/// <reference types="node" />
import type { Readable } from 'stream';
import type { AvifOptions, JpegOptions, PngOptions, WebpOptions } from 'sharp';
import { ImageFormat } from './ImageFormat';
export declare type Logger = {
    trace: (...data: any[]) => void;
    debug: (...data: any[]) => void;
    info: (...data: any[]) => void;
    warn: (...data: any[]) => void;
    error: (...data: any[]) => void;
};
export declare type CommonConf = {
    assetsBaseUrl: string;
    createFileName?: CreateFileName;
    targetFormats?: (format: ImageFormat) => ImageFormat[];
    fallbackFormat?: (format: ImageFormat) => ImageFormat;
    logger?: Logger;
};
export declare type FetchImage = (src: string) => Readable;
export declare type ServerSideConf = CommonConf & {
    serverSideProcessor: {
        originalDir: string;
        processedDir: string;
        fetch: FetchImage;
        options?: {
            [ImageFormat.JPEG]?: JpegOptions;
            [ImageFormat.PNG]?: PngOptions;
            [ImageFormat.AVIF]?: AvifOptions;
            [ImageFormat.WEBP]?: WebpOptions;
            [ImageFormat.SVG]?: undefined;
            [ImageFormat.GIF]?: undefined;
            [ImageFormat.UNKNOWN]?: undefined;
        };
    };
};
export declare type PictureConf = ServerSideConf | CommonConf;
export declare type ValueReference = {
    filePath: string;
    name?: string;
};
export declare type CreateFileName = (args: {
    src: string;
    format: ImageFormat;
    aspectRatio?: number;
    focalPoint?: [number, number];
    width?: number;
}) => string;
export declare function numberToAspectRatioString(r: number): string;
export declare const defaultCreateFileName: CreateFileName;
export declare function isServersideConf(conf: PictureConf): conf is ServerSideConf;