/**
 * pendingFn 回调函数接收的参数
 */
type PendingFnParams = {
    /** 解析后的 scope key */
    scope: string;
    /** 获取当前等待中的 caller 数量（实时值） */
    getPendingCount: () => number;
};

declare class MountRemoteError extends Error {
    readonly prev?: unknown | undefined;
    constructor(message: string, prev?: unknown | undefined);
}
type MountRemoteResult<Result extends Record<string, unknown> = Record<string, unknown>> = {
    type: string;
    scope: string;
} & Result;
/**
 * Handler 上下文，继承 PendingFnParams
 */
type MountHandlerContext<Options extends Record<string, unknown> = Record<string, unknown>> = PendingFnParams & {
    type: string;
} & Options;
/**
 * DOM 类型 handler 的通用选项
 */
type MountDomOptions = {
    url: string;
    attrs?: Record<string, string>;
    onLoad?: (el: HTMLElement, res: MountRemoteResult<MountDomResult>) => void | Promise<void>;
    onError?: (err: unknown, ctx: MountHandlerContext<MountDomOptions>, opts: MountDomOptions) => void;
};
/**
 * DOM handler 的扩展返回字段（不含 MountRemoteResult 的基础字段）
 */
type MountDomResult = MountDomOptions & {
    id: string;
    el: HTMLElement;
};
/**
 * 类型安全的 handler 函数
 */
type MountHandlerFn<Options extends Record<string, unknown> = Record<string, unknown>, Result extends Record<string, unknown> = Record<string, unknown>> = (ctx: MountHandlerContext<Options>, opts: Options) => Promise<MountRemoteResult<Result>> | MountRemoteResult<Result>;
/**
 * Handler 类型映射表
 *
 * 通过 interface 声明合并扩展：
 * ```ts
 * declare module '@zenstone/ts-utils/remote' {
 *   interface MountHandlerMap {
 *     wasm: MountHandlerFn<{ url: string; importObject?: WebAssembly.Imports }>;
 *   }
 * }
 * ```
 */
interface MountHandlerMap {
    js: MountHandlerFn<MountDomOptions, MountDomResult>;
    css: MountHandlerFn<MountDomOptions, MountDomResult>;
    mjs: MountHandlerFn<MountDomOptions, MountDomResult>;
}
/**
 * 注册挂载类型处理器
 *
 * @param type 资源类型标识
 * @param handler 处理函数
 *
 * @example
 * ```ts
 * registerMountHandler('wasm', async (ctx, opts) => {
 *   const response = await fetch(opts.url);
 *   const module = await WebAssembly.instantiateStreaming(response, opts.importObject);
 *   return { type: ctx.type, scope: ctx.scope, url: opts.url, module };
 * });
 * ```
 */
declare const registerMountHandler: <K extends keyof MountHandlerMap>(type: K, handler: MountHandlerMap[K]) => void;
/**
 * 创建基于 DOM 元素的挂载处理器
 *
 * 适用于通过 script/link 等标签加载的资源。自动处理：
 * - `getElementById` 短路检查
 * - 创建元素并设置属性
 * - 设置 id（使用 scope）
 * - 监听 load/error 事件
 * - 挂载到 document.head
 *
 * @param tagName 标签名
 * @param setup 元素初始化函数
 *
 * @example
 * ```ts
 * registerMountHandler('img', createDomHandler('img', (el, ctx) => {
 *   el.setAttribute('src', ctx.url);
 * }));
 * ```
 */
declare const createDomHandler: (tagName: string, setup: (el: HTMLElement, ctx: MountHandlerContext<MountDomOptions>) => void) => MountHandlerFn<MountDomOptions, MountDomResult>;
/**
 * 挂载远程资源
 *
 * 基于 scope 做 inflight 去重：并发调用同 scope 只执行一次，结果共享。
 * Options 类型由 `type` 字段决定，通过 {@link MountHandlerMap} 接口扩展。
 *
 * 内置支持 `js`、`mjs`、`css` 三种类型，其他类型需通过
 * {@link registerMountHandler} 注册处理器。
 *
 * @param scope 去重标识，同时用作 DOM 元素 id（对于 DOM handler）
 * @param options 挂载选项，类型由 `type` 决定
 *
 * @example
 * ```ts
 * await mountRemote('jquery', {
 *   type: 'js',
 *   url: 'https://cdn.example.com/jquery.min.js',
 * });
 * ```
 *
 * @example 并发去重
 * ```ts
 * await Promise.all([
 *   mountRemote('lib', { type: 'js', url }),
 *   mountRemote('lib', { type: 'js', url }),
 * ]);
 * // 只加载一次
 * ```
 */
declare function mountRemote<K extends keyof MountHandlerMap>(scope: string, options: {
    type: K;
} & Parameters<MountHandlerMap[K]>[1]): Promise<MountRemoteResult>;
/**
 * 基于 id 移除已挂载的远程资源
 *
 * @param id 元素 ID
 * @param onRemove 移除后回调
 */
declare const unmountDomRemote: (id: string, onRemove?: () => void) => void;

export { MountRemoteError, createDomHandler, mountRemote, registerMountHandler, unmountDomRemote };
export type { MountDomOptions, MountDomResult, MountHandlerContext, MountHandlerFn, MountHandlerMap, MountRemoteResult };