/// <reference types="node" />
import { PDFOptions, PuppeteerLaunchOptions, Browser } from 'puppeteer';
import { HandlebarsHelpers } from './handlebars-helpers';
export interface GeneratePdfOptions {
    /** Path to the Handlebars template file. */
    templateFilePath: string;
    /** One object per page. Each entry renders the template once; results are concatenated. */
    dataPerPage: Array<object>;
    /** Where to write the PDF. Required unless `useStream` is true. */
    pdfFilePath?: string;
    /** Return a Readable stream of the PDF instead of writing to disk. */
    useStream?: boolean;
    /** Plain object of `{ name: fn }` Handlebars helpers. Preferred over `helpersFilePath`. */
    helpers?: HandlebarsHelpers;
    /**
     * Path to a JSON file of helpers whose values are stringified function bodies.
     * @deprecated Use `helpers` instead — this path runs `new Function` on file contents.
     */
    helpersFilePath?: string;
    /** Puppeteer launch options (only used by the singleton `generatePdf` on first call). */
    puppeteerOptions?: PuppeteerLaunchOptions;
    /** Puppeteer PDF options. Merged on top of A4 / 10mm margin defaults. */
    pdfOptions?: PDFOptions;
}
/**
 * A caller-owned PDF generator. Holds its own Puppeteer Browser instance —
 * isolated from the module singleton used by `generatePdf` / `closeBrowser`.
 *
 * @example
 *   const gen = new PdfGenerator();
 *   try {
 *     await gen.generate({ templateFilePath, dataPerPage, pdfFilePath });
 *   } finally {
 *     await gen.close();
 *   }
 */
export declare class PdfGenerator {
    private browserPromise;
    private readonly launchOptions;
    constructor(launchOptions?: PuppeteerLaunchOptions);
    /** Force the browser to launch now instead of on first `generate()`. */
    warmup(): Promise<Browser>;
    generate(options: GeneratePdfOptions): Promise<string | NodeJS.ReadableStream>;
    close(): Promise<void>;
}
/**
 * Generate a PDF using the shared module-level browser singleton.
 * Call `closeBrowser()` when you're done. For long-running servers or test
 * suites, prefer the `PdfGenerator` class.
 */
export declare const generatePdf: (options: GeneratePdfOptions) => Promise<string | NodeJS.ReadableStream>;