[mod] client/simple: client plugins (#5406)

* [mod] client/simple: client plugins

Defines a new interface for client side *"plugins"* that coexist with server
side plugin system. Each plugin (e.g., `InfiniteScroll`) extends the base
`ts Plugin`. Client side plugins are independent and lazy‑loaded via `router.ts`
when their `load()` conditions are met. On each navigation request, all
applicable plugins are instanced.

Since these are client side plugins, we can only invoke them once DOM is fully
loaded. E.g. `Calculator` will not render a new `answer` block until fully
loaded and executed.

For some plugins, we might want to handle its availability in `settings.yml`
and toggle in UI, like we do for server side plugins. In that case, we extend
`py Plugin` instancing only the information and then checking client side if
[`settings.plugins`](https://github.com/inetol/searxng/blob/1ad832b1dc33f3f388da361ff2459b05dc86a164/client/simple/src/js/toolkit.ts#L134)
array has the plugin id.

* [mod] client/simple: rebuild static

5 files changed, 0 insertions, 203 deletions

diff --git a/client/simple/src/js/core/index.ts b/client/simple/src/js/core/index.ts
deleted file mode 100644
index 59e64182c..000000000
--- a/client/simple/src/js/core/index.ts
+++ /dev/null
@@ -1,6 +0,0 @@
-// SPDX-License-Identifier: AGPL-3.0-or-later
-
-import "./nojs.ts";
-import "./router.ts";
-import "./toolkit.ts";
-import "./listener.ts";
diff --git a/client/simple/src/js/core/listener.ts b/client/simple/src/js/core/listener.ts
deleted file mode 100644
index b8c0cbfd5..000000000
--- a/client/simple/src/js/core/listener.ts
+++ /dev/null
@@ -1,7 +0,0 @@
-// SPDX-License-Identifier: AGPL-3.0-or-later
-
-import { listen } from "./toolkit.ts";
-
-listen("click", ".close", function (this: HTMLElement) {
-  (this.parentNode as HTMLElement)?.classList.add("invisible");
-});
diff --git a/client/simple/src/js/core/nojs.ts b/client/simple/src/js/core/nojs.ts
deleted file mode 100644
index 65c62dd90..000000000
--- a/client/simple/src/js/core/nojs.ts
+++ /dev/null
@@ -1,8 +0,0 @@
-// SPDX-License-Identifier: AGPL-3.0-or-later
-
-import { ready } from "./toolkit.ts";
-
-ready(() => {
-  document.documentElement.classList.remove("no-js");
-  document.documentElement.classList.add("js");
-});
diff --git a/client/simple/src/js/core/router.ts b/client/simple/src/js/core/router.ts
deleted file mode 100644
index bea838713..000000000
--- a/client/simple/src/js/core/router.ts
+++ /dev/null
@@ -1,40 +0,0 @@
-// SPDX-License-Identifier: AGPL-3.0-or-later
-
-import { Endpoints, endpoint, ready, settings } from "./toolkit.ts";
-
-ready(
-  () => {
-    void import("../main/keyboard.ts");
-    void import("../main/search.ts");
-
-    if (settings.autocomplete) {
-      void import("../main/autocomplete.ts");
-    }
-  },
-  { on: [endpoint === Endpoints.index] }
-);
-
-ready(
-  () => {
-    void import("../main/keyboard.ts");
-    void import("../main/mapresult.ts");
-    void import("../main/results.ts");
-    void import("../main/search.ts");
-
-    if (settings.infinite_scroll) {
-      void import("../main/infinite_scroll.ts");
-    }
-
-    if (settings.autocomplete) {
-      void import("../main/autocomplete.ts");
-    }
-  },
-  { on: [endpoint === Endpoints.results] }
-);
-
-ready(
-  () => {
-    void import("../main/preferences.ts");
-  },
-  { on: [endpoint === Endpoints.preferences] }
-);
diff --git a/client/simple/src/js/core/toolkit.ts b/client/simple/src/js/core/toolkit.ts
deleted file mode 100644
index d80167aa5..000000000
--- a/client/simple/src/js/core/toolkit.ts
+++ /dev/null
@@ -1,142 +0,0 @@
-// SPDX-License-Identifier: AGPL-3.0-or-later
-
-import type { KeyBindingLayout } from "../main/keyboard.ts";
-
-// synced with searx/webapp.py get_client_settings
-type Settings = {
-  advanced_search?: boolean;
-  autocomplete?: string;
-  autocomplete_min?: number;
-  doi_resolver?: string;
-  favicon_resolver?: string;
-  hotkeys?: KeyBindingLayout;
-  infinite_scroll?: boolean;
-  method?: "GET" | "POST";
-  query_in_title?: boolean;
-  results_on_new_tab?: boolean;
-  safesearch?: 0 | 1 | 2;
-  search_on_category_select?: boolean;
-  theme?: string;
-  theme_static_path?: string;
-  translations?: Record<string, string>;
-  url_formatting?: "pretty" | "full" | "host";
-};
-
-type HTTPOptions = {
-  body?: BodyInit;
-  timeout?: number;
-};
-
-type ReadyOptions = {
-  // all values must be truthy for the callback to be executed
-  on?: (boolean | undefined)[];
-};
-
-type AssertElement = (element?: HTMLElement | null) => asserts element is HTMLElement;
-
-export type EndpointsKeys = keyof typeof Endpoints;
-
-export const Endpoints = {
-  index: "index",
-  results: "results",
-  preferences: "preferences",
-  unknown: "unknown"
-} as const;
-
-export const mutable = {
-  closeDetail: undefined as (() => void) | undefined,
-  scrollPageToSelected: undefined as (() => void) | undefined,
-  selectImage: undefined as ((resultElement: HTMLElement) => void) | undefined,
-  selectNext: undefined as ((openDetailView?: boolean) => void) | undefined,
-  selectPrevious: undefined as ((openDetailView?: boolean) => void) | undefined
-};
-
-const getEndpoint = (): EndpointsKeys => {
-  const metaEndpoint = document.querySelector('meta[name="endpoint"]')?.getAttribute("content");
-
-  if (metaEndpoint && metaEndpoint in Endpoints) {
-    return metaEndpoint as EndpointsKeys;
-  }
-
-  return Endpoints.unknown;
-};
-
-const getSettings = (): Settings => {
-  const settings = document.querySelector("script[client_settings]")?.getAttribute("client_settings");
-  if (!settings) return {};
-
-  try {
-    return JSON.parse(atob(settings));
-  } catch (error) {
-    console.error("Failed to load client_settings:", error);
-    return {};
-  }
-};
-
-export const assertElement: AssertElement = (element?: HTMLElement | null): asserts element is HTMLElement => {
-  if (!element) {
-    throw new Error("Bad assertion: DOM element not found");
-  }
-};
-
-export const http = async (method: string, url: string | URL, options?: HTTPOptions): Promise<Response> => {
-  const controller = new AbortController();
-  const timeoutId = setTimeout(() => controller.abort(), options?.timeout ?? 30_000);
-
-  const res = await fetch(url, {
-    body: options?.body,
-    method: method,
-    signal: controller.signal
-  }).finally(() => clearTimeout(timeoutId));
-  if (!res.ok) {
-    throw new Error(res.statusText);
-  }
-
-  return res;
-};
-
-export const listen = <K extends keyof DocumentEventMap, E extends HTMLElement>(
-  type: string | K,
-  target: string | Document | E,
-  listener: (this: E, event: DocumentEventMap[K]) => void | Promise<void>,
-  options?: AddEventListenerOptions
-): void => {
-  if (typeof target !== "string") {
-    target.addEventListener(type, listener as EventListener, options);
-    return;
-  }
-
-  document.addEventListener(
-    type,
-    (event: Event) => {
-      for (const node of event.composedPath()) {
-        if (node instanceof HTMLElement && node.matches(target)) {
-          try {
-            listener.call(node as E, event as DocumentEventMap[K]);
-          } catch (error) {
-            console.error(error);
-          }
-          break;
-        }
-      }
-    },
-    options
-  );
-};
-
-export const ready = (callback: () => void, options?: ReadyOptions): void => {
-  for (const condition of options?.on ?? []) {
-    if (!condition) {
-      return;
-    }
-  }
-
-  if (document.readyState !== "loading") {
-    callback();
-  } else {
-    listen("DOMContentLoaded", document, callback, { once: true });
-  }
-};
-
-export const endpoint: EndpointsKeys = getEndpoint();
-export const settings: Settings = getSettings();