(new CustomEvent("vinext:navigate"));
return true;
}
const full = withBasePath(resolved);
routerEvents.emit("routeChangeStart", resolved);
window.history.replaceState({}, "", full);
if (!options?.shallow) {
await navigateClient(full);
}
setState(getPathnameAndQuery());
routerEvents.emit("routeChangeComplete", resolved);
// Scroll: handle hash target, else scroll to top unless scroll:false
const hash = resolved.includes("#") ? resolved.slice(resolved.indexOf("#")) : "";
if (hash) {
scrollToHash(hash);
} else if (options?.scroll !== false) {
window.scrollTo(0, 0);
}
window.dispatchEvent(new CustomEvent("vinext:navigate"));
return true;
},
[],
);
const back = useCallback(() => {
window.history.back();
}, []);
const reload = useCallback(() => {
window.location.reload();
}, []);
const prefetch = useCallback(async (url: string): Promise<void> => {
// Inject a <link rel="prefetch"> for the target page
if (typeof document !== "undefined") {
const link = document.createElement("link");
link.rel = "prefetch";
link.href = url;
link.as = "document";
document.head.appendChild(link);
}
}, []);
// Get i18n info from SSR context or window
const _ssrState = _getSSRContext();
const locale = typeof window === "undefined"
? _ssrState?.locale
: (window as any).__VINEXT_LOCALE__;
const locales = typeof window === "undefined"
? _ssrState?.locales
: (window as any).__VINEXT_LOCALES__;
const defaultLocale = typeof window === "undefined"
? _ssrState?.defaultLocale
: (window as any).__VINEXT_DEFAULT_LOCALE__;
// route is the route pattern (e.g., "/posts/[id]"), not the actual path
const route = typeof window !== "undefined"
? ((window as any).__NEXT_DATA__?.page ?? pathname)
: pathname;
const router = useMemo(
(): NextRouter => ({
pathname,
route,
query,
asPath,
basePath: __basePath,
locale,
locales,
defaultLocale,
isReady: true,
isPreview: false,
isFallback: typeof window !== "undefined" && (window as any).__NEXT_DATA__?.isFallback === true,
push,
replace,
back,
reload,
prefetch,
beforePopState: (cb: BeforePopStateCallback) => { _beforePopStateCb = cb; },
events: routerEvents,
}),
[pathname, query, asPath, locale, locales, defaultLocale, push, replace, back, reload, prefetch, route],
);
return router;
}
// beforePopState callback: called before handling browser back/forward.
// If it returns false, the navigation is cancelled.
let _beforePopStateCb: BeforePopStateCallback | undefined;
// Module-level popstate listener: handles browser back/forward by re-rendering
// the React root with the page at the new URL. This runs regardless of whether
// any component calls useRouter().
if (typeof window !== "undefined") {
window.addEventListener("popstate", (e: PopStateEvent) => {
const browserUrl = window.location.pathname + window.location.search;
const appUrl = stripBasePath(window.location.pathname) + window.location.search;
// Check beforePopState callback
if (_beforePopStateCb !== undefined) {
const shouldContinue = (_beforePopStateCb as BeforePopStateCallback)({ url: appUrl, as: appUrl, options: { shallow: false } });
if (!shouldContinue) return;
}
routerEvents.emit("routeChangeStart", appUrl);
navigateClient(browserUrl).then(() => {
routerEvents.emit("routeChangeComplete", appUrl);
restoreScrollPosition(e.state);
window.dispatchEvent(new CustomEvent("vinext:navigate"));
});
});
}
// Also export a default Router singleton for `import Router from 'next/router'`
const Router = {
push: async (url: string | UrlObject, _as?: string, options?: TransitionOptions) => {
const resolved = applyNavigationLocale(resolveUrl(url), options?.locale);
// External URLs
if (isExternalUrl(resolved)) {
window.location.assign(resolved);
return true;
}
// Hash-only change
if (isHashOnlyChange(resolved)) {
const hash = resolved.includes("#") ? resolved.slice(resolved.indexOf("#")) : "";
window.history.pushState({}, "", resolved.startsWith("#") ? resolved : withBasePath(resolved));
scrollToHash(hash);
window.dispatchEvent(new CustomEvent("vinext:navigate"));
return true;
}
saveScrollPosition();
const full = withBasePath(resolved);
routerEvents.emit("routeChangeStart", resolved);
window.history.pushState({}, "", full);
if (!options?.shallow) {
await navigateClient(full);
}
routerEvents.emit("routeChangeComplete", resolved);
const hash = resolved.includes("#") ? resolved.slice(resolved.indexOf("#")) : "";
if (hash) {
scrollToHash(hash);
} else if (options?.scroll !== false) {
window.scrollTo(0, 0);
}
window.dispatchEvent(new CustomEvent("vinext:navigate"));
return true;
},
replace: async (url: string | UrlObject, _as?: string, options?: TransitionOptions) => {
const resolved = applyNavigationLocale(resolveUrl(url), options?.locale);
// External URLs
if (isExternalUrl(resolved)) {
window.location.replace(resolved);
return true;
}
// Hash-only change
if (isHashOnlyChange(resolved)) {
const hash = resolved.includes("#") ? resolved.slice(resolved.indexOf("#")) : "";
window.history.replaceState({}, "", resolved.startsWith("#") ? resolved : withBasePath(resolved));
scrollToHash(hash);
window.dispatchEvent(new CustomEvent("vinext:navigate"));
return true;
}
const full = withBasePath(resolved);
routerEvents.emit("routeChangeStart", resolved);
window.history.replaceState({}, "", full);
if (!options?.shallow) {
await navigateClient(full);
}
routerEvents.emit("routeChangeComplete", resolved);
const hash = resolved.includes("#") ? resolved.slice(resolved.indexOf("#")) : "";
if (hash) {
scrollToHash(hash);
} else if (options?.scroll !== false) {
window.scrollTo(0, 0);
}
window.dispatchEvent(new CustomEvent("vinext:navigate"));
return true;
},
back: () => window.history.back(),
reload: () => window.location.reload(),
prefetch: async (url: string) => {
if (typeof document !== "undefined") {
const link = document.createElement("link");
link.rel = "prefetch";
link.href = url;
link.as = "document";
document.head.appendChild(link);
}
},
beforePopState: (cb: BeforePopStateCallback) => {
_beforePopStateCb = cb;
},
events: routerEvents,
};
export default Router;